A 45-year-old man with a history of smoking experienced sudden onset of loss of vision on his left side and transitory left hemiparesis. There was no history of recent trauma. Examination showed mild left hemiparesis and hypoesthesia, and left homonymous hemianopsia. Cranial computed tomographic imaging findings at admission were normal. Magnetic resonance imaging demonstrated a right occipital lobe infarction in the territory of the right posterior cerebral artery (PCA) (Figure, A and B). Transcranial Doppler sonography demonstrated collateral blood supply to the right hemisphere via the anterior communicating artery and no flow on the right carotid siphon or right PCA. Magnetic resonance angiographic imaging showed occlusion of both the right internal carotid artery (ICA) and the second portion of the right PCA (P2). There was also asymmetry of the proximal portion (P1) of the PCAs with a hypoplastic right P1, suggesting that the right occipital lobe was originally supplied by the right ICA (fetal pattern) (Figure, D). Digital subtraction angiography showed a cone-shaped complete occlusion of the right ICA, highly suggestive of dissection (Figure, C). Posterior cerebral artery infarct related to embolization from ICA dissection, associated with a persistent fetal configuration of the right PCA, was diagnosed. The patient was treated with anticoagulation therapy.
Christoph DDH, Souza-Lima F, Saporta MADC, de Freitas GR. Isolated Posterior Cerebral Artery Infarction Caused by Carotid Artery Dissection. Arch Neurol. 2009;66(8):1034. doi:10.1001/archneurol.2009.147