Comparison of two techniques of endovascular coil modeling in cerebral aneurysms using CFD

Coiling is the most common endovascular therapy for cerebral aneurysms. In this work, the influence of coil embolization on intra-aneurysmal hemodynamics was studied using two techniques for modeling coils. The first technique represented each coil explicitly and the second one approximated the coil structure with a porous medium. CFD simulations of pre- and post-treatment conditions were compared for one anatomically realistic cerebral aneurysm model. We observed a larger decrease in time- and space-averaged velocity in the aneurysm with the explicit model (92.3%) than with the porous medium model (71.4%). The difference between the two techniques was also demonstrated using virtual contrast injection. Whereas with the explicit model there was a large decrease in the amount of contrast entering the aneurysm and an increase in washout time, these phenomena were not observed with the porous medium model.