両側内耳奇形児の平衡機能と運動の発達について

Abstract

Children with inner ear anomalies resulting in severe hearing impairment may show deficits in head control and independent walking. In the present study we examined the vestibular function in children with bilateral inner ear anomalies using a rotation test, and investigated the impact of the anomalies on motor development. Children with the Michel anomaly, which is characterized by a lack of inner ear differentiation bilaterally, are markedly slow in developing head control and independent walking. As muscle tonus is increased with the myelinization of motor neurons, independent walking becomes possible. On the other hand, children with severe inner ear anomalies, such as bilateral common cavity deformity and incomplete partition type I (Mondini deformity), show vestibular ocular reflex by the rotation test as they age, and normal independent walking and running become possible. These results demonstrate that, although children with inner ear anomalies may be slow in motor development in their infancy, their motor function increases to a normal level as they grow.