Perceptual and acoustic voice analysis in patients with glottis cancer after endoscopic laser cordectomy

Introduction: Treatment of glottis cancer, despite oncological safety, should consider postoperative voice quality. CO2 laser endoscopic cordectomy allows radical removal of the tumor while maintaining respiratory, defensive and phonatory functions. The aim: The aim of the study is perceptual and acoustic evaluation of voice in patients after endoscopic CO2 III–Va laser cordectomy due to glottis cancer. Material and method: The study included 30 men after CO2 cordectomy. 13 (43%) patients underwent type III cordectomy, 6 (20%) – type IV; 11 (37%) – type Va. Voice quality has been assessed 6 months after the surgery. Control group included 30 healthy men of the same age. GRBAS scale has been used in perceptual evaluation of voice. Acoustic analysis has been performed using DiagnoScope Specjalista software. Narrowband spectrography and Maximum Phonation Time (MPT) measure has been performed. Results: In study group, voice has been classified as G1R1B0A0S0 after type III cordectomy; as G1R1B1A1S2 in type IV and as G2R1B1A0S3 in type Va. Acoustic evaluation revealed the highest values of F0, Jitter, Shimmer and NHR after Va cordectomy as well as non-harmonic components in narrowband spectrography and reduction of MPT. Conclusions: Postoperative voice quality depends on the type of cordectomy. Perceptual assessment indicates that type IV and Va cordectomy cause intensification of voice disorders. Parameters of acoustic evaluation increase with the extent of the procedure. The presence of non-harmonic components in narrowband spectrography increases with the extent of cordectomy, such as the reduction of MPT. Preservation of anterior commissure influences good voice quality in perceptual and acoustic assessment.