On finding striated muscle in the brain.

Well-developed striated muscle was found in the leptomeninges of a 2 day old infant with a 13-15 trisomy defect and multiple congenital anomalies. Except for arhinencephaly, minor sulcal abnormalities, and scattered microscopic cerebellar dysplasias the brain was well formed. The extreme rarity of this finding is noted and an attempt is made to explain it on an embryological basis. The implications of this observation in relation to some central nervous system tumours containing striated muscle are briefly discussed.