Purpose To compare the quality of immediate anatomical results after the endovascular treatment of ruptured aneurysms using GDC and matrix coils in CLARITY series.

Methods Postoperative anatomical results were evaluated on digital subtraction angiography, anonymously and independently by two experienced neuroradiologists. Two different scales were used: the Montreal scale and a new scale specifically designed for the present study (CLARITY scale).

Results 401 aneurysms were treated using GDC coils and 373 using matrix coils. Immediate anatomical results (Montreal scale) were not significantly different with GDC or matrix coils. In the GDC group, the result was complete occlusion for 197 aneurysms (49.1%), neck remnant for 155 aneurysms (38.7%) and aneurysm remnant for 49 aneurysms (12.2%). In the matrix group, the result was complete occlusion for 168 aneurysms (44.9%), neck remnant for 171 aneurysms (45.7%) and aneurysm remnant for 35 aneurysms (9.4%). Similar results were obtained using the CLARITY scale.

The factors affecting the quality of aneurismal occlusion have been studied in both the GDC and matrix groups.

Conclusions The postoperative occlusion after endovascular treatment of ruptured aneurysms is satisfying with a high percentage of complete occlusion or neck remnant in both the GDC (87.8%) and matrix (90.6%) groups.