The Effect Of Preoperative Irradiation On Neointima Of Arterial Graft After Abdominal Aorta And Inferior Vena Cava Replacement In Canine

Objective To observe the effect of preoperative irradiation with tumor cure dose on the neointima proliferation of arterial vascular graft, as well as covering of arterial endothelial cell to the neointima after abdominal aorta and inferior vena cava replacement.Methods 18 dogs were divided into 2 groups. Radiotherapy group was irradiated with a total dose of 28 Gy before surgery and the other not. Dogs of radiotherapy group were operated after 6 weeks of irradiation. Each dog was given subrenal abdominal aorta and inferior vena cava replacement by ePTFE prosthesis grafts. Dogs were sacrificed 4 weeks after operation. The change of autologous abdominal aorta and the neointima of artificial blood vessels was observed for histological and immunohistochemical examination.Results1,All dogs of the control group survived, and three cases of radiotherapy group died. There is a little thrombosis in 2 grafts, one in radiotherapy group, the other in control group. But no vascular cavity was obstructed completely.2,The neointima of arterial vascular graft formed completely. The arterial neointimal thickness in radiotherapy group was significantly thinner than in control group(p<0.05). The arterial intimal thickness at the middle of vascular graft was thinner than the position near the anastomosis(p<0.05). The arterial neointima near the distal anastomosis was statistically thicker than that near the proximal anastomosis (p<0.05).3,The PCNA proliferation of abdominal aorta in radiotherapy group was less than in control group(p<0.05). The PCNA proliferation at the middle of arterial vascular graft was less than the anastomosis(p<0.05), and the distal anastomosis was thicker than the proximal anastomosis (p<0.05).4,The coverage of arterial endothelial cell was incomplete in either control group or radiotherapy group.Conclusions1,No disunion, rupture was found at the anastomosis of abdominal aorta after preoperative radiotherapy at a dose of 28 Gy.2,Preoperative radiotherapy at the dose of 28 Gy can inhibit arterial neointima proliferation and the PCNA expression.3,The coverage of arterial endothelial cell was incomplete 4 weeks after artificial vascular replacement.4,The study helps judge whether a patient who have had preoprative irradiation can receive radical tumor resection accompanied with prosthetic vascular replacement of arteries.