RESUMEN
BACKGROUND AND OBJECTIVES: This study was carried out to analyze voice changes after curative radiotherapy in T1 glottic cancer and the clinical efficacy of electroglottography (EGG) as a new treatment method for voice analysis. MATERIALS AND METHOD: From February 2002 to December 2004, 10 patients with T1 glottic squamous cell carcinoma who underwent a curative radiotherapy were studied prospectively. They received voice quality measurement (Perceptual evaluation, Acoustic analysis) and vocal function test (Aerodynamic study, Videostroboscopy, EGG) one year before and after radiotherapy. RESULTS: Perceptual test showed voice quality improvement after radiotherapy, but 3 cases had still abnormal voices. Acoustic analysis showed that although fundamental frequency, jitter and shimmer changed significantly after radiotherapy, HNR did not change and aerodynamic study had no changes after radiotherapy.On the other hand, in the videostroboscopy, glottic closure, wave and non-vibrating portion had significant changes after radiotherapy. In EGG, %Fx and Qx also showed significant changes whereas %Ax had no changes. CONCLUSION: This study suggests that the voice improves significantly after radiotherapy and multi-dimensional analysis with diverse method is required in voice analysis. In addition, EGG may be used as a reliable method in vocal function test.