Comparison of Vocal Outcome after Autologous Fat Injection and Medialization Thyroplasty for Unilateral Vocal Cord Paralysis

Bae, Sung Hyen; Lee, Sang Joon

Abstract

BACKGROUND AND OBJECTIVES
Glottic incompetence from the unilateral vocal cord paralysis can be improved by medialization of the paralyzed vocal cord. There are many medialization techniques. Among them, medialization thyroplasty and injection laryngoplasty are frequently used techniques. We compared the vocal outcomes of fat injection and medialization thyroplasty in unilateral vocal cord paralysis. The aim of this study is to find out which modalities are more preferable as initial treatment of unilateral vocal cord paralysis. MATERIALS AND METHOD: From 2004 January to 2008 September, medialization thyroplasty was performed in 13 patients and fat injection in 14 patients for unilateral vocal cord paralysis. We analyzed the voice quality by several subjective and objective parameters. The parameters are visual analog scale, GRBAS scale, acoustic analysis (fundamental frequency, jitter, shimmer, noise to harmonic ratio), and aerodynamic analysis (maximum phonation time, mean flow rate, subglottic pressure).
RESULTS
Visual analog scale, jitter, shimmer and maximum phonation time are improved after both medialization thyroplsty and fat injection. In GRBAS scale, fat injection showed statistically significant improvement compared with medialization thyroplasty. The mean flow rate was also significantly decreased in fat injection.
CONCLUSION
Both medialization thyroplasty and fat injection improved voice quality. But injection laryngoplasty with fat may be superior to silastic medialization in short-term voice outcome.