A midline cystic sac of meninges containing spinal tissue and CSF that herniates via a hole in the posterior vertebral arch is known as a Meningomyelocele. It is a birth defect that occurs when the spine and spinal cord do not develop completely. Hydrocephalus is the abnormal accumulation of Cerebrospinal fluid in the intracranial spaces.This happens when there is a problem with CSF production or absorption, or when the CSF channels become blocked. It causes the skull to expand and the cerebral ventricles to dilate

Meningomyelocele, Hydrocephalus, Lumbosacral region, Chiari Malformation