右侧甲状腺腺叶切除术中遇到的具有双支模式并重新汇合的非返喉神经：一种罕见的解剖变异

文献信息

中文摘要

背景： 非返喉神经（NRLN）是一种不常见的解剖变异，它直接从迷走神经走行至喉部，而不经过通常的返折环；约百分之一的人群中出现在右侧，左侧则罕见得多。识别该变异对安全的甲状腺手术至关重要，因为未预料到的NRLN位于意外位置，容易受到意外损伤。我们报告一例右侧非返喉神经，具有不寻常的双支形态，神经分叉后在进入喉部之前又重新汇合。
病例介绍： 一名50多岁女性因右叶良性、压迫性多结节性甲状腺肿接受右侧甲状腺腺叶切除术。术中，在预期的气管食管沟内未发现返喉神经；在颈动脉鞘内系统追踪迷走神经，发现右侧NRLN分为上支和下支。两支走行不同路径，并在经环甲膜进入喉部前约10 mm处重新汇合为单一主干。两支均被识别并保留。患者顺利拔管，声带功能正常，恢复无并发症，早期及后期随访均无声音改变。
结论： 双支NRLN在进入喉部前分支重新汇合是一种我们此前未见过描述的形态；虽然已有非返神经喉外分叉的报道，但随后的重新汇合增加了神经识别和保留的复杂性。认识到非返神经可能分支并重新汇合，应促使在甲状腺手术中对从迷走神经追踪的每一神经束进行完整追踪。

英文摘要

BACKGROUND: The non-recurrent laryngeal nerve (NRLN) is an uncommon anatomical variant that passes directly from the vagus nerve to the larynx without the usual recurrent loop; it occurs on the right side in around one in a hundred individuals and is considerably rarer on the left. Its recognition is central to safe thyroid surgery, because an unanticipated NRLN lies in an unexpected position and is vulnerable to inadvertent injury. We report a right non-recurrent laryngeal nerve with an unusual dual-branch morphology in which the nerve divided and then re-merged before laryngeal entry.
CASE PRESENTATION: A woman in her 50s underwent right hemithyroidectomy for a benign, compressive multinodular goitre of the right lobe. Intraoperatively, no recurrent laryngeal nerve was found in the expected tracheo-oesophageal groove; systematic tracing of the vagus nerve within the carotid sheath revealed a right NRLN that divided into a superior and an inferior branch. The two branches followed separate courses and re-merged into a single trunk approximately 10 mm before entering the larynx through the cricothyroid membrane. Both branches were identified and preserved. The patient was extubated uneventfully, demonstrated normal vocal cord function, and made an uncomplicated recovery with no voice change at early or later follow-up.
CONCLUSION: Dual-branch NRLN in which the branches re-merge before laryngeal entry is a pattern we have not found previously described; while extra-laryngeal division of a non-recurrent nerve has been reported, the subsequent re-merging adds complexity to nerve identification and preservation. Awareness that a non-recurrent nerve may branch and re-merge should prompt complete tracing of every fascicle followed from the vagus during thyroid surgery.