It has been reported that up to 87% of patients have a degree of voice dysfunction after thyroidectomy, even when the laryngeal nerves are preserved. Postoperative inflammation, laryngeal oedema due to vascular congestion, direct damage to the cricothyroid muscles and intubation-related trauma have all been postulated as possible mechanisms for this observation. Most voice disturbances are reported to resolve by 3-6 months postoperatively. This prospective study of 191 patients undergoing a total thyroidectomy with preservation of the laryngeal nerves and no vocal cord palsy after surgery assessed subjective and objective voice outcomes at one and eight weeks postoperatively. These were compared to preoperative assessments as well as a control group of patients undergoing lateral neck or non-neck surgery.
Subjective and objective dysphonia was noted in the study population in the immediate period (one week postoperatively) after total thyroidectomy. This was not observed in the control group, suggesting that intubation trauma was not the primary explanation for the observed dysphonia.
When the study population was divided into younger (less than 40) and older patients (greater than 40), it was observed that all subjective and objective voice dysfunction had resolved by eight weeks postoperatively in the younger cohort, whereas older patients continued to exhibit acoustic and aerodynamic changes by the eighth week. Even in the older cohort however, voice handicap index (VHI) values had returned to preoperative levels by eight weeks. Whilst this paper serves mainly to confirm previous observations regarding voice outcomes after total thyroidectomy, it does suggest that any dysphonia with intact laryngeal nerves will be temporary in the majority of cases and should resolve as soon as eight weeks postoperatively. Voice dysfunction may be more prolonged in older patients, but only on objective assessments and not to a degree significant enough to be noticed by patients themselves.
