Ｏｃｕｌｏｐａｌａｔａｌ ｍｙｏｃ１ｏｎｕｓ症例とＰａｌａｔａ１ ｍｙｏｃｌｏｎｕｓ症例の比較 電気眼振図と聴性脳幹反応にょる検討

Abstract

We studied six patients with palatal myoclonus (p.m.), two of whom had oculopalatal myoclonus (o.p.m.) and four p.m. only. We used Electronystagmography (ENG) and Auditory Brainstem Response (ABR) to compare them.In the two o.p.m. patients pontine hemorrhage was seen in the lateral brainstem in Brain CT scans. They had a decreased total slow phase velocity of OKN, prolonged latency of waves III and V, and disappearance of ABR after wave III. These findings indicate brainstem disturbances. Cerebellar and pontine lesions were seen in Brain CT scans of two. Three of the four patients with p.m. of the four had normal OKN but the other two had decreased total slow phase velocity. Two had a normal ABR, and the other two had prolongation of latency waves III and V. These abnormal findings must be caused by the fact that the relaying nuclei of the auditory brainstem passway are near the central tegmental tract in the Guillain Mollaret triangle.We conclude that ABR can be used as an aid to detect brainstem disorders that cannot be found by CT, MRI or OKN and can also exclude the possibility of cerebellar disorders.