Exophthalmos (also called exophthalmus, exophthalmia, proptosis, or exorbitism)
Is a bulging of the eye anteriorly out of the orbit. Exophthalmos can be either bilateral (as is often seen in Graves' disease) or unilateral (as is often seen in an orbital tumor).
Symptoms:
Pain in the eyes
Dry eyes
Eye irritation
Sensitivity to light, known as photophobia
Lacrimation, or eye secretions and shedding of tears
Diplopia, which is double vision caused by the weakening of the eye muscles
Progressive blindness, if the optic nerve is compressed
Difficulty in moving eyes, as the eye muscles weaken