Pseudotumor cerebri occurs when the pressure inside your skull (intracranial pressure) increases, causing headaches and vision problems. The name means “ false brain tumor,” since its symptoms are similar to those caused by brain tumors. It occurs in 1 to 2 people in 100,000.
The exact cause of pseudo tumor cerebri is unknown, but it may be linked to an excess amount of cerebrospinal fluid within the skull. The fluid is produced in the brain and is eventually absorbed into the bloodstream. The increased intracranial pressure of pseudotumor cerebri may be a result of a problem in this absorption process.
In general, your intracranial pressure increases when the contents of your skull exceed its capacity. For example, a brain tumor generally increases your intracranial pressure because there’s no room for the tumor.
Symptoms mimic those of a brain tumor but no tumor is present. Pseudotumor cerebri can occur in children and adults, but is most common in obese women of childbearing age. About 4-21 obese women in 100,000 will develop the disorder. The increased intracranial pressure associated with pseudotumor cerebri can cause swelling of the optic nerve and result in vision loss.
Symptoms may include:
- Moderate to severe headaches that may originate behind your eyes and worsen with eye movement.
- Ringing in the ears that pulses in time with your heartbeat. (pulsatile tinnitus)
- Nausea, vomiting or dizziness
- Blurred or dimmed vision
- Brief episodes of blindness, which lasts only a few seconds and affects one or both eyes
- Difficulty seeing to the side
- Seeing light flashes (photophosia)
- Neck, shoulder or back pain
- Double vision
Risk factors for pseudotumor cerebri include:
- Medications including growth hormone, tetracycline and excessive vitamin A
- Other health issues including kidney disease and sleep apnea
Obesity dramatically increases a young woman’s risk of pseudo tumor cerebri. Women who are not obese who gain a moderate amount of weight may increase their risk. Losing extra pounds and maintaining a healthy weight may reduce your chances of developing this potentially sight-stealing disorder.
Complications including progressively worsening vision may eventually lead to blindness.
To diagnose your condition you will begin with a medical history and physical exam. An exam by an opthamologist may reveal a distinctive type of swelling affecting the optic nerve called papilledema. Visual field tests will diagnose blind spots in your vision. An MRI or CT Scan can be per formed to rule out other problems which may cause similar symptoms such as brain tumors and blood clots. A spinal tap (lumbar puncture) measures the pressure in your skull as well as sugar and protein levels in the cerebro-spinal fluid will exclude alternative diagnoses. The lumbar pressure measures the pressure of cerebrospinal fluid and is the definitive diagnostic test for pseudotumor cerebri.
The goal of the pseudotumor cerebri treatment is to improve your symptoms and keep your eye sight from worsening.
- Discontinue medications that can exacerbate the condition including oral contraceptives and some steroids.
- Medications can be used to control your symptoms:
- Glaucoma meds: reduce the production of cerebrospinal fluid
- Diuretics (water pills): reduce fluid retention
- Migraine medications ease the severe headaches.
- Weight loss may improve symptoms.
- Surgery is necessary if your vision becomes worse.
- Optic nerve sheath finestration-a window is cut in the membrane that surrounds the optic nerve. This allows the excess cerebro spinal fluid to escape.
- Spinal fluid shunt- a long, thin tube is inserted in the brain or lower spine to help drain away excess cebebro spinal fluid. The tubing is burrowed under your skin to your abdomen where the shunt discharges the excess fluid. This treatment is generally performed if other treatments have not relieved the condition.