[Anatomo-pathological evolution of single-layer end-to-end digestive anastomoses. A study of 210 colonic anastomoses in rats from the 2d to the 180th day].

Two hundred and ten left colonic single-layer end-to-end anastomoses (105 by extramucosal continuous suture, 53 by extramucosal interrupted sutures, 52 by total continuous suture) performed on 105 rats with microsurgical techniques using a slowly resorbed suturing material were examined histologically at nine different times between the 2nd and the 180th days. The histopathological evolution of the inflammatory granuloma, the granulation tissue, the reepithelialization process and the restoration of the smooth muscle layers are described. The rate and the amount of inflammation were found to differ between animals and three different types of evolution could be schematized. The differences could not be due to the suturing techniques since continuous and interrupted sutures gave the same results, but rather to the manner of treating the intestinal cut edges before and during suturing. The amount of inflammation was found to decrease with the operator's training.