[Infarction in the territory of the anterior choroidal artery due to embolic occlusion of the internal carotid artery--report of two cases].

A case with infarction in the territory of the anterior choroidal artery (AChA) due to embolic occlusion of the internal carotid artery (ICA) is rare. We described two cases and investigated the mechanism of the territory of the AChA. Case 1 was a 69-year-old man. Case 2 was a 71-year-old woman. The neurological examination in both cases showed left homonymous hemianopsia, left facial palsy, left hemiparesis and left hemisensory disturbance. CT scan in these cases showed infarctions of the right uncus, amygdaloid nucleus, genu and posterior limb of the internal capsule, globus pallidus, lateral geniculate body and tail of the caudate nucleus. The right common carotid angiogram showed a complete occlusion of the ICA at its cervical segment in case 1 and at its carotid siphon in case 2. In both cases, the left carotid injection visualized the right anterior cerebral artery and right middle cerebral artery via the anterior communicating artery well, but the right AChA was not visualized. In case 1, the collateral pathways from the right external carotid artery (ECA) and the right posterior communicating artery (PCoA) to the right ICA were not supplied and the precommunicating segment of the right posterior cerebral artery was hypoplastic. In case 2, the collateral pathway from the right ECA to the right ICA was not supplied.(ABSTRACT TRUNCATED AT 250 WORDS)