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.