Higher prevalence of voice disorders in patients with cleft lip and palate? results from two studies

This paper addresses two questions about voice disorders in patients with cleft lip and palate (CLP): 1. What is the actual prevalence of voice disorders in CLP and is this prevalence higher than in the non-cleft population? 2. Is there an interaction between hypernasality and phonatory dysfunction which can be assessed in terms of signal perturbation quotients? In the first study, 154 CLP patients were examined perceptually and with the MODIAS software. Severe voice disorders were found in 6.5% of the CLP group which is numerically only slightly higher than in the normal population. None of the pertubation quotients differentiated between modal and disordered voices. In the second study, 22 hypernasal and 20 nonhypernasal CLP patients were compared to 14 tumor patients using the EZVoice software. The perturbation measures differentiated dysphonic patients from patients with normal voices. An effect ofhypernasality on the signal perturbation could not be verified.