Relationship between aneurysm occlusion and flow diverting device oversizing in a rabbit model.
OBJECTIVE
Implanted, actual flow diverter pore density is thought to be strongly influenced by proper matching between the device size and parent artery diameter. The objective of this study was to characterize the correlation between device sizing, metal coverage, and the resultant occlusion of aneurysms following flow diverter treatment in a rabbit model.


METHODS
Rabbit saccular aneurysms were treated with flow diverters (iso-sized to proximal parent artery, 0.5 mm oversized, or 1.0 mm oversized, respectively, n=6 for each group). Eight weeks after implantation, the angiographic degree of aneurysm occlusion was graded (complete, near-complete, or incomplete). The ostium of the explanted aneurysm covered with the flow diverter struts was photographed. Based on gross anatomic findings, the metal coverage and pore density at the ostium of the aneurysm were calculated and correlated with the degree of aneurysm occlusion.


RESULTS
Angiographic results showed there were no statistically significant differences in aneurysm geometry and occlusion among groups. The mean parent artery diameter to flow diverter diameter ratio was higher in the 1.0 mm oversized group than in the other groups. Neither the percentage metal coverage nor the pore density showed statistically significant differences among groups. Aneurysm occlusion was inversely correlated with the ostium diameter, irrespective of the size of the device implanted.


CONCLUSIONS
Device sizing alone does not predict resultant pore density or metal coverage following flow diverter implantation in the rabbit aneurysm model. Aneurysm occlusion was not impacted by either metal coverage or pore density, but was inversely correlated with the diameter of the ostium.
Neuroradiology Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA.
Simona
S
Hodis
Neuroradiology Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA.
Yong-Hong
YH
Ding
Neuroradiology Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA.
Daying
D
Dai
Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota, USA.
Ravi
R
Lingineni
Center for Computational Fluid Dynamics, College of Sciences, George Mason University, Fairfax, Virginia, USA.
Fernando
http://orcid.org/0000-0003-1907-3739
F
Mut
Center for Computational Fluid Dynamics, College of Sciences, George Mason University, Fairfax, Virginia, USA.
Juan
J
Cebral
Neuroradiology Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA.
David
D
Kallmes
Neuroradiology Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA.
Ramanathan
R
Kadirvel
D000818:Animals; D001807:Blood Vessel Prosthesis / Q000592:standards*; D019917:Blood Vessel Prosthesis Implantation; D002560:Cerebrovascular Circulation / Q000502:physiology*; D004195:Disease Models, Animal; D057510:Endovascular Procedures / Q000295:instrumentation* / Q000379:methods; D002532:Intracranial Aneurysm / Q000628:therapy*; D011817:Rabbits
Aneurysm; Flow Diverter