RESUMO
Objective To investigate the effect of external beam irradiation re-stenosis in form of neointimal hyperplasia following carotid endarterectomy in rabbits. Methods 144 Japanese white rabbits were divided into 24 groups, with 6 rabbits in each. All animals underwent carotid endarterectomy and were fed on hypercholesterol diet. The vessels which underwent surgery were irradiated with 6 MV photon, to a dose of 0, 6, 12, 18, 24 and 30 Gy. The animals were sacrificed on D15, 30, 60 and 90 after irradiation. The irradiated vessels were examined with histopathology and immunohistochemical methods. Results The differences in the values of neointimal area/media area, proliferating cell nuclear antigen (PCNA) stain, a-Acn'n stain and platelet-derived growth factor (PDGF) stain were all significant (P
