Pseudotumor cerebri is a rare but potentially serious neurological disorder in which pressure inside the skull (intracranial pressure) increases with no identifiable cause. It causes symptoms that mimic those of a brain tumor (e.g., headaches, dizziness, vision loss), although no tumor can be found.

Pseudotumor cerebri, also known as primary intracranial hypertension, is one type of intracranial hypertension. The other type is secondary intracranial hypertension, in which the condition has a known cause. Possible causes of secondary intracranial hypertension may include brain tumors, hydrocephalus, infection, certain medications, specific disease states (e.g., kidney failure) and excessive vitamin A intake.

Although the cause of pseudotumor cerebri is unknown, certain factors increase the risk of developing the disorder. These include female gender, obesity, and being between the ages of 15 and 50 years. According to the Intracranial Hypertension Research Foundation, among overweight women of childbearing age are 20 times more likely to be diagnosed with pseudotumor cerebri in comparison to the general population.

Diagnosis of pseudotumor cerebri is one of exclusion, in that it requires a physician to eliminate other possible causes of a patient’s symptoms. This is likely to involve physical and neurological examinations, as well as imaging tests, blood tests and a spinal tap.

Once a patient is diagnosed with pseudotumor cerebri, treatment involves methods of reducing intracranial pressure. In many cases, medications are used. When used in conjunction with dietary changes and weight loss, medical therapy is usually successful in treating the problem. In some cases, surgery may be necessary to drain excess cerebrospinal fluid and to relieve intracranial pressure. Surgery may also be necessary to treat problems of vision loss that do not respond to other treatments.

There is no known way to prevent pseudotumor cerebri, although (especially for overweight young women), losing weight may be of help.