Technique and device specific diffusion-weighted imaging detected ischemic lesions and occlusion outcomes in endovascular treatment of unruptured aneurysms

BACKGROUND: This prospective study evaluated 6-month aneurysm occlusion and diffusion-weighted imaging (DWI) lesion rates following endovascular treatment of unruptured intracranial aneurysms (UIAs). We hypothesized that complex techniques would yield better occlusion but more DWI lesions. METHODS: We conducted a single-center, prospective cohort study of consecutive patients treated for UIAs with 6-month angiographic follow-up. Treatment technique was categorized as complex (flow diversion, stent-assisted coiling [SAC], or balloon-assisted coiling [BAC]) or non-complex (simple coiling, Trenza-assisted coiling, or intrasaccular device placement). Aneurysm morphology was classified as complex and non-complex according to a Delphi statement. Primary outcomes were adequate occlusion (complete or neck residual) at 6 months and postprocedural DWI lesions, assessed by MRI. RESULTS: In 113 patients, complex treatment was used in 96% (n = 25/26) of complex aneurysms, whereas 57% (n = 53/93) of non-complex aneurysms underwent non-complex treatment (p < 0.001). There were no differences in occlusion rates (90% vs. 81%, p = 0.181) or DWI rates (56% vs. 69%, p = 0.124) between non-complex and complex treatments. Aneurysm complexity associated with lower occlusion rates (67% vs. 90%, p = 0.012) but not with DWI lesion rates (58% vs. 65%, p = 0.524). Notably, individual techniques demonstrated greater variation in DWI rates (42-100%) than in occlusion rates (70-100%). CONCLUSION: Occlusion rates at 6 months were high across techniques, but DWI lesion rates varied substantially between individual techniques. The ischemic burden appears to be driven by the specific endovascular technique rather than by broad categorizations of procedural complexity. Thus, careful technique selection is critical to minimize ischemic risk while appropriately addressing aneurysm complexity.