Short posterior ciliary artery insufficiency with hyperthermia (Uhthoff's symptom).

Transient visual blurring with heart or exercise (Uhthoff's symptom) is associated with multiple sclerosis. To our knowledge, this is the first report of its occurrence in cases of documented vascular disease. Two patients had insufficiency of the short posterior ciliary circulation. In one it was caused by a carotid occlusion and in the other by cranial (giant-cell, temporal) arteritis. The monocular blurring may have occurred during periods of relative arterial hypotension.