Pseudotumor cerebri is a condition in which the pressure inside the skull is increased. The brain is affected in a way that the condition appears to be -- but is not -- a tumor.

Idiopathic intracranial hypertension; Benign intracranial hypertension

The condition occurs more often in women than men, especially in obese women who are about to go through menopause. It is rare in infants, but can occur in children.

The cause is unknown.

Certain medicines can increase your risk of this condition. These medicines include:

• Birth control pills
• Cyclosporine
• Isotretinoin
• Minocycline
• Nalidixic acid
• Nitrofurantoin
• Phenytoin
• Steroids (starting or stopping them)
• Sulfa drugs
• Tamoxifen
• Tetracycline
• Vitamin A

The following factors are also related to this condition:

• Addison disease
• Chronic kidney failure
• Cushing's disease
• Hypoparathyroidism
• Iron deficiency anemia
• Obesity
• Onset of menstruation (menarche)
• Pregnancy

Symptoms include:

• Blurred vision
• Buzzing sound in the ears (tinnitus)
• Dizziness
• Double vision (diplopia)
• Nausea
• Vision loss

Symptoms may get worse during physical activity, especially when you tighten the stomach muscles.

The doctor will perform a physical exam. Signs of this condition include:

• Bulging anterior fontanelle
• Increased head size
• Swelling of the optic nerve in the back of the eye (papilledema)

Even though there is increased pressure in the skull, there is no change in alertness.

Tests that may be done include:

• CT scan of the head
• Eye exam, incluiding visual field testing
• MRI of the head with MR venography
• Lumbar puncture (spinal tap)

Diagnosis is made when other health conditions are ruled out. Several conditions may cause increased pressure in the skull, including:

• Hydrocephalus
• Tumor
• Venous sinus thrombosis

Treatment is aimed at the cause of the pseudotumor.

A lumbar puncture can help relieve pressure in the brain and prevent vision problems.

Other treatments may include:

• Fluid or salt restriction
• Medications such as corticosteroids, acetazolamide, and furosemide
• Shunting procedures to relieve pressure from spinal fluid buildup
• Surgery to relieve pressure on the optic nerve
• Weight loss

Patients will need to have their vision closely monitored. There can be vision loss, which is sometimes permanent. Follow-up MRI or CT scans may be done to rule out hidden cancer.

Sometimes the condition disappears on its own within 6 months. Symptoms can return in some persons. A small number of patients have symptoms that slowly get worse and lead to blindness.

Vision loss is a serious complication of this condition.

Call your health care provider if you or your child experiences the symptoms listed above.

DeAngelis LM. Tumors of the central nervous system and intracranial hypertension and hypotension. In: Goldman L, Schafer AI, eds. Goldman's Cecil Textbook of Medicine. 24th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 195.

Dhungana S, Sharrack B, Woodroofe N. Idiopathic intracranial hypertension.Acta Neurol Scand. 2010;121(2):71-82.

Pless ML. Pseudotumor cerebri. In: Kliegman RM, Stanton BF, St. Geme JW III, et al., eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 597.

Rosenberg GA. Brain edema and disorders of cerebrospinal fluid circulation. In: Daroff RB, Fenichel GM, Jankovic J, Mazziotta JC, eds. Bradley's Neurology in Clinical Practice. 6th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 59.