VOICE AND HEALING AFTER VOCAL FOLD EPITHELIUM REMOVAL BY CO2-LASER VSMICROLARYNGEAL STRIPPING

Controversy exists regarding voice recovery after the use of laser vs. microforceps techniques in the removal of benign vocal fold lesions. The purpose of this study is to compare recovery of voice and healing between groups of cats undergoing vocal fold epithelium removal by CO2 laser and those having vocal fold stripping. Fourteen adult female ca ts underwent standardized unilateral vocal fold injuries by CO2 laser ablation or stripping. After a 6-week recovery period, phonations were evoked by electrical stimulation of the midbrain periaqueductal gray area. Phonations were recorded for acoustic analysis. The larynges wer e harvested, fixed, and sectioned for histologic correlation. Acoustic analysis showed the mean signal-to-noise ratios in the laser group (1 9.72) to be significantly higher than those in the stripped group (13. 51) (p = 0.04). The stripped group showed significantly greater amplit ude perturbation (8.68% vs. 2.43%, p = 0.02). No between-group differe nce was found for period perturbation. Histologically, the laser group showed minimal Reinke's space scarring and near-normal epithelial reg eneration, and the stripped group showed marked subepithelial scarring , often involving the vocalis muscle. These results demonstrate superi or recovery of voice and healing in animals undergoing vocal fold epit helium removal with the CO2 laser. Inferior outcomes seen in the strip ped group may be related to difficulty in preserving Reinke's space du ring epithelium removal.