HEMODYNAMIC CHANGES IN PATIENT-SPECIFIC MODELS OF CEREBRAL ANEURYSMS WITH AND WITHOUT VIRTUAL FLOW DIVERTERS INVESTIGATED WITH A DEDICATED CFD RESEARCH PROTOTYPE

摘要

Computational fluid dynamics (CFD) techniques have been pioneered to calculate wall shear stresses, dynamics pressures and other hemodynamics parameters for identifying additional risk factors for cerebral aneurysm rupture.In recent years, an extension to endovascular treatment of cerebral aneurysms has become available where a stent with a dense mesh (flow diverter, FD) is placed across the aneurysm ostium anchored in the proximal and distal segments of the parent artery thereby diverting the majority of blood flow away from the aneurysm. Indications for FD are complex aneurysms (fusiform, large and giant, wide neck small aneurysms untreatable by conventional coiling) as well as recurrences. Clinical reports mainly of single center experience demonstrate successful application of this technique and larger trials are currently preformed to assess its efficacy.Potential complications include incomplete separation of the aneurysm from the circulation, i.e. the existence of a remnant inflow jet and, more importantly, later aneurysm hemorrhage. CFD has been employed to investigate hemodynamics after FD treatment. In that study, which investigated 3 aneurysms that ruptured after FD treatment and 4 which did not, adverse hemodynamic conditions included a pressure increase in the aneurysmal sac despite successful flow diversion. A better understanding of potential adverse hemodynamic changes prior to the actual treatment might therefore be of help to the interventionalist during treatment planning.