Posterior Communicating Artery Giving Rise to Shared-Origin Anterior Choroidal Artery: Case Illustration.

BACKGROUND: The origin point of the anterior choroidal artery (AChA) is variable, typically arising from the supraclinoid internal carotid artery (ICA) distal to the posterior communicating artery (PComA) on either the posterolateral or posterior aspect of the ICA. Variations of AChA origin have important clinical implications, and rare origins reported previously include the ICA bifurcation and middle cerebral artery. We provide illustrations of a case of a shared-origin PComA and AChA. CASE DESCRIPTION: A young girl presented with intracranial hemorrhage and underwent angiography to evaluate for an underlying cause. Ultimately, 3-dimensional rotational angiography incidentally demonstrated a common origin of the AChA with the PComA. CONCLUSIONS: A rare case of a shared-origin AChA and PComA is reported for angiographic illustration. The radiologic findings, embryology behind the development of the AChA, and neurosurgical and neurovascular relevance of this variant are discussed. The importance of recognizing the origin of the AChA is emphasized.