Case 1: One Stent in Curved Aneurysm Geometry. A rough approximation of a patient's aneurysm geometry was taken into account. The aneurysm is shown in . Numerical simulations were obtained for a single sheet of Wallstent placed in the aneurysm. The stent position obtained by using numerical simulation is shown in (for the purpose of clarity, the aneurysm sac is not shown). should be compared to : both the numerical simulation and the patient's actual angiogram show that at the systolic peak the stent expands inside the aneurysm's sac. This shows that indeed a single sheet of Wallstent endoprosthesis is much more elastic (compliant) than is the wall of the native aorta. The drastic change in the diameter of the inserted stent causes the length of the stent to decrease (), thereby exerting high stresses near the anchoring sites. This numerical experiment, together with the patient's angiogram () and our previous measurements of the elastic properties of the Wallstent, indicate that optimal stent design for endoluminal treatment of AAA needs to include stiffer structure in the central section. Multiple sheets of Wallstent, placed in the center of the prosthesis, should improve endovascular stenting of AAA. This is discussed in Case 3.
We performed a numerical study of the dynamic response of the Wallstent endoprosthesis to the pulsatile forces exerted by blood flow. Numerical simulations used the data from the in vivo measurements of vascular wall properties that corresponded to the aneurysmal aorta, from the flow rate at the proximal end of the abdominal aorta, and from the in vitro measurements of the mechanical properties of the Wallstent. We show here, in a series of images, the response of several configurations of stents at the systolic peak. At this point, we are not interested in precise, patient-specific study of prosthesis performance. Rather, we want to identify the general properties of prostheses that can be improved for better performance.
71-218: Boston Scientific WallStent RP Iliac SE 8mm x 38mm, 75cm
The response of the metallic Wallstent endoprosthesis with respect to static pressure load was measured experimentally and modeled using the slender rod theory. The following are our findings.
Wallstent endoprosthesis mri safety | scholarly search
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Abstract The Wallstentendoprosthesis was placed in 12 renal ..
We performed this study in order to analyze the mechanical properties of bare-metal Wallstent® endoprostheses and of AneuRx® stent-grafts and to compare their responses to hemodynamic forces. Mathematical modeling, numerical simulations, and experimental measurements were used to study the 2 structurally different types of endoprostheses.
WALLSTENT® (Tips, Iliac, ..
Murphy TP, Ariaratnam NS, Carney WI, Marcaccio EJ, Slaiby JM, Soares GM. Long-term experience with stent treatment of aortoiliac insufficiency. Radiology 2004; 231(1): 243-249.
the Wallstent in the iliac and femoral arteries.19 ..
Murphy TP. Comparing the SMART stent with the Wallstent iliac endoprosthesis: reading between the lines. J Vasc Interv Radiol. 2004;15(9):907-9.
BostonScientific Carotid Wallstent Mono- rail Endoprosthesis ..
Murphy TP, Soares GM, Kim HM, Ahn SH, Raas RA. Quality-of-Life and Exercise Performance After Aortoiliac Stent Placement for Claudication. J Vasc Interv Radiol. 2005 Jul;16(7):947-53.