Painless transient monocular loss of vision resulting from angle-closure glaucoma.

The main symptoms of acute primary angle-closure glaucoma (PACG) include pain in the head and/or the eyes in addition to the characteristic halo and blurred vision. When loss of vision is accompanied by such pain, PACG is usually suspected. However, no information has been available regarding painless acute angle-closure glaucoma. Recently, we treated a patient with painless acute PACG mimicking amaurosis fugax as a type of transient ischemic attack. Generally, amaurosis fugax causes transient monocular loss of vision due to occlusion of the ophthalmic artery. The formation of microemboli derived from the heart or carotid artery and/or the occurrence of some hemodynamic abnormality due to arteriosclerosis is closely related to amaurosis fugax, and most cases are complicated by intracranial or extracranial arterial lesions. In the present case, we provisionally diagnosed transient amaurosis fugax which, however, was shown by additional ocular testing to be painless PACG. Herein we describe our diagnostic process and the outcome.