Experimental Pathological Study on the Postoperative Suture Granuloma in Rats

After a skin incision, spay and castration for rats, histopathological changes were compared against six different sutures widely used in the clinic. Spayed and castrated rats wereeuthanized at 30 days and 60 days after surgery, respectively. At necropsy, cutaneous fibrosis and yellowish masses of various sizes were observed in the spayed and castrated parts. Histopathologically, the lesions were characterized by various stages of foreign granuloma containing the suture materials. The inflammatory reaction wa more significant in spayed and castrated sites than in the sites of skin incision. Silk and absorbabl multifilamentsutures have produced the strongest tissue reaction among the tested suture materials. Theresults of the present study suggest that foreign granulomas occur with any suture, that tissue reactions continue as long as suture materials exist, and that the inflammatory response differs by suture materials and surgical site.