Variations in velopharyngeal structure and function in adults with normal and cleft anatomy.

Abstract

Examination of velopharyngeal (VP) muscle differences among adults with cleft palate is limited. Dynamic assessment of the VP muscles have predominantly been during rest or sustained phonation. The purpose of this study is to examine differences in VP structure and function between adults with repaired cleft palate and adults with normal anatomy at rest and during speech production. Twelve adult participants (six with normal anatomy, six with repaired cleft palate) completed a 3D static and dynamic MRI protocol. Static image analyses of 12 participants included measures of cranial, velopharyngeal, and levator morphology. Dynamic MRI was obtained in the sagittal and oblique coronal planes during dynamic speech production of "ampa" for 8 participants. Differences between groups were analyzed using independent sample t-tests ([alpha] < 0.05). Significant differences between study groups were noted for static measures of posterior cranial base angle, palate length, palate height, pharyngeal depth, and VP ratio. During speech production, significant differences were observed between adults with repaired cleft palate and those with normal anatomy on angular measures of velar height and velar bending during production of selected phonemes within the speech task. High variability within groups and the limited sample size may have impacted statistical findings. Continued advancements in MRI technology will provide insight into differences in VP function between normal and cleft anatomy and may contribute to a better understanding of the effects of surgical palate repair on physiology for speech production.