Department of Otolaryngology - Head and Neck Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Municipal Hsiao-Kang Hospital, Kaohsiung Medical University, No. 100, Tzyou First Road, Kaohsiung City, 807, Taiwan.
World J Surg. 2010 Feb;34(2):223-9. doi: 10.1007/s00268-009-0316-8.
The lack of standardized procedures of intraoperative neuromonitoring (IONM) during thyroid operations may lead to highly variable results, and many of these results can cause misleading information and, conversely, increase the risk of recurrent laryngeal nerve (RLN) injury. Therefore, standardization of IONM procedures is necessary.
A total of 289 patients (435 nerves at risk) who underwent thyroidectomy by the same surgeon were enrolled in this study. Each patient was intubated with EMG endotracheal tube by the same anesthesiologist. Standardized IONM procedures were applied in each patient. The procedures include preoperative and postoperative video-recording of vocal cord movement, ensuring the correct position of electrodes after the neck was placed at full extension, vagal stimulation and registration of EMG signals before and after RLN dissection, and photographic documentation of the exposed RLN.
Five patients encountered dysfunction of IONM, which was caused by malposition of electrodes and the problem was detected at once. One patient with non-RLN was detected at the earlier stage of operation. Eighteen nerves experienced loss of EMG signals during thyroid dissection, and the causes of nerve injuries were well elucidated with the application of our standardized IONM procedures.
The standardized IONM procedures are useful and helpful not only to eliminate false IONM results, but also to elucidate the mechanism of RLN injury. After ascertaining the surgical pitfalls and improving the surgical techniques, the palsy rate was significantly reduced in this study.
甲状腺手术中术中神经监测（IONM）缺乏标准化程序可能导致结果差异很大，其中许多结果可能导致误导信息，反而增加喉返神经（RLN）损伤的风险。因此，有必要规范 IONM 程序。
本研究共纳入 289 例（435 根高危神经）由同一位外科医生行甲状腺切除术的患者。每位患者均由同一位麻醉师插入肌电图（EMG）气管内导管。每位患者均应用标准化的 IONM 程序。这些程序包括声带运动的术前和术后录像、确保颈部完全伸展后电极的正确位置、RLN 解剖前后的迷走神经刺激和 EMG 信号的记录，以及暴露的 RLN 的摄影记录。
有 5 例患者出现 IONM 功能障碍，这是由于电极位置不当引起的，问题一经发现便立即得到解决。1 例非 RLN 患者在手术早期被发现。18 根神经在甲状腺解剖过程中出现 EMG 信号丢失，应用我们的标准化 IONM 程序很好地阐明了神经损伤的原因。
标准化的 IONM 程序不仅有助于消除虚假的 IONM 结果，还有助于阐明 RLN 损伤的机制。在确定手术难点并改进手术技术后，本研究中的麻痹发生率显著降低。
