Hydrocephalus in Myelomeningocele

Infant with a native myelomeningocele which protrudes as a bag-like thoracolumbar midline mass over the level of the skin, and is partially covered by a thin epithelium. Mainly the muscles of both lower legs and of the right thigh are atrophic due to a paralysis. Notice the macrocrania due to a hydrocephalus which is combined with spina bifida in more than 80 %. Its cause is an Arnold Chiari malformation type 2, and often an additional aqueductal stenosis.