Abstract Otology 2000 A19-16

Chih Ying Su MD

Chief of Dept. Otolaryngology Chang Gung Memorial Hospital TWN-NiaoSung HsiangKaohsiung Hsien

The cleft palate population has a high prevalence of otitis media with effusion. It is believed that one of the pathogenetic factors of eustachian tube dysfunction in the cleft palate patients is an inability of the paratubal muscles to dilate the eustachian tube actively during swallowing. This study was designed to evaluate the swallowing and phonation contraction activities of the tensor and levator veli palatini muscles which were recorded by a transnasal electromyographic(EMG) recording method. Twenty cleft palate patients with forty sides of tensor and levator muscles were involved in this study. The results revealed that the swallowing and phonation contraction EMG activities of levator muscles in cleft palate palate patients were markedly decreased. The duration of swallowing EMG activities of the levator muscle was shorter than that of the normal controls. However, the swallowing EMG activities of tensor muscle in cleft palate patients presented normal and even increased. These results suggested that eustachian tube dysfuncton in cleft palate patients may be not due to a poor contractility of the tensor muslce.The velopharyngeal insufficiency of cleft palate patients was closely related to not only the clefting of the palate but also the poor contractility of the levator muscle.