The surgical approach may be difficult because of the complex arterial relationship, perforator preservation, frequent association between aneurysms and AcoA anomaly, and the potential for cognitive dysfunction. Especially, the high positioned ACoA aneurysms or posterior superior directed AcoA aneurysms have an additional complicating features. They need more brain retraction or their neck is usually associated intimately with the hypothalamic or infundibular perforators and frequently, one or both A2 segments densely adherent to the body of the aneurysm 1) 2) 3) 4).
A pterional approach is the most common for aneurysm surgery, not only for anterior circulation aneurysms but also for basilar tip aneurysms. There are some variations for the interhemispheric approach including bifrontal, unifrontal, basal interhemispheric, and transcrista galli interfalcine approaches.