Supplementary Fig.ure1.Technique used for aneurysm creation. (A) After exposure of the right external jugular vein, a 1-cm long venous pouch without branches, with one end ligated and the other open, was excised. (B) After blunt dissection of the right CCA, 1 cm of the right CCA was isolated and temporarily clipped proximally and distally with two atraumatic hemostatic clamps. An incision was made between the two clamps. (C) An end-to-side anastomosis was created between the free end of the venous pouch and the CCA wall by discontinuous extroversion sutures with 6-0 stitches. (D) Lateral aneurysm model established in the right CCA.

Supplementary Fig.ure2.IVUSimage of group A at 12 months follow-up. (A)IVUS image. (B)The methods for analysis of lumen stenosis on IVUS. Intrascaffold area (the areas within the yellow line), neointimal area(the areas between the yellow and red line), and lumen area (the areas within the red line).Percent of lumen stenosis was calculated asthe mean lumen intrascaffold area −thelumen area) ÷ mean lumen intrascaffoldarea× 100.

SupplementaryFig.ure3.SEM images of luminal side of stented arteriesin group B with micrographs at higher magnification on the top panels. (A) The full view SEM 1 month after Willis covered stent placement showed that the stent struts could be clear seenon luminal surface of stented arteries (Scale bar = 1.0 mm). The micrographic SEM showed that the luminal surface was covered with round/oval endothelial cells (Top panels, scale bar = 100μm). (B) The full view SEM3months after Willis covered stent placement showed that the stent struts of Willis covered stent were also recognized (Scale bar = 1.0 mm). The micrographic SEM showed the stripped endothelial cells were observed in full luminal side of the Willis covered stent (Top panels, scale bar = 200 μm). (C) The full view SEM6months after Willis covered stent placement showed thatthe stent struts of Willis covered stent could also be blurred recognized (Scale bar = 1.0 mm), and the micrographic SEM exhibited the stripped endothelial cells were could also be seen in the stent struts of the Willis covered stent. (Top panels, scale bar = 100 μm).

SupplementaryFig.ure4.VVG staining, HE staining (Low magnification) and HE staining (High magnification) images of stented arteries in group B after 90 days, 180 days and 360 days of stent implantation. Scale bar in VVG and HE(L) = 1 mm; scale bar in HE(H) = 200 μm.

The histomorphometry and histopathologicalimages show that thestent strut (arrow) of Willis covered stentwas not degradedand the neointimal area (arrowhead) was increased with extension of the follow-up time.

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Eur Radiol (2016) Cui HK, Li FB, Zhang MQ et al.