“…This information will be useful for the surgeon, particularly in extra-and intracranial bypass operations, in determining the surgeon's approach and identifying the branch more suitable for bypass. 6,18,39 Middle cerebral artery aneurysms constitute a substantial percentage of cranial aneurysms. 1,2,13,23,24,26,33,38 Considering that these aneurysms particularly occur at the bifurcation site, the importance of thorough knowl-edge regarding the arterial anatomy, trunk structures, cortical branches originating from the separation point, and their interrelations in this region is obvious.…”