Full thickness abdominal wall defect in growing rats as a model for congenital diaphragmatic hernia prosthetic repair.

[congenital diaphragmatic hernia]

Large congenital diaphragmatic hernia may require prosthetic correction . Acellular collagen matrices were introduced to avoid complications owing to the use of synthetic patches . We tested 3 different ACM for reconstruction of an abdominal wall defect in an animal model that mimics the fast growth during infancy .Pelvisoft ® (CR Bard , Covington , GA ) and 2 investigational ACM were used for primary reconstruction of a full thickness abdominal wall defect . 3 months -old rats (n =26 ) were allowed to survive for 90 days after implantation . Anatomical , tensiometric and histological analyses were performed . Based on good outcomes , we did the same with 1 month -old rats (n =54 ). Unoperated rats were used for obtaining reference tensiometric values of selected native tissues .Major wound complications were exclusively observed in 1 month -old rats . All explants in both groups thinned significantly (p <0 .03 ) and had an elastic modulus increasing over time , far above that from native tissues at 90 days of life . Both investigational ACM induced a more vigorous foreign body reaction than Pelvisoft (®).The shift from 3 to 1 month -old rats was associated with wound complications . Pelvisoft ® showed a better biocompatibility than the 2 investigational ACM . Passive biomechanical properties of all explants were still not comparable to that of native tissues .