Two cases of anomalous origin of the anterior cerebral artery (ACA) associated with occlusive cerebrovascular diseases are presented.
Case 1, a 4-year-old boy, was admitted because of right-sided hemiparesis. Cerebral angiography revealed moyamoya disease and an anomalous artery originating at the right carotid siphon to join the ACA. The right ophthalmic artery and bilateral A, segment of the ACA were hypoplastic. The anomalous ACA had been gradually occluded in the course of the progression of moyamoya disease. Case 2, a 2-year-old boy, was admitted with right-sided hemiparesis following a nonpenetrating blunt head injury. Cerebral angiography revealed severe stenosis at the cervical segment of the left internal carotid artery and the anomalous origin of ACA on the right. This anomalous artery joined the anterior communicating artery to perfuse both ACA territories.
In the past, this anomalous artery has only been debated in view of its embryological interest, but it should contribute as a circulatory collateral pathway in association with occlusive cerebrovascular diseases.
