Cerebrospinal fluid collection due to spinal intradural arachnoid cyst (Q97285)

Cerebrospinal fluid collection due to arachnoid cyst, a collection that usually develops in the head, but may also develop around the spinal cord. It is named an arachnoid cyst because it occurs in the space between the brain (or spinal column) and the arachnoid membrane. If in the head, the cyst will grow between the brain and skull or in pockets around the brain. The cyst is usually filled with cerebrospinal fluid (CSF). The fluid accumulates in the cyst as the walls of the cyst do not permit drainage into the CSF system.