In this study, our results showed that absorbable suture creates a safe adhesion score between the mesentery which is not inferior to non-absorbable sutures.
In our experiment, we found that the mesenteric defects were completely closed in the absorbable and non-absorbable (Group D non-absorbable polyester suture) sutures groups. In the absorbable suture group, a complete absorption of the suture which leaves a smooth plane along the suture may be added advantage. Therefore, we believed that absorbable sutures are safe and not inferior to non-absorbable suture to close mesenteric defect
Many materials are currently being used by surgeons to close the mesenteric defects. These include various non-absorbable sutures, stapler, biological glue, hernia mesh, hernia clips and so on[4, 9, 11, 18-20]. Some surgeons are accustomed to closing the mesenteric defects using prolene sutures because of its non-absorbability and smoothness. Remarkably, our experiment results indicated that adhesion in prolene group was minimum. Importantly, we found gaps formed between the suture and mesentery along the suture line likely indicating that using prolene sutures may not be safe to close the mesenteric defect probably because of the light tissue response and little adhesion. Moreover, after bariatric surgery this situation is likely exacerbated by the weight loss and the decrease in mesentery fat that occurs.
This phenomenon with Prolene sutures may therefore increase the risk for postoperative internal hernia formation particularly in obesity surgery following the decrease of mesenteric fat as a result of weight loss after gastric bypass. Using another non-absorbable suture (4-0 Polyester suture) we found a complete closure and adhesion of the mesenteric defect although the suture was still present. We want to emphasize that IH may still occurred after operation irrespective of the suture material due to improper suture technique.
Biological glue can also be used to close mesenteric defect based on findings in this study. However, the use of glue was associated with surrounding tissue and intestinal adhesion in the area the glue was applied. The average adhesion score in the glue group was the highest among all groups. Therefore, it is feasible to use the glue to close the mesenteric defect, but the risk of intestinal and surrounding tissue adhesion is high, likely because it is difficult to control the amount of glue during application. But, in the study by Mark Magdy et al,  they closed the Petersen’s space mesentery defect using bioabsorbable mesh with fibrin glue fixation with a good result.
It is currently unknown whether closing the mesenteric defect with absorbable sutures creates a safe adhesion compared to non-absorbable suture. The purpose of this study was to try to explore this question. The results of our study showed that Absorbable sutures creates a safe adhesion score between the mesentery which is not inferior to non-absorbable sutures. Additionally, the use of absorbable suture showed a complete closure of the mesentery defect with the sutures completely absorbed leaving a smooth plane along the sutured line. There were no visible bowel adhesions or internal herniation. This indicates that absorbable sutures are safe in closing mesenteric defects.
Gumbs et al  analyzed 152 patients in whom laparoscopic Roux-en-y gastric bypass (LRYGB) was performed. They recorded that jejunojejunal anastomotic obstruction occurred in 7 patients due to small intestine adhesion, which was attributed to the Dacron suture. Their study therefore indicated that non absorbable suture is not a good selection to close the jejunojejunal mesenteric leaves defect.
No matter what suture is used, the closure of the mesenteric defect ultimately depends on the adhesion between mesentery. Comparing all methods used in our experiment, applying absorbable suture and non-absorbable suture (polyester suture) to close the mesenteric defect were equally safe. However, the absorbable suture may be superior to the non-absorbable suture and glue to close the mesenteric defect, because it did not cause extra adhesions perhaps due to the complete absorption.
Here, we need to emphasize that different absorbable sutures require different time for absorption. The time require for absorption of the absorbable suture used in our experiment is about 2 months. So it is unknown if other absorbable sutures (shorter or longer absorbable time) could create safe adhesion in the mesenteric defect. We think a suture with too short absorbable time (one or two weeks) may not be suitable for closing the mesenteric defects, because adhesions between mesentery may not have formed or not be firm enough after such a short period of time.
The obvious shortcoming of this study is the use of animal model to perform the experiment which cannot completely represent humans, and absence of internal hernia in any group may be due to the small number of rats. Therefore much larger studies are need.
Although we have used absorbable sutures to close the mesenteric defect in dozens of patients with radical gastrectomy and no IH was found after more than one year of follow-up, larger clinical trial or multi-center studies are needed to clarify the safety of absorbable sutures in closing the mesenteric defects.