Acoustic Analysis of Benign Vocal Cord Lesions: Before and after Microlaryngeal Surgery

Nam, Soon Yuhl; Park, Jeong Hyeog; Jeon, Hyung Gyung; Kim, Sang Yoon

Abstract

BACKGROUND AND OBJECTIVES: Benign vocal cord lesions that are not responsive to medical and/or speech therapy are often treated by microlaryngeal surgery. The purpose of this study is to measure selected acoustic parameters to document quantitative changes in vocal quality before and after microlaryngeal surgery and to analyze differences of prognosis for various benign vocal cord lesions, such as vocal cord polyp, vocal cord nodule, and Reinke's edema.
MATERIALS AND METHODS
The authors used a computerized acoustic analysis program (CSL-MDVP) to measure mean fundamental frequency (Fo), jitter, shimmer, and noise to harmonics ratio (NHR) from voice samples of selected patients who had benign vocal cord lesions before and after at least 10 weeks of surgery.
RESULTS
The values of Fo and NHR showed no significant difference in all three groups. There was significant improvement in nodule regarding jitter. Also, there was significant improvement in the vocal cord polyp regarding jitter and shimmer.
CONCLUSION
Jitter and shimmer will be effective acoustic parameters in documenting the quantitative changes in vocal quality before and after microlaryngeal surgery.