[Nasopharyngoscopic analysis of the velopharyngeal function in normal and cleft lip and palate patients]

The speech problem in patients born with cleft lip and palate is mainly due to the insufficiency of the velopharyngeal (VP) valving mechanism, manifested as in visually seen nasal emission, and auditorily perceived hypernasality and articulation disorders. Evaluations of resonance and VP function can be conducted by: (1) perceptual rating scale based on speech pathologist's subjective judgement and (2) objective instrumental assessment, by the use of specific instrument. Nasopharyngoscopy has been commonly used clinically to diagnose VP function. The purpose of this study is: using nasopharyngoscopy to investigate the differences in VP mechanism between those with VP competence and VP incompetence in the dimension of velar displacement, lateral pharyngeal wall (LPW) displacement, degree of VP closure and pattern of VP closure. Ninty-eight subjects were studied from June 1990 to August 1991. They were divided into 4 groups: (1) group 1: normals with normal speech; (2) group 2: cleft of lip only, with normal speech; (3) group 3: cleft palate without nasal emission, but normal articulation; (4) group 4: cleft palate with nasal emission, with or without articulation error. Age range was from 6-47 years old with equal sex distribution. Ten Chinese sentences were used for standard test sentences, and were grouped according to Mandarin phonological distinctive features into 5 categories: (1) nasals; (2) vowels; (3) plosives; (4) fricatives/affricates; (5) connected number counting. The result indicates that the insufficient velar displacement to contact posterior pharyngeal wall is a determining factor causing velopharyngeal insufficiency in group 4; however, the lateral pharyngeal wall movement is not significantly different among 4 groups. Coronal pattern of velopharyngeal closure is the most common pattern among 4 groups of speakers.