Cepstral Analysis of Voice in Children With Velopharyngeal Insufficiency After Cleft Palate Surgery

Objectives. The purpose of this study is to survey the cepstral peak prominence (CPP) of vowel sounds and to compare objective data obtained from patients with velopharyngeal insufficiency after cleft palate surgery with objective data of those with normal healthy controls using acoustic analyzer. Methods. Participants were divided into a clinical group and a control group. Every participant was recorded phonating the sustained vowel /a/. Each participant in the clinical group was recorded before surgery, before and after speech therapy. All samples were subjected to acoustic analysis using Praat software. The vowels were analyzed acoustically by the measurement of smoothed cepstral peak prominence (CPPs). Results. The results reveal lower values of CPPs in speakers with velopharyngeal insufficiency before and after the operation. And, the results also reveal that there is no significant difference across the control and the clinical groups after speech therapy. Conclusions. The results reveal lower values of CPPs in the clinical group before surgery and before speech therapy in comparison with the control group, which could be explained because of the body's compensation for the lack of normal intraoral pressure and habit of articulation.