Analysis of the CLARITY series shows no difference between Guglielmi Detachable Coils and Matrix coils for ruptured aneurysms


Laurent Pierot, Reims, France, and colleagues, on behalf of the CLARITY investigators, reported that midterm anatomic results and evolution of aneurysm occlusion were not different in patients with ruptured aneurysms who were treated with Guglielmi Detachable Coils (GDC) when compared to those treated with Matrix coils. 

The study was published in the American Journal of Neuroradiology (AJNR) in March. Pierot told NeuroNews that this was the first study comparing patients with ruptured aneurysms treated with GDC or Matrix coils. “Mid-term anatomical occlusion and evolution of aneurysm occlusion are similar whatever the type of coils used,” he said.

Matrix coils have been developed to prevent aneurysm recanalisation, the investigators have written. Their study focused on the midterm anatomic results in a prospective multicentre, consecutive series including patients treated with GDC or Matrix coils for ruptured aneurysms.

The investigators noted that 517 patients with ruptured aneurysms were treated with either GDC (276 patients) or Matrix coils (241 patients). The team evaluated postoperative and mid-term anatomic results were anonymously and independently using the Modified Montreal Scale (complete occlusion, neck remnant, and aneurysm remnant).

The researchers found in the mid-term follow-up (mean, 16.7 months in the GDC group and 15.4 months in the Matrix group) that complete occlusion was reported in 95/276 aneurysms (34.4%) in the GDC group and 80/241 (33.2%) in the Matrix group.

With regard to neck remnant, investigators reported that in the GDC group, this was 127/276 (46%) and in the Matrix group, it was 118/241 (49%). In the GDC group, there was aneurysm remnant in 54/276 (19.6%) in the GDC group and 43/241 (17.8%) in the Matrix group.

Similarly, in terms of evolution of aneurysm occlusion, there was improvement in 35/272 aneurysms (12.9%) in the GDC group and 27/239 (11.3%) in the Matrix group. The aneurysms were in a stable situation in 98/272 (36%) of the GDC group and 97/239 (40.6%) in the Matrix group. The aneurysms worsened in 139/272 (51.1%) in the GDC group and 115/239 (48.1%) in the Matrix group. A total of 32/517 patients were re-treated during the follow-up period: 9/276 (3.3%) in the GDC group and 23/241 (9.5%) in the Matrix group (p=0 .003), the investigators said.

“According to the results of CLARITY, the treatment of ruptured aneurysms with Matrix coils is not recommended,” Pierot told NeuroNews.