Intermediate
Technical
IVT
arachnoid cyst
A benign fluid-filled sac that develops between the arachnoid membrane and the brain or spinal cord.
Full Definition
Arachnoid cysts are congenital or acquired cerebrospinal fluid-filled spaces that occur within the arachnoid membrane layers. These cysts are typically asymptomatic but can cause neurological symptoms if they grow large enough to compress adjacent brain tissue. They are most commonly found in the middle cranial fossa and are often discovered incidentally on neuroimaging studies.
In Context
- "MRI revealed a large arachnoid cyst in the left temporal region." — Radiology report
- "The arachnoid cyst was deemed incidental and required no intervention." — Consultation note
Also known as
leptomeningeal cyst
Don't confuse with
epidermoid cyst
dermoid cyst
porencephalic cyst