what congenital cerebral cysts means
CSF is a naturally-occurring protective fluid that surrounds the brain and spinal column. The fluid accumulates in the cyst as the walls of the cyst do not permit drainage into the CSF system. Arachnoid cysts in children are usually congenital, or present at birth. These cysts are called primary arachnoid cysts. Arachnoid cysts that are not congenital, but develop later in life, are called secondary arachnoid cysts. Primary arachnoid cysts are more common than secondary arachnoid cysts.