Structural and functional causes of hypernasality in velocardiofacial syndrome. A pilot study.

OBJECTIVE Hypernasality in velocardiofacial syndrome (VCFS) is more severe, persistent, and difficult to manage compared to other populations with cleft palate or velopharyngeal (VP) dysfunction. This pilot study investigated why children with VCFS have more severe hypernasality. METHODS Pressure-flow methodology indirectly measured VP orifice size and VP closure timing during speech in a group of 5 children with VCFS, 5 children with cleft palate, and 6 normal children. RESULTS Children with VCFS demonstrated significant differences in VP closure timing and hypernasality. There were no significant group differences in VP orifice size. Duration of nasal airflow was the strongest predictor of judgments of hypernasality. CONCLUSION This study provides preliminary evidence that VP closure timing may account for the more severe hypernasality in children with VCFS, compared to structural factors alone.