Effects of preoperative irradiation using fractioned electron beam on the healing process of colocolonic anastomosis in rats undergoing early and late surgical intervention

ABSTRACT

PURPOSE: To investigate the effects of preoperative fractioned irradiation using an electron beam on the healing process of colocolonic anastomoses in rats that underwent early and late surgical intervention. METHODS: Thirty Wistar rats, distributed as follows group A (surgery only), group B (fractionated irradiation for 30 days (if), surgery seven days after the end of it), group C (if for 30 days, and surgery after 30 days of termination). On the seventh postoperative day the anastomotic segment analysis was taken, using tension tests, histology and collagen deposition evaluation by computerized analysis. RESULTS: Regarding the tension resistance of the anastomosis, there were no statistical differences (p=0.42). However, a significant increase in cells number in the inflammatory infiltrate in the group with a longer interval between surgery and pre op radiation (p<0.05). The collagen concentration had no significant variance. CONCLUSION: The irradiation in divided doses increased local inflammatory cellularity when the surgery was performed later. This result did not affect the increase of complications, nor on the local concentration of collagen, achieving similar clinical outcomes.