Effects on voice by endolaryngeal microsurgery.

Endolaryngeal microsurgery (EM) is functionally oriented. Therefore, assessment of vocal function is important to evaluate the effect of the surgery on voice. In all, 58 patients, including 26 patients with vocal cord nodules and 32 patients with vocal cord polyps, underwent EM. The patients' voices were recorded and analyzed before EM and 2 weeks after. Analysis of voice quality included perceptual assessment and each patient's own subjective evaluation of social acceptability of voice according to the 10.0 cm visual analogue scale (VAS) scale. Acoustic voice signal data were measured for fundamental frequency (Fo), jitter, shimmer and normalized noise energy (NNE) using Tiger Electronics Dr. Speech software. Statistically significant (P < 0.001) improvement was achieved in both perceptual and acoustic analysis and in both patient groups. According to the VAS scale, a high degree of satisfaction with the surgery was achieved. The grade of hoarseness (G) as well as roughness (R) and breathiness (B) decreased significantly after the operation. EM resulted in a statistically significant decrease in the mean jitter, shimmer and NNE postoperatively. There were no significant changes in the Fo after EM. These results confirm a high degree of effectiveness of EM on vocal rehabilitation and meet the expectations regarding the assessment and documentation of postsurgical voice changes.