What is the outlook for people with arachnoid cysts?

What is the outlook for people with arachnoid cysts?

Most arachnoid cysts never cause symptoms, but on the rare occasions that they do, treatment for arachnoid cysts usually relieves symptoms. But cysts can grow back or fill with fluid after treatment. If that happens, you may need another procedure to drain the fluid or remove the cyst.

Untreated, symptomatic arachnoid cysts can lead to permanent brain damage, severe pain, movement disorders and serious health problems. Rarely, untreated cysts can cause the skull to grow in an abnormal way. Complications from arachnoid cysts include:

• Bleeding: Blood vessels on the cyst wall can tear and bleed into the cyst, which can make it grow larger. When blood vessels tear and blood pools outside of the cyst, a hematoma can form.
• Leaking fluid: If trauma or injury damages the cyst, a CSF leak can result. The fluid can leak into other parts of the brain, causing severe health problems.