Orbital Pseudotumor

Orbital Pseudotumor

Definition

Lymphocytic orbital tumor of unknown origin.

Symptoms and findings: 

Painful, moderately severe inflammatory reactionwith eyelid swelling, chemosis, and unilateral or bilateral exophthalmos. Involvement of the ocular muscles results in limited motility with diplopia.

Diagnostic considerations: 

The CT and MR imageswill show diffuse soft-tissue swelling. A biopsy is required to confirm the diagnosis.

Occasionally the CT image will simulate an infiltrative tumor.

Differential diagnosis: 

Various disorders should be excluded. These includeGraves’ disease and orbital cellulitis, which is usually bacterial. Special forms of orbital pseudotumor include myositis and Tolosa–Hunt syndrome (pain-ful total ophthalmoplegia produced by an idiopathic granuloma at the apex of the orbit).

Treatment: 

High-dosesystemic cortisone(initially 100 mg of prednisone)usually leads to remission. Orbital radiation therapy or surgical intervention may be indicated in cases that fail to respond to treatment.