The relationship between soft phonation index (SPI) and muscle tension dysphonia type 1 and effects of voice therapy

ABSTRACT Master of Science Thesis THE RELATIONSHIP BETWEEN SOFT PHONATION INDEX (SPI) AND MUSCLE TENSION DYSPHONIA TYPE 1 AND EFECTS OF VOICE THERAPY SERKAN BENGİSU Anadolu University Institute of Medical Sciences Department of Speech and Language Therapy Supervisor: Seyhun TOPBAŞ, Assc. Prof, phD 2004 This study aims to assess and describe the relationship between soft phonation index (SPI) and muscle tension dysphonia type 1 and its usefulness in determining the effects of voice therapy. The study is based on an experimental study and is composed a search for two phases. In the first phase, acoustic parameters beyound the normal limits were determined and any correlation between SPI and the muscle tension dysphonia (MTD) type 1 was conducted. The second phase was conducted to evaluate the effects of voice therapy in the analysed samples addressing the use of these parameters as a follow- up as well as a severity criteria. Twenty subjects with MTD type 1 and the same number of subjects with similar demographic data as a control group having no voice problems were included in the study. Dynamic microphone (Shure Dynamic cardioid microphone SM48), sound blaster live card, Pentium IH 650 mHz computer were used to record and analysed. Acoustic analysis was performed by using MDVP (Multi-Dimensional Voice Program, Model 5105, Version 2.3) software before and after therapy and the results were compared by using student -tests. The acoustic results showed that several parameters were effected in MTD typel patients. The most deviant parameter was found to be SPI (95%), whereas the second most common impairment was vAm(55%) Cases were also observed to have abnormalities in vFo, jitter, PPQ (45%), sPPQ (30%), jitta (20%), shimmer, ShdB, ATRI (20%), APqQ sAPQ (10%) levels. Voice outcomes were compared to evaluate the effects of the voice therapy. Statistically the most significant change was observed in SPL Additionally fundamental frequency (fo), amplitude variation (vAm), jitter (%), shimmer (%), pitch perturbation quotient (PPQ), amplitude perturbation quotient (APQ). These parameters statistically revealed significant changes before and after six sessions of voice therapy (p<0,05). The only parameter showing no significant change was the harmonic to noise ratio (HNR). It can be concluded that SPI seems to be highly correlated with the functional dysphonia MTD type 1 disorder. As the therapeutic approach proceeded, the parameters including the amplitude and frequency perturbations also showed a significant improvement Therefore these parameters, especially the SPI, can be used for detecting the severity and/or the success of the treatment modalities in MTD type 1 patients. Keywords: Voice Disorders, Functional Dysphonia, Muscle Tension Dysphonia, Acoustic Analysis, Voice Therapy