Axial myopia. A neglected cause of proptosis.

Ten patients who had unilateral proptosis ranging from 2.5 to 4.0 mm were found to have axial myopia confirmed by ultrasonography and, in one case, by computerized tomography. The historical features emphasized include an acquired painless bulging eye, amblyopia, and a stable visual acuity. Noteworthy features on ophthalmologic examination include a difference in visual acuity and refraction between the two eyes, a difference in the lenses on inspection of the patient's glasses, and an ipsillateral myopic fundus. Careful history taking, examination, ultrasonographic evaluation, and inspection of old photographs will separate this group of patients and avoid unnecessary endocrine studies, angiography, and costly neuroradiologic investigations. Finally, it must be recognized that coexisting disease must be evaluated as if the proptosis did not exist.