The purpose of this study was to determine the postoperative pitch range acquired in cases of unilateral vocal fold paralysis, as well as factors affecting outcomes.
We analyzed 39 cases of unilateral vocal fold paralysis for which surgery was performed between January 2006 and January 2009 and for which pitch ranges and the items listed below were measured preoperatively and 1 year postoperatively. Arytenoid adduction (AA) and type I thyroplasty were performed simultaneously in all cases regardless of preoperative severity. AA was performed by the fenestration approach as previously reported. In this procedure, the cricoarytenoid and cricothyroid joints are not released. Correlations between pitch range acquired postoperatively and the following items were examined: (1) pre- and postoperative maximum phonation time (MPT), (2) pre- and postoperative mean airflow rate (MFR), and (3) preoperative pitch range. Furthermore, patients were surveyed regarding their ability to sing after surgery, and the pitch range cutoff value dividing ability and inability to sing was calculated.
Pitch range increased significantly from 3±4.47 halftones (mean ± standard deviation) preoperatively to 17.5±5.80 halftones postoperatively. Preoperative MPT, MFR, and pitch range did not correlate with postoperative pitch range. Postoperatively, only MPT correlated with the width of postoperative pitch range. Twenty-three of 39 subjects (59%) responded that they were able to sing, and the pitch range cutoff value dividing the two groups was 22 halftones.
AA and type I thyroplasty significantly expanded postoperative pitch range. There was no correlation between preoperative severity and width of pitch range acquired postoperatively.