According to The American Brain Tumor Association, a brain cyst is similar to other cysts that form on the body. It can be filled with, fluid, blood, minerals or tissue. Brain cysts are usually benign and sometimes never cause any symptoms. These cysts can form anywhere in the brain and can sometimes cause serious problems. The treatment for a brain cyst will vary depending on location and type of cyst it is.
Arachnoid cysts are found in the meninges, a thin layer of membrane that covers the brain and spinal cord. According to Dr. David Schiff, the cyst usually contains cerebrospinal fluid. The treatment for this type of cyst may consist of simply waiting to see how the cyst develops. The physician may want to see the patient back periodically to have CAT scans or MRI's. If the cyst is in a location that causes problematic symptoms, then surgery may be needed. The surgical procedure involves draining the fluid from the cyst either through aspiration with a needle or with a shunt. However, the cyst wall has to also be removed to prevent regrowth.
Colloid cysts usually start developing while we are still in the womb. According to Schiff, a colloid cyst develops during the embryonic development of the central nervous system. The cyst fills with a gelatinous substance called colloid. The substance consists of blood, minerals and cholesterol crystals. The cysts usually do not cause any problems until you reach adulthood. However once it has grown enough it causes fluid to back up and cause increased pressure in the brain. At this stage, the cysts can cause serious problems such as hydrocephalus, loss of consciousness and difficulty walking. The treatment for these cysts consists of draining the fluid and thus relieving the pressure. Because of the cyst's location in the brain it is currently (2009) not possible to remove it, therefore fluid drainage is the only form of treatment at this time.
According to Schiff, scientists believe dermoid cysts form during fetal development. Dermoid cysts are caused when the cells that would help to form the face get trapped inside the brain. As a result, dermoid cysts are usually filled with hair, glands and cartilage. They are usually located on the lower back portion of the brain and can sometimes be located in the meninges of the brain. The treatment of these cysts commonly involves surgical removal. If the cyst wall is not removed, it may grow back.
The epidermoid cyst develops in the much the same way that a dermoid cyst develops. However, according to Schiff, these cysts usually contain a thick yellow fluid that has hair, skin oil and cholesterol crystals and do not contain glands. Epidermoid cysts usually occur in the area where the brain meets the spinal cord. Occasionally, the cysts will spontaneously tear open and leak the contents into the brain and spinal cord. Epidermoid cysts need to be completely removed, and this is done through surgery.
It is unknown why pineal cysts develop, but they are sometimes found by accident when doing an MRI. The tumour can usually be found at the base of the brain where it meets the spinal cord. The symptoms of this cyst may include difficulty looking upwards, headaches or hydrocephalus. According to the website for Nervous System Disorders, some people never experience any symptoms at all. As a result, the treatment for a pineal cyst may be to do nothing. However, if symptoms do develop, surgery will need to be done to completely remove it.