[Dysarthric movement disorders of the velopharynx]

In this study we developed another method for the detection of nasopharyngeal closing patterns. This investigation of dynamic closure patterns was based on flexible video-nasopharyngoscopy and was undertaken in both healthy subjects and patients with dysarthria. Quantitative assessments of pharyngeal wall excursions allowed evaluation of closure patterns which were then matched with a predefined, mathematically-based algorithm. The results showed that a greater velopharyngeal constriction was maintained in the following order: resonants, open vowels, forced expiration, closed vowels, consonants, and swallowing. Variations in phonetic expressions of phonemes mainly interfered with velum excursion, whereas the lateral pharyngeal mucosal wall was minimally involved and the posterior wall portions were unaffected. Velopharyngeal closure patterns varied with different tasks: the velum was mainly moved for phonetic parameters, while lateral and posterior pharyngeal wall motion was observed on a large scale for swallowing. Comparison of subject groups revealed that patients with dysarthrias had reduced velar motility, leading to a more frequent hypernasal sound. Here, lateral pharyngeal walls showed a variable motility that in some cases was even more than in healthy subjects. Both groups exhibited qualitatively comparable velopharyngeal closure patterns, but significant differences were proved in their distributions.