Anomalous origins of the calcarine and parieto-occipital arteries

Understanding cerebrovascular anatomy and its variations is of utmost importance in treating vascular malformations. The two patients presented here demonstrate yet to be reported anomalous origins of the cortical branches of the posterior cerebral artery. In one patient, fetal calcarine arteries were identified arising from the internal carotid arteries bilaterally with no calcarine branches arising from the posterior circulation and the basilar artery giving rise to terminal parieto-occipital arteries. Additionally, with vertebral artery injections, we found the dominant arterial supply to the right parieto-occipital artery arose from the right internal carotid artery and right posterior communicating artery and the dominant arterial supply to the left parieto-occipital artery arose from the right vertebral artery. A second patient demonstrated anomalous origins of the calcarine and parietal occipital branches from the supraclinoid left internal carotid artery. Understanding this complex cerebrovascular anatomy is important in the endovascular treatment of cerebrovascular aneurysms and malformations.

了解脑血管解剖结构及其变异在治疗血管畸形方面至关重要。这里介绍的两名患者展示了尚未被报道的大脑后动脉皮质支的异常起源。在一名患者中，发现双侧胎儿距状动脉起自颈内动脉，而后循环没有距状分支发出，且基底动脉发出顶枕终末动脉。此外，在椎动脉注射时，我们发现右侧顶枕动脉的主要供血动脉来自右侧颈内动脉和右侧后交通动脉，左侧顶枕动脉的主要供血动脉来自右侧椎动脉。第二名患者表现出距状动脉和顶枕支起自左侧颈内动脉床突上段的异常起源。了解这种复杂的脑血管解剖结构在脑血管动脉瘤和畸形的血管内治疗中非常重要。