An original flow diversion device for the treatment of intracranial aneurysms: evaluation in the rabbit elastase-induced model.
OBJECTIVE
The potential for successful treatment of intracranial aneurysms by flow diversion is gradually being recognized in the clinical setting; however, the devices currently available (stents) are not designed for flow diversion. We evaluate the long-term response of an appropriately designed flow diversion device in producing thrombotic occlusion of experimental aneurysms.


METHODS
Three different configurations of an original flow diversion device were implanted across thirty elastase-induced aneurysm models in rabbits. Ten animals per device configuration were followed-up for 3 weeks (n=3), 3 months (n=3), or 6 months (n=4), and tissue explanted postsacrifice was sent for histology. The temporal variation in angiographic contrast intensity within each aneurysm was fitted with a mathematical model to quantify the alteration in local hemodynamics caused by the implanted device. A predictive index, called the washout coefficient, was constructed to estimate long-term aneurysm occlusion probabilities immediately after treatment with any flow diversion device.


RESULTS
The device with a porosity of 70% and pore density of 18 pores/mm(2) performed better at occluding aneurysms than devices with 70% porosity, 12 pores/mm(2) and 65% porosity, 14 pores/mm(2). A value of the washout coefficient less than 30 predicted greater than 97% angiographic aneurysm occlusion over a period of 6 months with a sensitivity of 73% and specificity of 82%.


CONCLUSIONS
The flow diversion devices effected successful and stable aneurysm occlusion. Pore density, rather than porosity, may be the critical factor modulating efficacy of such devices.
Sadasivan
Chander
C
Department of Biomedical Engineering, University of Miami, Coral Gables, FL, USA.
Cesar
Liliana
L
Seong
Jaehoon
J
Rakian
Audrey
A
Hao
Qing
Q
Tio
Fermin O
FO
Wakhloo
Ajay K
AK
Lieber
Baruch B
BB
D000465:Algorithms; D000818:Animals; D001807:Blood Vessel Prosthesis; D002533:Cerebral Angiography; D004195:Disease Models, Animal; D042783:Endothelial Cells / Q000502:physiology; D004730:Endothelium, Vascular / Q000254:growth & development; D002532:Intracranial Aneurysm / Q000139:chemically induced* / Q000473:pathology / Q000628:therapy*; D008855:Microscopy, Electron, Scanning; D010196:Pancreatic Elastase; D016062:Porosity; D011474:Prosthesis Design; D019919:Prosthesis Implantation; D011817:Rabbits; D015607:Stents
D010196:Pancreatic Elastase