An encephalocele is a rare birth defect that occurs early in a woman’s pregnancy when a section of the developing infant’s skull does not close completely. An infant’s brain and spinal cord (central nervous system) normaly develop inside a structure called the neural tube. When the neural tube does not close properly, part of the infant’s brain may protrude through the section that has not completely closed in the skull. A more severe form of encephalocele is when part of the membrane that covers the brain and spinal cord (meninges) and cerebrospinal fluid (CSF) also protrude through the opening in the skull. Either skin or a thin membrane will cover the portion of the brain which is characterized by sac-like protrusions of the brain and the membranes that cover it through openings in the skull.
An encephalocele can be located on the head in:
- the base of the skull
- the area of the nose, sinuses and forehead
- From the top of the skull around to the back of the skull at the midline