Ependymoblastoma in a Holstein Heifer

10 カ月齢のホルスタイン種雌育成牛が急性に斜頸，旋回，後弓反張，意識混濁の症状を呈した．大脳皮質壊死症を疑い，ビタミンB1 製剤，コルチコステロイドおよび抗生物質による治療を実施したが反応せず，予後不良と判定された．病理解剖により小脳に直径35. cm 大の腫瘤が確認され，左右側脳室および中脳水道の拡張がみられた．本症例は小脳腫瘍による周辺部の圧迫および腫瘍の二次的圧迫による脳脊髄液流出障害により発生した内水頭症により，小脳徴候だけでなく大脳および脳幹症状も出現したものと考えられた．病理組織学的検索の結果，本症例は上衣芽腫と診断された．A 10-month-old female Holstein heifer showed a sudden onset of clinical symptoms of head tilt，circling， increased extensor tone of all legs. and decreased level of consciousness. Cerebrocortical necrosis was suspected， and an administration of vitamin B1， corticosteroids，and anti-biotic was performed without a successful response. At necropsy，a neoplastic mass with a diameter of 3.5 cm in the cerebellum，dilated lateral ventricles on both sides and enlargement of the aqueducts cerebra were found. Findings suggest that cerebral cortex and brainstem signs had appeared as wel1 as cerebellum signs through compression of the brainstem by cerebellar tumor and secondary hydrocephalus caused by obstruction of the cerebrospinal fluid. The neoplastic mass was diagnosed as ependymoblastoma by histopathological examination