Nasometric discrimination of hypernasality and turbulent nasal airflow.

Agreement between nasalance measures and perception of nasality during speech is not consistently strong. A possible reason may be the complicating combined effects of nasal turbulent airflow and nasal resonance. The purpose of this preliminary study was to examine nasalance measures obtained during production of a low pressure speech sample designed to minimize or eliminate the effects of turbulent nasal airflow. The results showed that nasalance measures obtained as some of the subjects produced the new speech sample were significantly different from those obtained when the standard high pressure speech sample was used. Use of both the new low pressure samples and the standard high pressure samples may result in improved agreement between nasalance measures and ratings of speech nasality as well as assist in the identification of subgroups of patients with marginal velopharyngeal insufficiency.