Neuropsychological Outcomes After Insular Tumor Resection: Focus on Neurologically Intact Patients Following Transsylvian–Transinsular Resection in the Dominant Hemisphere

Neuropsychological Outcomes After Insular Tumor Resection: Focus on Neurologically Intact Patients Following Transsylvian–Transinsular Resection in the Dominant Hemisphere | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Neuropsychological Outcomes After Insular Tumor Resection: Focus on Neurologically Intact Patients Following Transsylvian–Transinsular Resection in the Dominant Hemisphere Jakhongirmirzo Yoldoshev, Uygun Altibayev, Gayrat Kariev, Alvaro Campero This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9006163/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Gliomas of the dominant insular lobe represent functionally critical tumors in which overt neurological deficits may be absent despite involvement of language-related and associative networks. In such cases, standard neurological examination does not always adequately reflect the status of higher cognitive functions, underscoring the importance of neuropsychological assessment for a comprehensive evaluation of functional outcomes following surgical treatment. Objective To evaluate neuropsychological outcomes in patients with gliomas of the dominant insular lobe, with particular emphasis on a functional analysis of the subgroup undergoing resection via the transsylvian–transinsular approach, aiming to identify subclinical cognitive alterations in the absence of clinically significant neurological deficits. Materials and Methods A prospective, single-center observational cohort study was conducted between January 2023 and December 2025. Thirty-one patients aged 18–52 years were included. Hemispheric dominance was determined clinically based on handedness. All tumors were classified as gliomas according to the WHO classification (LGG/HGG). In 12 patients, the tumor was located in the left insular lobe; among them, 8 patients underwent resection via the transsylvian–transinsular approach, which was applied in individuals with a clinically preserved preoperative neurological status allowing standardized neuropsychological assessment. The extent of resection comprised subtotal resection (STR) in 9 patients and gross total resection (GTR) in 3 patients. Neuropsychological evaluation was performed in all patients during the preoperative and postoperative periods; in patients with transient motor aphasia, testing was conducted after regression of the speech deficit. One illustrative clinical case is presented using intraoperative images. Results In the early postoperative period, transient neurological disturbances were observed in three patients with dominant insular tumors who underwent resection via the transsylvian–transinsular approach: motor deficits in two patients and motor aphasia in one patient. No new permanent neurological deficits were identified compared with the preoperative status, and all transient deficits completely resolved during follow-up. Neuropsychological assessment revealed cognitive alterations in a subset of patients both in the early postoperative period and during subsequent follow-up, including patients with clinically preserved or recovered neurological status. The profile and severity of neuropsychological impairments varied across patients and time points, as detailed in the corresponding tables. Conclusion Within the framework of this prospective study, it was demonstrated that a clinically preserved neurological status after surgical treatment of dominant insular gliomas does not necessarily reflect the integrity of higher cognitive functions. Despite the absence of permanent motor or language deficits, neuropsychological assessment identified cognitive alterations in a subset of patients, including those with an otherwise neurologically intact clinical presentation. In this context, neuropsychological testing proved to be more sensitive than standard neurological examination in detecting subclinical cognitive impairments following tumor resection via the transsylvian–transinsular approach. Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 INTRODUCTION Insular gliomas are among the most challenging tumors to treat surgically due to their deep-seated location, close anatomical relationships with cortical and subcortical functional networks, and marked variability of the vascular architecture [ 1 – 3 , 7 , 21 ]. The insula constitutes a key component of the limbic and paralimbic systems and plays an essential role in the regulation of language, executive, affective, and integrative cognitive functions [ 1 , 2 , 10 , 11 , 15 , 17 ]. Historically, the high rate of postoperative complications led to a cautious attitude toward aggressive surgical management of tumors in this region, particularly when located in the dominant hemisphere [ 18 , 20 , 21 , 38 , 39 ]. Advances in microsurgical techniques, improved understanding of the topographic and microanatomy of the insular region, and the introduction of functionally oriented surgical concepts have substantially changed the management of insular gliomas [ 2 , 3 , 10 , 16 , 22 , 23 ]. Contemporary clinical series demonstrate that, with careful patient selection and appropriate choice of surgical approach, a meaningful extent of resection can be achieved with an acceptable rate of neurological morbidity [ 9 , 14 , 25 , 28 , 33 , 38 ]. In this context, the transsylvian–transinsular approach is regarded as an anatomically sound corridor to insular tumors, allowing minimization of cortical injury while providing direct visualization of vascular and subcortical structures [ 4 , 21 , 29 , 30 , 33 , 34 , 48 ]. Despite their location within the dominant hemisphere, insular gliomas frequently present without clinically evident neurological deficits [ 10 , 13 , 16 ]. This phenomenon has been attributed both to the slow-growing nature of these tumors, enabling functional reorganization, and to the distributed organization of language and cognitive networks [ 10 – 12 , 16 ]. As a result, standard neurological examination may fail to detect functional impairment even when eloquent structures are involved, thereby limiting its sensitivity for assessing functional outcomes after surgical treatment [ 9 , 24 , 37 ]. In recent years, increasing attention has been directed toward neuropsychological methods as more sensitive tools for the evaluation of higher cortical functions [ 11 , 13 , 37 , 45 , 46 ]. Neuropsychological testing allows the detection of subclinical cognitive impairments that are not identified during routine neurological examination but may significantly affect daily functioning and quality of life [ 37 , 44 ]. Nevertheless, data on neuropsychological outcomes following resection of dominant insular gliomas remain limited, as most published studies primarily focus on gross neurological complications, extent of resection, and oncological outcomes [ 9 , 14 , 24 , 33 , 52 ]. Transient postoperative disturbances, including motor and language deficits, warrant particular attention, as their underlying pathophysiological mechanisms remain incompletely understood [ 9 , 24 , 41 , 42 ]. In addition to direct cortical or subcortical injury, increasing emphasis has been placed on venous factors, especially in the perisylvian region, where even minor disturbances of venous drainage may result in reversible functional deficits [ 3 , 26 , 35 , 40 ]. Analysis of such clinical scenarios requires integration of intraoperative findings, neuroimaging data, and functional outcomes. In light of these considerations, a comprehensive approach to the evaluation of functional outcomes after surgical treatment of dominant insular gliomas appears warranted, incorporating not only standard neurological examination but also systematic neuropsychological assessment [ 11 , 16 , 37 , 49 , 51 ]. The present study aims to analyze neuropsychological outcomes in patients with dominant insular gliomas following surgical treatment, with an in-depth functional analysis of the subgroup undergoing resection via the transsylvian–transinsular approach and a particular focus on identifying subclinical cognitive impairments in the absence of clinically significant neurological deficits. MATERIALS AND METHODS Study Design and Ethical Considerations A prospective observational cohort study was conducted at a single specialized neurosurgical center—the Republican Specialized Scientific and Practical Medical Center of Neurosurgery (Tashkent, Uzbekistan). The study protocol was approved by the local institutional ethics committee and was conducted in accordance with the ethical principles of the Declaration of Helsinki (2013 revision). Written informed consent for surgical treatment and the use of clinical data for research purposes was obtained from all patients prior to inclusion in the study. Patient Characteristics Between January 2023 and December 2025, a total of 31 patients with insular gliomas who underwent surgical treatment were prospectively evaluated. In 12 patients, the tumor was located in the dominant insular lobe. Among them, 8 patients underwent tumor resection using the transsylvian–transinsular approach, and this subgroup constituted the primary study cohort (table. 1). Patients with a clinically preserved preoperative neurological status were included, allowing standardized neuropsychological assessment. Patients with significant preoperative neurological deficits that could compromise the reliability of cognitive evaluation were excluded from the neuropsychological outcome analysis. Table 1 Clinical, Demographic, and Surgical Characteristics of Patients with Insular Tumors According to Hemispheric Dominance. N o n - D o m i n a n t № Side KPS Score Education level Location Approach STR/GT WHO Grade 1 Rt 100 1 Medial extension T-T STR II 2 Rt 90 2 Medial extension T-T STR II 3 Rt 90 2 Pure insular T-T STR II 4 Rt 100 2 Pure insular T-T STR II 5 Rt 100 2 Pure insular T-T GT II 6 Rt 90 3 Lateral extension T-T STR III 7 Rt 90 2 Pure insular T-T STR II 8 Rt 100 2 Medial extension T-T STR II 9 Rt 100 1 Pure insular T-T STR II 10 Rt 100 2 Lateral extension T-F GT II 11 Rt 100 3 Lateral extension T-F GT II 12 Rt 100 2 Lateral extension T-F GT II 13 Rt 90 2 Lateral extension T-F STR III 14 Rt 100 1 Lateral extension T-F GT III 15 Rt 100 1 Lateral extension T-T STR II 16 Rt 100 2 Lateral extension T-T STR II 17 Rt 80 2 Lateral extension T-T GT II 18 Rt 90 1 Multiregional Combined STR III 19 Rt 90 2 Multiregional Combined STR III D o m i n a n t 20 Lt 100 1 Pure insular T-T STR II 21 Lt 100 2 Pure insular T-T GT II 22 Lt 100 1 Medial extension T-T STR II 23 Lt 90 2 Medial extension T-T STR III 24 Lt 100 2 Pure insular T-T GT II 25 Lt 100 1 Pure insular T-T STR II 26 Lt 100 3 Medial extension T-T STR II 27 Lt 100 2 Pure insular T-T STR II 28 Lt 90 3 Lateral extension TO + AS STR II 29 Lt 100 2 Lateral extension TO + AS STR II 30 Lt 100 1 Lateral extension TO + AS GT II 31 Lt 100 2 Lateral extension TO + AS STR III Determination of the Dominant Hemisphere The dominant hemisphere was determined clinically based on handedness, in accordance with widely accepted clinical practice. Only patients with clearly identifiable hemispheric dominance were included in the analysis, allowing reliable interpretation of functional and neuropsychological outcomes. Preoperative Neuroimaging All patients underwent a standardized preoperative neuroimaging protocol, including contrast-enhanced brain MRI (T1-weighted images), T2- and FLAIR-weighted sequences, diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), and MR angiography using a 3D time-of-flight (3D-TOF) technique. The acquired imaging data were used for anatomical tumor assessment, surgical approach planning, and evaluation of the relationships between the lesion and adjacent vascular and subcortical structures. Surgical Technique Surgical procedures were performed using two anesthetic protocols depending on the selected surgical strategy. Resections carried out via the transsylvian–transinsular approach were performed under general anesthesia, whereas patients operated on under awake conditions underwent an awake craniotomy protocol with intraoperative language mapping. Among the 12 patients with dominant insular gliomas, tumor resection was performed via the transsylvian–transinsular approach in 8 patients and using awake craniotomy in 4 patients. For the transsylvian–transinsular approach, microsurgical dissection of the Sylvian fissure was performed without cortical incision. Depending on tumor location and individual vascular anatomy, two dissection trajectories were employed: a medial-to-lateral approach in 5 patients and a lateral-to-medial approach in 3 patients. In patients with tumors located in the non-dominant hemisphere, the choice of surgical approach was determined by tumor location, extent, and relationships with cortical and subcortical structures. According to anatomical characteristics, the following approaches were used: transsylvian–transinsular (n = 9), transfrontal (n = 5), transtemporal (n = 3), and combined approaches (n = 2). All procedures in this group were performed under general anesthesia in accordance with the principles of functionally oriented microsurgery. In all procedures performed via the transsylvian–transinsular approach, intraoperative neurophysiological monitoring with motor evoked potential (MEP) recording was utilized to assess the functional integrity of subcortical motor pathways. Neuronavigation was not employed; instead, individualized preoperative three-dimensional planning based on neuroimaging data was used to define optimal surgical corridors and to evaluate the relationships between the tumor and adjacent vascular and subcortical structures. Assessment of the Extent of Resection The extent of tumor resection was assessed based on early postoperative contrast-enhanced MRI performed on the second postoperative day. Gross total resection (GTR) was defined as the absence of residual tumor on postoperative neuroimaging, whereas subtotal resection (STR) was recorded when residual tumor tissue was present. Within the subgroup of patients with dominant insular gliomas, subtotal resection was achieved in 9 patients, including 6 cases treated via the transsylvian–transinsular approach, while gross total resection was achieved in 3 patients, 2 of whom underwent surgery using the transsylvian–transinsular approach. Postoperative Neuroimaging All patients underwent non-contrast computed tomography of the brain within the first postoperative day to exclude hemorrhagic complications. Follow-up contrast-enhanced MRI was performed on the second postoperative day to assess the extent of resection and to identify ischemic or structural changes. Neurological Assessment Neurological status was assessed preoperatively, in the early postoperative period, and during follow-up. New neurological deficits were defined as impairments not present in the preoperative period. Transient and permanent neurological deficits were analyzed separately. Neuropsychological Assessment Neuropsychological assessment was performed in all patients during the preoperative and postoperative periods using standardized and validated test batteries aimed at evaluating language functions, executive functions, attention, and memory, in accordance with international recommendations. Assessment of language functions included naming and verbal productivity tasks, such as the Boston Naming Test and tests of phonemic and semantic verbal fluency. Executive functions and attention were evaluated using the Trail Making Test (parts A and B) and tasks assessing cognitive control, whereas memory was examined using the Digit Span (forward and backward) and verbal memory tests. Neuropsychological testing was conducted at standardized follow-up time points; in patients with transient speech disturbances, repeat assessment was performed after clinical resolution of aphasia. Postoperative testing was carried out under conditions of stable clinical status. In a patient with transient motor aphasia, neuropsychological assessment was performed only after complete resolution of the speech deficit. In patients with a history of epileptic seizures, testing was conducted during the interictal period; assessment was postponed in the presence of recent seizures or postictal symptoms. Statistical Analysis Given the exploratory nature of the study, the limited sample size, and the primarily descriptive focus of the analysis, statistical data processing was predominantly descriptive. Quantitative variables are presented as means or medians with corresponding ranges, whereas qualitative data are reported as absolute values and percentages. Formal statistical comparisons and hypothesis testing were not performed, as the aim of the study was to identify general trends and patterns of functional changes rather than to establish causal relationships. RESULTS Overall cohort characteristics In the studied prospective series of 31 patients, the tumor was localized in the dominant insular lobe in 12 patients. Within this subgroup, surgical intervention was performed using a transsylvian–transinsular approach in 8 patients; these patients were included in the analysis of neuropsychological outcomes. Preoperatively, the neurological status of all patients in this subgroup was assessed as clinically intact. In the early postoperative period, motor deficits were observed in two patients, and one patient developed transient motor aphasia. In all cases, these neurological disturbances were temporary and fully resolved during subsequent follow-up. Compared with the preoperative condition, no new permanent neurological deficits were identified. Illustrative clinical case As an illustrative clinical case, we present a patient with a tumor of the left (dominant) insular region, selected based on a combination of anatomical and clinico-radiological characteristics as well as specific features of the intraoperative course. The tumor demonstrated predominantly medial growth from the insular lobe with close proximity to subcortical structures, which determined the high functional relevance of the surgical intervention. The patient was followed dynamically for two years; according to MRI performed 2 years and 4 months prior to surgery, a slowly progressive tumor lesion was identified, without a pronounced mass effect and in the absence of a clinically significant neurological deficit (fig. 1). This case was also selected because of an intraoperative technical particularity—injury to a small cortical vein during dissection of the Sylvian fissure. In the remaining cases of the studied series, no intraoperative technical complications were observed. The presented case illustrates the potential challenges of microsurgical dissection in the perisylvian region and emphasizes the importance of detailed analysis of venous anatomy when performing a transsylvian–transinsular approach Preoperative contrast-enhanced magnetic resonance imaging revealed a tumor of the insular region with predominantly medial extension, spreading toward the subcortical structures without clear evidence of their gross infiltration. The lesion was characterized by a heterogeneous structure and well-visualized margins on T2- and FLAIR-weighted sequences, while no marked mass effect or compression of the surrounding anatomical structures was observed. The relationships between the tumor and the adjacent subcortical white matter tracts and vascular structures were considered close, which was of critical importance for planning the surgical approach (fig. 2). According to 3D time-of-flight (3D-TOF) MR angiography, the major intracranial arterial structures were clearly visualized, without evidence of compression, stenosis, or tumor invasion, indicating preservation of the primary arterial blood supply within the affected region. Diffusion tensor imaging (DTI) demonstrated displacement of the adjacent white matter tracts as a result of the tumor-related mass effect, while their structural integrity was preserved, with no signs of tract disruption or marked fiber destruction. These findings were of key importance for the selection of the surgical strategy and for planning a safe transsylvian–transinsular approach (fig. 3). Intraoperative findings Tumor resection was performed via a transsylvian–transinsular approach. Microsurgical dissection of the Sylvian fissure enabled the creation of a direct corridor to the lesion without the need for a cortical incision. During surgery, injury to a small cortical vein in the perisylvian region was noted (fig. 4). No arterial injuries were recorded. The tumor was removed within the preplanned extent while preserving the subcortical structures. Intraoperative neurophysiological monitoring with motor evoked potentials was employed during the resection phase, including subcortical stimulation. As functionally eloquent white matter pathways were approached, responses to subcortical stimulation were elicited, indicating close proximity of the motor tracts and serving as the basis for terminating further resection in that direction. Consequently, the extent of resection was limited by functional boundaries, allowing achievement of the planned resection volume without injury to the subcortical white matter tracts (subcortical stimulation threshold ≤ 3–5 mA; preservation of motor evoked potentials without significant amplitude or latency changes). Postoperative imaging results Postoperative computed tomography performed within the first 24 hours after surgery revealed no evidence of intracranial hemorrhage or significant cerebral edema (fig. 5). Contrast-enhanced magnetic resonance imaging of the brain performed on the second postoperative day confirmed the achieved extent of resection, with no evidence of residual tumor tissue within the resection area. Additionally, no signs of ischemic changes, hemorrhagic complications, or pathological contrast enhancement were identified in the adjacent cortical or subcortical structures, indicating preservation of regional blood supply and functionally eloquent anatomical structures (fig. 6). Neurological and neuropsychological outcomes In the early postoperative period, two patients developed moderate motor deficits (up to 3 points on the MRC scale), which completely resolved within two weeks, whereas one patient developed transient motor aphasia without an associated motor deficit, with full recovery of speech function within five days of follow-up (table. 2). Table. 2. Neurological outcomes after surgical treatment of insular gliomas according to hemispheric dominance and type of surgical approach. Outcome Hemisphere Surgical approach Pre-op Post-op day 3 Post-op day 7 Week 4 Month 3 Year 1 Motor deficit Dominant Transsylvian transinsular (n=8) 0 2 (25%) 1 (12.5%) 1 (12.5%) 0 0 Awake surgery (n=4) 1 (25%) 2 (50%) 2 (50%) 1 (25%) 0 0 Non-dominant Transsylvian–transinsular (n=9) 2 (22.2%) 2 (22.2%) 2 (22.2%) 1 (11.1%) 1 (11.1%) 0 Transfrontal (n=5) 0 0 0 0 0 0 Transtemporal (n=3) 1 (33.3%) 1 (33.3%) 1 (33.3%) 0 0 0 Combined approach (n=2) 1 (50%) 1 (50%) 1 (50%) 1 (50%) 1 (50%) 1 (50%) Language deficit Dominant Transsylvian–transinsular (n=8) 0 (%) 1 (12.5%) 0 0 0 0 Awake Surgery (n=4) 0 1 (25%) 0 0 0 0 Neuropsychological assessment performed after resolution of aphasia revealed subclinical cognitive changes that were not accompanied by clinically significant neurological deficits. The profile of the identified neuropsychological impairments did not fully correlate with the findings of standard neurological examination. Preoperatively, seizure disorder was present in a subset of patients in both hemispheres. Following surgical treatment, a progressive reduction in seizure frequency was observed over the course of follow-up, with the most pronounced improvement at 3 months and 1 year after the intervention (table. 3). Table 3. Seizure outcomes before and after surgical treatment of insular gliomas according to hemisphere and surgical approach. Hemisphere Surgical approach Pre-op Post-op day 3 Post-op day 7 Week 4 Month 3 Year 1 Dominant hemisphere Transsylvian–transinsular (n = 8) 6 (75%) 3 (37.5%) 2 (25%) 2 (25%) 1 (12.5%) 1 (12.5%) Awake surgery (n = 4) 3 (75%) 2 (50%) 1 (25%) 1 (25%) 1 (25%) 0 (0%) Non-dominant hemisphere Transsylvian–transinsular (n = 9) 5 (55.6%) 3 (33.3%) 2 (22.2%) 2 (22.2%) 1 (11.1%) 1 (11.1%) Transfrontal (n = 5) 2 (40%) 1 (20%) 1 (20%) 0 (0%) 0 (0%) 0 (0%) Transtemporal (n = 3) 2 (66.7%) 1 (33.3%) 1 (33.3%) 1 (33.3%) 1 (33.3%) 0 (0%) Combined approach (n = 2) 2 (100%) 2 (100%) 2 (100%) 2 (100%) 1 (50%) 1 (50%) At 3 months after surgery, favorable seizure control (Engel class I) was achieved in the majority of patients, regardless of the affected hemisphere and the surgical approach used, with further improvement or stabilization of outcomes by 1 year of follow-up (table. 4). Table 4. Seizure control according to the Engel classification in the long-term period after resection of insular gliomas. Hemisphere Surgical approach Month 3 Year 1 Dominant Transsylvian–transinsular (n = 8) 7 (87.5%) 7 (87.5%) Dominant Awake surgery (n = 4) 3 (75%) 4 (100%) Non-dominant Transsylvian–transinsular (n = 9) 8 (88.9%) 8 (88.9%) Non-dominant Other approaches (n = 10) 7 (70%) 8 (80%) In patients with gliomas of the dominant insular lobe, neuropsychological impairments were already present in the preoperative period and demonstrated worsening in the early postoperative phase. Language, executive, and mnemonic functions were most frequently affected, with the greatest severity of deficits observed on postoperative day 7. Subsequently, a trend toward partial regression of cognitive disturbances was noted; however, in a substantial proportion of patients, impairment in at least one cognitive domain persisted even at 1 year of follow-up, despite the absence of clinically significant neurological deficits (table. 5). Table 5. Dynamics of neuropsychological impairments across cognitive domains in patients with gliomas of the dominant insular lobe. Cognitive domain Surgical approach Pre-op Post-op day 7 Week 4 Month 3 Year 1 Language Transsylvian–transinsular (n=8) 1 (12.5%) 4 (50%) 3 (37.5%) 2 (25%) 1 (12.5%) Awake surgery (n=4) 1 (25%) 3 (75%) 2 (50%) 1 (25%) 1 (25%) Memory Transsylvian–transinsular (n=8) 2 (25%) 5 (62.5%) 4 (50%) 3 (37.5%) 2 (25%) Awake surgery (n=4) 1 (25%) 2 (50%) 2 (50%) 1 (25%) 1 (25%) Attention / Executive Transsylvian–transinsular (n=8) 2 (25%) 6 (75%) 5 (62.5%) 4 (50%) 3 (37.5%) Awake surgery (n=4) 1 (25%) 3 (75%) 2 (50%) 2 (50%) 1 (25%) Visuospatial / Praxis Transsylvian–transinsular (n=8) 1 (12.5%) 3 (37.5%) 2 (25%) 1 (12.5%) 1 (12.5%) Awake surgery (n=4) 0 (0%) 1 (25%) 1 (25%) 0 (0%) 0 (0%) ≥1 cognitive domain impaired Transsylvian–transinsular (n=8) 3 (37.5%) 7 (87.5%) 6 (75%) 5 (62.5%) 4 (50%) Awake surgery (n=4) 2 (50%) 4 (100%) 3 (75%) 2 (50%) 2 (50%) In patients with gliomas of the nondominant insular lobe, neuropsychological impairments were identified predominantly in the domains of memory, attention, and executive functions, with an increase in their frequency in the early postoperative period. The most pronounced and persistent cognitive changes were observed in patients operated on using transtemporal and combined approaches. Subsequently, partial regression of these impairments was noted; however, in a subset of patients, involvement of at least one cognitive domain persisted even at 1 year of follow-up, underscoring the functional significance of the nondominant insular region (table. 6). Table 6. Neuropsychological impairments across cognitive domains in patients with gliomas of the nondominant insular lobe according to surgical approach. Cognitive domain Surgical approach Pre-op Post-op day 7 Week 4 Month 3 Year 1 Memory Transsylvian–transinsular (n=9) 2 (22.2%) 4 (44.4%) 3 (33.3%) 2 (22.2%) 1 (11.1%) Transfrontal (n=5) 1 (20%) 1 (20%) 1 (20%) 0 (0%) 0 (0%) Transtemporal (n=3) 1 (33.3%) 2 (66.7%) 2 (66.7%) 1 (33.3%) 1 (33.3%) Combined approach (n=2) 1 (50%) 2 (100%) 2 (100%) 1 (50%) 1 (50%) Attention / Executive Transsylvian–transinsular (n=9) 3 (33.3%) 4 (44.4%) 4 (44.4%) 3 (33.3%) 2 (22.2%) Transfrontal (n=5) 1 (20%) 1 (20%) 1 (20%) 1 (20%) 1 (20%) Transtemporal (n=3) 1 (33.3%) 2 (66.7%) 2 (66.7%) 1 (33.3%) 1 (33.3%) Combined approach (n=2) 1 (50%) 2 (100%) 2 (100%) 2 (100%) 2 (100%) Visuospatial / Praxis Transsylvian–transinsular (n=9) 1 (11.1%) 2 (22.2%) 2 (22.2%) 1 (11.1%) 1 (11.1%) Transfrontal (n=5) 0 (0%) 1 (20%) 0 (0%) 0 (0%) 0 (0%) Transtemporal (n=3) 1 (33.3%) 1 (33.3%) 1 (33.3%) 1 (33.3%) 0 (0%) Combined approach (n=2) 1 (50%) 2 (100%) 2 (100%) 1 (50%) 1 (50%) ≥1 cognitive domain impaired Transsylvian–transinsular (n=9) 3 (33.3%) 6 (66.7%) 5 (55.6%) 4 (44.4%) 3 (33.3%) Transfrontal (n=5) 2 (40%) 2 (40%) 2 (40%) 1 (20%) 1 (20%) Transtemporal (n=3) 2 (66.7%) 3 (100%) 3 (100%) 2 (66.7%) 1 (33.3%) Combined approach (n=2) 1 (50%) 2 (100%) 2 (100%) 2 (100%) 2 (100%) Histopathological findings Histological examination of tumor tissue in all 31 patients confirmed the diagnosis of diffuse gliomas in accordance with the World Health Organization (WHO) classification. Low-grade gliomas (LGG) were identified in 19 patients, whereas high-grade gliomas (HGG) were diagnosed in 12 patients. Astrocytic variants predominated in the histological structure of the tumors, which is consistent with data from large international series on insular gliomas. In the illustrative clinical case, histological analysis revealed a fibrillary astrocytoma, correlating with the prolonged preclinical course of the disease and the findings of preoperative neuroimaging (fig. 7). Summary of functional outcomes Thus, despite the absence of persistent clinical neurological deficits after surgery, neuropsychological assessment enabled the identification of cognitive changes in a subset of patients, including those who were clinically intact. All transient neurological disturbances fully resolved, and postoperative neuroimaging revealed no ischemic or hemorrhagic complications. DISCUSSION This prospective single-center study demonstrates that the absence of persistent postoperative neurological deficits after surgical treatment of insular gliomas—particularly those located in the dominant hemisphere—does not preclude the presence of clinically relevant neuropsychological impairments. Despite favorable neurological and epileptological outcomes associated with the transsylvian–transinsular approach and awake surgery, systematic neuropsychological evaluation revealed a high prevalence of subclinical cognitive changes, predominantly affecting language, executive, and mnemonic functions. Neurological preservation and cognitive vulnerability The neurological outcomes obtained in the present study are consistent with data from large series reporting a low incidence of permanent motor and speech deficits after resection of insular gliomas when modern microsurgical techniques and function-oriented strategies are employed [ 9 , 24 , 33 , 38 ]. However, in contrast to most published studies that primarily focus on overt neurological outcomes, our findings demonstrate a pronounced dissociation between a clinically intact neurological status and impairment of higher cognitive functions. Even in patients without persistent motor or speech deficits, neuropsychological testing revealed abnormalities in one or more cognitive domains. These findings underscore the vulnerability of distributed cortico-subcortical networks involved in attention, executive control, and memory—functions that are not routinely assessed during standard neurological examination. Similar observations have previously been reported only sporadically and mainly in the context of awake surgery [ 10 , 13 , 37 ], whereas systematic evaluation of neuropsychological outcomes following the transsylvian–transinsular approach remains limited. Dominant hemisphere and domain-specific effects The most pronounced and persistent neuropsychological changes in our series were observed in patients with tumors involving the dominant hemisphere. Language and executive functions were the most vulnerable domains, in accordance with current concepts of the insula as a key hub within perisylvian language and associative networks [ 2 , 11 , 16 ]. Although partial regression of cognitive impairments was noted during follow-up, deficits persisted for up to one year in a subset of patients, indicating limited compensatory capacity of these functional systems. Awake surgery allowed minimization of clinically evident speech disturbances, corroborating the findings of Duffau et al. [ 12 , 13 ]. Nevertheless, despite preserved spontaneous speech, impairments in executive and mnemonic domains were detected in some patients. This suggests that focal language mapping, while effective in preventing overt aphasic deficits, does not fully protect broader cognitive networks. Surgical approach and functional trade-offs In our series, the transsylvian–transinsular approach demonstrated high neurological safety and satisfactory seizure control, in line with reports by other authors [ 32 , 33 , 43 ]. However, early neuropsychological impairments were observed in the majority of patients, and complete recovery was not universal, indicating the presence of functional trade-offs even with anatomically sparing approaches. In the nondominant hemisphere, cognitive changes were generally less pronounced but were absent only when limited surgical approaches were employed. The most unfavorable neuropsychological outcomes were associated with combined approaches, likely reflecting more extensive involvement of cortical and subcortical associative pathways and a greater length of the surgical corridor [ 27 , 36 ]. Seizure control and cognitive outcomes Surgical treatment in the present series achieved a high level of seizure control, consistent with the literature [ 31 , 47 , 50 ]. However, attainment of a favorable epileptological outcome (Engel class I) was not necessarily accompanied by preservation of cognitive function. Thus, epileptological success cannot be considered a surrogate marker of full functional recovery, particularly in tumors located within functionally eloquent regions. Pathophysiological considerations The illustrative clinical case in our study highlights the potential role of venous factors in the development of transient functional disturbances. The temporal association between injury to a small cortical vein in the perisylvian region and the occurrence of transient motor aphasia—despite the absence of arterial ischemia on postoperative neuroimaging—suggests a possible venous mechanism contributing to functional vulnerability. Similar anatomical and clinical observations have previously been emphasized in studies addressing venous drainage of the insular region [ 3 , 21 , 26 ]. Nevertheless, it should be emphasized that a definitive causal relationship cannot be established within the framework of the present study. LIMITATIONS AND CLINICAL IMPLICATIONS Study limitations The present study has several limitations. First, it was conducted at a single center and included a limited number of patients with dominant-hemisphere involvement, which restricts the scope of statistical analysis. Second, functional lateralization was determined clinically based on handedness, without mandatory use of functional MRI or the Wada test, which does not exclude atypical organization of language networks. Third, the neuropsychological analysis was descriptive and exploratory in nature, without the construction of multivariate models. Finally, any pathophysiological interpretations, including the proposed role of venous factors, are based on associative observations. Clinical implications The findings of this study have important practical implications. Neuropsychological testing should be considered an essential component of functional outcome assessment after surgical treatment of insular gliomas, even in the absence of clinically overt neurological deficits. During preoperative planning and intraoperative mapping, it is advisable to take into account not only motor and language functions but also executive and mnemonic domains. In addition, preoperative patient counseling should include discussion of the risk of subclinical cognitive changes. In the future, integration of functional neuroimaging and cognitive rehabilitation programs may contribute to improved long-term functional outcomes. CONCLUSION The present study demonstrates that in the surgical treatment of insular gliomas—particularly those located in the dominant hemisphere—the absence of persistent neurological deficits and the achievement of favorable seizure control are not equivalent to preservation of higher cognitive functions. Even when function-oriented strategies are employed, including the transsylvian–transinsular approach and awake surgery, a substantial proportion of patients exhibit subclinical and, in some cases, persistent neuropsychological impairments, predominantly affecting language and executive domains. These findings highlight the limitations of standard neurological examination as the sole tool for assessing functional outcomes and support the need for systematic incorporation of neuropsychological testing into pre- and postoperative follow-up protocols. A comprehensive functional approach that integrates cognitive aspects should be regarded as a key element in evaluating the results of surgical treatment of insular gliomas and in further refinement of neurosurgical strategies. Declarations Funding The authors received no financial support for the research, authorship, and/or publication of this article. Ethics approval and consent to participate The study protocol was approved by the local institutional ethics committee of the Republican Specialized Scientific and Practical Medical Center of Neurosurgery (Tashkent, Uzbekistan) and was conducted in accordance with the Declaration of Helsinki (2013 revision). Written informed consent was obtained from all participants prior to inclusion in the study. All patients were evaluated preoperatively and were deemed capable of ethically and medically providing informed consent for participation in the research. Consent for publication Written informed consent for publication of clinical details and clinical images was obtained from all patients included in this study. In cases where patients had cognitive impairment or lacked full decision-making capacity, written informed consent for publication was obtained from their family members or legal guardians. Data availability All data generated or analyzed during this study are included in this published article . Competing interests The authors declare that they have no competing interests. Author Contribution J.Y. conceived and designed the study. J.Y., U.A., and G.K. contributed to patient management, data collection, and clinical evaluation. J.Y. performed the surgical procedures and supervised the study. A.C. contributed to conceptual development, interpretation of results, and critical revision of the manuscript for important intellectual content. J.Y. drafted the main manuscript text. 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J Neurosurg. 2022:1–12. https://doi.org/10.3171/2022.8.JNS221067 Zhuang DX, Wu JS, Yao CJ, et al. Intraoperative multi-information-guided resection of dominant-sided insular gliomas in a 3-T intraoperative MRI integrated neurosurgical suite. World Neurosurg. 2016;89:84–92. https://doi.org/10.1016/j.wneu.2016.01.067 Simon M, Hagemann A, Gajadin S, et al. Surgical treatment for insular gliomas: a systematic review and meta-analysis. Brain Spine. 2024;4:102828. https://doi.org/10.1016/j.bas.2024.102828 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9006163","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":606265173,"identity":"7b5f8b1a-8ccb-4e18-be9b-544da3ee46c9","order_by":0,"name":"Jakhongirmirzo 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\u003cem\u003e\u003cstrong\u003e(b).\u003c/strong\u003e\u003c/em\u003eCoronal T1-weighted image: absence of gross structural deformation and clinically significant compression of the surrounding brain regions \u003cem\u003e\u003cstrong\u003e(c).\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-9006163/v1/7d84f814e5a6cd753744ffe6.png"},{"id":104874490,"identity":"22ea6642-a5aa-42d9-8874-f95b23bbd947","added_by":"auto","created_at":"2026-03-18 08:31:36","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":496458,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePreoperative contrast-enhanced brain MRI. \u003c/strong\u003eSagittal T2-weighted image: a tumor of the left insular region with medial extension \u003cem\u003e\u003cstrong\u003e(a).\u003c/strong\u003e\u003c/em\u003eAxial T2-weighted image: glioma of the left dominant insular lobe involving deep regions without a pronounced mass effect \u003cem\u003e\u003cstrong\u003e(b).\u003c/strong\u003e\u003c/em\u003e Coronal T1-weighted image: topographic relationship between the tumor and adjacent subcortical structures \u003cem\u003e\u003cstrong\u003e(c).\u003c/strong\u003e\u003c/em\u003e Sagittal contrast-enhanced T1-weighted image: absence of clear signs of intense contrast enhancement \u003cem\u003e\u003cstrong\u003e(d).\u003c/strong\u003e\u003c/em\u003e Axial contrast-enhanced T1-weighted image: heterogeneous contrast enhancement pattern of the tumor \u003cem\u003e\u003cstrong\u003e(e).\u003c/strong\u003e\u003c/em\u003e Coronal contrast-enhanced T1-weighted image: confirmation of medial tumor extension without evidence of gross infiltration of the surrounding structures \u003cem\u003e\u003cstrong\u003e(f).\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-9006163/v1/ae439788522cbb106dd6dd70.png"},{"id":104874487,"identity":"3498b6bc-e564-494d-83b5-698a2bdd10f7","added_by":"auto","created_at":"2026-03-18 08:31:36","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":661433,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePreoperative 3D time-of-flight (3D-TOF) MR angiography and diffusion tensor imaging (DTI). \u003c/strong\u003e3D-TOF MR angiography, lateral view: visualization of the major arterial vessels without signs of compression or tumor invasion \u003cem\u003e\u003cstrong\u003e(a).\u003c/strong\u003e\u003c/em\u003e 3D-TOF MR angiography, axial view: preserved configuration of the arterial circle of the brain base and its branches \u003cem\u003e\u003cstrong\u003e(b).\u003c/strong\u003e\u003c/em\u003e 3D-TOF MR angiography, frontal view: absence of stenosis or displacement of major arterial structures \u003cem\u003e\u003cstrong\u003e(c).\u003c/strong\u003e\u003c/em\u003eDTI tractography, sagittal view: displacement of white matter tracts within the zone of tumor growth with preserved tract integrity \u003cem\u003e\u003cstrong\u003e(d).\u003c/strong\u003e\u003c/em\u003e DTI tractography, oblique view: relationship between the tumor and adjacent subcortical tracts without evidence of tract destruction \u003cem\u003e\u003cstrong\u003e(e). \u003c/strong\u003e\u003c/em\u003eDTI tractography, alternative view: spatial displacement of fibers in the region of the left dominant insular lobe \u003cem\u003e\u003cstrong\u003e(f).\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-9006163/v1/cf8a4d6866147d67d1d0ac85.png"},{"id":105034061,"identity":"12368c10-585e-4434-b9d7-94b66af27b5a","added_by":"auto","created_at":"2026-03-20 07:22:34","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":888411,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eIntraoperative stages of the transsylvian–transinsular approach. \u003c/strong\u003eInitial stage of microsurgical dissection of the Sylvian fissure with visualization of the cortical surface and superficial venous structures \u003cem\u003e\u003cstrong\u003e(a).\u003c/strong\u003e\u003c/em\u003e Continuation of Sylvian fissure dissection; the arrow indicates a small cortical vein in the perisylvian region \u003cem\u003e\u003cstrong\u003e(b).\u003c/strong\u003e\u003c/em\u003e Formation of the transinsular surgical corridor with exposure of tumor tissue; the arrow marks the zone of venous relationships \u003cem\u003e\u003cstrong\u003e(c).\u003c/strong\u003e\u003c/em\u003eMagnified view of the perisylvian region: injury to a small cortical vein (arrow) during microsurgical manipulation \u003cem\u003e\u003cstrong\u003e(d).\u003c/strong\u003e\u003c/em\u003e Tumor resection stage through the established transinsular approach with visualization of the resection cavity \u003cem\u003e\u003cstrong\u003e(e).\u003c/strong\u003e\u003c/em\u003e Final intraoperative view after tumor removal, showing hemostasis and coverage of the resection cavity with hemostatic material \u003cem\u003e\u003cstrong\u003e(f).\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-9006163/v1/6886f524f8a69f8881eeedda.png"},{"id":104874492,"identity":"8fbf83ad-c41c-40f4-8d9f-c3a456e3e6eb","added_by":"auto","created_at":"2026-03-18 08:31:36","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":317611,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePostoperative brain computed tomography \u003c/strong\u003e\u003cem\u003e\u003cstrong\u003e(postoperative day 1).\u003c/strong\u003e\u003c/em\u003e\u003cstrong\u003e \u003c/strong\u003eSagittal CT reconstruction: visualization of the resection cavity in the projection of the left insular region without signs of acute hemorrhage \u003cem\u003e\u003cstrong\u003e(a).\u003c/strong\u003e\u003c/em\u003e Axial CT slice: postoperative resection cavity with mild pneumocephalus, without evidence of mass effect or compression of surrounding structures \u003cem\u003e\u003cstrong\u003e(b). \u003c/strong\u003e\u003c/em\u003eCoronal CT reconstruction: absence of intraparenchymal hemorrhage and significant cerebral edema in the surgical field \u003cem\u003e\u003cstrong\u003e(c).\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-9006163/v1/153fcd78a574dff47ad124c7.png"},{"id":104874491,"identity":"b622c247-8666-4091-8919-fddfe683cd06","added_by":"auto","created_at":"2026-03-18 08:31:36","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":513005,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePostoperative contrast-enhanced brain MRI. Sagittal T2-weighted image: \u003c/strong\u003epostoperative resection cavity in the projection of the left insular region without signs of marked perifocal edema \u003cem\u003e\u003cstrong\u003e(a).\u003c/strong\u003e\u003c/em\u003e Axial T2-weighted image: clear visualization of the resection cavity without evidence of mass effect or compression of adjacent structures \u003cem\u003e\u003cstrong\u003e(b).\u003c/strong\u003e\u003c/em\u003e Coronal T1-weighted image: anatomical relationship between the resection zone and subcortical structures after tumor removal \u003cem\u003e\u003cstrong\u003e(c).\u003c/strong\u003e\u003c/em\u003e Sagittal contrast-enhanced T1-weighted image: absence of pathological contrast enhancement within the resection area \u003cem\u003e\u003cstrong\u003e(d).\u003c/strong\u003e\u003c/em\u003eAxial contrast-enhanced T1-weighted image: confirmation of the achieved extent of resection with no evidence of residual tumor tissue \u003cem\u003e\u003cstrong\u003e(e). \u003c/strong\u003e\u003c/em\u003eCoronal contrast-enhanced T1-weighted image: absence of ischemic or hemorrhagic changes in the adjacent cortical and subcortical regions \u003cem\u003e\u003cstrong\u003e(f).\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-9006163/v1/26dd8aa3c16dcac763e6b827.png"},{"id":104874489,"identity":"3b4537f9-d246-4f6e-9dc9-aadc071a9ddf","added_by":"auto","created_at":"2026-03-18 08:31:36","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":1428765,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eMicroscopic appearance of a fibrillary astrocytoma (WHO Grade II). \u003c/strong\u003eThe histological section demonstrates astrocytic tumor cells within a fibrillary matrix, with moderate nuclear atypia and absence of necrosis and microvascular proliferation (hematoxylin and eosin staining).\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-9006163/v1/00db4adfbe46f8ac7d1e2839.png"},{"id":106960917,"identity":"34c8d9c7-9ae3-47ab-b48e-840de6959211","added_by":"auto","created_at":"2026-04-15 09:23:36","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":8367616,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9006163/v1/e1fcbc8e-fc21-4d62-9caf-d8382ae6f7b8.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eNeuropsychological Outcomes After Insular Tumor Resection: Focus on Neurologically Intact Patients Following Transsylvian–Transinsular Resection in the Dominant Hemisphere\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eInsular gliomas are among the most challenging tumors to treat surgically due to their deep-seated location, close anatomical relationships with cortical and subcortical functional networks, and marked variability of the vascular architecture [\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. The insula constitutes a key component of the limbic and paralimbic systems and plays an essential role in the regulation of language, executive, affective, and integrative cognitive functions [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Historically, the high rate of postoperative complications led to a cautious attitude toward aggressive surgical management of tumors in this region, particularly when located in the dominant hemisphere [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e, \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAdvances in microsurgical techniques, improved understanding of the topographic and microanatomy of the insular region, and the introduction of functionally oriented surgical concepts have substantially changed the management of insular gliomas [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Contemporary clinical series demonstrate that, with careful patient selection and appropriate choice of surgical approach, a meaningful extent of resection can be achieved with an acceptable rate of neurological morbidity [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]. In this context, the transsylvian\u0026ndash;transinsular approach is regarded as an anatomically sound corridor to insular tumors, allowing minimization of cortical injury while providing direct visualization of vascular and subcortical structures [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e, \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e, \u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e48\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDespite their location within the dominant hemisphere, insular gliomas frequently present without clinically evident neurological deficits [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. This phenomenon has been attributed both to the slow-growing nature of these tumors, enabling functional reorganization, and to the distributed organization of language and cognitive networks [\u003cspan additionalcitationids=\"CR11\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. As a result, standard neurological examination may fail to detect functional impairment even when eloquent structures are involved, thereby limiting its sensitivity for assessing functional outcomes after surgical treatment [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn recent years, increasing attention has been directed toward neuropsychological methods as more sensitive tools for the evaluation of higher cortical functions [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e, \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e, \u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e]. Neuropsychological testing allows the detection of subclinical cognitive impairments that are not identified during routine neurological examination but may significantly affect daily functioning and quality of life [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e, \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e]. Nevertheless, data on neuropsychological outcomes following resection of dominant insular gliomas remain limited, as most published studies primarily focus on gross neurological complications, extent of resection, and oncological outcomes [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e, \u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e52\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTransient postoperative disturbances, including motor and language deficits, warrant particular attention, as their underlying pathophysiological mechanisms remain incompletely understood [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e, \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e]. In addition to direct cortical or subcortical injury, increasing emphasis has been placed on venous factors, especially in the perisylvian region, where even minor disturbances of venous drainage may result in reversible functional deficits [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e, \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e]. Analysis of such clinical scenarios requires integration of intraoperative findings, neuroimaging data, and functional outcomes.\u003c/p\u003e \u003cp\u003eIn light of these considerations, a comprehensive approach to the evaluation of functional outcomes after surgical treatment of dominant insular gliomas appears warranted, incorporating not only standard neurological examination but also systematic neuropsychological assessment [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e, \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e49\u003c/span\u003e, \u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e]. The present study aims to analyze neuropsychological outcomes in patients with dominant insular gliomas following surgical treatment, with an in-depth functional analysis of the subgroup undergoing resection via the transsylvian\u0026ndash;transinsular approach and a particular focus on identifying subclinical cognitive impairments in the absence of clinically significant neurological deficits.\u003c/p\u003e"},{"header":"MATERIALS AND METHODS","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy Design and Ethical Considerations\u003c/h2\u003e \u003cp\u003eA prospective observational cohort study was conducted at a single specialized neurosurgical center\u0026mdash;the Republican Specialized Scientific and Practical Medical Center of Neurosurgery (Tashkent, Uzbekistan). The study protocol was approved by the local institutional ethics committee and was conducted in accordance with the ethical principles of the Declaration of Helsinki (2013 revision). Written informed consent for surgical treatment and the use of clinical data for research purposes was obtained from all patients prior to inclusion in the study.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003ePatient Characteristics\u003c/h3\u003e\n\u003cp\u003eBetween January 2023 and December 2025, a total of 31 patients with insular gliomas who underwent surgical treatment were prospectively evaluated. In 12 patients, the tumor was located in the dominant insular lobe. Among them, 8 patients underwent tumor resection using the transsylvian\u0026ndash;transinsular approach, and this subgroup constituted the primary study cohort \u003cb\u003e(table. 1).\u003c/b\u003e\u003c/p\u003e \u003cp\u003ePatients with a clinically preserved preoperative neurological status were included, allowing standardized neuropsychological assessment. Patients with significant preoperative neurological deficits that could compromise the reliability of cognitive evaluation were excluded from the neuropsychological outcome analysis.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eClinical, Demographic, and Surgical Characteristics of Patients with Insular Tumors According to Hemispheric Dominance.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"9\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"9\" nameend=\"c9\" namest=\"c1\"\u003e \u003cp\u003e\u003cem\u003eN o n - D o m i n a n t\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003e№\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSide\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eKPS Score\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eEducation\u003c/p\u003e \u003cp\u003elevel\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLocation\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eApproach\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR/GT\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eWHO Grade\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMedial extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMedial extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePure insular\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePure insular\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePure insular\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eGT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLateral extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eIII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePure insular\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMedial extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePure insular\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLateral extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-F\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eGT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLateral extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-F\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eGT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLateral extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-F\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eGT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLateral extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-F\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eIII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLateral extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-F\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eGT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eIII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLateral extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLateral extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLateral extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eGT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMultiregional\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCombined\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eIII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMultiregional\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCombined\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eIII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"9\" nameend=\"c9\" namest=\"c1\"\u003e \u003cp\u003e\u003cem\u003eD o m i n a n t\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePure insular\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePure insular\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eGT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMedial extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMedial extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eIII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePure insular\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eGT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePure insular\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eLt\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e100\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e3\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eMedial extension\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003eT-T\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003eSTR\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003eII\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePure insular\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLateral extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eTO\u0026thinsp;+\u0026thinsp;AS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLateral extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eTO\u0026thinsp;+\u0026thinsp;AS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLateral extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eTO\u0026thinsp;+\u0026thinsp;AS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eGT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLateral extension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eTO\u0026thinsp;+\u0026thinsp;AS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSTR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eIII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e\n\u003ch3\u003eDetermination of the Dominant Hemisphere\u003c/h3\u003e\n\u003cp\u003eThe dominant hemisphere was determined clinically based on handedness, in accordance with widely accepted clinical practice. Only patients with clearly identifiable hemispheric dominance were included in the analysis, allowing reliable interpretation of functional and neuropsychological outcomes.\u003c/p\u003e\n\u003ch3\u003ePreoperative Neuroimaging\u003c/h3\u003e\n\u003cp\u003eAll patients underwent a standardized preoperative neuroimaging protocol, including contrast-enhanced brain MRI (T1-weighted images), T2- and FLAIR-weighted sequences, diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), and MR angiography using a 3D time-of-flight (3D-TOF) technique. The acquired imaging data were used for anatomical tumor assessment, surgical approach planning, and evaluation of the relationships between the lesion and adjacent vascular and subcortical structures.\u003c/p\u003e\n\u003ch3\u003eSurgical Technique\u003c/h3\u003e\n\u003cp\u003eSurgical procedures were performed using two anesthetic protocols depending on the selected surgical strategy. Resections carried out via the transsylvian\u0026ndash;transinsular approach were performed under general anesthesia, whereas patients operated on under awake conditions underwent an awake craniotomy protocol with intraoperative language mapping. Among the 12 patients with dominant insular gliomas, tumor resection was performed via the transsylvian\u0026ndash;transinsular approach in 8 patients and using awake craniotomy in 4 patients.\u003c/p\u003e \u003cp\u003eFor the transsylvian\u0026ndash;transinsular approach, microsurgical dissection of the Sylvian fissure was performed without cortical incision. Depending on tumor location and individual vascular anatomy, two dissection trajectories were employed: a medial-to-lateral approach in 5 patients and a lateral-to-medial approach in 3 patients.\u003c/p\u003e \u003cp\u003eIn patients with tumors located in the non-dominant hemisphere, the choice of surgical approach was determined by tumor location, extent, and relationships with cortical and subcortical structures. According to anatomical characteristics, the following approaches were used: transsylvian\u0026ndash;transinsular (n\u0026thinsp;=\u0026thinsp;9), transfrontal (n\u0026thinsp;=\u0026thinsp;5), transtemporal (n\u0026thinsp;=\u0026thinsp;3), and combined approaches (n\u0026thinsp;=\u0026thinsp;2). All procedures in this group were performed under general anesthesia in accordance with the principles of functionally oriented microsurgery.\u003c/p\u003e \u003cp\u003eIn all procedures performed via the transsylvian\u0026ndash;transinsular approach, intraoperative neurophysiological monitoring with motor evoked potential (MEP) recording was utilized to assess the functional integrity of subcortical motor pathways. Neuronavigation was not employed; instead, individualized preoperative three-dimensional planning based on neuroimaging data was used to define optimal surgical corridors and to evaluate the relationships between the tumor and adjacent vascular and subcortical structures.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eAssessment of the Extent of Resection\u003c/h2\u003e \u003cp\u003eThe extent of tumor resection was assessed based on early postoperative contrast-enhanced MRI performed on the second postoperative day. Gross total resection (GTR) was defined as the absence of residual tumor on postoperative neuroimaging, whereas subtotal resection (STR) was recorded when residual tumor tissue was present.\u003c/p\u003e \u003cp\u003eWithin the subgroup of patients with dominant insular gliomas, subtotal resection was achieved in 9 patients, including 6 cases treated via the transsylvian\u0026ndash;transinsular approach, while gross total resection was achieved in 3 patients, 2 of whom underwent surgery using the transsylvian\u0026ndash;transinsular approach.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003ePostoperative Neuroimaging\u003c/h3\u003e\n\u003cp\u003eAll patients underwent non-contrast computed tomography of the brain within the first postoperative day to exclude hemorrhagic complications. Follow-up contrast-enhanced MRI was performed on the second postoperative day to assess the extent of resection and to identify ischemic or structural changes.\u003c/p\u003e\n\u003ch3\u003eNeurological Assessment\u003c/h3\u003e\n\u003cp\u003eNeurological status was assessed preoperatively, in the early postoperative period, and during follow-up. New neurological deficits were defined as impairments not present in the preoperative period. Transient and permanent neurological deficits were analyzed separately.\u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eNeuropsychological Assessment\u003c/h2\u003e \u003cp\u003eNeuropsychological assessment was performed in all patients during the preoperative and postoperative periods using standardized and validated test batteries aimed at evaluating language functions, executive functions, attention, and memory, in accordance with international recommendations. Assessment of language functions included naming and verbal productivity tasks, such as the Boston Naming Test and tests of phonemic and semantic verbal fluency. Executive functions and attention were evaluated using the Trail Making Test (parts A and B) and tasks assessing cognitive control, whereas memory was examined using the Digit Span (forward and backward) and verbal memory tests. Neuropsychological testing was conducted at standardized follow-up time points; in patients with transient speech disturbances, repeat assessment was performed after clinical resolution of aphasia.\u003c/p\u003e \u003cp\u003ePostoperative testing was carried out under conditions of stable clinical status. In a patient with transient motor aphasia, neuropsychological assessment was performed only after complete resolution of the speech deficit. In patients with a history of epileptic seizures, testing was conducted during the interictal period; assessment was postponed in the presence of recent seizures or postictal symptoms.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eGiven the exploratory nature of the study, the limited sample size, and the primarily descriptive focus of the analysis, statistical data processing was predominantly descriptive. Quantitative variables are presented as means or medians with corresponding ranges, whereas qualitative data are reported as absolute values and percentages. Formal statistical comparisons and hypothesis testing were not performed, as the aim of the study was to identify general trends and patterns of functional changes rather than to establish causal relationships.\u003c/p\u003e \u003c/div\u003e"},{"header":"RESULTS","content":"\u003cp\u003e\u003cstrong\u003eOverall cohort characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the studied prospective series of 31 patients, the tumor was localized in the dominant insular lobe in 12 patients. Within this subgroup, surgical intervention was performed using a transsylvian\u0026ndash;transinsular approach in 8 patients; these patients were included in the analysis of neuropsychological outcomes. Preoperatively, the neurological status of all patients in this subgroup was assessed as clinically intact.\u003c/p\u003e\n\u003cp\u003eIn the early postoperative period, motor deficits were observed in two patients, and one patient developed transient motor aphasia. In all cases, these neurological disturbances were temporary and fully resolved during subsequent follow-up. Compared with the preoperative condition, no new permanent neurological deficits were identified.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eIllustrative clinical case\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAs an illustrative clinical case, we present a patient with a tumor of the left (dominant) insular region, selected based on a combination of anatomical and clinico-radiological characteristics as well as specific features of the intraoperative course. The tumor demonstrated predominantly medial growth from the insular lobe with close proximity to subcortical structures, which determined the high functional relevance of the surgical intervention.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe patient was followed dynamically for two years; according to MRI performed 2 years and 4 months prior to surgery, a slowly progressive tumor lesion was identified, without a pronounced mass effect and in the absence of a clinically significant neurological deficit \u003cstrong\u003e\u003cem\u003e(fig. 1).\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis case was also selected because of an intraoperative technical particularity\u0026mdash;injury to a small cortical vein during dissection of the Sylvian fissure. In the remaining cases of the studied series, no intraoperative technical complications were observed. The presented case illustrates the potential challenges of microsurgical dissection in the perisylvian region and emphasizes the importance of detailed analysis of venous anatomy when performing a transsylvian\u0026ndash;transinsular approach\u003c/p\u003e\n\u003cp\u003ePreoperative contrast-enhanced magnetic resonance imaging revealed a tumor of the insular region with predominantly medial extension, spreading toward the subcortical structures without clear evidence of their gross infiltration. The lesion was characterized by a heterogeneous structure and well-visualized margins on T2- and FLAIR-weighted sequences, while no marked mass effect or compression of the surrounding anatomical structures was observed. The relationships between the tumor and the adjacent subcortical white matter tracts and vascular structures were considered close, which was of critical importance for planning the surgical approach \u003cstrong\u003e\u003cem\u003e(fig. 2).\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAccording to 3D time-of-flight (3D-TOF) MR angiography, the major intracranial arterial structures were clearly visualized, without evidence of compression, stenosis, or tumor invasion, indicating preservation of the primary arterial blood supply within the affected region.\u003c/p\u003e\n\u003cp\u003eDiffusion tensor imaging (DTI) demonstrated displacement of the adjacent white matter tracts as a result of the tumor-related mass effect, while their structural integrity was preserved, with no signs of tract disruption or marked fiber destruction. These findings were of key importance for the selection of the surgical strategy and for planning a safe transsylvian\u0026ndash;transinsular approach \u003cstrong\u003e\u003cem\u003e(fig. 3).\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eIntraoperative findings\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTumor resection was performed via a transsylvian\u0026ndash;transinsular approach. Microsurgical dissection of the Sylvian fissure enabled the creation of a direct corridor to the lesion without the need for a cortical incision.\u003c/p\u003e\n\u003cp\u003eDuring surgery, injury to a small cortical vein in the perisylvian region was noted \u003cstrong\u003e\u003cem\u003e(fig. 4).\u003c/em\u003e\u003c/strong\u003e No arterial injuries were recorded. The tumor was removed within the preplanned extent while preserving the subcortical structures. Intraoperative neurophysiological monitoring with motor evoked potentials was employed during the resection phase, including subcortical stimulation. As functionally eloquent white matter pathways were approached, responses to subcortical stimulation were elicited, indicating close proximity of the motor tracts and serving as the basis for terminating further resection in that direction. Consequently, the extent of resection was limited by functional boundaries, allowing achievement of the planned resection volume without injury to the subcortical white matter tracts (subcortical stimulation threshold \u0026le; 3\u0026ndash;5 mA; preservation of motor evoked potentials without significant amplitude or latency changes).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePostoperative imaging results\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePostoperative computed tomography performed within the first 24 hours after surgery revealed no evidence of intracranial hemorrhage or significant cerebral edema \u003cstrong\u003e\u003cem\u003e(fig. 5).\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eContrast-enhanced magnetic resonance imaging of the brain performed on the second postoperative day confirmed the achieved extent of resection, with no evidence of residual tumor tissue within the resection area. Additionally, no signs of ischemic changes, hemorrhagic complications, or pathological contrast enhancement were identified in the adjacent cortical or subcortical structures, indicating preservation of regional blood supply and functionally eloquent anatomical structures (fig. 6).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eNeurological and neuropsychological outcomes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the early postoperative period, two patients developed moderate motor deficits (up to 3 points on the MRC scale), which completely resolved within two weeks, whereas one patient developed transient motor aphasia without an associated motor deficit, with full recovery of speech function within five days of follow-up \u003cstrong\u003e\u003cem\u003e(table. 2).\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable. 2. Neurological outcomes after surgical treatment of insular gliomas according to hemispheric dominance and type of surgical approach.\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"661\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eOutcome\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eHemisphere\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eSurgical approach\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePre-op\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePost-op\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eday 3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePost-op\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eday 7\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeek 4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eMonth 3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eYear\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"6\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eMotor deficit\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eDominant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u003c/p\u003e\n \u003cp\u003etransinsular (n=8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (12.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (12.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 118px;\"\u003e\n \u003cp\u003eAwake\u003c/p\u003e\n \u003cp\u003esurgery (n=4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eNon-dominant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u0026ndash;transinsular (n=9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e(22.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e(22.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e(22.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(11.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(11.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 118px;\"\u003e\n \u003cp\u003eTransfrontal (n=5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 118px;\"\u003e\n \u003cp\u003eTranstemporal (n=3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 118px;\"\u003e\n \u003cp\u003eCombined approach (n=2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eLanguage deficit\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eDominant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u0026ndash;transinsular (n=8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(12.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 118px;\"\u003e\n \u003cp\u003eAwake\u003c/p\u003e\n \u003cp\u003eSurgery (n=4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003eNeuropsychological assessment performed after resolution of aphasia revealed subclinical cognitive changes that were not accompanied by clinically significant neurological deficits. The profile of the identified neuropsychological impairments did not fully correlate with the findings of standard neurological examination.\u003c/p\u003e\n\u003cp\u003ePreoperatively, seizure disorder was present in a subset of patients in both hemispheres. Following surgical treatment, a progressive reduction in seizure frequency was observed over the course of follow-up, with the most pronounced improvement at 3 months and 1 year after the intervention \u003cstrong\u003e\u003cem\u003e(table. 3).\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u003cstrong\u003eTable 3. Seizure outcomes before and after surgical treatment of insular gliomas according to hemisphere and surgical approach.\u003c/strong\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"664\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eHemisphere\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eSurgical approach\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePre-op\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePost-op day 3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePost-op day 7\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeek 4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eMonth 3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eYear 1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eDominant hemisphere\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eTranssylvian\u0026ndash;transinsular (n = 8)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003cp\u003e(75%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003cp\u003e(37.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (12.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (12.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eAwake surgery (n = 4)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003cp\u003e(75%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e(0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eNon-dominant hemisphere\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eTranssylvian\u0026ndash;transinsular (n = 9)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e5 (55.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003cp\u003e(33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e(22.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (22.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (11.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (11.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eTransfrontal (n = 5)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e(40%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e(0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e(0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e(0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eTranstemporal (n = 3)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (66.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e(0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCombined approach (n = 2)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e(100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e(100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAt 3 months after surgery, favorable seizure control (Engel class I) was achieved in the majority of patients, regardless of the affected hemisphere and the surgical approach used, with further improvement or stabilization of outcomes by 1 year of follow-up \u003cstrong\u003e\u003cem\u003e(table. 4).\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cstrong\u003eTable 4. Seizure control according to the Engel classification in the long-term period after resection of insular gliomas.\u003c/strong\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"665\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eHemisphere\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eSurgical approach\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eMonth 3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eYear 1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eDominant\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u0026ndash;transinsular (n = 8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003cp\u003e(87.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003cp\u003e(87.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eDominant\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eAwake surgery (n = 4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003cp\u003e(75%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003cp\u003e(100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eNon-dominant\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u0026ndash;transinsular (n = 9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003cp\u003e(88.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003cp\u003e(88.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eNon-dominant\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eOther approaches (n = 10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003cp\u003e(70%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003cp\u003e(80%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eIn patients with gliomas of the dominant insular lobe, neuropsychological impairments were already present in the preoperative period and demonstrated worsening in the early postoperative phase. Language, executive, and mnemonic functions were most frequently affected, with the greatest severity of deficits observed on postoperative day 7. Subsequently, a trend toward partial regression of cognitive disturbances was noted; however, in a substantial proportion of patients, impairment in at least one cognitive domain persisted even at 1 year of follow-up, despite the absence of clinically significant neurological deficits \u003cstrong\u003e\u003cem\u003e(table. 5).\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cstrong\u003eTable 5. Dynamics of neuropsychological impairments across cognitive domains in patients with gliomas of the dominant insular lobe.\u003c/strong\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"661\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCognitive domain\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eSurgical approach\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePre-op\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePost-op day 7\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeek 4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eMonth 3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eYear 1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eLanguage\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u0026ndash;transinsular (n=8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (12.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3 (37.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (12.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eAwake surgery (n=4)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(75%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eMemory\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u0026ndash;transinsular (n=8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e5\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(62.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3 (37.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eAwake surgery (n=4)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eAttention / Executive\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u0026ndash;transinsular (n=8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e6\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(75%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e5 (62.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3 (37.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eAwake surgery (n=4)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(75%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eVisuospatial / Praxis\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u0026ndash;transinsular (n=8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (12.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(37.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (12.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (12.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eAwake surgery (n=4)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026ge;1 cognitive domain impaired\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u0026ndash;transinsular (n=8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3 (37.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e7\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(87.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e6\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(75%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e5 (62.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eAwake surgery (n=4)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3 (75%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eIn patients with gliomas of the nondominant insular lobe, neuropsychological impairments were identified predominantly in the domains of memory, attention, and executive functions, with an increase in their frequency in the early postoperative period. The most pronounced and persistent cognitive changes were observed in patients operated on using transtemporal and combined approaches. Subsequently, partial regression of these impairments was noted; however, in a subset of patients, involvement of at least one cognitive domain persisted even at 1 year of follow-up, underscoring the functional significance of the nondominant insular region \u003cstrong\u003e\u003cem\u003e(table. 6).\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cstrong\u003eTable 6. Neuropsychological impairments across cognitive domains in patients with gliomas of the nondominant insular lobe according to surgical approach.\u0026nbsp;\u003c/strong\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"663\" class=\"fr-table-selection-hover\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCognitive domain\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eSurgical approach\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePre-op\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePost-op day 7\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeek 4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eMonth 3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eYear 1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eMemory\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u0026ndash;transinsular (n=9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (22.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(44.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (22.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (11.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTransfrontal (n=5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranstemporal (n=3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (66.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (66.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eCombined approach (n=2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eAttention / Executive\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u0026ndash;transinsular (n=9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4 (44.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4 (44.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (22.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTransfrontal (n=5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranstemporal (n=3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (66.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (66.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eCombined approach (n=2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eVisuospatial / Praxis\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u0026ndash;transinsular (n=9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (11.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (22.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (22.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (11.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (11.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTransfrontal (n=5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranstemporal (n=3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eCombined approach (n=2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026ge;1 cognitive domain impaired\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranssylvian\u0026ndash;transinsular (n=9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e6 (66.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e5 (55.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4 (44.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTransfrontal (n=5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (40%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (40%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (40%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTranstemporal (n=3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (66.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e3 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (66.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eCombined approach (n=2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e1 (50%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e2 (100%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eHistopathological findings\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHistological examination of tumor tissue in all 31 patients confirmed the diagnosis of diffuse gliomas in accordance with the World Health Organization (WHO) classification. Low-grade gliomas (LGG) were identified in 19 patients, whereas high-grade gliomas (HGG) were diagnosed in 12 patients. Astrocytic variants predominated in the histological structure of the tumors, which is consistent with data from large international series on insular gliomas. In the illustrative clinical case, histological analysis revealed a fibrillary astrocytoma, correlating with the prolonged preclinical course of the disease and the findings of preoperative neuroimaging \u003cstrong\u003e\u003cem\u003e(fig. 7).\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSummary of functional outcomes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThus, despite the absence of persistent clinical neurological deficits after surgery, neuropsychological assessment enabled the identification of cognitive changes in a subset of patients, including those who were clinically intact. All transient neurological disturbances fully resolved, and postoperative neuroimaging revealed no ischemic or hemorrhagic complications.\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eThis prospective single-center study demonstrates that the absence of persistent postoperative neurological deficits after surgical treatment of insular gliomas—particularly those located in the dominant hemisphere—does not preclude the presence of clinically relevant neuropsychological impairments. Despite favorable neurological and epileptological outcomes associated with the transsylvian–transinsular approach and awake surgery, systematic neuropsychological evaluation revealed a high prevalence of subclinical cognitive changes, predominantly affecting language, executive, and mnemonic functions.\u003c/p\u003e \u003cdiv id=\"Sec22\" class=\"Section2\"\u003e \u003ch2\u003eNeurological preservation and cognitive vulnerability\u003c/h2\u003e \u003cp\u003eThe neurological outcomes obtained in the present study are consistent with data from large series reporting a low incidence of permanent motor and speech deficits after resection of insular gliomas when modern microsurgical techniques and function-oriented strategies are employed [\u003cspan class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e33\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e38\u003c/span\u003e]. However, in contrast to most published studies that primarily focus on overt neurological outcomes, our findings demonstrate a pronounced dissociation between a clinically intact neurological status and impairment of higher cognitive functions.\u003c/p\u003e \u003cp\u003eEven in patients without persistent motor or speech deficits, neuropsychological testing revealed abnormalities in one or more cognitive domains. These findings underscore the vulnerability of distributed cortico-subcortical networks involved in attention, executive control, and memory—functions that are not routinely assessed during standard neurological examination. Similar observations have previously been reported only sporadically and mainly in the context of awake surgery [\u003cspan class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e37\u003c/span\u003e], whereas systematic evaluation of neuropsychological outcomes following the transsylvian–transinsular approach remains limited.\u003c/p\u003e \u003cdiv id=\"Sec23\" class=\"Section3\"\u003e \u003ch2\u003eDominant hemisphere and domain-specific effects\u003c/h2\u003e \u003cp\u003eThe most pronounced and persistent neuropsychological changes in our series were observed in patients with tumors involving the dominant hemisphere. Language and executive functions were the most vulnerable domains, in accordance with current concepts of the insula as a key hub within perisylvian language and associative networks [\u003cspan class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e16\u003c/span\u003e]. Although partial regression of cognitive impairments was noted during follow-up, deficits persisted for up to one year in a subset of patients, indicating limited compensatory capacity of these functional systems.\u003c/p\u003e \u003cp\u003eAwake surgery allowed minimization of clinically evident speech disturbances, corroborating the findings of Duffau et al. [\u003cspan class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e13\u003c/span\u003e]. Nevertheless, despite preserved spontaneous speech, impairments in executive and mnemonic domains were detected in some patients. This suggests that focal language mapping, while effective in preventing overt aphasic deficits, does not fully protect broader cognitive networks.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec24\" class=\"Section2\"\u003e \u003ch2\u003eSurgical approach and functional trade-offs\u003c/h2\u003e \u003cp\u003eIn our series, the transsylvian–transinsular approach demonstrated high neurological safety and satisfactory seizure control, in line with reports by other authors [\u003cspan class=\"CitationRef\"\u003e32\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e33\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e43\u003c/span\u003e]. However, early neuropsychological impairments were observed in the majority of patients, and complete recovery was not universal, indicating the presence of functional trade-offs even with anatomically sparing approaches.\u003c/p\u003e \u003cp\u003eIn the nondominant hemisphere, cognitive changes were generally less pronounced but were absent only when limited surgical approaches were employed. The most unfavorable neuropsychological outcomes were associated with combined approaches, likely reflecting more extensive involvement of cortical and subcortical associative pathways and a greater length of the surgical corridor [\u003cspan class=\"CitationRef\"\u003e27\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e36\u003c/span\u003e].\u003c/p\u003e \u003cdiv id=\"Sec25\" class=\"Section3\"\u003e \u003ch2\u003eSeizure control and cognitive outcomes\u003c/h2\u003e \u003cp\u003eSurgical treatment in the present series achieved a high level of seizure control, consistent with the literature [\u003cspan class=\"CitationRef\"\u003e31\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e47\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e50\u003c/span\u003e]. However, attainment of a favorable epileptological outcome (Engel class I) was not necessarily accompanied by preservation of cognitive function. Thus, epileptological success cannot be considered a surrogate marker of full functional recovery, particularly in tumors located within functionally eloquent regions.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec26\" class=\"Section3\"\u003e \u003ch2\u003ePathophysiological considerations\u003c/h2\u003e \u003cp\u003eThe illustrative clinical case in our study highlights the potential role of venous factors in the development of transient functional disturbances. The temporal association between injury to a small cortical vein in the perisylvian region and the occurrence of transient motor aphasia—despite the absence of arterial ischemia on postoperative neuroimaging—suggests a possible venous mechanism contributing to functional vulnerability. Similar anatomical and clinical observations have previously been emphasized in studies addressing venous drainage of the insular region [\u003cspan class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e26\u003c/span\u003e]. Nevertheless, it should be emphasized that a definitive causal relationship cannot be established within the framework of the present study.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec27\" class=\"Section3\"\u003e \u003cdiv id=\"Sec28\" class=\"Section4\"\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e "},{"header":"LIMITATIONS AND CLINICAL IMPLICATIONS","content":"\u003ch2\u003eStudy limitations\u003c/h2\u003e\u003cp\u003eThe present study has several limitations. First, it was conducted at a single center and included a limited number of patients with dominant-hemisphere involvement, which restricts the scope of statistical analysis. Second, functional lateralization was determined clinically based on handedness, without mandatory use of functional MRI or the Wada test, which does not exclude atypical organization of language networks. Third, the neuropsychological analysis was descriptive and exploratory in nature, without the construction of multivariate models. Finally, any pathophysiological interpretations, including the proposed role of venous factors, are based on associative observations.\u003c/p\u003e\u003ch2\u003eClinical implications\u003c/h2\u003e\u003cp\u003eThe findings of this study have important practical implications. Neuropsychological testing should be considered an essential component of functional outcome assessment after surgical treatment of insular gliomas, even in the absence of clinically overt neurological deficits. During preoperative planning and intraoperative mapping, it is advisable to take into account not only motor and language functions but also executive and mnemonic domains. In addition, preoperative patient counseling should include discussion of the risk of subclinical cognitive changes. In the future, integration of functional neuroimaging and cognitive rehabilitation programs may contribute to improved long-term functional outcomes.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eThe present study demonstrates that in the surgical treatment of insular gliomas\u0026mdash;particularly those located in the dominant hemisphere\u0026mdash;the absence of persistent neurological deficits and the achievement of favorable seizure control are not equivalent to preservation of higher cognitive functions. Even when function-oriented strategies are employed, including the transsylvian\u0026ndash;transinsular approach and awake surgery, a substantial proportion of patients exhibit subclinical and, in some cases, persistent neuropsychological impairments, predominantly affecting language and executive domains.\u003c/p\u003e \u003cp\u003eThese findings highlight the limitations of standard neurological examination as the sole tool for assessing functional outcomes and support the need for systematic incorporation of neuropsychological testing into pre- and postoperative follow-up protocols. A comprehensive functional approach that integrates cognitive aspects should be regarded as a key element in evaluating the results of surgical treatment of insular gliomas and in further refinement of neurosurgical strategies.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors received no financial support for the research, authorship, and/or publication of this article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study protocol was approved by the local institutional ethics committee of the Republican Specialized Scientific and Practical Medical Center of Neurosurgery (Tashkent, Uzbekistan) and was conducted in accordance with the Declaration of Helsinki (2013 revision). Written informed consent was obtained from all participants prior to inclusion in the study. All patients were evaluated preoperatively and were deemed capable of ethically and medically providing informed consent for participation in the research.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent for publication of clinical details and clinical images was obtained from all patients included in this study. In cases where patients had cognitive impairment or lacked full decision-making capacity, written informed consent for publication was obtained from their family members or legal guardians.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data generated or analyzed during this study are included in this published article\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eJ.Y. conceived and designed the study. J.Y., U.A., and G.K. contributed to patient management, data collection, and clinical evaluation. J.Y. performed the surgical procedures and supervised the study. A.C. contributed to conceptual development, interpretation of results, and critical revision of the manuscript for important intellectual content. J.Y. drafted the main manuscript text. All authors reviewed, edited, and approved the final version of the manuscript and agree to be accountable for all aspects of the work.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eYasargil MG, von Ammon K, Cavazos E, Doczi T, Reeves JD, Roth P. 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Surgical treatment for insular gliomas: a systematic review and meta-analysis. \u003cem\u003eBrain Spine.\u003c/em\u003e 2024;4:102828. https://doi.org/10.1016/j.bas.2024.102828\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-9006163/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9006163/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eGliomas of the dominant insular lobe represent functionally critical tumors in which overt neurological deficits may be absent despite involvement of language-related and associative networks. In such cases, standard neurological examination does not always adequately reflect the status of higher cognitive functions, underscoring the importance of neuropsychological assessment for a comprehensive evaluation of functional outcomes following surgical treatment.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObjective\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo evaluate neuropsychological outcomes in patients with gliomas of the dominant insular lobe, with particular emphasis on a functional analysis of the subgroup undergoing resection via the transsylvian–transinsular approach, aiming to identify subclinical cognitive alterations in the absence of clinically significant neurological deficits.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaterials and Methods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA prospective, single-center observational cohort study was conducted between January 2023 and December 2025. Thirty-one patients aged 18–52 years were included. Hemispheric dominance was determined clinically based on handedness. All tumors were classified as gliomas according to the WHO classification (LGG/HGG). In 12 patients, the tumor was located in the left insular lobe; among them, 8 patients underwent resection via the transsylvian–transinsular approach, which was applied in individuals with a clinically preserved preoperative neurological status allowing standardized neuropsychological assessment. The extent of resection comprised subtotal resection (STR) in 9 patients and gross total resection (GTR) in 3 patients. Neuropsychological evaluation was performed in all patients during the preoperative and postoperative periods; in patients with transient motor aphasia, testing was conducted after regression of the speech deficit. One illustrative clinical case is presented using intraoperative images.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the early postoperative period, transient neurological disturbances were observed in three patients with dominant insular tumors who underwent resection via the transsylvian–transinsular approach: motor deficits in two patients and motor aphasia in one patient. No new permanent neurological deficits were identified compared with the preoperative status, and all transient deficits completely resolved during follow-up.\u003c/p\u003e\n\u003cp\u003eNeuropsychological assessment revealed cognitive alterations in a subset of patients both in the early postoperative period and during subsequent follow-up, including patients with clinically preserved or recovered neurological status. The profile and severity of neuropsychological impairments varied across patients and time points, as detailed in the corresponding tables.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWithin the framework of this prospective study, it was demonstrated that a clinically preserved neurological status after surgical treatment of dominant insular gliomas does not necessarily reflect the integrity of higher cognitive functions. Despite the absence of permanent motor or language deficits, neuropsychological assessment identified cognitive alterations in a subset of patients, including those with an otherwise neurologically intact clinical presentation. In this context, neuropsychological testing proved to be more sensitive than standard neurological examination in detecting subclinical cognitive impairments following tumor resection via the transsylvian–transinsular approach.\u003c/p\u003e","manuscriptTitle":"Neuropsychological Outcomes After Insular Tumor Resection: Focus on Neurologically Intact Patients Following Transsylvian–Transinsular Resection in the Dominant Hemisphere","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-18 08:31:22","doi":"10.21203/rs.3.rs-9006163/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"f7cbe74a-38d8-474b-a2bb-784a5cceda03","owner":[],"postedDate":"March 18th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-04-14T21:54:34+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-18 08:31:22","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9006163","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9006163","identity":"rs-9006163","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}