Evaluation Of Novel Absorbable Mesh In Rat Abdominal Wall Defect Repair

ObjectiveTo observe the effectiveness and biocompatibility of novel bioabsorbable mesh forrepairing abdominal wall defect in rats.MethodsFifty four Wistar rats(sex unlimited, about3months old and weighing250-300g)were randomly divided into3groups according to：chitosan groups，surgisisgroups，PPM groups. Full thickness defects of abdominal wall were created throughsurgery and repaired with the above three mesh. The adhesion of six rats of each group wasobserved via laparotomy, and the mesh with adjacent tissue was harvested for histologicalobservation on pod14,30,90.Results1. One rat of the PPM group and one rat of the CHI group were dead of infection.The abdominal wall defects of the rest of the rats could be repaired at different time aftersurgery, and the wound infection rates of three groups did not have significant differences.On the basis of the modified Katada criteria, adhesion score was significantly higher inCHI group than that in SIS group at different time points postoperatively(P<0.05).2. Histological study showed that on inflammatory cell infiltration, group CHI had ahigher score than group SIS and group PPM, acute inflammatory reaction of group CHIcan still be seen at14days, in addition, the cases that foreign body giant cells swallow thematerial of mesh appeared many times in group CHI. There were only chronicinflammatory cells in group SIS and group PPM at three time points after surgery, thescores of chronic inflammatory reaction of this two groups had no significant differences atthe first two time points, but at90days, group SIS had milder inflammatory reactionsignificantly. On fibrogenic response, group CHI and group PPM had a higher score thangroup SIS, masson trichrome stain showed plentiful collagenous fiber, neverthelessfibroblasts and myofibroblasts arranged more regularly in group SIS. Neovascularization can be seen at early phase in all groups.ConclusionThis bioabsorbable chitosan mesh could guided sufficient collagen fiber hyperplasia,and could repair the defect of abdominal wall successfully, but compared with biologicalmesh and polypropylene mesh whom were extensively applied in clinic, Thisbioabsorbable chitosan mesh had more serious inflammatory reaction, less effective inanti-adhesion, it still need further improvement to reduce the level of inflammatory reactonand to improve its biocompatibility.