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

Abstract

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. 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. 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. 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.