脊髄髄膜瘤
a congenital defect of the central nervous system in which a sac containing part of the spinal cord and its meninges protrude through a gap in the vertebral column frequently accompanied by hydrocephalus and mental retardation
中枢神経系の先天性欠損で、脊髄の嚢を含んだ部分とその髄膜が脊柱の狭間からはみ出しているというもの しばしば水頭症と精神薄弱を伴う