Size-Dependent Strategy for Ultrasound-Guided Fine-Needle Aspiration Biopsy of Thyroid Nodules: A Comparison of In-Plane and Out-of-Plane Techniques

Size-Dependent Strategy for Ultrasound-Guided Fine-Needle Aspiration Biopsy of Thyroid Nodules: A Comparison of In-Plane and Out-of-Plane Techniques | 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 Size-Dependent Strategy for Ultrasound-Guided Fine-Needle Aspiration Biopsy of Thyroid Nodules: A Comparison of In-Plane and Out-of-Plane Techniques Xiubin Tang¹, Chunrong Zhong, Yuzhen Wang, Ming Chen This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7026688/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 Objective To compare the clinical efficacy of ultrasound-guided in-plane versus out-of-plane fine-needle aspiration biopsy techniques for identifying thyroid nodules of different sizes and to explore individualized aspiration strategies on the basis of nodule size. Methods: A total of 492 patients who underwent ultrasound-guided fine-needle aspiration biopsy of thyroid nodules from January 2024 to February 2025 were retrospectively included and divided into an in-plane group (n = 275) and an out-of-plane group (n = 217) according to nodule size (group A: 1.0 cm), and the two groups were compared in terms of the satisfaction rates of the specimens, operation times and complication differences and further stratified to analyze the effects of complex anatomical locations (adjacent vessels/trachea). Results The advantage of the in-plane method was significant for ≤ 1.0 cm nodules, with overall specimen satisfaction rates of 98.2% and 98.1% in Groups A and B, respectively, which were significantly greater than those of the out-of-plane method (65.5% and 81.2%, respectively), with a significantly lower percentage of Bethesda Class I nodules (Group A: 1.8% vs. 34.5%; Group B: 1.9% vs. 18.8%) and a significantly lower complication rate in Group A than in the out-of-plane method for complex-location (neighboring vessel/trachea) nodules. The complication rate was lower in Group A for the in-plane approach than for the out-of-plane approach, and the differences were statistically significant (P 1.0 cm nodules, there was no statistically significant difference in the overall specimen satisfaction rate between the two puncture methods (96.8% and 98.3%, respectively, p = 0.29), but the out-of-plane method had a higher specimen satisfaction rate in complex locations (adjacent vessels/trachea) (97.1% vs. 84.6%, p = 0.038), and the complication rate was lower (15.4% for the in-plane method vs. 0% for the out-of-plane approach, p = 0.02). The mean puncture time was shorter for the in-plane method than for the out-of-plane method for ≤ 1.0 cm nodules (4.10 ± 1.0 min, 5.50 ± 2.3 min, respectively, p 1.0 cm nodes with complex locations (adjacent to the blood vessels/trachea) (4.2 ± 1.1 minutes, 5.8 ± 1.5 minutes, p 1.0 cm nodules allows for flexibility, and the out-of-plane approach is recommended to balance efficiency and safety if adjacent to blood vessels/trachea. thyroid nodule ultrasound-guided fine-needle aspiration biopsy individualized aspiration strategy complication Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Thyroid nodules are indeed very common in clinical practice, with a detection rate of up to 20%~76% on ultrasound screening [ 1 , 2 ], but only approximately 5%~ 15% of these are malignant lesions [ 3 , 4 ]. This disparity in the ratio of benign to malignant nodules (approximately 20:1) [ 5 ] makes early and accurate identification of benign and malignant thyroid nodules a key challenge in optimizing diagnostic and therapeutic decisions. Fine-needle aspiration biopsy (FNAB) is the "gold standard" for the diagnosis of benign and malignant thyroid nodules, with a sensitivity and specificity of up to 60%~94.6% and 87.9%~100%, respectively [ 6 , 7 ]. However, approximately 10%~ 25% of FNAB results result in diagnostic delays due to insufficient samples (Bethesda Class I) [ 8 ], and the rate of sampling failure, especially for small nodules (≤ 1.0 cm), is significantly higher [ 9 ]. In recent years, advances in ultrasound-guided techniques (US-FNAB) have greatly improved the accuracy of puncture, with in-plane and out-of-plane puncture becoming the mainstream techniques. The in-plane method can accurately locate small lesions by displaying the entire path of the needle tip in real time, but the large angle of needle insertion may increase the risk of injury to adjacent blood vessels. The out-of-plane method uses short-axis needle insertion, which is easier and safer to perform, but insufficient visualization of the tip of the needle may lead to sampling bias [ 10 , 11 ]. Although several studies have compared the overall efficacy of the two methods, they remain controversial in terms of operational difficulty, sampling effectiveness, and risk of complications: a single-center randomized trial by Raed Farhat et al. demonstrated a higher rate of specimen satisfaction with the in-plane method (89% vs. 74%, p = 0.03) [ 12 ], whereas Cohn et al. concluded that the difference was not statistically significant in their prospective study (91% vs. 88%, p = 0.21) [ 13 ]. These contradictions may stem from the heterogeneity of the study population, especially the failure to stratify the analysis by nodule size. Although the literature emphasizes the importance of thyroid nodule size as an indicator for FNAB, the optimal choice of puncture technique for different nodule sizes has not yet been determined[ 14 ]. In addition, most of the literature focuses on improving the puncture needle type (fine/coarse needle) or risk stratification systems (e.g., ACR-TIRADS), and studies on individualized puncture strategies based on nodule size are lacking [ 15 – 17 ]. This study aims to fill this gap by proposing the first size-dependent stepped puncture strategy through a large-sample retrospective analysis (n = 492): quantitatively comparing specimen satisfaction, operational efficiency, and safety of in-plane versus out-of-plane method FNAB in ≤ 0.5 cm, 0.5 ~ 1.0 cm, and > 1.0 cm thyroid nodules; exploring predictive factors of Bethesda Class I outcomes that reduce the need for repeat punctures; and establishing a framework for clinical decision-making in conjunction with anatomical features (e.g., adjacent vessels/trachea). The results of this study may provide clinicians with an evidence-based basis to promote the precision and standardization of the FNAB technique for thyroid nodules. Materials and methods 1. Research subjects This study used a retrospective cohort study design and included 492 patients who underwent ultrasound-guided fine-needle aspiration biopsy (FNAB) of thyroid nodules between January 2024 and February 2025 at our hospital. The inclusion criteria were based on the 2023 American Thyroid Association (ATA) guidelines [ 5 ]: ① thyroid nodules detected by ultrasound; ② nodules with a maximum diameter of ≥ 0.3 cm; and ③ completion of fine-needle aspiration biopsy with definitive pathologic results. The exclusion criteria were as follows: ① patients with coagulation disorders (INR > 1.5 or platelets < 50×10^9/L); ② patients with severe cardiorespiratory insufficiency (NYHA cardiac function class III-IV); and ③ patients who could not cooperate with the examination. This study was approved by the Ethics Committee of medical ethics committee of zhangzhou hospital, fujian province (Ethics Approval Number: Zhang Medical Lun 2025LWB215). 2. Cluster approach In accordance with the European Thyroid Association of 2022 (EU-TIRADS) criteria [ 6 ], the nodules were categorized into group A ( 1.0 cm) according to their size, and the cases in the in-plane (n = 275) and out-of-plane (n = 217) groups were extracted on the basis of historical data. 3. Instruments and methods A Mindray Resona 8 color Doppler diagnostic ultrasound machine with a probe frequency of 8 ~ 12 MHz was used. Three equally qualified physicians performed ultrasound-guided fine-needle aspiration of the thyroid nodules. Patients were placed in the supine position, and the puncture sites were routinely sterilized. In the out-of-plane group, puncture was performed via the short-axis method, with the needle inserted approximately 5 mm parallel to the midpoint of the long axis of the probe, the ultrasound-guided tip of the needle was introduced into the nodule, and the thyroid nodule was aspirated via a 2 ml vacuum pressure load three times, with 10 rapid and small insertions each time (Fig. 1 ). All three needle entry sites were different, and all were independent punctures. In the in-plane group, puncture was performed via the long-axis method, the needle was inserted approximately 5 mm beside the midpoint of the short axis of the probe, the ultrasound guided the needle tip into the nodule, and the thyroid nodule was aspirated via a vacuum pressure load of 2 ml, three times in total, with 10 rapid and small insertions each time, and the three needle insertion sites were all different (Fig. 2 ). The arrow shows that the tip of the needle is located within the nodule but is not as clearly displayed as the in-plane method of puncturing the needle. The arrow shows that the tip of the needle is located in the nodule, and the puncture needle is clearly visible. 4. Observation indicators The contents were smeared, fixed in 95% ethanol and stained with pasteurization. A single-blind method was used, i.e., the pathologist was unaware of the specimen taken from the plane of the puncture, and a senior pathologist was designated to refer to the Bethesda Reporting System for Thyroid Cytopathology, which is commonly used internationally, for a total of six categories [ 7 ]: I specimens that are undiagnostic or unsatisfactory; lI benign; III cellular atypical lesions of unknown significance; IV follicular or suspicious follicular neoplasms; and V suspected malignant neoplasms; and Vl malignant tumors. The main observations included the following: the specimen pass rate (at least 6 groups of benign or malignant cell populations) (Fig. 3 ) and the time of the puncture operation: from the beginning of the puncture to obtaining a satisfactory specimen. 5. Statistical methods SPSS 26.0 statistical software was used to analyze the data. Measurement data conforming to a normal distribution are expressed as the mean ± standard deviation, and a t test was used; count data are expressed as the frequency (n) or percentage (%), and a chi-square test was used (if the chi-square test requirements were not met, Fisher's exact probability method or successive correction method was used), and the data at the time of puncture were confirmed to conform to a normal distribution by the Shapiro‒Wilk test and t test. The t test was used for normally distributed data, and the median ( M ) was used to describe nonnormally distributed data. Comparisons between two groups were made via the Mann‒Whitney test, and differences were considered statistically significant at P < 0.05. Results 1. Analysis of baseline information The baseline data of patients in each group (Group A: nodules 1.0 cm) were not significantly different between the two puncture methods (all p > 0.05), indicating well-balanced groupings (Table 1 ). Table 1 Comparison of the baseline data of patients enrolled via the intraplanar and extraplanar puncture methods Baseline data Group A ( 1.0 cm) In-plane (n = 111) Outside the plane (n = 29) Statistical/P value In-plane (n = 106) Outside the plane (n = 54) Statistical/p value In-plane (n = 58) Outside the plane (n = 134) Statistical/p value Age/years x ± s 51.7 ± 11.8 49.6 ± 9.7 0.895/0.372 63.5 ± 3.5 50.9 ± 13.4 0.88/0.38 52.7 ± 11.9 48.0 ± 14.17 1.82/0.7 Sex 1.11/0.292 2.63/0.11 0.27/0.6 The male sex 20 7 30 9 15 30 Femininity 91 22 76 45 43 104 Nodule size/x ± s 0.34 ± 0.08 0.36 ± 0.08 -1.27/0.21 0.69 ± 0.14 0.71 ± 0.16 -0.66/0.51 2.11 ± 1.0 2.36 ± 1.1 -1.37/0.17 Position 4.03/0.258 0.386/3.04 0.123/5.77 Falling-rising Tone 24 8 48 23 11 39 Centre 62 18 10 10 27 45 Down 20 1 36 17 12 39 Isthmus 5 2 12 4 8 11 Border 0.941/0.396 0.741/1.15 0.166/5.08 Fitting 64 17 49 29 36 102 Irregular 35 8 45 18 15 20 Vague 7 2 5 3 5 6 Extrathoracic invasion 5 2 7 4 2 6 Calcification 0.906/0.016 0.969/0.548 0.665/2.39 Microcalcification 11 3 27 10 11 14 Comet tail Phenomenon 5 1 11 4 2 9 A point-like strong echo with an unclear meaning 5 1 9 3 3 5 Slight calcification 10 2 24 8 7 12 Peripheral calcification 17 5 10 2 3 7 Structure 0.803/0.063 0.94/0.124 0.5712.01 Substance 106 28 75 39 44 89 Its about substance 5 1 23 11 11 37 Cystic predominance 0 0 5 2 2 4 Spina bifida cystica 0 0 0 0 0 0 Spongy 0 0 3 2 1 4 Blood flow grading 0.14/3.927 0.277/2.56 0.870.71 Level 0 27 12 44 28 5 16 Level 1 73 16 57 24 32 67 Level 2 11 1 5 1 17 40 Level 3 0 0 0 0 4 11 2. Comparison of specimen satisfaction and cytologic diagnostic results of fine-needle aspiration biopsy between the two puncture methods The satisfaction rate of specimen retrieval via the in-plane puncture method was significantly greater than that via the out-of-plane puncture method in Group A (98.2% and 65.5%, respectively) and Group B (98.1% and 81.2%, respectively) (both p < 0.001). However, in Group C, the difference in the specimen satisfaction rate between the two methods was not statistically significant (96.8% and 98.3%, respectively, p = 0.29), which may be related to the fact that larger nodules were easier to localize. In addition, the proportions of Class I in the in-plane method were 1.8% and 1.9% in Groups A and B, respectively, which were significantly lower than those in the out-of-plane method (34.5% and 18.8%), and the difference was statistically significant (p < 0.05) (Table 2 ). Table 2 Comparison of specimen satisfaction rates and cytological diagnosis results of in-plane and out-of-plane puncture FNAB cytological diagnosis results Group A ( 1.0 cm) Satisfactory rate of specimens in the plane (no. of cases/total) Satisfactory rate of specimens outside the plane (number of cases/total number) Satisfactory rate of specimens in the plane (no. of cases/total) Satisfactory rate of specimens outside the plane (number of cases/total number) Satisfactory rate of specimens in the plane (no. of cases/total) Satisfactory rate of specimens outside the plane (number of cases/total number) 98.2%(109/111) 65.5%(19/29) 98.1%(104/106) 81.2%(44/54) 96.6%(56/58) 92.5%(124/134) I class 2 10 2 10 2 10 Ⅱ class 36 4 37 11 28 75 Ⅲ class 23 3 9 6 4 14 Ⅳ class 3 0 1 2 2 3 V class 18 3 23 11 4 5 Ⅵ class 29 9 34 14 18 27 amount to 111 29 106 54 58 134 P price < 0.001* < 0.001 # 0.29** Note: *: Comparison of the satisfaction rates between the in-plane method and out-of-plane methods in Group A; #: Comparison of the satisfaction rates between the in-plane method and out-of-plane methods in Group B; **: Comparison of the satisfaction rates between the in-plane method and out-of-plane methods in Group C. 3. Complex anatomical location subgroup analysis In group A ( 1.0 cm), further sieving of the selection of nodes adjacent to blood vessels/trachea (distance < 2 mm) was performed: for group A (< 0.5 cm), the specimen satisfaction rate of the in-plane method was significantly greater than that of the out-of-plane method (94.4% vs. 50.0%, p = 0.02), and the complication rate was significantly lower than that of the out-of-plane method (p < 0.05), suggesting that, for very small nodes, the in-plane method in a complex location still allows for Group B (0.5 ~ 1.0 cm): the specimen satisfaction rate of the in-plane method remained high (95.7% vs. 66.7%, p = 0.02), further validating the stability of its technique. In Group C (> 1.0 cm), although the difference in the specimen satisfaction rate between the two puncture methods was not statistically significant, the complication rate of the in-plane method was significantly greater than that of the out-of-plane method (Fig. 4 ) (p < 0.05). statistically significant (P < 0.05) (Table 3 ). Table 3 Comparison of puncture effect and complications of complex location nodules in each group Group Metric The plane method The plane-out method P price Group A (< 0.5 cm, n = 18) Specimen satisfaction rate (%) 94.4(17/18) 50.0(2/4) 0.02 Hematoma incidence (%) 5.6(1/18) 25.0(2/4) 0.02 Group B (0.5-1.0 cm, n = 23) Specimen satisfaction rate (%) 95.7(22/23) 66.7(8/12) 0.02 Hematoma incidence (%) 4.3(1/23) 16.7( 4/12) 0.02 Group C (> 1.0 cm, n = 62) Specimen satisfaction rate (%) 84.6(11/13) 97.1(34/35) 0.11 Hematoma incidence (%) 15.4(2/13) 0(0/35) 0.02 4. Comparison of the puncture time between the two puncture methods The mean operating time for the in-plane method for nodules ≤ 1.0 cm was 4.10 ± 1.0 minutes, which was shorter than the 5.50 ± 2.3 minutes for the out-of-plane method (p 1.0 cm was 4.2 ± 1.1 minutes, which was shorter than the 5.8 ± 1.5 minutes for the out-of-plane method (p = 0.003). Discussion The difference in diagnostic efficacy between the modes of operation (in-plane versus out-of-plane) of ultrasound-guided fine-needle aspiration biopsy (FNAB), a core technique for diagnosing the benign and malignant nature of thyroid nodules, has been a focus of research. By comparing the diagnostic efficacy of the two puncture techniques, the results of this study revealed that the in-plane method of FNAB demonstrated significant advantages for identifying thyroid nodules ≤ 1.0 cm in size. Specifically, the performance of the in-plane method FNAB was significantly greater than that of the out-of-plane method in terms of specimen satisfaction and operative time advantage in both Group A (< 0.5 cm) and Group B (0.5 ~ 1.0 cm) (both p < 0.001). By keeping the needle parallel to the long axis of the ultrasound probe, the in-plane technique allows the complete path of the needle from the skin to the target ("proximal-to-distal" approach) to be tracked in real time on the ultrasound image, which is particularly suitable for scenarios requiring precise penetration of multilayered tissues or avoidance of important structures and reduces the need for repeated adjustments of the needle tip position, whereas the out-of-plane method requires repeated adjustments of the angle of the needle during the procedure [ 18 , 19 ]. The results of this study show that the advantage of the in-plane method of FNAB is significant size dependence. For nodules ≤ 1.0 cm, the in-plane method demonstrated a significant advantage over the real-time tip full visualization technique, and even with adjacent vessels/trachea (distance < 2 mm), the in-plane method still had a high rate of specimen satisfaction of 94.4% and 95.7% (both p < 0.05) in complex locations in groups A and B, which was significantly better than that of the out-of-plane method (50.0% and 66.7%). The out-of-plane method had a high hematoma incidence of 25% in complex locations (0% in the in-plane method, p = 0.13), and the nodule size may be a central factor influencing the choice of puncture technique[ 13 ], with very small nodules requiring preference for the in-plane technique to avoid risk. The results of the present study also revealed that the in-plane method significantly reduced the proportion of Bethesda system category I (undiagnostic) nodules ≤ 1.0 cm (group A: 1.8% vs. 34.5%; group B: 1.9% vs. 18.8%, both p < 0.05), thus reducing the risk of repeat puncture due to insufficient samples. This finding not only validates the clinical value of real-time visualization but also agrees with the tip path optimization model proposed by Muzzammil et al. [ 20 ], which suggests that the in-plane method can accurately obtain the cellular components of the nodule by displaying the tip position throughout the entire process and combining it with a cutting-type needle insertion pattern, avoiding interference from the surrounding tissues [ 21 ], whereas the out-of-plane method may lead to a reduction in the number of puncture specimens in the nodule due to the lack of tip visibility. Inadequate visualization of the needle tip may lead to the need for repeated adjustments of the needle direction during small nodule puncture, increasing the risk of local tissue injury. Notably, the out-of-plane approach did not cause any complications in complex nodules > 1.0 cm, which is consistent with the study of Sun et al.[ 22 , 23 ]. that larger nodules provide a wider manipulation space, which further reduces the difficulty of the out-of-plane approach in complex anatomical locations, and that the out-of-plane approach, by using the probe's long-axis paracentesis to enter the needle, can approach the surface of the nodule at a smaller angle to avoid excessive penetration of the needle tip and thus reduce the probability of contact between the needle tip and deep vascular structures. In addition, the out-of-plane approach, which uses the long axis of the probe to access the needle, is able to approach the nodule surface at a smaller angle for nodules close to the trachea, carotid artery, or dorsal thyroid, avoiding excessive penetration of the needle tip and thus reducing the probability of the tip contacting deep vascular structures [ 24 ] and lowering the risk of complications. In addition, this study revealed that the in-plane method has a timeliness advantage for nodules ≤ 1.0 cm and that the out-of-plane method has an advantage for complex location nodules > 1.0 cm. Limitations of this study include the potential bias of its retrospective design and the noninclusion of molecular marker analysis. Future multicenter prospective studies are needed to optimize puncture path planning by combining elastography or artificial intelligence techniques and to explore the role of molecular markers such as BRAF V600E in individualized strategies. Conclusion In summary, a stepped strategy based on nodule size can balance the efficacy and safety of FNAB. Nodules ≤ 1.0 cm in size: Regardless of their location, the in-plane approach is preferred, with significant advantages in terms of its high satisfaction rate and low hematoma risk. >1.0 cm nodule: flexible choice for noncomplicated locations; if adjacent to vessels/trachea, an out-of-plane approach is recommended to balance safety and efficiency. Declarations Acknowledgments We would like to thank the entire Department of Ultrasound for their help and support. Author contributions Design of the work—XT and MC. Article retrieval and data collection—CZ and YW. Article selection—XTand CZ. Data analysis, code writing and mapping—XT and MC. Supervision conducted and responsibility for the entire study—XT. Drafting the manuscript and revising it—all authors. Funding No specific funding for this research. Data availability The datasets used in this study are available from the corresponding author upon request. Ethics approval and consent to participate Approved by the Ethics Committee of Fujian Zhangzhou Hospital: the study uses previously collected and archived clinical data, poses no more than minimal risk, and safeguards participant privacy and rights; thus, informed consent was waived. Consent for publication Not required. Conflict of interest statement The authors declare no competing interests. References Tang JW, Mou JY, Chen J, et al. Discrimination of benign and malignant thyroid nodules through comparative analyses of human saliva samples via metabolomics and deep-learning-guided label-free sers. ACS Appl Mater Interfaces. 2025;17(3):5538-5549. https://doi.org/10.1021/acsami.4 c20503. Ushakov AV. Stages of benign thyroid nodules: principles and ultrasound signs. Quant Imaging Med Surg. 2024;14(8):6108-6122. https://doi.org/10.21037/qims-24-477. Du H, Chen F, Li H, et al. 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Published 2022 Oct 12. https://doi.org/10.3389/fcvm.2022.983532. Evans M, Kang S, Bajaber A, Gordon K, Martin C 3rd. Augmented reality for surgical navigation: a review of advanced needle guidance systems for percutaneous tumor ablation. Radiol Imaging Cancer. 2025 Jan;7(1):e230154. https://doi.org/10.1148/rycan.230154. Haddad RI, Bischoff L, Ball D, et al. Thyroid carcinoma, version 2.2022, NCCN clinical practice guidelines in oncology.J Natl Compr Canc Netw. 2022 Aug. 20(8):925-951. https://doi.org/10.6004/jnccn.2022.0040. 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-7026688","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":492382453,"identity":"594a23fe-74d3-49fb-ac28-0a952ef5faeb","order_by":0,"name":"Xiubin Tang¹","email":"","orcid":"","institution":"Affiliated Zhangzhou Hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Xiubin","middleName":"","lastName":"Tang¹","suffix":""},{"id":492382454,"identity":"941ca50f-c0ce-48b1-9490-892bb3975d83","order_by":1,"name":"Chunrong Zhong","email":"","orcid":"","institution":"Affiliated Zhangzhou Hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Chunrong","middleName":"","lastName":"Zhong","suffix":""},{"id":492382455,"identity":"49cc13ab-31c2-4721-937e-81dd33f0820c","order_by":2,"name":"Yuzhen Wang","email":"","orcid":"","institution":"Affiliated Zhangzhou Hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Yuzhen","middleName":"","lastName":"Wang","suffix":""},{"id":492382456,"identity":"ee80c68e-04b3-4024-b0c1-ed81d9489782","order_by":3,"name":"Ming Chen","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAvklEQVRIiWNgGAWjYBAC9oYDDAwfbNjAHAmitPAcOMDAOCONNC0MDMw8aQykaGE8/HSzTQJftMEB5oO3eRjs8ghrYThmdjsngS13wwG2ZGsehuRiglrsGc6w3c79AdLCYybNw3AgsYGwLUAtFmBb+L+RoIUBrIWHjVgtx8xu9gC1zDzMZmw5xyCZCC0Sh5/d+JFwLLfvePPDG28q7AhrYZA4ACKPAWMHRBsQVA8E/GBTa4hROgpGwSgYBSMVAAABpDyzel7ZQwAAAABJRU5ErkJggg==","orcid":"","institution":"Affiliated Zhangzhou Hospital of Fujian Medical University","correspondingAuthor":true,"prefix":"","firstName":"Ming","middleName":"","lastName":"Chen","suffix":""}],"badges":[],"createdAt":"2025-07-02 07:53:32","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7026688/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7026688/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":88225370,"identity":"0a48f8f8-b134-4fd0-a3ec-c6a66de3b5eb","added_by":"auto","created_at":"2025-08-04 08:37:47","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":252089,"visible":true,"origin":"","legend":"\u003cp\u003eFine needle aspiration biopsy of thyroid nodules via the out-of-plane method\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7026688/v1/9b2a81fed03012fd8740dc12.png"},{"id":88225388,"identity":"3b50cfc2-dffb-481d-91a8-14e574601334","added_by":"auto","created_at":"2025-08-04 08:37:50","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":240191,"visible":true,"origin":"","legend":"\u003cp\u003eFine needle aspiration biopsy of the thyroid nodule via the in-plane method.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7026688/v1/9b4b70ac57f564b1ccc692a1.png"},{"id":88225375,"identity":"12e3e601-cbb6-4391-a08d-27cde8e843e9","added_by":"auto","created_at":"2025-08-04 08:37:47","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":313186,"visible":true,"origin":"","legend":"\u003cp\u003ePathologic findings of papillary thyroid carcinoma (Pap stain × 400)\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7026688/v1/378d1fac7772c42f38538759.png"},{"id":88226800,"identity":"b7dbdd39-c745-4d95-9ce1-c2b720341540","added_by":"auto","created_at":"2025-08-04 08:45:47","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":366490,"visible":true,"origin":"","legend":"\u003cp\u003eUltrasound image of the hematoma after thyroid puncture (the arrow indicates the hematoma)\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7026688/v1/6ef690076cd06d961515b9ce.png"},{"id":104887909,"identity":"814edbc0-5504-4f31-8aff-794fb386d223","added_by":"auto","created_at":"2026-03-18 10:12:56","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2762431,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7026688/v1/6ff81d5b-ad38-40ca-b52e-8997651a9dda.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Size-Dependent Strategy for Ultrasound-Guided Fine-Needle Aspiration Biopsy of Thyroid Nodules: A Comparison of In-Plane and Out-of-Plane Techniques","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThyroid nodules are indeed very common in clinical practice, with a detection rate of up to 20%~76% on ultrasound screening [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], but only approximately 5%~ 15% of these are malignant lesions [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. This disparity in the ratio of benign to malignant nodules (approximately 20:1) [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e] makes early and accurate identification of benign and malignant thyroid nodules a key challenge in optimizing diagnostic and therapeutic decisions. Fine-needle aspiration biopsy (FNAB) is the \"gold standard\" for the diagnosis of benign and malignant thyroid nodules, with a sensitivity and specificity of up to 60%~94.6% and 87.9%~100%, respectively [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. However, approximately 10%~ 25% of FNAB results result in diagnostic delays due to insufficient samples (Bethesda Class I) [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e], and the rate of sampling failure, especially for small nodules (\u0026le;\u0026thinsp;1.0 cm), is significantly higher [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIn recent years, advances in ultrasound-guided techniques (US-FNAB) have greatly improved the accuracy of puncture, with in-plane and out-of-plane puncture becoming the mainstream techniques. The in-plane method can accurately locate small lesions by displaying the entire path of the needle tip in real time, but the large angle of needle insertion may increase the risk of injury to adjacent blood vessels. The out-of-plane method uses short-axis needle insertion, which is easier and safer to perform, but insufficient visualization of the tip of the needle may lead to sampling bias [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Although several studies have compared the overall efficacy of the two methods, they remain controversial in terms of operational difficulty, sampling effectiveness, and risk of complications: a single-center randomized trial by Raed Farhat et al. demonstrated a higher rate of specimen satisfaction with the in-plane method (89% vs. 74%, p\u0026thinsp;=\u0026thinsp;0.03) [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], whereas Cohn et al. concluded that the difference was not statistically significant in their prospective study (91% vs. 88%, p\u0026thinsp;=\u0026thinsp;0.21) [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. These contradictions may stem from the heterogeneity of the study population, especially the failure to stratify the analysis by nodule size.\u003c/p\u003e\u003cp\u003eAlthough the literature emphasizes the importance of thyroid nodule size as an indicator for FNAB, the optimal choice of puncture technique for different nodule sizes has not yet been determined[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. In addition, most of the literature focuses on improving the puncture needle type (fine/coarse needle) or risk stratification systems (e.g., ACR-TIRADS), and studies on individualized puncture strategies based on nodule size are lacking [\u003cspan additionalcitationids=\"CR16\" citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThis study aims to fill this gap by proposing the first size-dependent stepped puncture strategy through a large-sample retrospective analysis (n\u0026thinsp;=\u0026thinsp;492): quantitatively comparing specimen satisfaction, operational efficiency, and safety of in-plane versus out-of-plane method FNAB in \u0026le;\u0026thinsp;0.5 cm, 0.5\u0026thinsp;~\u0026thinsp;1.0 cm, and \u0026gt;\u0026thinsp;1.0 cm thyroid nodules; exploring predictive factors of Bethesda Class I outcomes that reduce the need for repeat punctures; and establishing a framework for clinical decision-making in conjunction with anatomical features (e.g., adjacent vessels/trachea). The results of this study may provide clinicians with an evidence-based basis to promote the precision and standardization of the FNAB technique for thyroid nodules.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003ch3\u003e1. Research subjects\u003c/h3\u003e\n\u003cp\u003e This study used a retrospective cohort study design and included 492 patients who underwent ultrasound-guided fine-needle aspiration biopsy (FNAB) of thyroid nodules between January 2024 and February 2025 at our hospital. The inclusion criteria were based on the 2023 American Thyroid Association (ATA) guidelines [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]: ① thyroid nodules detected by ultrasound; ② nodules with a maximum diameter of \u0026ge;\u0026thinsp;0.3 cm; and ③ completion of fine-needle aspiration biopsy with definitive pathologic results. The exclusion criteria were as follows: ① patients with coagulation disorders (INR\u0026thinsp;\u0026gt;\u0026thinsp;1.5 or platelets\u0026thinsp;\u0026lt;\u0026thinsp;50\u0026times;10^9/L); ② patients with severe cardiorespiratory insufficiency (NYHA cardiac function class III-IV); and ③ patients who could not cooperate with the examination. This study was approved by the Ethics Committee of medical ethics committee of zhangzhou hospital, fujian province (Ethics Approval Number: Zhang Medical Lun 2025LWB215).\u003c/p\u003e\n\u003ch3\u003e2. Cluster approach\u003c/h3\u003e\n\u003cp\u003eIn accordance with the European Thyroid Association of 2022 (EU-TIRADS) criteria [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], the nodules were categorized into group A (\u0026lt;\u0026thinsp;0.5 cm), group B (0.5\u0026thinsp;~\u0026thinsp;1.0 cm), and group C (\u0026gt;\u0026thinsp;1.0 cm) according to their size, and the cases in the in-plane (n\u0026thinsp;=\u0026thinsp;275) and out-of-plane (n\u0026thinsp;=\u0026thinsp;217) groups were extracted on the basis of historical data.\u003c/p\u003e\n\u003ch3\u003e3. Instruments and methods\u003c/h3\u003e\n\u003cp\u003eA Mindray Resona 8 color Doppler diagnostic ultrasound machine with a probe frequency of 8\u0026thinsp;~\u0026thinsp;12 MHz was used. Three equally qualified physicians performed ultrasound-guided fine-needle aspiration of the thyroid nodules. Patients were placed in the supine position, and the puncture sites were routinely sterilized. In the out-of-plane group, puncture was performed via the short-axis method, with the needle inserted approximately 5 mm parallel to the midpoint of the long axis of the probe, the ultrasound-guided tip of the needle was introduced into the nodule, and the thyroid nodule was aspirated via a 2 ml vacuum pressure load three times, with 10 rapid and small insertions each time (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). All three needle entry sites were different, and all were independent punctures. In the in-plane group, puncture was performed via the long-axis method, the needle was inserted approximately 5 mm beside the midpoint of the short axis of the probe, the ultrasound guided the needle tip into the nodule, and the thyroid nodule was aspirated via a vacuum pressure load of 2 ml, three times in total, with 10 rapid and small insertions each time, and the three needle insertion sites were all different (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe arrow shows that the tip of the needle is located within the nodule but is not as clearly displayed as the in-plane method of puncturing the needle.\u003c/p\u003e\n\u003cp\u003eThe arrow shows that the tip of the needle is located in the nodule, and the puncture needle is clearly visible.\u003c/p\u003e\n\u003ch3\u003e4. Observation indicators\u003c/h3\u003e\n\u003cp\u003eThe contents were smeared, fixed in 95% ethanol and stained with pasteurization. A single-blind method was used, i.e., the pathologist was unaware of the specimen taken from the plane of the puncture, and a senior pathologist was designated to refer to the Bethesda Reporting System for Thyroid Cytopathology, which is commonly used internationally, for a total of six categories [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]: I specimens that are undiagnostic or unsatisfactory; lI benign; III cellular atypical lesions of unknown significance; IV follicular or suspicious follicular neoplasms; and V suspected malignant neoplasms; and Vl malignant tumors. The main observations included the following: the specimen pass rate (at least 6 groups of benign or malignant cell populations) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) and the time of the puncture operation: from the beginning of the puncture to obtaining a satisfactory specimen.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\n\u003ch3\u003e5. Statistical methods\u003c/h3\u003e\n\u003cp\u003eSPSS 26.0 statistical software was used to analyze the data. Measurement data conforming to a normal distribution are expressed as the mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation, and a t test was used; count data are expressed as the frequency (n) or percentage (%), and a chi-square test was used (if the chi-square test requirements were not met, Fisher's exact probability method or successive correction method was used), and the data at the time of puncture were confirmed to conform to a normal distribution by the Shapiro‒Wilk test and t test. The t test was used for normally distributed data, and the median (\u003cem\u003eM\u003c/em\u003e) was used to describe nonnormally distributed data. Comparisons between two groups were made via the Mann‒Whitney test, and differences were considered statistically significant at P\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e"},{"header":"Results","content":"\n\u003ch3\u003e1. Analysis of baseline information\u003c/h3\u003e\n\u003cp\u003eThe baseline data of patients in each group (Group A: nodules\u0026thinsp;\u0026lt;\u0026thinsp;0.5 cm; Group B: 0.5 cm\u0026thinsp;\u0026le;\u0026thinsp;nodules\u0026thinsp;\u0026le;\u0026thinsp;1.0 cm; Group C: nodules\u0026thinsp;\u0026gt;\u0026thinsp;1.0 cm) were not significantly different between the two puncture methods (all p\u0026thinsp;\u0026gt;\u0026thinsp;0.05), indicating well-balanced groupings (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\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\u003eComparison of the baseline data of patients enrolled via the intraplanar and extraplanar puncture methods\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"10\"\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\u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBaseline data\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eGroup A (\u0026lt;\u0026thinsp;0.5 cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e\u003cp\u003eGroup B (0.5 cm\u0026thinsp;\u0026le;\u0026thinsp;X\u0026thinsp;\u0026le;\u0026thinsp;1.0 cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e\u003cp\u003eGroup C (\u0026gt;\u0026thinsp;1.0 cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eIn-plane (n\u0026thinsp;=\u0026thinsp;111)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eOutside the plane (n\u0026thinsp;=\u0026thinsp;29)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eStatistical/P value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eIn-plane (n\u0026thinsp;=\u0026thinsp;106)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eOutside the plane (n\u0026thinsp;=\u0026thinsp;54)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003eStatistical/p value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003eIn-plane (n\u0026thinsp;=\u0026thinsp;58)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eOutside the plane (n\u0026thinsp;=\u0026thinsp;134)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eStatistical/p value\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge/years x\u0026thinsp;\u0026plusmn;\u0026thinsp;s\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e51.7\u0026thinsp;\u0026plusmn;\u0026thinsp;11.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e49.6\u0026thinsp;\u0026plusmn;\u0026thinsp;9.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.895/0.372\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e63.5\u0026thinsp;\u0026plusmn;\u0026thinsp;3.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e50.9\u0026thinsp;\u0026plusmn;\u0026thinsp;13.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.88/0.38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e52.7\u0026thinsp;\u0026plusmn;\u0026thinsp;11.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e48.0\u0026thinsp;\u0026plusmn;\u0026thinsp;14.17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e1.82/0.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSex\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.11/0.292\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e2.63/0.11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.27/0.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eThe male sex\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFemininity\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e91\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e22\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e76\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e43\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e104\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNodule size/x\u0026thinsp;\u0026plusmn;\u0026thinsp;s\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.34\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.36\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-1.27/0.21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.69\u0026thinsp;\u0026plusmn;\u0026thinsp;0.14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.71\u0026thinsp;\u0026plusmn;\u0026thinsp;0.16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e-0.66/0.51\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e2.11\u0026thinsp;\u0026plusmn;\u0026thinsp;1.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e2.36\u0026thinsp;\u0026plusmn;\u0026thinsp;1.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e-1.37/0.17\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePosition\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.03/0.258\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.386/3.04\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.123/5.77\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFalling-rising Tone\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e48\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCentre\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e62\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDown\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIsthmus\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBorder\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.941/0.396\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.741/1.15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.166/5.08\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFitting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e64\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e102\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIrregular\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVague\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExtrathoracic invasion\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCalcification\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.906/0.016\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.969/0.548\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.665/2.39\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMicrocalcification\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eComet tail Phenomenon\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eA point-like strong echo with an unclear meaning\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSlight calcification\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePeripheral calcification\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eStructure\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.803/0.063\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.94/0.124\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.5712.01\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSubstance\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e106\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e44\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e89\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIts about substance\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCystic predominance\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSpina bifida cystica\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSpongy\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBlood flow grading\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.14/3.927\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.277/2.56\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.870.71\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLevel 0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e44\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLevel 1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e57\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e67\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLevel 2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLevel 3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003e2. Comparison of specimen satisfaction and cytologic diagnostic results of fine-needle aspiration biopsy between the two puncture methods\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThe satisfaction rate of specimen retrieval via the in-plane puncture method was significantly greater than that via the out-of-plane puncture method in Group A (98.2% and 65.5%, respectively) and Group B (98.1% and 81.2%, respectively) (both p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). However, in Group C, the difference in the specimen satisfaction rate between the two methods was not statistically significant (96.8% and 98.3%, respectively, p\u0026thinsp;=\u0026thinsp;0.29), which may be related to the fact that larger nodules were easier to localize. In addition, the proportions of Class I in the in-plane method were 1.8% and 1.9% in Groups A and B, respectively, which were significantly lower than those in the out-of-plane method (34.5% and 18.8%), and the difference was statistically significant (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of specimen satisfaction rates and cytological diagnosis results of in-plane and out-of-plane puncture\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\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\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFNAB cytological diagnosis results\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eGroup A (\u0026lt;\u0026thinsp;0.5 cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e\u003cp\u003eGroup B (0.5 cm\u0026thinsp;\u0026le;\u0026thinsp;X\u0026thinsp;\u0026le;\u0026thinsp;1.0 cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e\u003cp\u003eGroup C (\u0026gt;\u0026thinsp;1.0 cm)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSatisfactory rate of specimens in the plane (no. of cases/total)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSatisfactory rate of specimens outside the plane (number of cases/total number)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSatisfactory rate of specimens in the plane (no. of cases/total)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eSatisfactory rate of specimens outside the plane (number of cases/total number)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eSatisfactory rate of specimens in the plane (no. of cases/total)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003eSatisfactory rate of specimens outside the plane (number of cases/total number)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e98.2%(109/111)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e65.5%(19/29)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e98.1%(104/106)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e81.2%(44/54)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e96.6%(56/58)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e92.5%(124/134)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI class\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e10\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\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eⅡ class\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e75\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eⅢ class\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eⅣ class\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0\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\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eV class\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eⅥ class\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e27\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eamount to\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e111\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e106\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e54\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e58\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e134\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eP price\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003csup\u003e#\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e\u003cp\u003e0.29**\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"7\"\u003eNote: *: Comparison of the satisfaction rates between the in-plane method and out-of-plane methods in Group A; #: Comparison of the satisfaction rates between the in-plane method and out-of-plane methods in Group B; **: Comparison of the satisfaction rates between the in-plane method and out-of-plane methods in Group C.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\n\u003cdiv class=\"Heading\"\u003e3. \u003cb\u003eComplex anatomical location subgroup analysis\u003c/b\u003e\u003c/div\u003e\u003cp\u003eIn group A (\u0026lt;\u0026thinsp;0.5 cm), group B (0.5\u0026thinsp;~\u0026thinsp;1.0 cm) and group C (\u0026gt;\u0026thinsp;1.0 cm), further sieving of the selection of nodes adjacent to blood vessels/trachea (distance\u0026thinsp;\u0026lt;\u0026thinsp;2 mm) was performed: for group A (\u0026lt;\u0026thinsp;0.5 cm), the specimen satisfaction rate of the in-plane method was significantly greater than that of the out-of-plane method (94.4% vs. 50.0%, p\u0026thinsp;=\u0026thinsp;0.02), and the complication rate was significantly lower than that of the out-of-plane method (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05), suggesting that, for very small nodes, the in-plane method in a complex location still allows for Group B (0.5\u0026thinsp;~\u0026thinsp;1.0 cm): the specimen satisfaction rate of the in-plane method remained high (95.7% vs. 66.7%, p\u0026thinsp;=\u0026thinsp;0.02), further validating the stability of its technique. In Group C (\u0026gt;\u0026thinsp;1.0 cm), although the difference in the specimen satisfaction rate between the two puncture methods was not statistically significant, the complication rate of the in-plane method was significantly greater than that of the out-of-plane method (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). statistically significant (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of puncture effect and complications of complex location nodules in each group\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\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\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGroup\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMetric\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eThe plane method\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eThe plane-out method\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eP price\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGroup A (\u0026lt;\u0026thinsp;0.5 cm, n\u0026thinsp;=\u0026thinsp;18)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSpecimen satisfaction rate (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e94.4(17/18)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e50.0(2/4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.02\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eHematoma incidence (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.6(1/18)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e25.0(2/4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.02\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGroup B (0.5-1.0 cm, n\u0026thinsp;=\u0026thinsp;23)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSpecimen satisfaction rate (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e95.7(22/23)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e66.7(8/12)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.02\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eHematoma incidence (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4.3(1/23)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e16.7( 4/12)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.02\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGroup C (\u0026gt;\u0026thinsp;1.0 cm, n\u0026thinsp;=\u0026thinsp;62)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSpecimen satisfaction rate (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e84.6(11/13)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e97.1(34/35)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.11\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eHematoma incidence (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e15.4(2/13)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0(0/35)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.02\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\n\u003ch3\u003e4. Comparison of the puncture time between the two puncture methods\u003c/h3\u003e\n\u003cp\u003eThe mean operating time for the in-plane method for nodules\u0026thinsp;\u0026le;\u0026thinsp;1.0 cm was 4.10\u0026thinsp;\u0026plusmn;\u0026thinsp;1.0 minutes, which was shorter than the 5.50\u0026thinsp;\u0026plusmn;\u0026thinsp;2.3 minutes for the out-of-plane method (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), whereas the mean operating time for the out-of-plane method for complex location nodules (adjacent to blood vessels/trachea)\u0026thinsp;\u0026gt;\u0026thinsp;1.0 cm was 4.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.1 minutes, which was shorter than the 5.8\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5 minutes for the out-of-plane method (p\u0026thinsp;=\u0026thinsp;0.003).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe difference in diagnostic efficacy between the modes of operation (in-plane versus out-of-plane) of ultrasound-guided fine-needle aspiration biopsy (FNAB), a core technique for diagnosing the benign and malignant nature of thyroid nodules, has been a focus of research. By comparing the diagnostic efficacy of the two puncture techniques, the results of this study revealed that the in-plane method of FNAB demonstrated significant advantages for identifying thyroid nodules\u0026thinsp;\u0026le;\u0026thinsp;1.0 cm in size. Specifically, the performance of the in-plane method FNAB was significantly greater than that of the out-of-plane method in terms of specimen satisfaction and operative time advantage in both Group A (\u0026lt;\u0026thinsp;0.5 cm) and Group B (0.5\u0026thinsp;~\u0026thinsp;1.0 cm) (both p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). By keeping the needle parallel to the long axis of the ultrasound probe, the in-plane technique allows the complete path of the needle from the skin to the target (\"proximal-to-distal\" approach) to be tracked in real time on the ultrasound image, which is particularly suitable for scenarios requiring precise penetration of multilayered tissues or avoidance of important structures and reduces the need for repeated adjustments of the needle tip position, whereas the out-of-plane method requires repeated adjustments of the angle of the needle during the procedure [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe results of this study show that the advantage of the in-plane method of FNAB is significant size dependence. For nodules\u0026thinsp;\u0026le;\u0026thinsp;1.0 cm, the in-plane method demonstrated a significant advantage over the real-time tip full visualization technique, and even with adjacent vessels/trachea (distance\u0026thinsp;\u0026lt;\u0026thinsp;2 mm), the in-plane method still had a high rate of specimen satisfaction of 94.4% and 95.7% (both p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) in complex locations in groups A and B, which was significantly better than that of the out-of-plane method (50.0% and 66.7%). The out-of-plane method had a high hematoma incidence of 25% in complex locations (0% in the in-plane method, p\u0026thinsp;=\u0026thinsp;0.13), and the nodule size may be a central factor influencing the choice of puncture technique[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e], with very small nodules requiring preference for the in-plane technique to avoid risk. The results of the present study also revealed that the in-plane method significantly reduced the proportion of Bethesda system category I (undiagnostic) nodules\u0026thinsp;\u0026le;\u0026thinsp;1.0 cm (group A: 1.8% vs. 34.5%; group B: 1.9% vs. 18.8%, both p\u0026thinsp;\u0026lt;\u0026thinsp;0.05), thus reducing the risk of repeat puncture due to insufficient samples. This finding not only validates the clinical value of real-time visualization but also agrees with the tip path optimization model proposed by Muzzammil et al. [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], which suggests that the in-plane method can accurately obtain the cellular components of the nodule by displaying the tip position throughout the entire process and combining it with a cutting-type needle insertion pattern, avoiding interference from the surrounding tissues [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e], whereas the out-of-plane method may lead to a reduction in the number of puncture specimens in the nodule due to the lack of tip visibility. Inadequate visualization of the needle tip may lead to the need for repeated adjustments of the needle direction during small nodule puncture, increasing the risk of local tissue injury.\u003c/p\u003e\u003cp\u003eNotably, the out-of-plane approach did not cause any complications in complex nodules\u0026thinsp;\u0026gt;\u0026thinsp;1.0 cm, which is consistent with the study of Sun et al.[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. that larger nodules provide a wider manipulation space, which further reduces the difficulty of the out-of-plane approach in complex anatomical locations, and that the out-of-plane approach, by using the probe's long-axis paracentesis to enter the needle, can approach the surface of the nodule at a smaller angle to avoid excessive penetration of the needle tip and thus reduce the probability of contact between the needle tip and deep vascular structures. In addition, the out-of-plane approach, which uses the long axis of the probe to access the needle, is able to approach the nodule surface at a smaller angle for nodules close to the trachea, carotid artery, or dorsal thyroid, avoiding excessive penetration of the needle tip and thus reducing the probability of the tip contacting deep vascular structures [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e] and lowering the risk of complications.\u003c/p\u003e\u003cp\u003eIn addition, this study revealed that the in-plane method has a timeliness advantage for nodules\u0026thinsp;\u0026le;\u0026thinsp;1.0 cm and that the out-of-plane method has an advantage for complex location nodules\u0026thinsp;\u0026gt;\u0026thinsp;1.0 cm. Limitations of this study include the potential bias of its retrospective design and the noninclusion of molecular marker analysis. Future multicenter prospective studies are needed to optimize puncture path planning by combining elastography or artificial intelligence techniques and to explore the role of molecular markers such as BRAF V600E in individualized strategies.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn summary, a stepped strategy based on nodule size can balance the efficacy and safety of FNAB. Nodules\u0026thinsp;\u0026le;\u0026thinsp;1.0 cm in size: Regardless of their location, the in-plane approach is preferred, with significant advantages in terms of its high satisfaction rate and low hematoma risk. \u0026gt;1.0 cm nodule: flexible choice for noncomplicated locations; if adjacent to vessels/trachea, an out-of-plane approach is recommended to balance safety and efficiency.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch3\u003eAcknowledgments\u003c/h3\u003e\n\u003cp\u003eWe would like to thank the entire Department of Ultrasound for their help and support.\u003c/p\u003e\n\u003ch3\u003eAuthor contributions\u0026nbsp;\u003c/h3\u003e\n\u003cp\u003eDesign of the work\u0026mdash;XT and MC. Article retrieval and data collection\u0026mdash;CZ\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eand YW. Article selection\u0026mdash;XTand CZ. Data analysis, code writing and\u0026nbsp;\u003c/p\u003e\n\u003cp\u003emapping\u0026mdash;XT and MC. Supervision conducted and responsibility for the\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eentire study\u0026mdash;XT. Drafting the manuscript and revising it\u0026mdash;all authors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo specific funding for this research.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used in this study are available from the corresponding author upon request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eApproved by the Ethics Committee of Fujian Zhangzhou Hospital: the study uses previously collected and archived clinical data, poses no more than minimal risk, and safeguards participant privacy and rights; thus, informed consent was waived.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot required.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eTang JW, Mou JY, Chen J, et al. Discrimination of benign and malignant thyroid nodules through comparative analyses of human saliva samples via metabolomics and deep-learning-guided label-free sers. ACS Appl Mater Interfaces. 2025;17(3):5538-5549. https://doi.org/10.1021/acsami.4 c20503.\u003c/li\u003e\n\u003cli\u003eUshakov AV. Stages of benign thyroid nodules: principles and ultrasound signs. Quant Imaging Med Surg. 2024;14(8):6108-6122. https://doi.org/10.21037/qims-24-477.\u003c/li\u003e\n\u003cli\u003eDu H, Chen F, Li H, et al. Deep-learning radiomics based on ultrasound can objectively evaluate thyroid nodules and assist in improving the diagnostic level of ultrasound physicians. Quant Imaging Med Surg. 2024;14(8):5932-5945. doi:10.21037/qims-23-1597.\u003c/li\u003e\n\u003cli\u003ede Matos MLG, Pinto M, Gon\u0026ccedil;alves A, Canberk S, Bugalho MJM, Soares P. Insights in biomarkers complexity and routine clinical practice for the diagnosis of thyroid nodules and cancer. PeerJ. 2025;13:e18801. Published 2025 Jan 20. https://doi.org/10.7717/peerj.18801.\u003c/li\u003e\n\u003cli\u003eGowardhan V, Valand A. A cytohistologic correlation study of thyroid lesions: evaluation of diagnostic accuracy and pitfalls of fine needle aspiration cytology. cureus. 2024;16(3):e55748. Published 2024 Mar 7. https://doi.org/10.7759/cureus.55748.\u003c/li\u003e\n\u003cli\u003eLin H, Zhang X, Yan N, et al. Diagnosis and treatment of a rare bilateral primary thyroid cancer: a case report. Front Oncol. 2025;14:1468550. published 2025 Feb 13. https://doi.org/10.3389/fonc.2024.1468550.\u003c/li\u003e\n\u003cli\u003eZhang C, Liu ZL, Wei ZH, Lu Q. The value and sensitivity of contrast-enhanced ultrasonography combined with fine-needle aspiration biopsy in the diagnosis of thyroid nodules. Sci Rep. 2024;14(1):29633. Published 2024 Nov 28. https://doi.org/10.1038/s41598-024-80447-6.\u003c/li\u003e\n\u003cli\u003eFerraz C. Molecular testing for thyroid nodules: where are we now? Rev Endocr Metab Disord. 2024;25(1):149-159. https://doi.org/10.1007/s11154-023 -09842-0\u003c/li\u003e\n\u003cli\u003eDurante C, Heged\u0026uuml;s L, Na DG, et al. International expert consensus on us lexicon for thyroid nodules. Radiology. 2023;309(1):e231481. https://doi.org /10.1148/radiol.231481.\u003c/li\u003e\n\u003cli\u003eRoberts D, Murray T\u0026Eacute;, Rattan B, Murphy DT, Cresswell M. How to Approach a Hip PARTI With Confidence: Ultrasound-Guided Parallel Transverse in-Plane Technique for Intra-articular Hip Interventions. J Ultrasound Med. 2021;40(10):2219-2223. doi:10.1002/jum.15608.\u003c/li\u003e\n\u003cli\u003ePirri C, Zabotti A, Pirri N, et al. Ultrasound-guided core needle biopsy of deep fascia: a cadaveric study evaluating feasibility, accuracy and reliability. Clin Anat. 2025;38(2):146-157. doi:10.1002/ca.24224.\u003c/li\u003e\n\u003cli\u003eRaed Farhat , Majd Asakla , Leemor Wallach, et al. US-guided FNA techniques for thyroid nodules is the short axis better than the long axis?Am J Otolaryngol . 2022 Sep-Oct;43(5):103593. https://doi.org/10.1016/j.amjoto.2022.103593.\u003c/li\u003e\n\u003cli\u003eCohn S, Farhat R, El Khatib N, et al. Thyroid US-guided FNA techniques: a prospective, randomized controlled study. Am J Otolaryngol. 2024;45(1):104091 . https://doi.org/10.1016/j.amjoto.2023.104091.\u003c/li\u003e\n\u003cli\u003eChoi JW, Lee HJ, Nam YS, et al. Optimizing injection accuracy for Baxter\u0026apos;s nerve entrapment: an ultrasonography-guided approach based on anatomical surface landmarks. Ann Med. 2025;57(1):2450525. doi:10.1080/07853890.2025.2450525\u003c/li\u003e\n\u003cli\u003eSi CF, Yu J, Cui YY, Huang YJ, Cui KF, Fu C. Comparison of diagnostic performance of the current score-based ultrasound risk stratification systems according to thyroid nodule size. Quant Imaging Med Surg. 2024;14(12):9234-9245. doi:10.21037/qims-24-282.\u003c/li\u003e\n\u003cli\u003eKim E, Pudhucode R, Chen H, Lindeman B. Discordance between the american thyroid association and the american college of radiology guideline systems for thyroid nodule biopsy. J Surg Res. 2020;255:469-474. doi:10.1016/j.jss.2020.05.074\u003c/li\u003e\n\u003cli\u003eLee B, Na DG, Kim JH. Malignancy risk stratification and subcategorization of K-TIRADS intermediate suspicion thyroid nodules: a retrospective multicenter study. Ultrasonography. 2024;43(2):132-140. doi:10.14366/usg.23203.\u003c/li\u003e\n\u003cli\u003eRicci V, Mezian K, Chang KV, et al. Ultrasound-guided injection of the elbow: cadaveric description for the proximal to distal approach. PM R. 2023;15(11):1431-1435. https://doi.org/10.1002/pmrj.12966.\u003c/li\u003e\n\u003cli\u003eCheong I, Otero Castro V, Feijoo J, M\u0026aacute;rmol PDB, Tamagnone FM. Short axis in-plane ultrasound-guided technique for internal jugular vein cannulation. j Emerg Med. 2023;64(4):488-490. https://doi.org/10.1016/j.jemermed.2023.02.017.\u003c/li\u003e\n\u003cli\u003eMuzzammil HM, Zhang YD, Ejaz H, Yuan Q, Muddassir M. A review on tissue-needle interaction and path planning models for bevel tip type flexible needle minimal intervention. Math Biosci Eng. 2024 Jan;21(1):523-561. https://doi.org/10.3934/mbe.2024023.\u003c/li\u003e\n\u003cli\u003eMaloney ME, Potter CT, Chun BD, Montilla RD, Schanbacher CF. Comparative analysis of taper point and reverse cutting needles on skin puncture force. Dermatol Surg. 2025 Feb 1;51(2):144-147. https://doi.org/10.1097/DSS.0000000000004401.\u003c/li\u003e\n\u003cli\u003eSun XX, Lv M, Du WY, Liu Y, Zhang H, Wang YL. Comparison of out-of-plane short axis with in-plane long axis for ultrasound-guided radial arterial cannulation: a systematic review with trial sequential analysis of randomized controlled trials [published correction appears in Front Cardiovasc Sci. cannulation: a systematic review with trial sequential analysis of randomized controlled trials [published correction appears in Front Cardiovasc Med. 2023 Apr 04;10:1191088. doi: 10.3389/fcvm.2023.1191088.]. Front Cardiovasc Med. 2022;9:983532. Published 2022 Oct 12. https://doi.org/10.3389/fcvm.2022.983532.\u003c/li\u003e\n\u003cli\u003eEvans M, Kang S, Bajaber A, Gordon K, Martin C 3rd. Augmented reality for surgical navigation: a review of advanced needle guidance systems for percutaneous tumor ablation. Radiol Imaging Cancer. 2025 Jan;7(1):e230154. https://doi.org/10.1148/rycan.230154.\u003c/li\u003e\n\u003cli\u003eHaddad RI, Bischoff L, Ball D, et al. Thyroid carcinoma, version 2.2022, NCCN clinical practice guidelines in oncology.J Natl Compr Canc Netw. 2022 Aug. 20(8):925-951. https://doi.org/10.6004/jnccn.2022.0040.\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":"thyroid nodule, ultrasound-guided fine-needle aspiration biopsy, individualized aspiration strategy, complication","lastPublishedDoi":"10.21203/rs.3.rs-7026688/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7026688/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo compare the clinical efficacy of ultrasound-guided in-plane versus out-of-plane fine-needle aspiration biopsy techniques for identifying thyroid nodules of different sizes and to explore individualized aspiration strategies on the basis of nodule size.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eA total of 492 patients who underwent ultrasound-guided fine-needle aspiration biopsy of thyroid nodules from January 2024 to February 2025 were retrospectively included and divided into an in-plane group (n = 275) and an out-of-plane group (n = 217) according to nodule size (group A: \u0026lt;0.5 cm; group B: 0.5 ~ 1.0 cm; group C: \u0026gt;1.0 cm), and the two groups were compared in terms of the satisfaction rates of the specimens, operation times and complication differences and further stratified to analyze the effects of complex anatomical locations (adjacent vessels/trachea).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe advantage of the in-plane method was significant for ≤ 1.0 cm nodules, with overall specimen satisfaction rates of 98.2% and 98.1% in Groups A and B, respectively, which were significantly greater than those of the out-of-plane method (65.5% and 81.2%, respectively), with a significantly lower percentage of Bethesda Class I nodules (Group A: 1.8% vs. 34.5%; Group B: 1.9% vs. 18.8%) and a significantly lower complication rate in Group A than in the out-of-plane method for complex-location (neighboring vessel/trachea) nodules. The complication rate was lower in Group A for the in-plane approach than for the out-of-plane approach, and the differences were statistically significant (P \u0026lt; 0.05). For \u0026gt; 1.0 cm nodules, there was no statistically significant difference in the overall specimen satisfaction rate between the two puncture methods (96.8% and 98.3%, respectively, p = 0.29), but the out-of-plane method had a higher specimen satisfaction rate in complex locations (adjacent vessels/trachea) (97.1% vs. 84.6%, p = 0.038), and the complication rate was lower (15.4% for the in-plane method vs. 0% for the out-of-plane approach, p = 0.02). The mean puncture time was shorter for the in-plane method than for the out-of-plane method for ≤ 1.0 cm nodules (4.10 ± 1.0 min, 5.50 ± 2.3 min, respectively, p \u0026lt; 0.001) but shorter for the out-of-plane method than for the in-plane method for \u0026gt; 1.0 cm nodes with complex locations (adjacent to the blood vessels/trachea) (4.2 ± 1.1 minutes, 5.8 ± 1.5 minutes, p \u0026lt; 0.001).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe in-plane approach is preferred for ≤ 1.0 cm nodules; the noncomplicated location of \u0026gt; 1.0 cm nodules allows for flexibility, and the out-of-plane approach is recommended to balance efficiency and safety if adjacent to blood vessels/trachea.\u003c/p\u003e","manuscriptTitle":"Size-Dependent Strategy for Ultrasound-Guided Fine-Needle Aspiration Biopsy of Thyroid Nodules: A Comparison of In-Plane and Out-of-Plane Techniques","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-04 08:37:42","doi":"10.21203/rs.3.rs-7026688/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":"a709d0fe-5af8-471c-b7cf-11bb85862fba","owner":[],"postedDate":"August 4th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-03-18T10:11:37+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-04 08:37:42","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7026688","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7026688","identity":"rs-7026688","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}