喉上神经内支于梨状窝的内镜解剖研究

Endoscopic anatomical study of the internal branch of the superior laryngeal nerve in the pyriform fossa

摘要:

目的 通过对离体喉进行内镜下梨状窝区喉上神经内支(ibSLN)的解剖，分析总结其在内镜下的喉内解剖学特点，为咽喉肿瘤的内镜手术提供解剖学依据。方法 选择8具(16侧)已经完成动静脉灌注的尸头进行离体喉制备。将左右两侧颈鞘、舌骨、舌、颈段食管气管、带状肌、咽部及喉体整体取下制备离体喉。将离体喉固定于特制喉体固定支架；通过在内镜下解剖离体喉内的ibSLN，并分析解剖数据：①ibSLN在内镜视野下的入喉位置；②在喉内的分支类型；③识别相应解剖标志。结果 在离体喉的内镜下解剖中，总结ibSLN在喉内入喉处的规律：①8具(16侧)尸头ibSLN在梨状窝外侧壁的入喉位置无明显差异；②16侧ibSLN均在梨状窝外侧壁，甲状软骨上缘的梨状窝三角外侧边的后1/3处入喉；③16侧ibSLN在喉内均分离出3个分支，上中支分布于声门上，下支分布于梨状窝。结论 离体喉的制备有利于进行内镜下的下咽部解剖；内镜下ibSLN于梨状窝可通过探寻相对固定的解剖标志进行识别，有望通过在内镜下对ibSLN进行解剖分离保护，以提高患者术后的吞咽功能。

Abstract:

Objective Through endoscopic dissection of the internal branch of the superior laryngeal nerve(ibSLN) in the pyriform fossa region of exvivo larynges, this study analyzes and summarizes its endoscopic anatomical features, providing an anatomical basis for endoscopic surgery of pharyngolaryngeal tumors. Methods Eight cadaveric heads that had completed arteriovenous perfusion were selected for preparation of the isolated larynx. The bilateral cervical sheaths, hyoid bone, tongue, cervical segment of the esophagus and trachea, strap muscles, pharynx, and laryngeal body were removed as a whole to prepare an isolated larynx. The isolated larynx was fixed to a specially designed laryngeal body fixation bracket. By dissecting the ibSLN in the isolated larynx under the endoscope, the following anatomical data were collected and analyzed: ①the position of ibSLN entering the larynx under the endoscopic field of view. ②the type of branching within the larynx. ③identification of the corresponding anatomical landmarks. Results ①In the endoscopic dissection of the isolated larynx of the 8 speciemens, there was no significant difference in the entry position of the ibSLN on the lateral wall of the pyriform fossa between the left and right sides. ②The position of ibSLN entering the larynx was located on the lateral wall of the pyriform fossa, at the posterior 1/3 (0.66±0.09) of the lateral border of the pyriform fossa triangle above the superior edge of the thyroid cartilage. ③Three branches were identified within the larynx on all the 16 sides of the ibSLN. The upper and middle branches were distributed in the supraglottic region, while the lower branch was distributed in the pyriform fossa. Conclusion Preparation of the isolated larynx facilitates the performance of endoscopic hypopharyngeal dissection. Under endoscopy, the ibSLN in the pyriform fossa can be identified by exploring relatively fixed anatomical landmarks. It is expected that postoperative swallowing function of patients can be improved by performing anatomical dissection and protection of the ibSLN under endoscopy.