title: Identification of the external branch of the superior laryngeal nerve during thyroidectomy.
abstract: Seventy-six patients underwent preoperative vocal evaluation and were randomized into 3 groups: (1) those with the superior thyroid pole dissected by the first author, with the external branch of the superior laryngeal nerve (EBSLN) identified by means of a nerve stimulator; (2) those patients whose dissection was executed by a resident, with no nerve search; and (3) those whose dissection was undertaken by the first author, without any nerve search. Postoperative analysis consisted of voice evaluation and electromyography of the cricothyroid muscle. No lesion occurred in patients in group 1. Twenty-eight percent of patients in group 2 and 12% in group 3 experienced a complete lesion of the EBSLN (p = 0.0123). When the patients in group 1 were compared with the patients with 62 nerves corresponding to nonoperated thyroid lobes, patients in group 1 exhibited no increased risk, whereas a significantly increased hazard was evident in both groups 2 (p = 0.0002776) and 3 (p = 0.0346393). In this study, effective prevention of iatrogenic EBSLN lesions during thyroidectomies was achieved only by the intraoperative identification of the nerve with the nerve stimulator.
authors.affiliation: University of Sao Paulo Medical School, Brazil.
authors.forename: C R
authors.initials: CR
authors.lastname: Cernea
authors.forename: A R
authors.initials: AR
authors.lastname: Ferraz
authors.forename: J
authors.initials: J
authors.lastname: Furlani
authors.forename: S
authors.initials: S
authors.lastname: Monteiro
authors.forename: S
authors.initials: S
authors.lastname: Nishio
authors.forename: F C
authors.initials: FC
authors.lastname: Hojaij
authors.forename: A
authors.initials: A
authors.lastname: Dutra Júnior
authors.forename: L A
authors.initials: LA
authors.lastname: Marques
authors.forename: P A
authors.initials: PA
authors.lastname: Pontes
authors.forename: R G
authors.initials: RG
authors.lastname: Bevilacqua
mesh_terms: D000328:Adult; D004558:Electric Stimulation; D004576:Electromyography; D005260:Female; D006801:Humans; D007430:Intraoperative Care; D007431:Intraoperative Complications / Q000517:prevention & control*; D061224:Laryngeal Nerve Injuries; D007823:Laryngeal Nerves / Q000033:anatomy & histology / Q000502:physiology; D008297:Male; D010699:Phonation; D011182:Postoperative Care; D011300:Preoperative Care; D011446:Prospective Studies; D015203:Reproducibility of Results; D013965:Thyroidectomy; D013997:Time Factors