What Are the Causes of Unilateral Proptosis?

Unilateral proptosis is a condition in which an eye appears pushed out in comparison to the other eye. Another name for this condition is exophthalamos. Proptsosis is associated with Grave's disease. However, severe obesity, hyperthyroidism and Cushing's disease are conditions that may give the appearance of unilateral proptosis. Often, individuals with this disorder have an appearance that looks off-balance as one eye is popping out and the other appears normal. Unilateral protptosis is treated with medication and in rare cases surgery.

Graves' Disease

• The primary cause of unilateral proptosis is Graves' disease, according to the Merck Manual Online Medical Library. Graves' disease is a condition in which the thyroid is overactive and metabolism is abnormally high. Symptoms of Graves' disease include weight loss, increased appetite, insomnia and anxiety. Individuals with Graves' disease also experience a loss of the ability to produce tears. Other symptoms include eye muscle weakness, eye irritation, hyper-sensitivity to light and vision loss.

Orbital Tumors

• According to the Eye Cancer Network, another cause of unilateral proptosis can be orbital (eye) tumors. Tumors can grow behind the eye and push the eye forward out of the eye orbit. The result is that the affected eye may appear to be pop-eyed and out of balance with the face. Orbital tumors may be the result of lymphoma, vascular cancer or benign tumors of the eye. Additionally, tumors can start in the sinus cavity and extend up and behind the eye, resulting in unilateral proptosis. Treatment for this condition is surgery to remove the tumor.

Infections

• Another potential cause of unilateral proptosis can be infection of the eye, according to Michael Mercandetti, M.D., with Doctors Hospital, Sarasota. Infections of the eye can be viral or bacterial and may start initially in the sinus cavity. Treatment for this type of condition usually includes prescription antibiotics, particularly if the infection is problematic and is interfering with eyesight.

Trauma

• One of the most serious causes of unilateral proptosis is trauma to the eye area of the face. According to Dr. Mercandetti, trauma can include fractures to the orbital area of the face and to the areas immediately adjacent to the orbital area. In many instances as the trauma heals, the unilateral proptosis resolves and the eye begins to look normal. However, in cases of severe trauma, cosmetic and reconstructive surgery may be necessary.

Vascular Disease

• According to Dr. Mercandetti, another potential cause of unilateral proptosis can be vascular disease. If the blood vessels that supply the eye become inflamed or blocked, the eye will swell and push out of the eye socket. Another potential area where vascular disease can affect the appearance of the eyes is if a fistula or abnormal connection between blood vessels develops. Fistulas are often the result of trauma or injury to the affected area.