Acoustic Analysis of Voice in Laryngopharyngeal Cancers Pre and Post Radiotherapy

Laryngopharyngeal cancers are one of the most commonly diagnosed head and neck malignancies frequently presenting primarily with change in voice. Radiotherapy being the main modality of treatment for early cancers continues to affect voice. Hence, acoustic analysis of the voice offers quantifiable values of several parameters delineating the obvious effect of the therapy. A total number of 60 patients, diagnosed with laryngopharyngeal cancers undergoing radiotherapy underwent acoustic voice assessment using Dr. speech software pre-treatment and at 1 and 3 months post radiotherapy. Data analysis was done using Mann-Whitney test and Wilcoxon signed rank test and a significant p value was obtained. The results of the study showed fundamental frequency (F0) and noise to harmonic ratio (NHR) to be the most affected in comparison to Jitter and Shimmer. The F0 and NHR values across baseline evaluation, first month and third month follow up showed a steady deterioration which was significant. The deterioration noted from the first to third month was not statistically significant. Across genders both F0 and NHR deterioration is more in males than in females. Radiotherapy causes definitive alterations in some acoustic measures of voice, which make the voice disharmonic and hoarse with contribution of harshness and breathiness. The effect is more pronounced on vocal parameters that are structure and projection based as evidenced by deterioration in values noted in F0 and NHR. Persistent deteriorated acoustic parameters for a longer duration of time are more likely which emphasizes the need for early voice rehabilitation.