[Study of voice changes pre- and post-tonsillectomy].

OBJECTIVE

To evaluate changes in acoustic features of voice after tonsillectomy.

METHOD: Thirty-three patients presenting for tonsillectomy were recruited. Voice recordings obtained from patients before and 1 month after surgery, were analyzed using the Kay Elemetrics, multi-dimensional voice processing software. The following parameters were estimated: the first formant (F1, B1), average of fundamental frequency (F0), Jitter percent (Jitter), Shimmer, noise-to-harmonics ratio (NHR).

RESULT: There were significant difference in the first formant frequency and bandwidth before and 1 month after surgery. The larger the tonsil was, the more changes were seen in the formant frequency. No significant differences were found for F0, Jitter, Shimmer, NHR decreased after the surgery.

CONCLUSION

The modifications in the anatomical structure and volume of the vocal tract, induced by the tonsillectomy can change the formant frequency and bandwidth. The larger the tonsil was, the more changes were detected in the formant frequency.