Thyroid surgery and voice-related outcomes

Background: Vocal dysfunction in patients with thyroid pathology has been poorly documented, and dysfunction after thyroid surgery is generally reported in terms of recurrent laryngeal nerve or external laryngeal nerve palsy. But voice dysfunction is more complex than simply nerve integrity. The present study reports the incidence of dysphonia in patients presenting for thyroid surgery, and relates postoperative changes in vocal function to recurrent and external laryngeal nerve function, and the surgical handling of the strap muscles. Methods: Fifty patients were assessed by Visipitch before and after thyroidectomy. Following surgery the patients filled out a questionnaire. Results: Overall 26 of 44 patients had no subjective postoperative voice change, while 10 reported subjective deterioration and eight reported subjective improvement in voicing. Postoperative objective assessment of these patients found that 17 were the same, eight refused to come for testing because they felt their voice had not changed, 13 were better and six were worse. Following surgery two patients (4.5%) had temporary recurrent laryngeal nerve palsies (2.5% of nerves at risk), and four patients (10%) suffered external laryngeal nerve palsies. Division of strap muscles was not detrimental to voicing. Six patients were lost to follow-up. Fifteen patients (34%) presented with vocal abnormalities, six (40%) of whom improved postoperatively. Conclusions: Patients may have voicing abnormalities before thyroid surgery is performed. Surgery may improve or worsen the voice irrespective of the pre-operative voice status.