Decision-making for endovascular treatment of a fusiform basilar trunk artery aneurysm with visualization of chronological blood mass distribution using computational fluid dynamics.

Fusiform basilar trunk artery aneurysms are rare lesions, to which stent-assisted coil embolization or flow diversion have been generally applied. When a stent is placed from the distal basilar artery or the posterior cerebral artery to the vertebral artery (VA) through a fusiform basilar artery aneurysm, the side of the VA may be determined according to its size, shape, accessibility and aneurysm projection. In the present report, we constructed stent-placement models from the distal basilar artery to either VA across the aneurysm, and investigated blood mass distribution using computational fluid dynamics. The results revealed more stagnated blood flow in the aneurysm after stenting to the left VA. According to the simulation, stent-assisted coil embolization of the aneurysm was performed, resulting in sufficient obliteration. This visualization technique could be useful for decision-making for the treatment of complicated aneurysms and has a wide range of potential applications.