Effects of Tonsillectomy on Articulation

Abstract

Changes in the articulation of 5 Japanese vowels after tonsillectomy were investigated using for-mants as indicators. Data from 40 patients were analyzed and those from 10 healthy volunteers were used as control. The comparison of formant frequencies before surgery and those 1 month after surgery revealed that Fl, F2 and F4 remained within the range of intra-individual fluctuations in many cases. F3, however, exceedingly decreased in many cases, and the decrease was particularly marked for lol. No evident change was observed as to the formant bandwidth. The larger the tonsill, the greater the changes in formant frequency. Using Mackenzie's classification, evaluations were unsatisfactory. Observing the postoperative changes over time, it was suggested that the altered vocal tract compensated slowly using surrounding tissues. From the acoustic evaluation, the changes in articulation due to surgery were considered negligible in clinical practice, although the problem for professional vocalists cannot be disregarded. © 1995, The Society of Practical Otolaryngology. All rights reserved.