Definition
The abnormal protrusion of one or both eyeballs.

Alternative Names
Protruding eyes; Exophthalmos; Proptosis; Bulging eyes

Considerations
Prominent, but not bulging, eyes may be a family characteristic. Bulging eyes should receive prompt attention. Bulging of a single eye, especially in children, is a very significant sign and should be evaluated immediately.

Hyperthyroidism (Graves' disease) is probably the most common cause of bulging eyes (exophthalmos). With this condition, the eyes don't blink very often and seem to have a staring quality. In most people, you shouldn't be able to see any white between the top of the iris (the colored part of the eye) and the upper eyelid, so this finding is usually a good indication that the eye bulging is definitely abnormal. The eye changes develop slowly and family members may not notice until the condition is relatively advanced. Photographs (such as from a driver's license) often draw attention to the bulging when it may have gone unnoticed previously.

Common Causes
hyperthyroidism
Graves' disease
histiocytosis
rhabdomyosarcoma
neuroblastoma
leukemia
orbital cellulitis (or periorbital cellulitis)
iatrogenic hyperthyroidism
hemangioma
glaucoma

Home Care
The underlying cause of this symptom needs to be treated by a health care provider. Because bulging eyes can cause a person to be self-conscious, emotional support is important.

Call your health care provider if
you have bulging eyes and the cause has not yet been diagnosed.
bulging eyes are accompanied by other symptoms.

What to expect at your health care provider's office
A history will be obtained and physical examination performed.

Medical history questions may include:

Are both eyes affected?
When did you first notice bulging eyes?
Is it getting worse?
What other symptoms are present?
Diagnostic tests:

A slit-lamp examination may be ordered. Blood testing for thyroid disease may be performed.

Intervention:
Artificial tears may be given to lubricate the eye(s). Other treatments will depend on the cause.