The orbit is the bony pyramid-shaped cavity of the skull that contains and protects the eyeball and associated structures. Orbital pseudotumor is a swelling of the orbital tissues behind the eye, but unlike cancerous tumors, it cannot invade tissues or spread elsewhere.

Causes, incidence, and risk factors

The cause is unknown. No risk factors are known.

Signs and tests

The changes of pseudotumor are obvious on examination of the eye. Special studies with ultrasound, x-ray, or biopsy may be needed to differentiate pseudotumor from true tumor.

Treatment

Mild cases may regress without treatment. More severe cases will usually respond to treatment with corticosteroids. Very severe cases may develop damaging pressure on the eye and require surgical movement of the bones of the orbit to decompress the eyeball.

Expectations (prognosis)

Most cases are mild and do well. Severe cases may be resistant to treatment and visual loss may occur. The disease usually involves only one eye.

Complications

Severe cases may push the eye forward to the extent that the lids can no longer protect the cornea, and damage to cornea clarity or corneal ulcer may occur. The ability of the eye muscles to aim the eye may suffer interference, and double vision may result.

Calling your health care provider

Patients with pseudotumor will be closely followed by an ophthalmologist with experience in treatment of orbital disease. If irritation of the cornea, redness, pain, or decreased vision occurs, urgent evaluation should be accomplished.

Prevention

No preventive measures are known.