Any or all of the structures within the eye socket (orbit) may become inflamed because of a bodywide inflammatory disorder or an inflammatory disorder that affects only the orbit.
(See also Introduction to Eye Socket Disorders.)
People of all ages can be affected. Inflammation can be brief or long lasting, may or may not be caused by an infection, and can recur.
Causes of Orbital Inflammation
Inflammation of the orbit can be the result of a bodywide (systemic) inflammatory disorder. Sometimes the inflammation affects only the orbit. Inflammation can be caused by infection or by a noninfectious disorder. Inflammation of the orbit due to infection that affects the eyelid, skin, and tissues around the front of the eye is called preseptal cellulitis. Inflammation due to infection that affects the tissue within the orbit and around and behind the eye is called orbital cellulitis. Noninfectious orbital inflammation has many causes. The most common cause of noninfectious inflammation of the eye socket is thyroid eye disease (also known as Graves ophthalmopathy).
Systemic inflammatory disorders that affect the eye/orbit include granulomatosis with polyangiitis (formerly known as Wegener granulomatosis), in which there is generalized inflammation of blood vessels (called vasculitis). Another type of inflammation is called IgG4-related orbital inflammation (see also IgG4-Related Disease). IgG4-related orbital inflammation can affect the same structures as granulomatosis with polyangiitis but typically has fewer symptoms.
Inflammatory disorders that affect only the eye include scleritis, in which the white coat of the eye (sclera) becomes inflamed. Eyelid disorders with inflammation are discussed elsewhere. Inflammation affecting any or all parts of the orbit is called inflammatory orbital pseudotumor (which is not really a tumor and is not a cancer) or nonspecific orbital inflammation. Inflammation affecting the tear (lacrimal) gland, located at the upper outer edge of the orbit (see figure Where Tears Come From), is called dacryoadenitis. Inflammation affecting one of the muscles that move the eye is called myositis.
Symptoms of Orbital Inflammation
Symptoms vary depending on which structures are actually inflamed. In general, symptoms start rather suddenly, typically over a few days. Pain and redness of the eyeball or eyelid usually occur. Pain can be severe and incapacitating at times. Abnormal bulging of the eyes (proptosis), double vision, and vision loss are also possible. Symptoms related to IgG4-related orbital inflammation, on the other hand, are usually minimal. Rarely is there any discomfort, but rather proptosis and eyelid swelling are common. Other symptoms depend upon the disorder causing the orbital inflammation.
Diagnosis of Orbital Inflammation
Computed tomography or magnetic resonance imaging
Biopsy
Other tests to determine the cause
Computed tomography (CT) or magnetic resonance imaging (MRI) is done. A doctor may do other blood tests and take a sample from the inflamed area for examination under a microscope (biopsy) to determine the cause.
Treatment of Orbital Inflammation
Medications to treat inflammation (corticosteroids)
Radiation therapy or medications to change immune response and treat the underlying cause
Sometimes surgery is needed to help resolve or prevent progression of thyroid eye disease.
