Experimental laser anastomosis of the colon

PURPOSE: Our previous experimental work showed the feasibility of colon anastomosis using laser; however, it also revealed a narrowing tendency after laser anastomosis. Long-term observation of the postoperative course of laser anastomosis was planned to assess this point. METHODS: Clinical observation and histologic examination of transverse colotomies (average, 21.2 mm) in New Zealand white rabbits (n=12) closed with a 1,064-nm neodymiumyttrium aluminum garnet (Nd:YAG) laser were carried out up to the third postoperative month, compared with closure of colotomies using a single layer of interrupted sutures of 5-0 Maxon^® (Davis & Geck, Pearl River, NY) in a control group (n=12). RESULTS: Whereas the narrowing tendency was observed up to one month after the operation in the laser group (P<0.05), it disappeared at three months following the operation without causing abnormal weight loss during the experiment. Simultaneously, there was again a marked decrease in adhesion formation following laser anastomosis (P<0.01). Collagen fibers were observed earlier in the laser group. CONCLUSIONS: An earlier commencement of collagen synthesis after laser anastomosis was proved. A narrowing tendency, which was observed from seven days to one month postoperatively, disappeared at three months after laser anastomosis without exerting any effect on growth.Supported from private sources (Colorectal Service), by the Colorectal Unit Research Fund, and by a St. Vincent's Hospital Research Grant.