Endovascular strategies for vertebrobasilar dissecting aneurysms.

BACKGROUND AND PURPOSE Dissecting vertebrobasilar aneurysms are challenging to treat, and standard treatment modalities remain controversial. We retrospectively evaluated our experience using endovascular techniques to treat these aneurysms. MATERIALS AND METHODS From February 1997 to December 2007, 42 patients with intradural vertebrobasilar dissecting aneurysms underwent endovascular treatment. Twenty-nine patients had ruptured aneurysms, and 13 patients had unruptured dissecting aneurysms. The endovascular modalities for vertebrobasilar dissecting aneurysms were the following: 1) trapping (n = 30), 2) proximal occlusion (n = 3), 3) stent with coil (n = 6), and 4) stent alone (n = 3). RESULTS Seventeen of the 29 patients with ruptured vertebrobasilar dissecting aneurysms had successful outcomes without procedural complications following endovascular treatment. Procedure-related complications were the following: 1) rebleeding (n = 3), 2) posterior inferior cerebellar artery (PICA) territory infarction (n = 6), 3) brain stem infarction (n = 2), and 4) thromboembolism-related multiple infarctions (n = 1). Clinical outcomes were favorable in 32 patients (76.1%). There were 3 (7.1%) procedure-related mortalities due to rebleeding, and 1 (2.4%) non-procedure-related mortality due to pneumonia sepsis. All 13 patients with unruptured vertebrobasilar dissecting aneurysms had favorable clinical and radiologic outcomes without procedure-related complications. CONCLUSIONS Endovascular procedures for treatment of unruptured symptomatic dissecting aneurysms resulted in favorable outcomes. Ruptured vertebrobasilar dissecting aneurysms are associated with a high risk of periprocedural complications. Risks can be managed by using appropriate endovascular techniques according to aneurysm location, configuration, and relationship with the PICA.