An anatomical diagram illustrating the arterial supply of the brain from an inferior (basal) perspective, specifically highlighting the Circle of Willis and its contributing vessels. The diagram shows the bilateral internal carotid arteries branching into the middle cerebral (MCA) and ophthalmic arteries. Centrally, the anterior cerebral arteries (ACA) are seen originating and coursing medially into the longitudinal fissure, connected by the anterior communicating artery (ACoA). The posterior circulation is depicted with the vertebral arteries merging into the basilar artery, which subsequently divides into the posterior cerebral arteries (PCA). Posterior communicating arteries (PCoA) are shown forming the critical anastomotic link between the internal carotid and posterior cerebral systems. The diagram is superimposed on the ventral surface of the brain, demonstrating the spatial relationship of these vessels to the frontal, temporal, and occipital lobes, as well as the cerebellum and brainstem. This illustration is an educational resource for understanding neurovascular anatomy and the territories susceptible to ischemic stroke.

This medical visual content consists of an anatomical diagram (a) and a corresponding clinical photograph of a cadaveric dissection (b) illustrating neurovascular anatomy. The focus is on the Circle of Willis, specifically demonstrating a congenital vascular variation known as aplasia of the A1 segment of the anterior cerebral artery (ACA). In both panels, a yellow dotted circle highlights the area where the right A1 segment should connect the internal carotid artery to the anterior communicating artery (ACoA). The absence of this segment results in an incomplete Circle of Willis, which has clinical significance for collateral cerebral blood flow. The diagram (a) clearly depicts the major components of the cerebral arterial circle, including the basilar artery, posterior cerebral arteries, internal carotid arteries, and the intact left A1 and A2 segments. The clinical photograph (b) provides a real-world view of the same anatomical deficiency at the base of the brain. This material is designed for advanced medical education in neuroanatomy and radiology, emphasizing common vascular anomalies.

This medical figure consists of an anatomical diagram (a) and a matching intraoperative/cadaveric photograph (b) illustrating an anatomical variant in the posterior Circle of Willis. The visual focus is the 'intermediate communicating artery' (ICoA) on the right side. In the diagram, the right posterior cerebral artery (PCA) is shown with dual pre-communicating origins: a carotid origin segment (PCA-P1c) and a basilar origin segment (PCA-P1b), linked by the right ICoA (indicated by arrows). The left side shows a conventional posterior communicating artery (PCoA) connecting the internal carotid artery (1) to the PCA. Other labeled structures include the basilar artery (6), internal carotid arteries (1, 2), and the post-communicating PCA segments (P2). The clinical photograph (b) provides a real-world correlate of this vascular configuration on the basal surface of the brain, highlighting the small caliber and anatomical path of the accessory ICoA. This material is designed for advanced neuroanatomical education, demonstrating rare vascular complexities and variations in cerebral blood supply.

Educational medical infographic containing three panels illustrating cerebral neurovasculature and acute ischemic stroke pathophysiology. The first panel, 'Cerebral Circulation', features a detailed anatomical diagram of the Circle of Willis, labeling the vertebral arteries, basilar artery, and its bifurcation into the posterior cerebral arteries (PCA). It further illustrates the internal carotid arteries, middle cerebral arteries (MCA), and the anterior cerebral arteries (ACA) connected by the anterior communicating artery. The second panel, 'Graphical representation of Acute Ischaemic Stroke', depicts a sagittal view of the brain showing an arterial blockage. It differentiates between the 'ischemic core' (irreversible damage) and the surrounding 'penumbra' (reversible/salvageable tissue). The third panel, 'Cerebral Artery Supply Zones', is a coronal brain cross-section color-coded to show perfusion territories, specifically highlighting regions supplied by the ACA (orange), MCA (green), PCA (blue), and anterior choroidal artery (red). This resource is designed for students learning about stroke mechanisms, vascular anatomy, and clinical neuro-perfusion.