A case of presumed embolic transient ischemic episodes and multifocal infarcts to the occipital and parietal cortices and the cerebellum of a young woman with ulcerative colitis is reported. These episodes were manifested by multifocal neurologic deficits including cortical blindness, visual hallucinations, and homonymous hemianopsia. They correlated with parenteral nutrition via a central line, presumed venous, but found to be in the subclavian artery. The complications of central venous lines are reviewed. The need for attention to neighborhood structures and unexpected symptoms, in view of the less well-recognized arterial embolic complications is emphasized.