Background Flow diverters (FDs) are increasingly used for bifurcation aneurysms. Failure of aneurysm occlusion may be caused by residual flow maintaining patency of the jailed branch along with the aneurysm. Our aim was to test whether endovascular occlusion of the jailed branch could improve efficacy of flow diversion of bifurcation aneurysms.
Materials and methods Sixteen wide-necked lingual–carotid artery bifurcation aneurysms were created in eight canines. Patent aneurysms were randomly allocated 4 weeks later to flow diversion combined with jailed branch occlusion using coils and/or Onyx (n=6) or flow diversion alone (n=8). Angiographic results of aneurysm occlusion at 3 months were scored using an ordinal scale. Pathology specimens were photographed and neointimal coverage estimated using a semiquantitative scoring system.
Results Fourteen aneurysms were patent at 1 month. FD deployment was successful in all cases but, at 3-month follow-up, three devices had prolapsed into the aneurysm. None of the bifurcation aneurysms treated with FD alone were occluded at 3 months. Endovascular branch occlusion combined with flow diversion significantly improved aneurysm occlusion rates compared with flow diversion alone (median angiographic scores 2 vs 0: p=0.0137). Flow-limiting parent vessel stenosis was not observed in any arteries. Devices were covered with thick neointima in most cases, but patent aneurysms were associated with leaks or holes in the neointima covering the aneurysm neck.
Conclusions Treatment failures following flow diversion of bifurcation aneurysms can be caused by persistent flow to the jailed branch. Branch occlusion combined with flow diversion may improve angiographic occlusion scores of a canine bifurcation aneurysm model.
- Flow Diverter
Statistics from Altmetric.com
Contributors JR and TED designed the experiments; JR, TED, IS, RF and JCG performed the experiments; JR, TED, IS, RF, JCG and GG analyzed and processed the data and drafted the manuscript. All authors revised the draft manuscript and gave final approval of the version to be published. JR and TED agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.
Funding This work was supported by a research grant delivered by the Heart and Stroke Foundation of Alberta (grant number GIA-0200296) to TED. RF is the recipient of a research scholarship delivered by the Fondation pour la Recherche Médicale (FRM), Paris, France (grant number DEA20140630151).
Competing interests None declared.
Provenance and peer review Not commissioned; externally peer reviewed.
Data sharing statement Unpublished/raw data may be available to academic researchers on a per request basis to the corresponding author.
Animal studies Principles of laboratory animal care (NIH publication No 86-23, revised 1985) were followed, as well as the guidelines of the Canadian Council on Animal Care. The protocol for animal experimentation was approved by the Institutional Animal Care Committee of our institution (CIPA).
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.