PHYSICAL CHARACTERIZATION OF SURGICAL MESH AFTER FUNCTION IN HERNIA REPAIR

Abdominal hernia repair is the most commonly performed general surgery procedure in the world. Surgical hernia repair involves the implantation of a prosthetic surgical mesh, which are commonly made from polypropylene. While hernia repair with mesh is highly successful, especially using a laparoscopic technique, patients still experience complications, such as chronic pain. These complications and their relationship to mesh materials and structure warrant further investigation into the impact that mesh design factors have on in vivo performance. The broad objective of this thesis is to characterize the impact of the physiological environment on surgical mesh used for hernia repair and the related host response. This objective will be accomplished through three specific aims. The purpose of Aim 1 is to establish a registry of explanted surgical mesh and to develop appropriate handling protocols. The purpose of Aim 2 is to characterize physical and structural properties of explanted mesh through completion of mechanical testing and pore size measurements. The purpose of Aim 3 is to characterize the host response to surgical mesh through completion of histological evaluation. Through collaboration with a regional medical center, a surgical mesh registry was established that contained 102 explanted mesh. Six types of commercially available polypropylene mesh from the registry were selected to undergo mechanical testing and pore size measurements. In general, the results of mechanical testing showed losses in stiffness in explanted mesh when compared to pristine samples of the same type. Additionally, explanted mesh showed reductions in pore size when compared to pristine mesh samples. Histological evaluation of twelve mesh revealed differences in the foreign body response to mesh of different materials and weights. The results from this thesis provide clinically relevant data for understanding the performance of surgical mesh under physiological conditions