Recanalization after endovascular treatment of intracerebral aneurysms

The aim of this study was to evaluate the risks of endovascular therapy, aneurysm regrowth, recanalization and the need for reembolization.

A prospective analysis was performed on 211 aneurysms treated endovascularly from February 2000 to December 2003. Of these 211 aneurysms, 81 were asymptomatic and 130 were ruptured. The risks of endovascular therapy, aneurysm regrowth, recanalization and the need for reembolization were evaluated.

The mean observation time was 10 months (ranging from 178 to 830 days). Complete occlusion (100%) in the initial intervention was achieved in 171 of 201 aneurysms (85%), 80-95% occlusion in 24 aneurysms (12%), and <80% occlusion in 6 aneurysms (3%). Recanalization had occurred at the first follow-up in 34 of all 153 aneurysms reassessed (22.2%). Of 133 aneurysms with initial 100% occlusion, 107 (80.4%) remained completely occluded, 17 (12.7%) showed recanalization, and 9 (6.7%) showed neck regrowth. Among those with 80-95% occlusion, 20 were reassessed, and of these 2 showed spontaneous occlusion, 10 (50%) still showed the initial neck, and 8 (40%) showed increased recanalization. One aneurysm which initially showed <80% occlusion remained unchanged, and another showed showed recanalization. Of the 153 aneurysms, 12 (7.8%) were recoiled, 2 initially <80% occluded, 7 initially 80-95% occluded and 3 initially totally occluded.

In spite of low morbidity and mortality, one in four aneurysms will show recurrence. The initial degree of occlusion seems to have an influence on the likelihood of recanalization.