Newsletter 2016.2 Index
| Theme : "The Conference of Fluid Engineering Division" 
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Research for Cerebral Aneurysm Recanalization After Coil Embolization Using CFD
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Abstract
Subarachnoid hemorrhage is the leading  cause of death or severe disability, and cerebral aneurysm is a major cause for  the disease because of its rupture. Thus, the patients who have unruptured  aneurysms need to be obliterated them by clipping or endovascular treatment. 
            Coil embolization has been one of the most  popular methods to treat an unruptured saccular cerebral aneurysm because of  its minimal invasiveness. In this method, thin biocompatible metal wires are  inserted into an aneurysm by a catheter and the dome region is filled with this  medical devices. Leading a thrombus in the aneurysm with the inserted coils,  blood flowing into it is prevented and the risk of the aneurysm rupture will be  decreased. However, recurrence of aneurysms after coil embolization remains as  a major problem. This phenomenon means a re-inflow of blood into the aneurysm  because of coil compaction, which means the coil is literally compacted into  the aneurysm physically, or re-growth of the aneurysm. Clinical reports showed  that around 10% - 25% aneurysms with coil were recanalized. Unfortunately, the  risk assessment protocol for such procedure has not been established yet, and  the mechanism has not been understood clearly either.
          We characterize the hemodynamics of  aneurysms before and after first embolization cases using CFD. In this study,  the patient specific models of arteries and embolized coil from  three-dimensional digital subtraction angiography (3D-DSA) data are used. We  process hemodynamic and morphological parameters, and examined the difference  of them between recanalized cases and stable cases statistically to investigate  the occurrence mechanism of the aneurysm recanalization. The results indicate  that some hemodynamic and morphological parameters may be factors for recanalization.  From the result, we may propose the patient-specific indicator, volume  embolization ratio (VER), to prevent the prospective recurrence of aneurysms.
Key words
Figures

          Fig. 1  Saccular Aneurysm

  Fig.  2 Illustration and Angiographic images of recanalized  aneurysm 
  Fig. 3  Analysis Flow

  Fig. 4  Result of Recanalized Case

 
    