Imaging and differential diagnosis of the large eye.

The initial step in the differential diagnosis of an enlarged eye is to determine whether an intraocular mass is present. The globe may be expanded by a mass, seen mainly in children with retinoblastoma. Buphthalmos with or without neurofibromatosis also enlarges the eye. Diffuse enlargement may be associated with a connective tissue disorder or be related to axial myopia. Focal enlargement represents staphyloma, which can be unilateral or bilateral. In the presence of one small eye, the normal-sized eye may be incorrectly diagnosed as large.