Aerodynamic indices of velopharyngeal function in childhood apraxia of speech.

Childhood apraxia of speech (CAS) is characterized as a deficit in the motor processes of speech for the volitional control of the articulators, including the velum. One of the many characteristics attributed to children with CAS is intermittent or inconsistent hypernasality. The purpose of this study was to document differences in velopharyngeal function in children diagnosed with CAS from children with typically-developing speech. Pressure-flow techniques were used to estimate the velopharyngeal port size and measure the temporal sequencing of airflow and pressure events associated with production of a nasal + oral plosive sequence in the speech of three children with CAS and three age-matched comparison participants. The results of this pilot study revealed significant differences between the performance of the CAS group and the comparison group in three timing measures of velopharyngeal port closure and velopharyngeal orifice area during speech.