OBJECTIVE: The purpose of this study was to analyze the acoustic characteristics associated with alternation deformation of the vocal tract due to large epiglottic cyst, and to confirm the relation between the anatomical change and resonant function of the vocal tract.
METHODS: Eight men with epiglottic cyst were enrolled in this study. The jitter, shimmer, noise-to-harmonic ratio, and first two formants were analyzed in vowels /a:/, /e:/, /i:/, /o:/, and /u:/. These values were analyzed before and after laryngeal microsurgery.
RESULTS: The F1 value of /a:/ was significantly raised after surgery. Significant differences of formant frequencies in other vowels, jitter, shimmer, and noise-to-harmonic ratio were not presented.
CONCLUSION: The results of this study could be used to analyze changes in the resonance of vocal tracts due to the epiglottic cysts.