Introduction: Endovascular coil embolization has become increasingly utilized for the treatment of intracranial aneurysms. Still, controversy exists regarding the long-term durability of this technique. The objective of this study is to assess the effect of aneurysm configuration on the durability of coil embolization.

Methods: Retrospective analysis of all patients treated by coil embolization from August 2002 through September 2008 who underwent follow up angiography at least 3 weeks after embolization. Demographic data and aneurysm characteristics, including configuration, were recorded. Two endovascular specialists assessed aneurysm occlusion on initial and follow-up angiography, and graded using the Raymond Scale (RS). The influence of patient data and aneurysm configuration on the initial obliteration and occurrence of recanalization were examined.

Results: The most frequent aneurysm configuration was the regular spherical (RSP), while the least common was fusiform. There were no differences in the distribution of aneurysm configuration with regard to age and sex. Based on the initial occlusion, RSP configuration was found to have the highest RS 1 rates (66.7%). Mushroom configurations were found to have the lowest rates (0%). Aneurysms that were initially RS 1 were more stable at follow-up than those in which only RS 2 or RS 3 occlusion could be achieved. As such, the initial RS did seem to influence durability. RSP aneurysms were most common and largely were unchanged on follow-up.

Conclusions: Aneurysm configuration is an interesting factor that should be considered in future studies exploring the natural history of endovascular treatment of aneurysms as well as developing more durable endovascular tools and techniques.

Patient Care: Assessing the effect of aneurysm configuration on the durability of coil embolization enables the development of more durable endovascular tools and techniques, which ultimately will improve patient outcomes.

Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the importance of endovascular coil embolization, 2) Discuss, in small groups, the effects of aneurysm configuation on the durability of coil embolization, 3) Identify an effective endovascular treatment for intracranial aneurysms.

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