Sudden unilateral decrease in vision: JAMA case report
A previously healthy man in his 50s presented with a 1-day history of sudden painful decreased vision in the right eye. On examination, his visual acuity was counting fingers at 3 ft OD and 20/20 OS.

A slitlamp examination of the right eye revealed conjunctival hyperemia, nongranulomatous keratic precipitates in the inferior half of the corneal endothelium, and 3+ cells in the anterior chamber, while results of a dilated fundus examination showed 1+ vitritis, 360° of optic nerve swelling, intraretinal hemorrhages predominantly along the distribution of the retinal arteries and arterioles, and perivascular sheathing, as well as macula involving retinal whitening, thickening, and subretinal fluid (Figure, A).

Fluorescein angiography revealed late vascular leakage with both arterial and venous involvement (Figure, B) and peripheral ischemia. Examination of the left eye revealed no abnormalities.

Fina Dx was Acute retinal necrosis, posterior pole variant, from herpes simplex virus 1

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