A voice acoustic analysis of thyroid adenoma patients after a unilateral thyroid lobectomy

The objective of this study was to investigate the features of voice changes in thyroid adenoma patients secondary to a unilateral thyroid lobectomy that did not result in laryngeal nerve injury.

Prospective study.

Pre- and postoperative fiberlaryngoscopic and voice acoustic analyses were performed on 32 adult patients (eight males and 24 females) with unilateral thyroid adenoma. Forty adults (20 women and 20 men) with normal voice function were grouped as controls.

The vocal folds before and after surgery in all patients appeared to be normal under the fiberlaryngoscope. The preoperative voice was slightly abnormal in female patients and normal in male patients. One week after surgery, the F0 levels of both male and female patients decreased significantly from the values recorded before surgery (P<0.05). One month after the surgery, the F0 standard deviation, fundamental frequency perturbation, amplitude perturbation, noise/harmonic ratio, voice turbulence index, and degree of subharmonics in female patients decreased significantly from the values observed before surgery (P<0.05). Three months after surgery, the values of these indicators returned to normal.

The preoperative voice was slightly abnormal in female patients and normal in male patients. After a unilateral thyroid lobectomy, which did not result in injury of the laryngeal nerve, the acoustic measures of male patients consequently became slightly abnormal and returned to normal within 1 month. The indicators of female patients improved from that demonstrated before surgery and returned to normal within 3 months.