MIDDLE CEREBRAL-ARTERY VARIATIONS - DUPLICATED AND ACCESSORY ARTERIES

PURPOSE: Our goal was to analyze the anatomic similarity between the d uplicated middle cerebral artery (MCA) and the accessory MCA and their relationship to the early branches of the MCA. METHODS: We reviewed s tereoscopic angiograms of duplicated MCAs in four patients and accesso ry MCAs in four patients with reference to the origin, size, and corti cal supply of these anomalous vessels, along with the presence of perf orating arteries and the recurrent artery of Heubner (RAH). RESULTS: T he duplicated MCAs supplied the cortical territory of the temporopolar and the anterior temporal and/or middle temporal arteries, The access ory MCAs supplied the cortical territory of the orbitofrontal and/or p refrontal arteries, The duplicated MCAs had perforating arteries in th ree of four cases and coexisted with the RAH in three of four cases, w hereas the main MCA had perforating arteries in all four cases, The ac cessory MCA had perforating arteries in all four cases and coexisted w ith the RAH in three of four cases, whereas the main MCA had perforati ng arteries in one of four cases. CONCLUSION: A consistent cortical su pply by the duplicated MCA and the accessory MCA to the anterior tempo ral lobe and the anterior frontal lobe, respectively, and its similari ty to the cortical supply by the early branches of the MCA suggest tha t development of duplicated and/or accessory MCAs is an anomalously ea rly ramification of the early branches of the MCA.