title: The usefulness of preoperative computed tomography and intraoperative neuromonitoring identification of the nonrecurrent inferior laryngeal nerve.
abstract: The objective of this study was to avoid the nonrecurrent inferior laryngeal nerve (NRLN) injury during surgery, we performed preoperative CT examinations to determine the variation in abnormal course of the right subclavian artery as an indictor of the presence of the NRLN and used intraoperative neuromonitoring (IONM) to identify nerve. Preoperative thyroid CT examinations were performed in 783 thyroid surgery patients. The imaging characteristics that suggested the presence of the NRLN were the following: (1) the arteria lusoria arising from the dorsal side of the aortic arch and passing through the trachea and esophagus posteriorly, and the CT image showing the characteristic "hook-like" morphology; (2) that the arteria lusoria imaging could be observed posteriorly to the trachea and esophagus; and (3) that the arteria lusoria traveled transversely from the rear of the right common carotid artery to the right subaxillary region. IONM has been applied to localize and identify NRLN. The brachiocephalic trunk was shown in 779 cases and not in the remaining four cases (0.5 %, 4/783), and these four were assumed to have the arteria lusoria. The separation point and path of the NRLNs were localized and identified precisely with IONM. The NRLN was observed during all surgeries. These four cases did not exhibit hoarseness after surgery. In conclusion, understanding of the course variations of the right subclavian artery using a preoperative CT examination provides an indicator of the presence of a NRLN. Combining these evaluation methods with IONM can avoid NRLN injury.
authors.affiliation: Department of Otolaryngology-Head and Neck, Affiliated Second Hospital, Sun Yat-sen University, 107, Yan Jiang West Road, 510120 Guangzhou, China. caiq163@126.com
authors.forename: Qian
authors.initials: Q
authors.lastname: Cai
authors.forename: Zhong
authors.initials: Z
authors.lastname: Guan
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Huang
authors.forename: Jianpeng
authors.initials: J
authors.lastname: Yuan
authors.forename: Yong
authors.initials: Y
authors.lastname: Pan
authors.forename: Yiqing
authors.initials: Y
authors.lastname: Zheng
authors.forename: Maojin
authors.initials: M
authors.lastname: Liang
authors.forename: Shaochong
authors.initials: S
authors.lastname: Fan
mesh_terms: D002339:Carotid Arteries / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007431:Intraoperative Complications / Q000517:prevention & control*; D064795:Intraoperative Neurophysiological Monitoring / Q000379:methods*; D061224:Laryngeal Nerve Injuries / Q000517:prevention & control*; D007823:Laryngeal Nerves / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D008297:Male; D011300:Preoperative Care / Q000379:methods; D013348:Subclavian Artery / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D013965:Thyroidectomy / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*