CASE
A 33-year-old woman presented to her primary care provider the day following a single episode of sudden blurred vision in the right eye. The problem had resolved completely within hours, and she had had no subsequent visual disturbances.
History Except for an elevated cholesterol level, the patient's medical history was noncontributory. It included hypothyroidism, chronic bronchitis, appendectomy, and three cesarean sections. She reported smoking one to two packs of cigarettes per day since the age of 16 but denied any alcohol or recreational drug use. Current medications were levothyroxine, pravastatin, and fish oil. Findings on past eye examinations had been normal, and there was no family history of stroke.
Evaluation The patient was alert and oriented to person, place, and time. Her speech was clear and fluent. Pupils were equal at 3 mm, and extraocular movements were normal. Her face was symmetrical, without evidence of droop, and intact to light touch; her tongue was positioned normally at the midline. She was able
to read small print with each eye individually.
Laboratory values, including ESR and lipid panel, were within normal limits. An ophthalmologist thought her lateral visual fields were slightly decreased bilaterally. On funduscopic examination, he noted a possible "dilated retinal vessel," suggesting a vascular blockage. CT angiography of the neck and cerebral vessels revealed a 6-mm right posterior communicating aneurysm, a 3-mm left posterior communicating artery aneurysm, and a striking "string of beads" appearance of both proximal internal carotid arteries. Catheter-based digital subtraction angiography confirmed the diagnosis (Figure 1).
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