Discussion
aneurysm, Intraoperative aneurysm rupture, aneurysms, Numen, small aneurysms, thrombus, saccular aneurysms, unruptured aneurysms, intracranial aneurysms
ANEURYSM, COMPLICATION, ANEURYSMS, THROMBUS, SACCULAR ANEURYSMS, EVENTS, COMPLICATIONS, INTRACRANIAL ANEURYSMS
Although several studies have been conducted to evaluate the safety and efficacy of the endovascular treatment of small intracranial aneurysms, randomized trials are still lacking. We extracted data from the CATCH trial and found that endovascular coiling techniques for treating small intracranial aneurysms are safe and feasible. Our results showed high success rates and complete occlusion immediately after endovascular surgery and during follow-up. According to a meta-analysis by Yamaki et al., technical success was achieved in 92% of patients, and 7% of aneurysms retreated [Intraoperative aneurysm rupture is a severe complication in the endovascular treatment of small aneurysms. The small size of the aneurysm sac limits the movement of the microcatheter [This study showed that the Numen coil was non-inferior to the Axium coil in treating small intracranial aneurysms. Unlike Axium coils, there are two types of three-dimensional (3D) coil shapes for Numen coils: 3/4 loops and 1/2 loops. The 3D coil with 3/4 loops is fabricated by a series of Ω-shaped loops, which provides a stable framing in the aneurysm sac. And the 3D coil with 1/2 loops is formed by a series of Ω-shaped and S-shaped loops incorporated for dense filling and safe finishing. The advantage of Numen coils includes: firstly, the anti-unwinding design improves its softness; secondly, the half size standard makes the selection more accurate; thirdly, the shorter caudal segment in length enhances the stability of the microcatheter. The coil packing density was suggested to be reduced, allowing slow thrombus formation in the sac [Although an additional assist device can facilitate coil packing, it may increase the incidence of complications, especially ischemic events [When dealing with small unruptured aneurysms, the natural history of these aneurysms should be considered [Only small saccular aneurysms were involved in this study, so the results only represent the treatment of one particular type of aneurysm. Well-controlled studies in the future were needed for validation. In addition, although we included aneurysms in the posterior circulation, there were only two cases of such aneurysms. Studies on using these techniques in treating aneurysms in the posterior circulation should be performed.