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This study was designed to test the effect of recombinant tissue-type plasminogen activator (rt-PA) in reducing adhesion formation and to observe its influence on peritoneal neoangiogenesis. In 20 Wistar rats, a 4-cm midline incision was made, and a square piece of Silastic, 0.5×0.5 cm and 0.2 mm thick, was fixed on the right side of the peritoneum with two separate angular stitches of nylon 9/O. The rats were randomized into two groups of 10 animals each. In the first group we injected 0.2 mg of rt-PA intraperitoneally three times a day. The second group of 10 rats was used as a control group. Each rat was reoperated on day 12. Intraperitoneal injection of rt-PA seemed not to affect adhesion formation, as a 100% adhesion rate was reported in the treated group compared with 90% of the control group. The results showed that rt-PA acts on the neoangiogenesis involved in postsurgical adhesion formation by reducing the size and length of the vessels. This action seems to slow down peritoneal healing with a negative effect on postsurgical adhesion prevention.

This study presents an animal model for the observation of adhesion formation, from a vascular viewpoint. In 60 Wistar rats, a 4 cm midline incision was made and a 0.5 cm square piece of silastic 0.2 mm thick was fixed on the right side of the peritoneum with two separate angular stitches of nylon 9/0. The rats were randomized in six groups of 10 animals and were operated on again on days 2, 4, 6, 8, 10 and 12 respectively. Biopsies for scanning electron microscopy were obtained by resecting a 2 x 2 cm square of parietal peritoneum around and covering the silastic patch. Foreign body reaction induced by the silastic patch and ischaemia caused by stitching are the stimuli for adhesion formation. The results showed a gradual progression in the type and tenacity of adhesion formation. The maximal degree of peritoneal reactive angiogenesis was noted between days 8 and 12, together with a decrease and a redistribution in the extent of adhesions. In the early stages, vascularization is part of the organization of adhesions while their extent is limited. Two parallel mechanisms take part in trauma healing: while omento-parietal adhesions are vascularized, new peritoneal tissue with its vascular network develops and covers the silastic surface and the traumatized area. This theory is supported by the presence of fibroblasts differentiating into mesothelial cells on day 8. Theoretically, a valid treatment in preventing adhesion formation should increase the peritoneal neoangiogenesis and the repair of peritoneal lesions, but at the same time prevent the vascularization of adhesions. The present model offers the possibility of testing the effect of any treatment or device for preventing post-operative adhesions in a relatively short time.

The reproductive prognosis of 115 women desiring pregnancy who underwent surgery for ectopic pregnancy between 1985 and 1990 at the Clinica Luigi Mangiagalli, was analysed after a median follow-up period of 26 months (range 2-83). Probability of reproductive events was assessed by a product-limit model. Women who underwent surgery for ectopic pregnancy had a 54% probability of becoming pregnant (cumulative pregnancy rate, CPR), and a 36% probability of giving birth to a child (cumulative livebirth rate, CLB) during the 3 years after surgery. These percentages dropped with history of previous ectopic pregnancy (respectively 33%, P = 0.07, and 7%, P or = 35 years and CPR = 37% and CLB = 20% in women with adhesions in the contralateral tube), but these findings were not statistically significant. No association emerged between fertility and parity or type of surgery. The recurrence rate of ectopic pregnancy was 20%. No significant association emerged between recurrence of ectopic pregnancy and age, history of previous pregnancy, history of previous ectopic pregnancy, non-intact contra-lateral tube and salpingotomy.

Summary. The restoration of normal tubo-ovarian function was investigated in a training programme using oviduct anastomosis in the rabbit as an experimental model. Ovulation rate, pregnancy rate, nidation index, implantation failure index and degree of adhesions were used as parameters. More than 100 anastomoses had to be performed to reach a perfect degree of atraumatic, function-restoring surgery. It is concluded that the most difficult aspect in female infertility surgery is not the use of the operating microscope but the experience in applying the principles of atraumatic surgery.