• Headaches
• Nausea & vomiting
• Vision & hearing problems
• Developmental delays
• Vertigo & dizziness
• Walking or balance problems
• Behavioral changes
• Fluid on the brain (hydrocephalus)
• Seizures (rarely)

• Arachnoid (leptomeningeal) cyst. This sac of cerebrospinal fluid can develop as during infancy or in the womb and may go undiagnosed until after a traumatic head injury. When arachnoid cysts become large enough to cause brain pressure or other deformities, surgery may be required. A neurosurgeon may treat the cyst with a shunt or perform a procedure to create space around the fluid sac.
• Colloid cyst. These benign, gel-filled sacs develop in the third ventricle, a reservoir for cerebrospinal fluid. Abnormalities in this area may be life-threatening since they can block the flow of CSF and cause eventual hydrocephalus. Hydrocephalus is known for causing positional headaches, nausea and vomiting and even comas—which can lead to death. Large tumors should be surgically removed. In some cases, your PBSSM physician will insert a shunt (tube from the ventricles) to drain cerebrospinal fluid and relieve pressure on the brain.
• Dermoid cyst. This rare type of cyst is commonly diagnosed in younger children. Composed of normal tissue (follicles, skin cells, hair and sweat glands) growing in an abnormal location, a dermoid cyst may be found at the brain’s base, in the fourth ventricle, near the frontal lobes or in the lower portion of the spine. Dermoid cysts can be surgically removed when symptoms become problematic.
• Epidermoid cyst. Similar to a dermoid cyst, this type of non-cancerous tumor develops when tissue is trapped during brain and spinal cord formation. Epidermoid cysts grow slowly and are usually diagnosed during adulthood.  
• Pineal cyst. Occurring on the pineal gland in the center of the brain, pineal cysts are generally diagnosed during imaging for an unrelated issue. While these fluid sacs don’t usually cause problems, they may affect vision and require intervention in rare cases.

Some brain cysts are found during imaging or examinations conducted for other reasons. At times, these abnormalities are found when cyst-related symptoms interfere with a patient’s daily life. Diagnosis begins with a medical and symptom history and neurological exam followed by a CT scan or magnetic resonance imaging (MRI).