CFDによる脳動脈瘤に対するフローダイバータステント留置術の評価

抄録

Cerebral aneurysm rupture is a fatal disease. While clipping has been widely recognized as a standard method, flow-diverting stent treatment is becoming common in US and EU. However, some clinical studies indicate that the stent placement works negatively, particularly in large aneurysm cases. In this study, therefore, we perform direct numerical simulations for spherical aneurysm models to investigate the flow characteristics in several types of aneurysm. The diameters of the aneurysm models are set to D=8mm and D=12mm. A flow diverter stent based on the pipeline stent is installed to cover the neck of the aneurysm. The results show that the flow pattern drastically changes by the stent installation. In the case of D=8mm, the flow direction in the aneurysm changes from counter-clockwise to clockwise. On the other hand, in the case of D=12mm, while the pattern changes as in the case of 8mm aneurysm at the beat peak, it becomes clockwise in the diastole phase. The peak pressure is slightly decreased by the stent placement in the case of D=8mm whereas it is increased in the case of D=12mm.