Pseudotumor cerebri (SOO-doe-too-mur SER-uh-bry) occurs when the pressure inside your skull (intracranial pressure) increases for no obvious reason. Symptoms mimic those of a brain tumor, but no tumor is present. Pseudotumor cerebri can occur in children and adults, but it’s most common in obese women of childbearing age. When no underlying cause for the increased intracranial pressure can be discovered, pseudotumor cerebri may also be called idiopathic intracranial hypertension. The increased intracranial pressure associated with pseudotumor cerebri can cause swelling of the optic nerve and result in vision loss. Medications often can reduce this pressure, but in some cases, surgery is necessary.
Pseudotumor cerebri signs and 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, lasting only a few seconds and affecting one or both eyes (visual obscurations)
- Difficulty seeing to the side
- Double vision (diplopia)
- Seeing light flashes (photopsia)
- Neck, shoulder or back pain
The exact cause of pseudotumor cerebri in most individuals is unknown, but it may be linked to an excess amount of cerebrospinal fluid within the bony confines of your skull.
Your brain and spinal cord are surrounded by cerebrospinal fluid, which acts like a cushion to protect these vital tissues from injury. This fluid is produced in the brain and eventually is 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. The same thing happens if your brain swells or if you have too much cerebrospinal fluid.
Several studies indicate that many people with pseudotumor cerebri have a narrowing (stenosis) in two large sinuses in the brain (transverse sinuses). Studies are determining whether this is an effect or a cause of the condition.
he goal of pseudotumor cerebri treatment is to improve your symptoms and keep your eyesight from worsening. Your doctor may prescribe medications to control your symptoms.
If you’re obese, your doctor will recommend weight loss. You may work with a dietitian to help with your weight-loss goals. Losing weight may improve your symptoms. Some people who are morbidly obese may benefit from weight-loss programs or gastric surgery to lose weight.
If your vision worsens, surgery to reduce the pressure around your optic nerve or to decrease the intracranial pressure may be necessary. Once you’ve had pseudotumor cerebri, you should have your vision checked regularly.
- Glaucoma drugs. One of the first drugs usually tried is acetazolamide (Diamox), a glaucoma drug. This medication may reduce the production of cerebrospinal fluid. Also, it has been shown to improve symptoms in 47 to 67 percent of people.
Possible side effects include stomach upset, fatigue, tingling of fingers, toes and mouth, and kidney stones.
- Diuretics. If acetazolamide alone isn’t effective, it’s sometimes combined with furosemide (Lasix), a potent diuretic that reduces fluid retention by increasing urine output.
- Migraine medications. Medications usually prescribed to relieve migraines can sometimes ease the severe headaches that often accompany pseudotumor cerebri.
- Optic nerve sheath fenestration. In this procedure, a surgeon cuts a window into the membrane that surrounds the optic nerve. This allows excess cerebrospinal fluid to escape.Vision stabilizes or improves in most cases. Most people who have this procedure done on one eye notice a benefit for both eyes. However, this surgery isn’t always successful and may even increase vision problems.
- Spinal fluid shunt. In another type of surgery, your doctor inserts a long, thin tube (shunt) into your brain or lower spine to help drain away excess cerebrospinal fluid.The tubing is burrowed under your skin to your abdomen, where the shunt discharges the excess fluid. Symptoms may improve for some people who undergo this procedure.However, shunts can become clogged and often require additional surgeries to keep them working properly. Complications can include low-pressure headaches and infections.This procedure is generally only a treatment option if other treatments haven’t relieved your condition.