[Examination of factors useful for choosing a method to assist coil embolization of unruptured cerebral aneurysm].

BACKGROUND: In coil embolization of neurovascular aneurysms, we have noted that few wide-necked unruptured aneurysms are successfully embolized. This prompted us to search for useful factors to assist the choice of methods of coil embolization. METHOD: We first measured aneurysm size and volume using auto measurement (NVvol) and VER (NVver). Second, we calculated the volume (NVapp) and VER (NVapp) using approximation expressions. Third, we measured the end-on view neck angle using a 3 dimensional digital subtraction angiography (3D-DSA) image. RESULTS: NVvol and NVapp were correlated (y=0.87x). NVvol VER and NVapp VER approached 24% in 41 clinical cases. The dome/neck ratio averaged 1.15. Length of neck and the end-on view neck angle were significantly different between the stent-assisted group and the balloon-assisted group. NVvol and NVapp showed a good correlation with basic examination results in 41 clinical cases. CONCLUSION: The end-on view neck angle is significantly different. This boundary neck angle was 100° for the two groups. The end on-view neck angle is thus a useful factor for deciding medical treatment strategy.

[Importance of three dimensional-fusion image after stent-assisted coil embolization of unruptured aneurysm].

PURPOSE: We made the fusion image of both stent and platinum coil after embolization of an unruptured aneurysm. METHOD: After scanning with cone beam computed tomography, we made three dimensional (3D) images of stent and coil and fused them. CONCLUSION: We can evaluate unruptured aneurysm after embolization by using a fusion image. 3D-fusion image is useful on clinical cases.

[Importance of an automatic measurement base on the first coil diameter in regard to coil embolization of a cerebral aneurysm].

We compared the accuracy in evaluating an unrapture aneurysm between NV and 3D-DSA. In vitro, we evaluated the accuracy in calculating the volume of the Aneurysm model. We compared the diameter of the first coil and estimated the diameter of the Aneurysm. The Aneurysm size calculated by NV resembled the first coil more than the size measured by 3D-DSA. In clinical cases, the measurement of NV is objective; the measurement of 3D-DSA, however, is subjective by person. NV has an automatic measurement that is useful for clinical cases.