reactive to light, with an intact near reaction (figure, E). There was marked hypophonia without dysarthria, and bilateral facial paresis, left greater than right. There was left hemiparesis (proximal left arm 4/5, left wrist and hand 1/5, and left leg 4/5) without ataxia, and there was a left Babinski sign. There were no sensory abnormalities.Routine laboratory studies were normal. The serum RPR was positive at 1:32, and serum FTA-ABS was also positive. HIV testing was negative.The patient was treated with IV heparin, and repeat MRI and MRA of the brain were obtained. A right medial pontine stroke was confirmed on DWI (figure, A). MRA showed loss of signal in the mid-basilar artery (figure, B). Cerebral angiography showed a mid-basilar stenosis with a positive string sign and no evidence for dissection (figure, C). There was robust collateral flow from the anterior to posterior circulations (figure, D). There were no areas of stenosis in the anterior circulation. There were mild focal stenoses in the proximal left subclavian artery and the origin of the left vertebral artery.