Application of external branch of superior laryngeal nerve monitoring in thyroid surgery of tumor in upper pole / 中华内分泌外科杂志

Objective To explore the value of monitoring techniques of the external branch of superior laryngeal nerve (EBSLN) in thyroid surgery and to study its protective effects on vocal function after thyroid surgery.Methods We retrospectively analyzed the clinical data of 139 patients who underwent primary surgery of papillary thyroid cancer with neurological monitoring from Jun.2017 to Mar.2018 in the General Surgery Department of PLA General Hospital.The tumors of 31 cases were located in the upper pole of the gland and elsewhere in 108 cases.The patients' vocal function was assessed at one week and one month after surgery.The rate of EBSLN identified visually and by the intraoperative nerve monitoring (IONM) were counted.EBSLN recognition efficiency and prevalence of EBSLN damage during the operation of tumor in upper pole of thyroid and in other location were compared.Results In the 139 patients,there were 218 upper poles(218 EBSLN) treated intraoperatively,of which 145 were recognized visually (126(57.8％) confirmed by IONM,and 203(93.1％) were identified by IONM,OR=8.27(x2=59.345,P=0.00).The percentage of EBLSN located in the upper pole accurately identified by the naked eye was 20/46(43.5％) while by IONM was 43/46(93.4％).The percentage of EBSLN at the other position accurately identified visually was 106/172(61.6％),and by IONM was 160/172(93.0％).The number of visually identified cases in different locations showed significantly differences according to the chi-square test (x2=4.901,P=0.027),and no significant difference by IONM identification according to chi-square test (x2=0.012,P=0.914).Five patients had a low voice at one week postoperatively and low voice and vocalization change were not observed after one month.Conclusions IONM can effectively increase the proportion of intraoperative EBSLN identification to ensure the safety of surgery.The difficulty of visual identification of EBSLN during the surgery of tumor in upper pole is greater than that in other locations.IONM can provide more evidences for nerve protection and reduce the risk of injury.

A review of application of intraoperative external branch of superior laryngeal nerve monitoring in thyroid surgery / 中华内分泌外科杂志

Laryngeal nerves injury,including recurrent laryngeal nerve (RLN) and superior laryngeal nerve,is one of the most terrible complications of thyroid surgery.External branch of superior laryngeal nerve (EBSLN) is adjacent to the upper pole of thyroid gland,which make it vulnerable to be injured during the ligation of the superior thyroid vessels.As a result,patients would have phonating dysfunction,especially the changes in the voice quality alongside the alterations in the high pitched sound production ability.Intraoperative neural monitoring technique applying neural electrophysiology method to detect and protect the nerve and assess its function during the operation decreases the occurrence of EBSLN injury and improves the living quality.This article is going to make a review of the progress of the application.

Application of intraoperative neuromonitoring technology in protection of external branch of superior laryngeal nerve / 中华内分泌外科杂志

Objective To investigate the application of intraoperative neuromonitoring (IONM) during thyroidectomy for external branch of superior laryngeal nerve(EBSLN).Methods From Jan.2017 to Jun.2017,138 patients undergoing thyroidectomy were randomly divided into monitor group (n=69) and the control group (n=69).The monitor group were used IONM for EBSLN,while the control group were used conventional area protection.Results The overall incidence of EBSLN injury was 1.4％(1/69) in the monitor group,and the overall incidence of EBSLN injury was 11.6％(8/69) in the control group.There was statistical significance between the two groups.Conclusion The application of IONM in thyroidectomy can exactly identify EBSLN,and reduce the possibility of EBSLN injury remarkably.

Protection of the external branch of the superior laryngeal nerve in carotid endarterectomy / 中国脑血管病杂志

Objectives To investigate the methods of protecting external branch of the superior laryngeal nerve (EBSLN)in carotid endarterectomy and to observe the effect of using these methods in clinical surgery. Methods EBSLN (20 sides)of 10 heads of corpse were studied by using microanatomy from January 2013 to December 2013. The occurrence probability of EBSLN on the lower edge of posterior belly of digastric muscle,medial edge of external carotid artery and upper edge of superior thyroid artery in anatomy triangle was analyzed. The distances from the midpoint of the EBSLN to carotid bifurcation, mandibular angle and mastoid tip were measured. Sixty-five patients with carotid endarterectomy in Tianjin Huanhu Hospital from December 2013 to November 2014 were treated with the protective methods of the relevant EBSLN by using anatomy triangle as a mark. Whether the patients had injury symptoms of EBSLN were followed up after procedure. Results (1)The occurrence probability of 20-side EBSLN in anatomy triangle was 95%(19 sides). The midpoint of EBSLN in the anatomy triangle at the posterior mandibular angle was median 0. 34 (-1. 62 to 2. 43)cm,at the inferior mandibular angle was 1. 28 (-1. 33 to 3. 42) cm,at anterior mastoid tip was 2. 84 (0. 51 to 5. 14)cm,at inferior was 4. 51 (2. 82 to 6. 39)cm,and at anterior superior of the carotid bifurcation was 1. 64 (0. 57 to 3. 78)cm. (2)65 patients who underwent carotid endarterectomy used the protective methods of intraoperative EBSLN. There was no manifestation of EBSLN injury at 3 weeks to 9 months after procedure. Conclusion In carotid endarterectomy,taking an anatomic triangle as a symbol,it is no more than 2 cm of the anterior superior of carotid bifurcation during the separation process. As for the patients with higher or lower position of carotid bifurcation,in the range of crossing rear mandibular angle 0. 50 cm or below the mastoid tip 4. 50 cm for arterial separation should be avoided,and this can effectively protect EBSLN.

How to Preserve Laryngeal Nerve for Preventing Post-Thyroidectomy Voice Change / 대한갑상선학회지

After thyroid surgery, voice change occurs very frequently, in more than 30% of cases. In addition to injury to the recurrent laryngeal nerve (RLN) or the external branch of superior laryngeal nerve (EBSLN), vocal fold edema due to excessive tracheal traction or disrupted laryngeal venous drainage, and laryngotracheal fixation following injury to extralaryngeal musculature can cause post-thyroidectomy voice change. Although complete recovery can be expected mostly in 3 months, dysphonic patients should be evaluated pre and postoperatively by laryngoscopy or laryngeal stroboscopy. The present review discusses the evaluation of voice change, the anatomy of RLN and EBSLN and common cause of voice change after thyroid surgery. Furthermore, we represent how to preserve RLN, SLN including intraoperative nerve monitoring.