Perceptual evaluation of the effect of external radiotherapy in the neck area on changes of voice and the voice quality of Czech patients

This research is focused on changes of voice and the voice quality before radiotherapy treatment and in time of one year after external radiotherapy (RT) in the neck area of Czech patients and to compare measurement for different subgroups of patients (by age, gender, surgical resection, aphonia, etc.). The perceptual test was performed on 16 patients undergoing external radiotherapy in the neck area and the changes of voice and the voice quality compared at before RT and 1, 6 and 12 months after RT. 2 clinicians and 1 trained voice specialist evaluated GIRBAS parameters of the voice quality and 96 lay listeners evaluated the scope of change of voice. The results of perceptual tests of lay listeners point to the difference of change in voice is the most pronounced in patients who had aphonia during the RT. Of the GIRBAS parameters, instability and roughness changed the most after RT treatment.