Quantitative analysis of the velopharyngeal sphincter function during speech.

OBJECTIVE: This study reports a new concept for quantitative analysis of velopharyngeal function using electromagnetic articulography and simultaneous transoral video endoscopy. PARTICIPANTS: The velopharyngeal closure mechanism was studied in 16 healthy German subjects during production of the vowel-consonant-vowel sequences /afa/ and /apa/. DESIGN: Velar movements in the sagittal and vertical direction were measured by electromagnetic articulography (EMA) while video endoscopy was used for recording in the sagittal and transverse directions. MAIN OUTCOME MEASURE: A transverse sagittal quotient (TSQ) was defined after the measurement of sagittal and transverse diameters of the velopharyngeal port (VPP) in the video-endoscopic pictures on the basis of a frame-by-frame analysis. RESULTS: The sphincter morphology was objectively determined with the TSQ base value. A terminal sphincter deformation (TSD) for closure phases of articulatory movement was revealed by a qualitative shape analysis of the TSQ curves. CONCLUSIONS: The assessment of the TSQ of velopharyngeal port diameters and the TSD in the terminal closure period lead to a new dynamic interpretation of velopharyngeal closure patterns.