Abstract:Objective:To observe the effect of external segmental irradiation at a total dose of 35Gy after prosthetic vessel replacement of abdominal aorta on the patency rate, the neointima proliferation and the covering of vascular endothelial cell of the vascular graft.
Methods :Prosthetic vessel replacement of abdominal aorta with ePTFE vascular graft was done in 20 mistus dogs, which were divided into control group and radiotherapy group, 10 dogs respectively. The specimen in each group were harvested at 4 weeks and 8 weeks after surgery. H-E staining, immunohistochemistry test of PCNA and CD34 were done.
Results:There was 1 case in each group with thrombosis in prosthetic vascular graft, and the patency rate was 90% in each group. Four weeks after surgery, the neointima of prosthetic vascular graft was formed completely in each group, and the intimal thickness or the PCNA expression had no statistically difference(P>0.05) between the radiotherapy and control groups, and the coverage of vascular endothelial cell was incomplete in each group; 8 weeks after surgery, the intimal thickness of radiotherapy group was statistically thinner than that of control group(P<0.05), and the intimal thickness of vascular graft in control group at the proximal, middle, and distal segment was: (72.30±9.15)μm,(40.46±7.75)μm and (98.06±6.90)μm respectively，and that in radiotherapy group was: (37.67±6.77)μm,(21.16±4.98)μm and (56.64±5.13)μm respectively. The PCNA expression was statistically less in radiotherapy group than that in control group(P<0.05). The vascular endothelial cell coverage was complete in each group.
Conclusions:The external segmental radiotherapy at a total dose of 35 Gy after prosthetic vessel replacement of abdominal aorta does not affect the patency rate of prosthetic vascular graft, and not significantily affect the vascular endothelial cell coverage, but it can inhibit the neointima proliferation and PCNA expression.