Division of Endocrine Surgery, Department of General Surgery, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye.
Division of Endocrine Surgery, Department of General Surgery, Sisli Hamidiye Etfal Training and Research Hospital, University of Health Sciences Turkey, Istanbul, Türkiye.
Front Endocrinol (Lausanne). 2024 Sep 20;15:1420697. doi: 10.3389/fendo.2024.1420697. eCollection 2024.
The objective of this study was to characterize the electrophysiological characteristics of nonrecurrent inferior laryngeal nerves (NRILNs) that were dissected via intraoperative neuromonitoring (IONM) and concomitant vascular anomalies in patients with NRILNs.
A retrospective analysis was conducted on 7865 patients who underwent thyroidectomy with IONM at three tertiary referral centers. The study included 42 patients in whom an NRILN was detected. IONM data and postoperative vocal cord (VC) examinations were recorded for all patients. The absence of an initial vagal EMG response and/or a short (<3.5 ms) latency period during the initial vagal stimulation or the inability to identify the RLN within the Beahrs triangle was considered highly suspicious for the presence of an NRILN. Postoperative cross-sectional imaging was performed in 36 out of 42 patients to assess any concurrent vascular anomalies.
The prevalence of NRILN was 0.53%. An NRILN was suspected due to EMG findings in 32 (76%) patients and the inability to identify the RLN within the Beahrs triangle in the remaining 10 (24%) patients. The mean right VN latency period was 3.05 ± 0.15 ms. The V1 latency period of the right VN was shorter than 3.5 ms in 39 (93%) and longer than 3.5 ms in 3 (7%) patients. One of these three patients with latency>3.5ms had a large mediastinal goiter. Transient VC paralysis occurred in one (2.4%) patient. Of the 36 patients with postoperative imaging data, 33 (91.4%) had vascular anomalies. All 33 patients had aberrant right subclavian arteries, and 13 (39.4%) also had accompanying additional vascular anomalies.
The NRILN is an anatomical variation that increases the risk of nerve injury. Observation of an absent EMG response and/or a short latency period during the initial vagal stimulation facilitates the detection of an NRILN at an early stage of thyroidectomy in the majority of patients.
本研究旨在对术中神经监测（IONM）时发现的伴发血管异常的非返性喉返神经（NRILN）的电生理特征进行分析。
对在三个三级转诊中心行甲状腺切除术并接受 IONM 的 7865 例患者进行回顾性分析。该研究纳入 42 例检测到 NRILN 的患者。所有患者均记录 IONM 数据和术后声带（VC）检查。在最初的迷走神经刺激过程中，如果没有初始的迷走神经肌电图反应和/或潜伏期较短（<3.5ms），或者无法在 Beahrs 三角内识别 RLN，则高度怀疑存在 NRILN。42 例患者中有 36 例行术后横断面成像，以评估是否存在伴发血管异常。
NRILN 的患病率为 0.53%。32 例（76%）患者因肌电图发现而怀疑存在 NRILN，其余 10 例（24%）患者则因无法在 Beahrs 三角内识别 RLN 而怀疑存在 NRILN。右侧 VN 的平均 VN 潜伏期为 3.05±0.15ms。39 例（93%）右侧 VN 的 V1 潜伏期<3.5ms，3 例（7%）>3.5ms。这 3 例潜伏期>3.5ms 的患者中，有 1 例为纵隔巨大甲状腺肿。1 例（2.4%）患者出现一过性 VC 麻痹。在 36 例有术后影像学资料的患者中，33 例（91.4%）存在血管异常。所有 33 例患者均存在异常右锁骨下动脉，其中 13 例（39.4%）还伴有其他血管异常。
NRILN 是一种增加神经损伤风险的解剖变异。在大多数患者中，观察到初始迷走神经刺激时没有肌电图反应和/或潜伏期较短，有助于在甲状腺切除术早期发现 NRILN。
