Long-term outcomes of flow diversion for unruptured intracranial aneurysms: a systematic review and meta-analysis

Abstract

BackgroundFlow diverters have been widely used in clinical practice for more than a decade. However, most outcome data are limited to 1 year timepoints. This study aims to offer meta-analysis data on long-term (>1 year) safety and effectiveness results for patients with aneurysms treated with flow diverters.MethodsPubMed, Web of Science, Embase, and SCOPUS were searched up to February 24, 2022 using the AutoLit platform. We included primary studies assessing the long-term outcomes for flow diverter devices to manage unruptured internal carotid artery aneurysms with a follow-up period of >1 year. The meta-analysis was carried out using Comprehensive Meta-Analysis software (CMA).ResultsEleven studies were included in the meta-analysis. The pooled occlusion rates after flow diversion treatment for unruptured intracranial brain aneurysms were 77%, 87.4%, 84.5%, 89.4%, 96% for 1 year, 1–2 years, 2 years, 3 years, and 5 years follow-up, respectively. The in-stent stenosis rate was 4.8% and the retreatment rate for the long-term follow-up period was 5%. No delayed rupture of the aneurysm was reported, and there was one case of delayed ischemic stroke. The sensitivity analysis of the prospective studies showed a complete occlusion rate of 83.5% and 85.2% for 1 and 3 years of follow-up, respectively.ConclusionFlow diverters are safe and effective in short- and long-term follow-up and rarely cause serious delayed side effects.

In reply

“…They criticise that this recommendation is based on what they describe as 'a single small prospective study' and 'small exploratory study', 3 and state that 'in the meantime a plethora of retrospective and prospective controlled data is available demonstrating overwhelming safety and efficacy of flow diverting stents', referring to the review mentioned above. 2 Since we had not found any controlled studies in our systematic review of the literature, we read with interest the studies referenced in this systematic review. To our disappointment none of the 11 studies included in the review had a control group.…”

“…We are delighted to read that the ESO guidelines on management of unruptured intracranial aneurysms have attracted attention, 1 and we thank Drs Bendszus and Möhlenbruch for drawing our attention to a systematic review of the literature that has become available after publication of the guidelines. 2 Drs Bendszus and Möhlenbruch challenge our suggestion to use flow diverting stents as a treatment option only if no other endovascular or microsurgical options are available to occlude the aneurysm at a risk lower than the expected 5-year risk of rupture and if the risk of rupture outweighs the risk of treatment with flow diverting stents. They criticise that this recommendation is based on what they describe as 'a single small prospective study' and 'small exploratory study', 3 and state that 'in the meantime a plethora of retrospective and prospective controlled data is available demonstrating overwhelming safety and efficacy of flow diverting stents', referring to the review mentioned above.…”

“…We are delighted to read that the ESO guidelines on management of unruptured intracranial aneurysms have attracted attention, 1 and we thank Drs Bendszus and Möhlenbruch for drawing our attention to a systematic review of the literature that has become available after publication of the guidelines. 2…”

Letter: Commentary: The Pennsylvania Postmarket Multicenter Experience With Flow Redirection Endoluminal Device

“…Multiple questions currently remain in the FD literature; these include the long-term efficacy of the different devices and whether there are any safety/efficacy differences between these devices. A recent systematic review reported a pooled 5-year complete occlusion rate of 96% with most of the literature studies using PED 14 ; however, the analysis did not account for the different FD devices nor particular aneurysmal location, and further studies on this remain warranted. Moreover, limited data are currently known regarding which aneurysm type might be suited for each of those devices and head-to-head comparative performance data of the different devices in certain aneurysms location, for which prospective trials would be needed.…”

Flow diverter stent treatment for unruptured supraclinoid segment internal carotid artery aneurysms: a Turkish multicenter study

“…FD stents were initially designed and licensed for large, intracranial, and unruptured ICA aneurysms. 5 To this end, FDs have also been combined with coiling for ruptured or unruptured aneurysms [7][8][9] and blister-like/dissecting aneurysms. 10 Although van Rooij et al 11 considered EVT dangerous and not yet an alternative for unruptured ICA aneurysms in 2013, EVT is now preferred as first-line treatment in many centers.…”