A Comparison of Laminectomy and Hemilaminectomy Approaches for Resection of Spinal Schwannomas and Meningiomas

A Comparison of Laminectomy and Hemilaminectomy Approaches for Resection of Spinal Schwannomas and Meningiomas | 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 Article A Comparison of Laminectomy and Hemilaminectomy Approaches for Resection of Spinal Schwannomas and Meningiomas Mauro Dobran, Serena Vittoria Lisi, Denis Aiudi, Fabiola Cappella, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4685546/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: Spinal schwannomas and meningiomas are the most common spinal cord benign tumors in adults and total excision is the goal of the treatment. The traditional surgical approach is performed by total laminectomy, but recently unilateral hemilaminectomy has been recognized as a valuable surgical alternative. We report the clinical results of patients affected by spinal schwannoma and meningioma in whom total laminectomy or unilateral hemilaminectomy were performed. Material and Methods: A retrospective study of patients who underwent resection of spinal meningioma or schwannoma by laminectomy or unilateral hemilaminectomy approaches in our Institute from January 2013 to January 2023 was made. The baseline data of these patients, operative approach and postoperative outcome were compared. Results: The study was performed on 41 patients with mean age of 62.5 ±14.6 years. Our series included 24 (59%) cases of schwannomas and 17 (41%) cases of meningiomas, with a prevalent location in the thoracic spine. The average schwannomas volume was 3,6 ±2,7 cm 3 , whereas the average meningiomas volume was 1.1 ±0.5 cm 3 . Total excision was achieved in all cases. Operative time of schwannomas was longer (p=0.001) respect to meningiomas with higher intra-operative blood loss (p=0.000). Total laminectomy approach was performed in 24 out of 41 patients (59%) and unilateral hemilaminectomy approach in 17 out of 41 (41%) patients. Unilateral hemilaminectomy was associated with shorter postoperative bed rest (p=0.003), shorter hospitalization (p=0.028) and lower postoperative pain (p=0.02) respect to total laminectomy. Conclusions: Both spinal schwannomas and spinal meningiomas in various size can be safely and effectively treated with unilateral hemilaminectomy approach. This approach grants more advantages compared with standard total laminectomy, including shorter postoperative bed rest, shorter hospitalization and reduced postoperative pain. spinal schwannomas spinal meningiomas laminectomy hemilaminectomy spinal intradural extramedullary tumors Introduction Intradural extramedullary (IDEM) tumors account the 80% of all intraspinal tumors in adults. Schwannomas are the most common IDEM tumors (30% of cases), followed by meningiomas (25% of cases) (1). These tumors are benign lesions and gross total resection is the treatment of choice with an excellent functional outcome and very low recurrence rate (2,3,4,5,6,7). The traditional surgical approach includes total laminectomy extending to levels above and below the tumour (8). This approach provides a wide working area, but it is associated with significant tissue trauma and postoperative pain, instability and/or deformity especially after multilevel laminectomy (9,10). Nowadays thanks to the concept of minimally invasive surgery, there is an increasing interest to reduce the amount of bone and ligament removal in spinal surgery especially for degenerative disease (11,12,13,14). Recently these techniques have been applied successfully in the treatment of spinal intradural tumors (15,16,17,18) but still today the best surgical approach is debated. In this paper, we report the results of a surgical series of patients affected by spinal schwannomas and meningiomas who underwent surgical resection by laminectomy or hemilaminectomy comparing the clinical results between the two approaches. Materials and Methods We retrospectively reviewed our surgical series of consecutive patients with IDEM tumors who underwent surgical resection via total laminectomy or via unilateral hemilaminectomy in our Institute between January 2013 and January 2023. The diagnosis was obtained by contrast-enhanced magnetic resonance imaging (MR) and it was confirmed by histopathological examination. Baseline medical data were collected. Clinical symptoms were reviewed using patients’ medical charts. Preoperative and postoperative neurological status were assessed by the American Spinal Injury Association (ASIA) Impairment Scale (19). All patients underwent spinal MR preoperatively and during follow up. Tumor size was measured on contrast-enhanced T1-weighted MR imaging using the widest diameter in three planes and tumor volume was calculated (ellipsoid methods volume= D1xD2xD3/2). Operative and perioperative details recorded included the extent of resection, operative time, amount of blood loss, need for transfusion, length of postoperative bed rest and hospitalization. We also collected 1-month postoperative back pain through Numeric Pain Rating Scale (NRS score) (20). Additionally, postoperative complications were recorded. All methods and procedures were carried out in accordance with current clinical guidelines and regulations. The study was conducted in accordance with the Declaration of Helsinki and Ethical approval was waived by our local ethics committee in view of the retrospective nature of the study and all the procedures being performed were part of the routine care. Informed consent was obtained before each surgical procedure from all subjects or their legal guardians. Statistical analysis: Values are presented as mean ± standard deviation (SD) for continuous variables and as numbers and percentages for categorical variables. Student’s t test, Chi-squared test, Mann-Whitney test and binary logistic regression analysis were used, as appropriate. Results were considered statistically significant for p value ≤0.05. Statistical analysis was performed by the software package SPSS, version 25.0 (Chicago, IL, USA). Results We included 41 consecutive patients affected by spinal schwannoma and meningioma who underwent surgical resection with a follow up of maximum 10 years and minimum 1 year. Our study population consisted of 17 males and 24 females with a mean age of 62.5±14.6 years (range from 33 to 87 years) ( Table 1 ). The clinical onset and the type of the tumors are reported in Table 1 . In our surgical series of schwannomas, the average volume of schwannomas was 3,6 ±2,7 cm 3 , whereas the average volume of meningiomas was 1.1 ±0.5 cm 3 . We achieved the total excision in all patients. Compared with preoperative neurological dysfunction, after surgery there was a significant improvement in the neurological status ( Table 1 ). The total laminectomy was performed in 24 out of 41 patients (59%) while unilateral hemilaminectomy was performed in 17 out of 41 patients (41%) ( Table 1 ); hemilaminectomy was performed in 13 patients out of 24 affected by schwannoma and 4 patients out of 17 affected by meningiomas ( Table 2 ). In our surgical series, postoperative complications were observed in 9 (21.9%) patients out of 41 and included CSF leakage in 4 cases (9.7%) with the need of spinal drainage for 1 week, wound infection in 4 cases (9.7%) with healing after antibiotic therapy. We also reported epidural hematoma in one patients that required re-operation. No deaths were recorded in the series. The operative time was longer for resection of schwannomas than for resection of meningiomas (209.6±79.0 vs 132.4±46.6 minutes, respectively; p=0.001), as well as the intraoperative blood loss was higher in the schwannoma group (1.6 vs 1.5 g/dl, respectively; p=0.000). We noticed no differences between the two groups of tumors regard to postoperative complications, hospital stay and postoperative length bed rest ( Table 2 ). In our surgical series, compared to total laminectomy, unilateral hemilaminectomy was associated with shorter length bed rest (77.8±33.3 vs 46.5±27.3 hours, respectively; p=0.003) and so with shorter hospital stay (11.9±4.8 vs 8.9±2.9 days, respectively; p=0.028). At 1month-follow up, the means NRS score was 4.29±1.9 in the group of laminectomy and 2.8±1.8 in the group of unilateral hemilaminectomy (p=0.02). Operative time was comparable between the total laminectomy and the unilateral hemilaminectomy groups (170.7±70.0 vs 187.3±87.4 minutes, respectively; p=0.503). We found no differences between the two approaches groups in the intraoperative blood loss and incidence of postoperative complications ( Table 3 ). Discussion Surgery is the first choice treatment for spinal schwannoma and meningioma. The surgical goals are gross total tumor resection and the maintenance or restore neurological functions. Laminectomy offers a large exposure of the dorsal surface of the spinal cord and nerve roots with wide working area. However, total laminectomy is associated with tissue trauma and high intraoperative blood loss, prolonged postoperative bed rest and hospitalization (16,21,22,23). According to the “three column” concept of the spine proposed by Denis in 1983 (24), the preservation of the integrity of the posterior column muscles and ligaments is of great importance for the spinal stability and the sagittal balance (23). The rationale for unilateral hemilaminectomy, which is less invasive, is to preserve the supraspinous and interspinous ligaments, the paravertebral muscle of one side and posterior bony elements as much as possible (25). For this reason, unilateral hemilaminectomy has more benefits with regard to postoperative spinal stability comparing with total laminectomy (18,26,27). Nowadays hemilaminectomy is widely used in spinal degenerative diseases but Yasargil et al, with their experience in microneurosurgery, recommended hemilaminectomy for nearly any type of intradural tumors (29). Literature documents that this technique is associated with reduced postoperative pain, low intraoperative blood loss, earlier mobilization and shorter hospital stays (17,25,26,28). Furthermore several studies (15,16,17,18,26,27,28) reported that hemilaminectomy could be applied to spinal tumors without significant adverse effects and that it was even considered superior to the laminectomy in intradural extramedullary tumors. Some Authors have demonstrated that hemilaminectomy could also performed for the resection of partial intramedullary tumors with favourable results (29,30,31). Sun et al described a potential application of the hemilaminectomy in all lateral intradural lesions, whether located ventrally or laterally (32). In our retrospective analysis, 24 spinal schwannomas with average tumor volume of 3,6 ±2,7 cm 3 and 4 meningiomas with average tumor volume of 1,1 ±0,5 cm 3 were totally resected by unilateral hemilaminectomy with favourable outcomes. Compared to total laminectomy, we documented that unilateral hemilaminectomy had shorter hospital stays, reduced length of postoperative bed rest and less postoperative pain with statistically significance. Our results, in line with the results of previous studies (16,17,18,25,26,27,28,31,32,33,34), demonstrated that this approach is useful and safe also for the resection of large spinal meningioma and schwannoma. In our series schwannomas had wider volume than meningiomas. This was due to the location of all meningiomas in the dorsal region where the diameter of the spinal canal is narrow respect to the lumbar spine. For this reason, meningiomas were diagnosed early respect to schwannomas, that was localized more frequently in the lumbar spine in a wide spinal canal. One possible disadvantage of unilateral hemilaminectomy for large tumors is the narrow surgical corridor formed by the spinous processes and ipsilateral facet joint with risks of dural and nerve root damage or incomplete tumor removal. However, in our experience and in accordance with some Authors (16,18,26,27,28,29,33,34), partial facetectomy, undercutt of the spinous process base, oblique tilting of the operating table and ipsilateral dural flap fixed to the muscle or fascia near the facet joint allow to visualize controlateral side of the spinal cord and to remove completely the tumor. With this approach we create a wide working corridor for the total excision of the tumor, even large ones, with the assistence of the microscope. Recently, Alvarez-Crespo et al reported that the average operative time for resection of spinal schwannomas was 293 minutes with the average intraoperative blood loss of 451.88 ml (35). In our surgical series, the operative time was 209.6±79 minutes with less intraoperative blood loss of 160 ml. In this study we found that unilateral hemilaminectomy approach had at least equivalent or longer operative time compared to total laminectomy but may depends on neurosurgeons’ skill. Therefore, we suggest that unilateral hemilaminectomy should be used as a suitable option in spinal meningiomas and schwannomas removal, since one of the major benefit of this approach is the control of intraoperative blood loss that in case of schwannomas is mandatory. The limitations of this study is the retrospective analysis and the small number of patients with the need of further studies. Conclusion Our study documents that unilateral hemilaminectomy approach for the resection of spinal schwannoma and meningioma offers several advantages compared to standard total laminectomy, including shorter postoperative bed rest, shorter hospital stays and less postoperative pain, allowing adequate vision of the surgical area and control of intra-operative bleeding. It is mandatory that neurosurgeon have adequate experience with unilateral hemilaminectomy approach in order to totally remove these tumoral lesions without injury of the spinal cord and nerve roots. More extensive randomized and prospective trials are necessary to elucidate the role of unilateral hemilaminectomy in the surgical management of spinal tumors. Declarations Data Statement : The datasets used and analysed during the current study available from the corresponding author on reasonable request. References Abul-Kasim K, Thurnher MM, McKeever P, Sundgren PC. Intradural spinal tumors: current classification and MRI features. Neuroradiology 2008; 50:301-314 Ottenhausen M, Ntoulias G, Bodhinayake I, Ruppert FH, Schreiber S, Förschler A, Boockvar JA, Jödicke A. Intradural spinal tumors in adults-update on management and outcome. Neurosurgical Review 2019; 42 (2): 371-388 Tonn JC, Grossman SA, Rutka JT, Westphal M. Neuro-oncology of CNS tumors. Springer, Berlin Heidelberg City 2006 Setzer M, Vatter H, Marquardt G, Seifert V, Vrionis FD. Management of spinal meningiomas: surgical results and a review of the literature. Neurosurg Focus 2007; 23:E14 Gottfried ON, Gluf W, Quinones-Hinojosa A, Kan P, Schmidt MH. Spinal meningiomas: surgical management and outcome. Neurosurg Focus 2003; 14:32 Lenzi J, Anichini G, Landi A et al. 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J Neurol Surg A Cent Eur Neurosurg 2021; 82:552-555 Alvarez-Crespo DJ, Conlon M, Faraz Kazim S, Skandalakis GP, Bowers CA, Chhabra K, Tarawneh O, Arbuiso S, Cole KL, Dominguez J, Dicpinigaitis AJ, Vellek J, Thommen R, Bisson EF, Couldwell WT, Cole CD, Schmidt MH. Clinical characteristics and surgical outcomes of 2542 patients with spinal schwannomas: a systematic review and meta-analysis. Word Neurosurg 2023; 23:S1878-8750 Tables Table 1 General characteristics of patients Characteristics Patients (n=41) Sex male (n,%) female (n,%) 17 (41) 24 (59) Age (years, mean±DS°) 62.5±14.6 Clinical signs pain (n,%) sensory deficit (n,%) motor deficit (n,%) bowel/urinary dysfunction (n,%) 22 (53.6) 18 (44.0) 11 (26.8) 3 (7.3) Preoperative ASIA score * A (n,%) B (n,%) C (n,%) D (n,%) E (n,%) - 1 (2.4) 12 (29.3) 26 (63.4) 2 (49) Postoperative ASIA score * A (n,%) B (n,%) C (n,%) D (n,%) E (n,%) - - 1 (2.4) 17 (41.5) 23 (56.1) Type of Tumor schwannoma (n,%) meningioma (n,%) 24 (59) 17 (41) Surgery Total laminectomy (n,%) Unilateral hemilaminectomy (n,%) 24 (59) 17 (41) °DS: standard deviation *ASIA score: American Spinal Injury Association Impairment Scale Table 2 Characteristics of patients according to pathology Characteristics Meningiomas (n=17) Schwannomas (n=24) P value* Tumor volume (cm 3 , mean ±DS°) 1.1±0.5 3.6±2.7 - Type of surgery Total laminectomy (n,%) Unilateral hemilaminectomy (n,%) 13 (54.2) 4 (23.5) 11 (45.8) 13 (76.5) - Site of surgery cervical (n,%) thoracic (n,%) lumbar (n,%) - 17 (100) - 4 (16.7) 11 (45.8) 9 (35.5) - Operative time (minutes, mean ±DS°) 132.4±46.6 209.6±79.0 0.001 Intraoperative blood loss (g/dl) 1.5 1.6 0.000 Bed rest time (hours, mean ±DS°) 59.1±25.4 68.9±39.5 0.372 Hospital stays time (days, mean ±DS°) 9.6±3.8 11.4±4.7 0.20 Postoperative complications wound infection (n,%) CSF leakage (n,%) Epidural bleeding (n,%) 3 (17.6) 2 (11.8) 1 (5.9) 1 (4.1) 2 (8.3) - - °DS: standard deviation * P value significant ≤ 0.05 Table 3 Characteristics of patients according to surgical approach Characteristics Laminectomy (n=24) Hemilaminectomy (n=17) P value* Site of surgery cervical (n,%) thoracic (n,%) lumbar (n,%) 1 (4.2) 20 (83.3) 3 (12.5) 3 (17.6) 8 (47.1) 6 (35.3) - - - Operative time (minutes, mean ±DS°) 170.7±70.0 187.3±87.4 0.503 Intraoperative blood loss (g/dl) 1.6 1.6 0.051 Bed rest time (hours, mean ±DS°) 77.8±33.3 46.5±27.3 0.003 Hospital stays time (days, mean ±DS°) 11.9±4.8 8.9±2.9 0.028 Postoperative complications wound infection (n,%) CSF leakage (n,%) Epidural bleeding (n,%) 2 (8.3) 4 (16.7) 1 (8.3) 2 (11.7) - - 0.725 1-month follow up NRS score § (mean±DS°) 4.29±1.9 2.8±1.8 0.02 °DS: standard deviation * P value significant ≤ 0.05 § NRS score: Numeric Pain Rating Scale Additional Declarations No competing interests reported. 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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-4685546","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":333191503,"identity":"a3b423d3-995a-41d7-bdef-60e19a6c8a58","order_by":0,"name":"Mauro Dobran","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAwklEQVRIiWNgGAWjYDCCAzwQmh9EJBSQokWyAaTFgBQtBgfAJBE6+I73Ht3ws+2enPH51YkfHhgwyPOLHcCvRfLMubSbvW3FxmY33m6WADrMcObsBPxaDG7kmN3gbUtI3Hbj7AaQlgSD20RoufkXqGXzjLObfxCt5TbIlg38vduIswXkl9sy5xKMJW7wbrNIMJAg7BdgiB27+aYsQY6//+zmmz8qbOT5pQloQQAJsEoJYpWDAP8BUlSPglEwCkbBSAIAZJdKk2NnPIwAAAAASUVORK5CYII=","orcid":"","institution":"Marche Polytechnic University","correspondingAuthor":true,"prefix":"","firstName":"Mauro","middleName":"","lastName":"Dobran","suffix":""},{"id":333191505,"identity":"9370784d-2424-45a8-a7c3-a344c5af2512","order_by":1,"name":"Serena Vittoria Lisi","email":"","orcid":"","institution":"Marche Polytechnic University","correspondingAuthor":false,"prefix":"","firstName":"Serena","middleName":"Vittoria","lastName":"Lisi","suffix":""},{"id":333191506,"identity":"915733e3-3eeb-4f4b-9310-814fc0766b53","order_by":2,"name":"Denis Aiudi","email":"","orcid":"","institution":"Marche Polytechnic University","correspondingAuthor":false,"prefix":"","firstName":"Denis","middleName":"","lastName":"Aiudi","suffix":""},{"id":333191508,"identity":"9bf489ad-000e-44c9-813e-28b3a1182a7f","order_by":3,"name":"Fabiola Cappella","email":"","orcid":"","institution":"Marche Polytechnic University","correspondingAuthor":false,"prefix":"","firstName":"Fabiola","middleName":"","lastName":"Cappella","suffix":""},{"id":333191509,"identity":"b0a8f6f9-cf5a-474b-9d10-a4feac3441d9","order_by":4,"name":"Mario Chiapponi","email":"","orcid":"","institution":"Marche Polytechnic University","correspondingAuthor":false,"prefix":"","firstName":"Mario","middleName":"","lastName":"Chiapponi","suffix":""},{"id":333191510,"identity":"394cbb6f-8cbf-47ff-9249-5d84906ff416","order_by":5,"name":"Elena Bianchi","email":"","orcid":"","institution":"Marche Polytechnic University","correspondingAuthor":false,"prefix":"","firstName":"Elena","middleName":"","lastName":"Bianchi","suffix":""},{"id":333191511,"identity":"7c6d07b3-5f10-4d42-8273-7c14ddeb8059","order_by":6,"name":"Alessio Iacoangeli","email":"","orcid":"","institution":"Marche Polytechnic University","correspondingAuthor":false,"prefix":"","firstName":"Alessio","middleName":"","lastName":"Iacoangeli","suffix":""},{"id":333191512,"identity":"0c97ea6a-d8ea-4e8f-8c72-0ed90d8a1b00","order_by":7,"name":"Alessandro Di Rienzo","email":"","orcid":"","institution":"Marche Polytechnic University","correspondingAuthor":false,"prefix":"","firstName":"Alessandro","middleName":"Di","lastName":"Rienzo","suffix":""}],"badges":[],"createdAt":"2024-07-04 09:45:43","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4685546/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4685546/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":67304515,"identity":"e4323f37-c1db-44e6-bb7a-8fa0c4f35cbf","added_by":"auto","created_at":"2024-10-23 13:02:01","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":407367,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4685546/v1/660b682d-53c9-44cd-90df-c4be2630a5d2.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eA Comparison of Laminectomy and Hemilaminectomy Approaches for Resection of Spinal Schwannomas and Meningiomas\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eIntradural extramedullary (IDEM) tumors account the 80% of all intraspinal tumors in adults. Schwannomas are the most common IDEM tumors (30% of cases), followed by meningiomas (25% of cases) (1). These tumors are benign lesions and gross total resection is the treatment of choice with an excellent functional outcome and very low recurrence rate (2,3,4,5,6,7).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe traditional surgical approach includes total laminectomy extending to levels above and below the tumour (8). This approach provides a wide working area, but it is associated with significant tissue trauma and postoperative pain, instability and/or deformity especially after multilevel laminectomy (9,10). \u0026nbsp; Nowadays thanks to the concept of minimally invasive surgery, there is \u0026nbsp;an increasing interest to reduce the amount of bone and ligament removal in spinal surgery especially for degenerative disease (11,12,13,14). Recently these techniques have been applied successfully in the treatment of spinal intradural tumors (15,16,17,18) but still today the best surgical approach is debated.\u003c/p\u003e\n\u003cp\u003eIn this paper, we report the results of a surgical series of patients affected by spinal schwannomas and meningiomas who underwent surgical resection by laminectomy or hemilaminectomy comparing the clinical results between the two approaches.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003eWe retrospectively reviewed our surgical series of \u0026nbsp;consecutive patients with IDEM tumors who underwent surgical resection via total laminectomy or via unilateral hemilaminectomy in our Institute between January 2013 and January 2023. The diagnosis was obtained by contrast-enhanced magnetic resonance imaging (MR) and it was confirmed by histopathological examination.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eBaseline medical data were collected. Clinical symptoms were reviewed using patients\u0026rsquo; medical charts. Preoperative and postoperative neurological status were assessed by the American Spinal Injury Association (ASIA) Impairment Scale (19). All patients underwent spinal MR preoperatively and during follow up. Tumor size was measured on contrast-enhanced T1-weighted MR imaging using the widest diameter in three planes and tumor volume was calculated (ellipsoid methods volume= D1xD2xD3/2). Operative and perioperative details recorded included the extent of resection, operative time, amount of blood loss, need for transfusion, length of postoperative bed rest and hospitalization. We also collected 1-month postoperative back pain through Numeric Pain Rating Scale (NRS score) (20). Additionally, postoperative complications were recorded. All methods and procedures were carried out in accordance with current clinical guidelines and regulations. The study was conducted in accordance with the Declaration of Helsinki and Ethical approval was waived by our local ethics committee in view of the retrospective nature of the study and all the procedures being performed were part of the routine care. \u0026nbsp;Informed consent was obtained before each surgical procedure from all subjects or their legal guardians.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eStatistical analysis:\u003c/strong\u003e Values are presented as mean \u0026plusmn; standard deviation (SD) for continuous variables and as numbers and percentages for categorical variables. Student\u0026rsquo;s t test, Chi-squared test, Mann-Whitney test and binary logistic regression analysis were used, as appropriate. Results were considered statistically significant for p value \u0026le;0.05. Statistical analysis was performed by the software package SPSS, version 25.0 (Chicago, IL, USA).\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eWe included 41 consecutive patients affected by spinal schwannoma and meningioma who underwent surgical resection with a follow up of maximum 10 years and minimum 1 year. Our study population consisted of 17 males and 24 females with a mean age of 62.5\u0026plusmn;14.6 years (range from 33 to 87 years) (\u003cem\u003eTable 1\u003c/em\u003e).\u003c/p\u003e\n\u003cp\u003eThe clinical onset and the type of the tumors are reported in \u003cem\u003eTable 1\u003c/em\u003e. In our surgical series of schwannomas, the average volume of schwannomas was 3,6 \u0026plusmn;2,7 cm\u003csup\u003e3\u003c/sup\u003e, whereas the average volume of meningiomas was 1.1 \u0026plusmn;0.5 cm\u003csup\u003e3\u003c/sup\u003e. We achieved the total excision in all patients. Compared with preoperative neurological dysfunction, after surgery there was a significant improvement in the neurological status (\u003cem\u003eTable 1\u003c/em\u003e).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe total laminectomy was performed in 24 out of 41 patients (59%) while unilateral hemilaminectomy was performed in 17 out of 41 patients (41%) (\u003cem\u003eTable 1\u003c/em\u003e); hemilaminectomy was performed in 13 patients out of 24 affected by schwannoma and 4 patients out of 17 affected by meningiomas (\u003cem\u003eTable 2\u003c/em\u003e). In our surgical series, postoperative complications were observed in 9 (21.9%) patients out of 41 and included CSF leakage in 4 cases (9.7%) with the need of spinal drainage for 1 week, wound infection in 4 cases (9.7%) with healing after antibiotic therapy. We also reported epidural hematoma in one patients that required re-operation. No deaths were recorded in the series.\u003c/p\u003e\n\u003cp\u003eThe operative time was longer for resection of schwannomas than for resection of meningiomas (209.6\u0026plusmn;79.0 \u003cem\u003evs\u003c/em\u003e 132.4\u0026plusmn;46.6 minutes, respectively; p=0.001), as well as the intraoperative blood loss was higher in the schwannoma group (1.6 \u003cem\u003evs\u003c/em\u003e 1.5 g/dl, respectively; p=0.000). We noticed no differences between the two groups of tumors regard to postoperative complications, hospital stay and postoperative length bed rest (\u003cem\u003eTable 2\u003c/em\u003e). In our surgical series, compared to total laminectomy, unilateral hemilaminectomy was associated with shorter length bed rest (77.8\u0026plusmn;33.3 \u003cem\u003evs\u003c/em\u003e 46.5\u0026plusmn;27.3 hours, respectively; p=0.003) and so with shorter hospital stay (11.9\u0026plusmn;4.8 \u003cem\u003evs\u003c/em\u003e 8.9\u0026plusmn;2.9 days, respectively; p=0.028). At 1month-follow up, the means NRS score was 4.29\u0026plusmn;1.9 in the group of laminectomy and 2.8\u0026plusmn;1.8 in the group of unilateral hemilaminectomy (p=0.02). Operative time was comparable between the total laminectomy and the unilateral hemilaminectomy groups (170.7\u0026plusmn;70.0 \u003cem\u003evs\u003c/em\u003e 187.3\u0026plusmn;87.4 minutes, respectively; p=0.503).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWe found no differences between the two approaches groups in the intraoperative blood loss and incidence of postoperative complications (\u003cem\u003eTable 3\u003c/em\u003e).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eSurgery is the first choice treatment for spinal schwannoma and meningioma. The surgical goals are gross total tumor resection and the maintenance or restore neurological functions. Laminectomy offers a large exposure of the dorsal surface of the spinal cord and nerve roots with wide working area. However, total laminectomy is associated with tissue trauma and high intraoperative blood loss, prolonged postoperative bed rest and hospitalization (16,21,22,23). According to the \u0026ldquo;three column\u0026rdquo; concept of the spine proposed by Denis in 1983 (24), the preservation of the integrity of the posterior column muscles and ligaments is of great importance for \u0026nbsp;the spinal stability and the sagittal balance (23). The rationale for unilateral hemilaminectomy, which is less invasive, is to preserve the supraspinous and interspinous ligaments, the paravertebral muscle of one side and posterior bony elements as much as possible (25). For this reason, unilateral hemilaminectomy has more benefits with regard to postoperative spinal stability comparing with total laminectomy (18,26,27). Nowadays hemilaminectomy is widely used in spinal degenerative diseases but Yasargil et al, with their experience in microneurosurgery, recommended hemilaminectomy for nearly any type of intradural tumors (29). Literature documents that this technique is associated with reduced postoperative pain, low intraoperative blood loss, earlier mobilization and shorter hospital stays (17,25,26,28). Furthermore several studies (15,16,17,18,26,27,28) reported that hemilaminectomy could be applied to spinal tumors without significant adverse effects and that it was even considered superior to the laminectomy in intradural extramedullary tumors. Some Authors have demonstrated that hemilaminectomy could also performed for the resection of partial intramedullary tumors with favourable results (29,30,31). Sun et al described a potential application of the hemilaminectomy in all lateral intradural lesions, whether located ventrally or laterally (32).\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;In our retrospective analysis, 24 spinal schwannomas with average tumor volume of 3,6 \u0026plusmn;2,7 cm\u003csup\u003e3\u003c/sup\u003e and 4 meningiomas with average tumor volume of 1,1 \u0026plusmn;0,5 cm\u003csup\u003e3\u003c/sup\u003e were totally resected by unilateral hemilaminectomy with favourable outcomes. Compared to total laminectomy, we documented that unilateral hemilaminectomy had shorter hospital stays, reduced length of postoperative bed rest and less postoperative pain with statistically significance. Our results, in line with the results of previous studies (16,17,18,25,26,27,28,31,32,33,34), demonstrated that this approach is useful and safe also for the resection of large spinal meningioma and schwannoma. In our series schwannomas had wider volume than meningiomas. This was due to the location of all meningiomas in the dorsal region where the diameter of the spinal canal is narrow respect to the lumbar spine. For this reason, meningiomas were diagnosed early respect to schwannomas, that was localized more frequently in the lumbar spine in a wide spinal canal. One possible disadvantage of unilateral hemilaminectomy for large tumors is the narrow surgical corridor formed by the spinous processes and ipsilateral facet joint with risks of dural and nerve root damage or incomplete tumor removal. However, in our experience and in accordance with some Authors (16,18,26,27,28,29,33,34), partial facetectomy, undercutt of the spinous process base, oblique tilting of the operating table and ipsilateral dural flap fixed to the muscle or fascia near the facet joint allow to visualize controlateral side of the spinal cord and to remove completely the tumor.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWith this approach we create a wide working corridor for the total excision of the tumor, even large ones, with the assistence of the microscope.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eRecently, Alvarez-Crespo et al reported that the average operative time for resection of spinal schwannomas was 293 minutes with the average intraoperative blood loss of 451.88 ml (35). In our surgical series, the operative time was 209.6\u0026plusmn;79 minutes with less intraoperative blood loss of 160 ml.\u003c/p\u003e\n\u003cp\u003eIn this study we found that unilateral hemilaminectomy approach had at least equivalent or longer operative time compared to total laminectomy but may depends on neurosurgeons\u0026rsquo; skill. Therefore, we suggest that unilateral hemilaminectomy should be used as a suitable option in spinal meningiomas and schwannomas removal, since one of the major benefit of this approach is the control of intraoperative blood loss that in case of schwannomas is mandatory.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe limitations of this study is the retrospective analysis and the small number of patients with the need of further studies.\u0026nbsp;\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eOur study documents that unilateral hemilaminectomy approach for the resection of spinal schwannoma and meningioma offers several advantages compared to standard total laminectomy, including shorter postoperative bed rest, shorter hospital stays and less postoperative pain, allowing adequate vision of the surgical area and control of intra-operative bleeding. It is mandatory that neurosurgeon have adequate experience with unilateral hemilaminectomy approach in order to totally remove these tumoral lesions without injury of the spinal cord and nerve roots. More extensive randomized and prospective trials are necessary to elucidate the role of unilateral hemilaminectomy in the surgical management of spinal tumors.\u003c/p\u003e\n"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eData Statement\u003c/strong\u003e: The datasets used and analysed during the current study available from the corresponding author on reasonable request.\u003c/p\u003e\n"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAbul-Kasim K, Thurnher MM, McKeever P, Sundgren PC. Intradural spinal tumors: current classification and MRI features. Neuroradiology 2008; 50:301-314\u003c/li\u003e\n\u003cli\u003eOttenhausen M, Ntoulias G, Bodhinayake I, Ruppert FH, Schreiber S, F\u0026ouml;rschler A, Boockvar JA, J\u0026ouml;dicke A. 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The optimal surgical approach to intradural spinal tumors: laminectomy or hemilaminectomy? Cureus 2020; 12:e7084\u003c/li\u003e\n\u003cli\u003eYeo DK, Im SB, Park KW, Shin DS, Kim BT, Shin WH. Profiles of spinal cord tumors removed through a unilateral hemilaminectomy. J Korean Neurosurg Soc. 2011; 50: 195-200\u003c/li\u003e\n\u003cli\u003ePompili A, Caroli F, Crispo F, Giovannetti M, Raus I, Vidiri A et al. Unilateral laminectomy approach for the removal of spinal meningiomas and schwannomas: impact on pain, spinal stability and neurologic results. World Neurosurg 2016; 85:282-91\u003c/li\u003e\n\u003cli\u003eLei D, Zhou Y, Yao D, Zhang F, Wang X, Jiang X et al. Efficacy of unilateral hemilaminectomy for intraspinal tumor resection: a systematic review and meta-analysis. Ann Palliat Med 2021; 10:984-99\u003c/li\u003e\n\u003cli\u003eRoberts TT, Leonard GR, Cepela DJ. Classifications in brief: American Spinal Injury Association (ASIA) Impairment Scale. 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The three column spine and its significance in the classification of acute thoracolumbar spinal injuries. Spine 1983; 8:817-831\u003c/li\u003e\n\u003cli\u003eKoch Wiewrodt D, Wagner W, Perneczky A. Unilateral multilevel interlaminar fenestration instead of laminectomy or hemilaminectomy: an alternative surgical approach to instraspinal space occupying lesions. J Neurosurg Spine. 2007;6 (5):485-492\u003c/li\u003e\n\u003cli\u003eMannion RJ, Nowitzke AM, Efendy J, Wood MJ. Safety and efficacy of intradural extramedullary spinal tumor removal using a minimally invasive approach. Neurosurgery 2011; 68:208-216\u003c/li\u003e\n\u003cli\u003eTurel MK, D\u0026rsquo;Souza WP, Rajshekhar V. Hemilaminectomy approach for intradural extramedullary spinal tumors: an analysis of 164 patients. Neurosurg Focus 2015;39:E9\u003c/li\u003e\n\u003cli\u003eSim JE, Noh SJ, Song YJ, Kim HD. Removal of intradural extramedullary spinal cord tumors with unilateral limited laminectomy. J Korean Neurosurg Soc 2008; 43:232-236\u003c/li\u003e\n\u003cli\u003eYasargil MG, Tranmer BI, Adamson TE, Roth P. Unilateral partial hemi-laminectomy for the removal of extra- and intramedullary tumors and AVMs. Adv Tech Stand Neurosurg 1991; 18:113-132\u003c/li\u003e\n\u003cli\u003eChiou SM, Eggert HR, Laborde G, Seeger W. Microsurgical unilateral approaches for spinal tumor surgery: eight years\u0026rsquo; experience in 256 primary operated patients. ACta Neurochir 1989; 100:127-133\u003c/li\u003e\n\u003cli\u003eBalak N. Unilateral partial hemilaminectomy in the removal of a large spinal ependymoma. Spine J 2008; 8:1030-1036\u003c/li\u003e\n\u003cli\u003eSun CX, Meng XL, Xie SN, Yu Y, Yang HJ, Wu B. Unilateral hemilaminectomy for patients with intradural extramedullary tumors. J Zhejiang Univ Sci B 2011; 12:575-581\u003c/li\u003e\n\u003cli\u003eIacoangeli M, Gladi M, Di Rienzo A et al. Minimally invasive surgery for benign intradural extramedullary spinal meningiomas: experience of a single institution in a cohort of elderly patients and review of the literature. Clin Interv Aging 2012; 7:557-564\u003c/li\u003e\n\u003cli\u003eDobran M, Paracino R, Nasi D, Aiudi D, Capece M, Carrassi E, Lattanzi S, Di Rienzo A, Iacoangeli M. Laminectomy versus unilateral hemilaminectomy for the removal of intraspinal schwannoma: experience of a single institution and review of literature. J Neurol Surg A Cent Eur Neurosurg 2021; 82:552-555\u003c/li\u003e\n\u003cli\u003eAlvarez-Crespo DJ, Conlon M, Faraz Kazim S, Skandalakis GP, Bowers CA, Chhabra K, Tarawneh O, Arbuiso S, Cole KL, Dominguez J, Dicpinigaitis AJ, Vellek J, Thommen R, Bisson EF, Couldwell WT, Cole CD, Schmidt MH. Clinical characteristics and surgical outcomes of 2542 patients with spinal schwannomas: a systematic review and meta-analysis. Word Neurosurg 2023; 23:S1878-8750\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1\u0026nbsp;\u003c/strong\u003eGeneral characteristics of patients\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"49.07251264755481%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCharacteristics\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePatients (n=41)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"49.07251264755481%\" valign=\"top\"\u003e\n \u003cp\u003eSex\u003c/p\u003e\n \u003cp\u003emale (n,%)\u003c/p\u003e\n \u003cp\u003efemale (n,%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e17 (41)\u003c/p\u003e\n \u003cp\u003e24 (59)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"49.07251264755481%\" valign=\"top\"\u003e\n \u003cp\u003eAge (years, mean\u0026plusmn;DS\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\" valign=\"top\"\u003e\n \u003cp\u003e62.5\u0026plusmn;14.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"49.07251264755481%\" valign=\"top\"\u003e\n \u003cp\u003eClinical signs\u003c/p\u003e\n \u003cp\u003epain (n,%)\u003c/p\u003e\n \u003cp\u003esensory deficit (n,%)\u003c/p\u003e\n \u003cp\u003emotor deficit (n,%)\u003c/p\u003e\n \u003cp\u003ebowel/urinary dysfunction (n,%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e22 (53.6)\u003c/p\u003e\n \u003cp\u003e18 (44.0)\u003c/p\u003e\n \u003cp\u003e11 (26.8)\u003c/p\u003e\n \u003cp\u003e3 (7.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"49.07251264755481%\" valign=\"top\"\u003e\n \u003cp\u003ePreoperative \u0026nbsp;ASIA score *\u003c/p\u003e\n \u003cp\u003eA (n,%)\u003c/p\u003e\n \u003cp\u003eB (n,%)\u003c/p\u003e\n \u003cp\u003eC (n,%)\u003c/p\u003e\n \u003cp\u003eD (n,%)\u003c/p\u003e\n \u003cp\u003eE (n,%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003cp\u003e1 (2.4)\u003c/p\u003e\n \u003cp\u003e12 (29.3)\u003c/p\u003e\n \u003cp\u003e26 (63.4)\u003c/p\u003e\n \u003cp\u003e2 (49)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"49.07251264755481%\" valign=\"top\"\u003e\n \u003cp\u003ePostoperative ASIA score *\u003c/p\u003e\n \u003cp\u003eA (n,%)\u003c/p\u003e\n \u003cp\u003eB (n,%)\u003c/p\u003e\n \u003cp\u003eC (n,%)\u003c/p\u003e\n \u003cp\u003eD (n,%)\u003c/p\u003e\n \u003cp\u003eE (n,%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003cp\u003e1 (2.4)\u003c/p\u003e\n \u003cp\u003e17 (41.5)\u003c/p\u003e\n \u003cp\u003e23 (56.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"49.07251264755481%\" valign=\"top\"\u003e\n \u003cp\u003eType of Tumor\u003c/p\u003e\n \u003cp\u003eschwannoma (n,%)\u003c/p\u003e\n \u003cp\u003emeningioma (n,%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e24 (59)\u003c/p\u003e\n \u003cp\u003e17 (41)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"49.07251264755481%\" valign=\"top\"\u003e\n \u003cp\u003eSurgery\u003c/p\u003e\n \u003cp\u003eTotal laminectomy (n,%)\u003c/p\u003e\n \u003cp\u003eUnilateral hemilaminectomy (n,%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e24 (59)\u003c/p\u003e\n \u003cp\u003e17 (41)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25.463743676222595%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026deg;DS: standard deviation\u003c/p\u003e\n\u003cp\u003e*ASIA score: American Spinal Injury Association Impairment Scale\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2\u003c/strong\u003e Characteristics of patients according to pathology\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"45.585585585585584%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCharacteristics\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.936936936936938%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eMeningiomas\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(n=17)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"20.36036036036036%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eSchwannomas\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(n=24)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.117117117117118%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP value*\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"45.585585585585584%\" valign=\"top\"\u003e\n \u003cp\u003eTumor volume (cm\u003csup\u003e3\u003c/sup\u003e, mean \u0026plusmn;DS\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.936936936936938%\" valign=\"top\"\u003e\n \u003cp\u003e1.1\u0026plusmn;0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"20.36036036036036%\" valign=\"top\"\u003e\n \u003cp\u003e3.6\u0026plusmn;2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.117117117117118%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e-\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"45.585585585585584%\" valign=\"top\"\u003e\n \u003cp\u003eType of surgery\u003c/p\u003e\n \u003cp\u003eTotal laminectomy (n,%)\u003c/p\u003e\n \u003cp\u003eUnilateral hemilaminectomy (n,%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.936936936936938%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e13 (54.2)\u003c/p\u003e\n \u003cp\u003e4 (23.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"20.36036036036036%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e11 (45.8)\u003c/p\u003e\n \u003cp\u003e13 (76.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.117117117117118%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"45.585585585585584%\" valign=\"top\"\u003e\n \u003cp\u003eSite of surgery\u0026nbsp;\u003c/p\u003e\n \u003cp\u003ecervical (n,%)\u003c/p\u003e\n \u003cp\u003ethoracic (n,%)\u003c/p\u003e\n \u003cp\u003elumbar (n,%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.936936936936938%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003cp\u003e17 (100)\u003c/p\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"20.36036036036036%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e4 (16.7)\u003c/p\u003e\n \u003cp\u003e11 (45.8)\u003c/p\u003e\n \u003cp\u003e9 (35.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.117117117117118%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"45.585585585585584%\" valign=\"top\"\u003e\n \u003cp\u003eOperative time (minutes, mean \u0026plusmn;DS\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.936936936936938%\" valign=\"top\"\u003e\n \u003cp\u003e132.4\u0026plusmn;46.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"20.36036036036036%\" valign=\"top\"\u003e\n \u003cp\u003e209.6\u0026plusmn;79.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.117117117117118%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.001\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"45.585585585585584%\" valign=\"top\"\u003e\n \u003cp\u003eIntraoperative blood loss (g/dl)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.936936936936938%\" valign=\"top\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"20.36036036036036%\" valign=\"top\"\u003e\n \u003cp\u003e1.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.117117117117118%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.000\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"45.585585585585584%\" valign=\"top\"\u003e\n \u003cp\u003eBed rest time (hours, mean \u0026plusmn;DS\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.936936936936938%\" valign=\"top\"\u003e\n \u003cp\u003e59.1\u0026plusmn;25.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"20.36036036036036%\" valign=\"top\"\u003e\n \u003cp\u003e68.9\u0026plusmn;39.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.117117117117118%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e0.372\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"45.585585585585584%\" valign=\"top\"\u003e\n \u003cp\u003eHospital stays time (days, mean \u0026plusmn;DS\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.936936936936938%\" valign=\"top\"\u003e\n \u003cp\u003e9.6\u0026plusmn;3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"20.36036036036036%\" valign=\"top\"\u003e\n \u003cp\u003e11.4\u0026plusmn;4.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.117117117117118%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e0.20\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"45.585585585585584%\" valign=\"top\"\u003e\n \u003cp\u003ePostoperative complications\u003c/p\u003e\n \u003cp\u003ewound infection (n,%)\u003c/p\u003e\n \u003cp\u003eCSF leakage (n,%)\u003c/p\u003e\n \u003cp\u003eEpidural bleeding (n,%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.936936936936938%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e3 (17.6)\u003c/p\u003e\n \u003cp\u003e2 (11.8)\u003c/p\u003e\n \u003cp\u003e1 (5.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"20.36036036036036%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e1 (4.1)\u003c/p\u003e\n \u003cp\u003e2 (8.3)\u003c/p\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.117117117117118%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026deg;DS: standard deviation\u003c/p\u003e\n\u003cp\u003e*\u003cem\u003eP value significant \u0026le; 0.05\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3\u003c/strong\u003e Characteristics of patients according to surgical approach\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"44.18212478920742%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCharacteristics\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.05564924114671%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eLaminectomy\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(n=24)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.9460370994941%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eHemilaminectomy\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(n=17)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.816188870151771%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP value*\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"44.18212478920742%\" valign=\"top\"\u003e\n \u003cp\u003eSite of surgery\u0026nbsp;\u003c/p\u003e\n \u003cp\u003ecervical (n,%)\u003c/p\u003e\n \u003cp\u003ethoracic (n,%)\u003c/p\u003e\n \u003cp\u003elumbar (n,%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.05564924114671%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e1 (4.2)\u003c/p\u003e\n \u003cp\u003e20 (83.3)\u003c/p\u003e\n \u003cp\u003e3 (12.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.9460370994941%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e3 (17.6)\u003c/p\u003e\n \u003cp\u003e8 (47.1)\u003c/p\u003e\n \u003cp\u003e6 (35.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.816188870151771%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"44.18212478920742%\" valign=\"top\"\u003e\n \u003cp\u003eOperative time (minutes, mean \u0026plusmn;DS\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.05564924114671%\" valign=\"top\"\u003e\n \u003cp\u003e170.7\u0026plusmn;70.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.9460370994941%\" valign=\"top\"\u003e\n \u003cp\u003e187.3\u0026plusmn;87.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.816188870151771%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e0.503\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"44.18212478920742%\" valign=\"top\"\u003e\n \u003cp\u003eIntraoperative blood loss (g/dl)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.05564924114671%\" valign=\"top\"\u003e\n \u003cp\u003e1.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.9460370994941%\" valign=\"top\"\u003e\n \u003cp\u003e1.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.816188870151771%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e0.051\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"44.18212478920742%\" valign=\"top\"\u003e\n \u003cp\u003eBed rest time (hours, mean \u0026plusmn;DS\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.05564924114671%\" valign=\"top\"\u003e\n \u003cp\u003e77.8\u0026plusmn;33.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.9460370994941%\" valign=\"top\"\u003e\n \u003cp\u003e46.5\u0026plusmn;27.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.816188870151771%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.003\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"44.18212478920742%\" valign=\"top\"\u003e\n \u003cp\u003eHospital stays time (days, mean \u0026plusmn;DS\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.05564924114671%\" valign=\"top\"\u003e\n \u003cp\u003e11.9\u0026plusmn;4.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.9460370994941%\" valign=\"top\"\u003e\n \u003cp\u003e8.9\u0026plusmn;2.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.816188870151771%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.028\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"44.18212478920742%\" valign=\"top\"\u003e\n \u003cp\u003ePostoperative complications\u003c/p\u003e\n \u003cp\u003ewound infection (n,%)\u003c/p\u003e\n \u003cp\u003eCSF leakage (n,%)\u003c/p\u003e\n \u003cp\u003eEpidural bleeding (n,%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.05564924114671%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e2 (8.3)\u003c/p\u003e\n \u003cp\u003e4 (16.7)\u003c/p\u003e\n \u003cp\u003e1 (8.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.9460370994941%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e2 (11.7)\u003c/p\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.816188870151771%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e0.725\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"44.18212478920742%\" valign=\"top\"\u003e\n \u003cp\u003e1-month follow up NRS score \u003csup\u003e\u0026sect;\u003c/sup\u003e (mean\u0026plusmn;DS\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.05564924114671%\" valign=\"top\"\u003e\n \u003cp\u003e4.29\u0026plusmn;1.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.9460370994941%\" valign=\"top\"\u003e\n \u003cp\u003e2.8\u0026plusmn;1.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.816188870151771%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e0.02\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026deg;DS: standard deviation\u003c/p\u003e\n\u003cp\u003e*\u003cem\u003eP value significant \u0026le; 0.05\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e\u0026sect;\u003c/sup\u003eNRS score: Numeric Pain Rating Scale\u003c/p\u003e\n"}],"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":"spinal schwannomas, spinal meningiomas, laminectomy, hemilaminectomy, spinal intradural extramedullary tumors","lastPublishedDoi":"10.21203/rs.3.rs-4685546/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4685546/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eSpinal schwannomas and meningiomas are the most common spinal cord benign tumors in adults and total excision is the goal of the treatment. The traditional surgical approach is performed by total laminectomy, but recently unilateral hemilaminectomy has been recognized as a valuable surgical alternative.\u003c/p\u003e\n\u003cp\u003eWe report the clinical results of patients affected by spinal schwannoma and meningioma in whom total laminectomy or unilateral hemilaminectomy were performed.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaterial and Methods: \u003c/strong\u003eA retrospective study of patients who underwent resection of spinal meningioma or schwannoma by laminectomy or unilateral hemilaminectomy approaches in our Institute from January 2013 to January 2023 was made. The baseline data of these patients, operative approach and postoperative outcome were compared.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eThe study was performed on 41 patients with mean age of 62.5 ±14.6 years. Our series included 24 (59%) cases of schwannomas and 17 (41%) cases of meningiomas, with a prevalent location in the thoracic spine. The average schwannomas volume was 3,6 ±2,7 cm\u003csup\u003e3\u003c/sup\u003e, whereas the average meningiomas volume was 1.1 ±0.5 cm\u003csup\u003e3\u003c/sup\u003e. Total excision was achieved in all cases. Operative time of schwannomas was longer (p=0.001) respect to meningiomas with higher intra-operative blood loss (p=0.000). Total laminectomy approach was performed in 24 out of 41 patients (59%) and unilateral hemilaminectomy approach in 17 out of 41 (41%) patients. Unilateral hemilaminectomy was associated with shorter postoperative bed rest (p=0.003), shorter hospitalization (p=0.028) and lower postoperative pain (p=0.02) respect to total laminectomy.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eBoth spinal schwannomas and spinal meningiomas in various size can be safely and effectively treated with unilateral hemilaminectomy approach. This approach grants more advantages compared with standard total laminectomy, including shorter postoperative bed rest, shorter hospitalization and reduced postoperative pain.\u003c/p\u003e","manuscriptTitle":"A Comparison of Laminectomy and Hemilaminectomy Approaches for Resection of Spinal Schwannomas and Meningiomas","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-08-05 08:06:34","doi":"10.21203/rs.3.rs-4685546/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":"5525ef3a-06da-4a87-a343-2e259ed51685","owner":[],"postedDate":"August 5th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-10-23T12:53:52+00:00","versionOfRecord":[],"versionCreatedAt":"2024-08-05 08:06:34","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4685546","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4685546","identity":"rs-4685546","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}