A Respirometric Technique to Evaluate Velopharyngeal Function in Speakers with Cleft Palate, with and without Prostheses

Abstract

There is a paucity of respirometric quotient (RQ) data on individuals with velopharyngeal inadequacy. Paesani (1964) reported data using a technique that involved separate productions of the same task to obtain the RQ. The RQ values obtained were greater than unity, which is theoretically impossible. In the present study, respirometric quotients, the ratio of oral air volume expended to total volume expended, were obtained using separate but simultaneous productions of oral and nasal airflow. RQ values were calculated for 10 speakers with cleft palate, with and without their prosthetic appliances, and 10 normal speakers. As a group, those with cleft palate and without their appliances exhibited RQ values that were significantly lower than values obtained from the normal speakers and from speakers with the appliances in place. These findings indicated that there were no statistically significant differences in RQ values when comparing sentence repetition and counting tasks. These values were lower than those obtained for the nonnasal syllable repetition tasks, with the/m/ syllable repetition task generally being associated with the lowest RQ value of any of the speech tasks. The correlation between RQ values and perceptual judgments was -.60, indicating that there was modest agreement between the two measures. As RQ values decreased, perceptual judgments of nasality increased.