Early experience with flow diverting endoluminal stents for the treatment of intracranial aneurysms

We aimed to identify the initial preliminary experience with flow diverting stents (FDS) for the treatment of intracranial aneurysms (IA). A PubMed search was performed to identify studies reporting patients treated with FDS. Selection was made for studies that provided either immediate or short term follow-up data. For each study, the number of patients and IA were identified. Details regarding the aneurysm itself were recorded; such as aneurysm morphology (saccular or fusiform), location, and rupture status. The primary treatment modality and the number of stents used to treat each aneurysm was recorded along with the antiplatelet regimen used. Outcomes such as aneurysm occlusion and complications, including stroke, in-stent thrombosis and stenosis, and death were identified. The average length of follow-up was calculated in weeks. A total of 10 manuscripts reporting 206 IA in 190 patients were identified in the literature. Occlusion rates were variably reported, ranging from 58% to 94% in the larger series. Major complications of treatment included stroke (6.0%), in-stent thrombosis and stenosis (4.9%), and death (3.3%). A phenomenon of delayed aneurysm rupture was also identified. We concluded that flow diverting stents have proven effective in a variety of scenarios. The major complications with FDS have related to perforator artery stroke, aneurysm re-rupture, and in-stent stenosis and thrombosis. Long-term efficacy, optimal antithrombotic agent regimen, and perforator stroke risk are yet to be determined.