Multidimensional acoustic analysis of pathological voice
Introduction. There are subjective and objective ways to examine the effects of vocal therapy in voice disorders. The most precise and objective check-up is the use of computer voice analysis. Objective. The aim of the research was to perform a detailed analysis of acoustic structure of the vowel A before and after voice treatment in patients with vocal fold nodules in order to obtain objective verification of the vocal rehabilitation success. Methods. We examined 30 female patients, aged 34.6?6.69 years, with vocal fold nodules. Acoustic parameters of voice were compared with the control group consisting of 21 subjects without voice pathology. In all persons the vowel A was recorded and analyzed before and after a month of vocal therapy. The success of the vocal therapy was tracked using computer analysis of vocal structure. Signal, noise and tremor parameters were processed. Results. Of the analyzed vowel A parameters: STD, PER, JITA, JITT, RAP, vFO, ShdB, SHIM, APQ, VTI, SPI, F0, NHR, FTRI, eleven improved (p<0.05 and p<0.01). Three parameters (F0, NHR, FTRI) changed showing improvement, but the obtained differences were not statistically significant (p>0.05). Conclusion. Based on the obtained results it was concluded that vocal therapy gave satisfactory results, but that it should be continually applied until full stabilization of the voice.