[Contribution to the microanatomy of the proximal part of the arteria centralis longa (Heubner's artery)].

The anterior communicating artery complex is one of the most frequent intracranial aneurysm sites. Pterional craniotomy is the usual way to expose this region. While exposing of the aneurysmal dome, the posterior part of the gyrus rectus is frequently resected. In this stage of the procedure and later during clipping of the aneurysm, the surgeon's manipulation is closely related to the proximal part of the Heubner's artery. This vessel feeds important structures in the region of the basal ganglia. The anatomy of the Heubner's artery was described by many authors. However the intraoperative identification of this artery is still not clear. Therefore we performed detailed microanatomical investigation of the proximal part of the Heubner's artery in 40 brain hemispheres. It was found that during resection of the posterior part of the gyrus rectus two arteries are exposed. The recurrent Heubner's artery runs posteriorly to the gyrus rectus. The second artery runs on the medial and inferior surface of gyrus rectus supplying cerebral cortex. This artery frequently originates from the A1/A2 junction or the proximal part of the A2 segment of the anterior cerebral artery. Because of it, this cortical artery is difficult to distinguish from the recurrent Heubner's artery. This artery can branch out from the recurrent Heubner's artery or the frontopolar artery. In conclusion, the greatest probability of the injury to the recurrent Heubner's artery may occur during resection of the posterior part of the gyrus rectus.