The Correlation of GRBAS Scales and Laryngeal Stroboscopic Findings for the Assessment of Voice Therapy Outcome in the Patients with Vocal Nodules

Yun, Young Sun; Lee, Eun Kyung; Baek, Chung Hwan; Son, Young Ik

Abstract

BACKGROUND AND OBJECTIVES
The size of nodule is generally known as a main criterion for the evaluation of voice improvement in the patients with vocal nodules. However, the patients who are receiving voice therapy for their vocal nodules frequently report variable degree of improvement in their voice quality even though the size of nodules remain unchanged during the stroboscopic evaluation. We aimed to define valuable parameters of laryngeal stroboscopy in evaluating the efficacy of voice therapy for vocal nodules. SUBJECTS AND METHOD: We reviewed the medical records of twenty adult women with bilateral vocal nodules. They received 4 to 8 sessions of voice therapy and reported variable degree of their voice improvement. Laryngeal stroboscopy (nodule size, glottal closure, vocal fold vibration, laryngeal tension), acoustic analysis (jitter, shimmer), perceptual parameters (GRBAS) were evaluated before and after voice therapy. Laryngeal stroboscopic gradings and GRBAS gradings were matched and analyzed for their correlation. RESULTS: There were significant correlations between R and vocal fold vibration; between B and nodule size and glottal closure; between S and laryngeal tension; between G and glottal closure, vocal fold vibration and laryngeal tension. CONCLUSION: Among laryngeal stroboscopic findings, improved glottal closure, vocal fold vibration and decreased laryngeal tension as well as decreased nodule size are proved to be useful parameters to evaluate the effectiveness of voice therapy in the patients with vocal nodules.