Service d'ORL et de Chirurgie cervico-faciale, hôpital de la Pitié-Salpêtrière, 50-52, boulevard Vincent-Auriol, 75013 Paris, France; Clinique Bizet, 21, rue Georges-Bizet, 75116 Paris, France.
Service d'ORL et de Chirurgie cervico-faciale, hôpital de la Pitié-Salpêtrière, 50-52, boulevard Vincent-Auriol, 75013 Paris, France; Inserm, unité de réhabilitation chirurgicale mini-invasive et robotisée de l'audition, UPMC, Sorbonne universités, université Pierre-et-Marie-Curie-Paris 6, 4, place Jussieu, 75252 Paris cedex 05, France.
Eur Ann Otorhinolaryngol Head Neck Dis. 2017 Apr;134(2):77-82. doi: 10.1016/j.anorl.2016.11.003. Epub 2016 Dec 27.
The aim of the study was to stimulate the vagal and the recurrent laryngeal nerves during and after thyroidectomy or parathyroidectomy, to record muscle responses, interpret the electrophysiological modifications and identify prognostic factors for postoperative vocal fold mobility.
A prospective study monitored 151 vagal nerves and 144 recurrent laryngeal nerves in 114 patients. Seven patients (14 vagal nerves) underwent continuous monitoring via an automatic periodic stimulation (APS) electrode. In 15 patients (21 vagal nerves), the stimulation threshold was studied. Muscle response was recorded on direct vagal and/or recurrent laryngeal nerve stimulation by a monopolar electrode or direct repeated stimulation via an electrode on the vagal nerve. In case of signal attenuation on the first operated side, surgery was not extended to the contralateral side.
The vagal nerve stimulation checked inferior laryngeal nerve integrity and recurrent status, without risk of false negatives. The vagal nerve stimulation threshold, before and after dissection, that induced a muscle response of at least 100μV ranged from 0.1 to 0.8mA. Similarity between pre- and post-dissection responses to supramaximal stimulation, defined as 1mA, on the one hand, and between post-dissection vagal and laryngeal recurrent nerve responses on the other correlated with normal postoperative vocal cord mobility. Conversely, muscle response attenuation below 100μV and increased latency indicated a risk of vocal fold palsy.
Vagal nerve stimulation allows suspicion or elimination of lesions on the inferior laryngeal nerve upstream of the stimulation point and detection of non-recurrent inferior laryngeal nerve. Intermittent monitoring assesses nerve function at the moment of stimulation, while continuous monitoring detects the first signs of nerve injury liable to induce postoperative recurrent nerve palsy. When total thyroidectomy is indicated, signal attenuation on the first operated side casts doubt on continuing surgery to the contralateral side in the same step.
本研究旨在刺激甲状腺或甲状旁腺切除术中及术后的迷走神经和喉返神经，记录肌肉反应，解释电生理变化，并确定术后声带活动度的预后因素。
一项前瞻性研究监测了 114 例患者的 151 条迷走神经和 144 条喉返神经。7 例（14 条迷走神经）通过自动周期性刺激（APS）电极进行连续监测。在 15 例患者（21 条迷走神经）中，研究了刺激阈值。通过单极电极直接刺激迷走神经和/或喉返神经，或通过迷走神经上的电极重复刺激，记录肌肉反应。如果对侧手术信号衰减，则不对该侧进行手术。
迷走神经刺激检查了喉返神经的完整性和复发性，且无假阴性风险。刺激前和刺激后，引起至少 100μV 肌肉反应的迷走神经刺激阈值范围为 0.1 至 0.8mA。刺激前和刺激后对 1mA 超强刺激的反应相似，以及对侧迷走神经和喉返神经的反应相似，与术后声带正常活动相关。相反，肌肉反应衰减低于 100μV 和潜伏期增加表明声带麻痹的风险。
迷走神经刺激可以怀疑或排除刺激点上游的喉返神经损伤，并检测非复发性喉返神经。间歇性监测评估刺激时的神经功能，而连续监测则检测可能导致术后喉返神经麻痹的神经损伤的早期迹象。当需要进行全甲状腺切除术时，对侧手术信号衰减会怀疑在同一步骤中继续进行对侧手术。
