A new experimental approach to assessment of velopharyngeal adequacy: nasal manometric bleed testing

A new experimental method for assessment of velopharyngeal adequacy/inadequacy, using nasal manometric pressure readings for three types of speech conditions under controlled incremental bleed conditions, is described. Cleft palate speakers (N = 30) tended to have higher nasal pressure readings than non-flect palate speakers (N = 56), with or without bleed conditions. Reduction in nasal pressure under controlled incremental bleed for non-cleft palate speakers and cleft palate adequate (CPA) speakers is compatible with an aerodynamic quadratic equation. Unlike cleft palate inadequate (CPI) speakers, non-cleft palate speakers and CPA speakers exhibit similar ability to achieve 0 cm nasal monometric pressure under a bleed bore diameter of 4 mm for a circular bleed orifice. Results for cleft palate marginal (CPM) speakers are less conclusive. Reliability of nasal manometric bleed testing was limitedly tested but not conclusively established in the present report. Further study of reliability and validity is necessary.