Comparative Analysis of Long-Term Effect of Stent-Assisted Coiling in Unruptured Sidewall-Type and Terminal-Type Aneurysms.

Background: Stent-assisted coiling is recognized as effective to induce progressive occlusion and prevent recurrence of aneurysm. The long-term effects of stent-assisted coiling of sidewall-type and terminal-type aneurysms were comparatively analyzed focusing on the different hemodynamic characteristics.

Methods: Retrospective analysis included a total of 120 unruptured aneurysms in 116 consecutive patients who underwent stent-assisted coiling and completed 2-year follow-up. The stent systems, baseline characteristics, and postcoiling occlusion status of sidewall-type and terminal-type aneurysms were assessed.

Results: Sidewall-type aneurysms had a significantly larger dome size (P = 0.02) and greater diameter of the parent vessel (P < 0.001) than terminal-type aneurysms. Initial occlusion status of the aneurysms was significantly maintained for 2 years in both sidewall-type and terminal-type aneurysms as follows: sidewall-type aneurysms showed that complete occlusion (CO), neck remnants (NRs), and body filling (BF) immediately posttreatment were significantly correlated with CO (P < 0.05), NRs (P < 0.01), and BF (P < 0.05) at 2-year follow-up, respectively, and terminal-type aneurysms showed that CO, NRs, and BF immediately posttreatment were significantly correlated with CO (P < 0.05), NRs (P < 0.05), and BF (P < 0.05) at 2-year follow-up, respectively. In addition, sidewall-type aneurysms with CO immediately posttreatment were significantly correlated with non-NRs (P < 0.01) and non-BF (P < 0.01) at 2-year follow-up.

Conclusions: Stent-assisted coiling allows higher coil packing for sidewall-type aneurysms, but the indication should be carefully considered for terminal-type aneurysms.