Flow diversion of giant curved sidewall and bifurcation experimental aneurysms with very-low-porosity devices.
OBJECTIVE
Flow diverters (FDs) are increasingly used to treat difficult intracranial aneurysms. The objective of this study was to test whether treatment challenges posed by giant curved sidewall (cSW) and endwall bifurcation (EwB) aneurysms can be overcome with the use of very-low-porosity devices.


METHODS
Large and giant EwB (n = 12) and cSW aneurysms (n = 5) were constructed in 17 dogs. EwB aneurysms were treated with 48 (n = 4), 64 (n = 4), or two overlapping 64-wire low-porosity devices (n = 4), whereas all cSW aneurysms were treated with single 64-wire devices. Angiographic results were recorded immediately and at 12 weeks before euthanasia. Pathologic specimens were photographed and neointimal coverage of devices measured and scored.


RESULTS
By 12 weeks, 1 of 12 EwB and 1 of 5 cSW aneurysms were occluded. All other aneurysms were patent. Device-related arterial stenoses occurred in 13 of 17 animals, hemodynamically significant in two. All branches jailed by the FDs remained patent. There was a significant correlation between angiographic scores and the degree of neointima formation on the device (Rho = 0.527; P = 0.04). Failures of aneurysm occlusion could be explained by holes, sometimes barely visible, in the neointima that formed over FDs.


CONCLUSIONS
Low-porosity FDs fail to reliably occlude experimental giant EwB and cSW aneurysms.
University of Alberta Hospital, Mackenzie Health Sciences Centre, Division of Neurosurgery, Department of Surgery, Edmonton, Alberta, Canada.
Tim E
TE
Darsaut
CHRU Strasbourg, Service de Neuroradiologie, Strasbourg, France.
Fabrice
F
Bing
Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital Research Centre, Laboratory of Interventional Neuroradiology, Montreal, Quebec, Canada.
Alina
A
Makoyeva
Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital Research Centre, Laboratory of Interventional Neuroradiology, Montreal, Quebec, Canada.
Guylaine
G
Gevry
Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital Research Centre, Laboratory of Interventional Neuroradiology, Montreal, Quebec, Canada.
Igor
I
Salazkin
Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital, Department of Radiology, Montreal, Quebec, Canada; Centre Hospitalier de l'Université de Montréal, Notre-Dame Hospital Research Centre, Laboratory of Interventional Neuroradiology, Montreal, Quebec, Canada. Electronic address: jean.raymond@umontreal.ca.
Jean
J
Raymond
D000818:Animals; D002533:Cerebral Angiography; D003251:Constriction, Pathologic / Q000209:etiology; D004195:Disease Models, Animal; D004285:Dogs; D057510:Endovascular Procedures / Q000379:methods; D004867:Equipment Design; D006083:Graft Occlusion, Vascular; D002532:Intracranial Aneurysm / Q000601:surgery*; D016062:Porosity; D015607:Stents / Q000009:adverse effects
Animal model; Experimental aneurysm; Flow diverter; Giant aneurysm; Stent deformation