Acute unilateral visual disturbance

A previously healthy 37-year-old runner presented to his primary care physician with acute-onset floaters and scotoma in his left eye, which he first noticed less than 24 hours earlier. He denied eye pain, diplopia, headache, fever, chills, slurred speech, weakness, or other focal neurologic deficits. His vital signs were normal.

Despite the acute visual disturbances, visual acuity was 20/20 in both eyes with corrective lenses; pupils were equal, round, and reactive to light and accommodation; and extraocular movements were intact. On a dilated funduscopic exam, the physician discovered edema of the optic cup, tortuous vasculature, and microhemorrhages in the left eye (FIGURE).

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