What is arachnoid cysts?

Some arachnoid cysts don't cause any symptoms. If you do have symptoms, they may include a headache, nausea and vomiting, seizures, hearing and vision problems, or balance problems. You may also have pain in your back and legs or tingling or numbness in your legs or arms.

If you have no symptoms, treatment may not be needed. You may have follow-up appointments and regular MRIs. This is to see if the cyst is growing. Treatment may be a surgery to place a shunt or to remove part or all of the cyst. This may allow the fluid to drain.

An arachnoid cyst is a fluid-filled sac that grows between the arachnoid membrane and the brain or spinal cord. The arachnoid membrane is one of the layers of tissue that cover the brain and spinal cord.