Laryngeal vocal and endoscopic alterations after thyroidectomy under local anesthesia and hypnosedation.
Vocal alterations after thyroidectomy are generally related to laryngeal nerve injury or laryngotracheal mobility disorders caused by postoperative fibrosis or strap muscle lesion.


OBJECTIVE
this study aims to evaluate the frequency of vocal and rima glottidis disorders after thyroidectomy.


METHODS
This is a prospective study based on 35 patients submitted to thyroidectomy under local anesthesia and hypnosedation. All patients underwent voice auditory perception evaluation, voice acoustic tests and videolaryngostroboscopy preoperatively, and at one week and at 30 days postoperatively. Bilateral cricothyroid muscle electromyography was performed on the thirtieth day after surgery to confirm the presence of injury in the external branch of the superior laryngeal nerve.


RESULTS
14.3% of the patients presented posterior glottis deviation before surgery and normal electromyography findings. Transient and permanent vocal alteration occurred in 25.7% and 14.2% of the patients respectively.


CONCLUSIONS
voice disorders evaluated after voice auditory perceptive evaluation and voice acoustic tests were more intense in the group with superior laryngeal nerve external branch injury than in the injury-free dysphonic patient group. Oblique glottis can be present in normal patients; however its onset after thyroidectomy is indicative of superior laryngeal nerve external branch lesion.
ENT Department, Medical School, Campinas State University, Campinas, SP, Brazil.
Lincoln Santos
LS
Souza
Agrício Nubiato
AN
Crespo
Jovany Luís Alves de
JL
Medeiros
D000328:Adult; D000368:Aged; D000772:Anesthesia, Local; D055154:Dysphonia / Q000175:diagnosis / Q000209:etiology*; D004576:Electromyography; D005260:Female; D006801:Humans; D006991:Hypnosis, Anesthetic; D061224:Laryngeal Nerve Injuries; D007828:Laryngoscopy; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012720:Severity of Illness Index; D013965:Thyroidectomy / Q000009:adverse effects* / Q000379:methods; D055815:Young Adult