Association between an aneurysm of the anterior inferior cerebral artery and an arteriovenous malformation fed by the same artery.

An unusual case of distal aneurysm of the anterior inferior cerebellar artery (AICA) associated with a cerebellar arteriovenous malformation in a 35 year-old woman is reported. The clinical presentation was a subarachnoid hemorrhage, that is the sudden onset of headache while she was driving her car. In the following days the patient experienced a cerebellopontine angle syndrome: unsteadiness, tinnitus and hearing loss in her left ear, along with drop episodes.

Surgical treatment of a rare congenital anomaly of the vertebral artery: case report and review of the literature.

A case of an abnormal loop of the vertebral artery compressing both the cervicomedullary junction and the accessory nerve is reported. The embryological development of the vertebrobasilar system may explain this anatomical anomaly. The possibility of an abnormal location of the vertebral artery may complicate the lateral C1-C2 puncture for myelography.

Extracerebral course of the perforating branches of the anterior communicating artery: microsurgical anatomical study.

Damage to the perforating branches arising from the anterior communicating artery, because of their blood supply to the septal nuclei and anterior hypothalamus, explains the memory impairment and the electrolyte disturbances that often follow the surgery of aneurysms located in this part of the circle of Willis. The microsurgical anatomy of these branches was studied on 60 fixed human brains, with special attention to their number, caliber, and vascular territory. The direction of the branches was evaluated, measuring the angle formed by them with the postcommunicating segment of the anterior cerebral artery.

Anomalies of the P1 segment of the posterior cerebral artery: early bifurcation or duplication, fenestration, common trunk with the superior cerebellar artery.

In a series of anatomical dissections on 100 fixed human brains, 3% of anomalies of the precommunicating segment of the posterior cerebral artery (P1) were found, among which a case of duplication of the P1 segment. This finding is very unusual and it is much rarer than the many other anatomical patterns reported in the circle of Willis. It is to be considered a very early bifurcation, as reported at the middle cerebral artery level.

Microsurgical anatomy of the cisternal course of the perforating branches of the posterior communicating artery.

Both the perforating branches--especially the extracerebral segments--and the arachnoidal anatomy at the level of the posterior communicating artery were studied in 60 human brains previously fixed in formalin. The close relationships between this artery and the oculomotor nerve are described, and it is noted that each of them is enclosed in its own arachnoidal compartment, which in the case of the posterior communicating artery is to be distinguished from the interpeduncular cistern. The latter cistern was found to contain only the terminal segments of the posterior communicating artery.