Retromuskul?re Netzplastik in Deutschland

Ausgehend von den entt?uschenden Ergebnissen der prim?ren Nahtreparation von Narbenhernien und neueren Forschungsergebnissen, die eine gest?rte Narbenbildung als wesentliche Ursache nahe legen, ist die Netzplastik heute als Methode der Wahl zur Reparation von Narbenhernien anzusehen. Eine konsequente Weiterentwicklung der seit über 40 Jahren eingesetzten Polypropylennetze führte zu den von uns favorisierten gro?porigen, materialreduzierten Prothesen, die den physiologischen Bedürfnissen der Bauchwand angepasst sind und eine optimale Gewebsintegration sicherstellen. Dabei lie?en sich mit der retromuskul?ren “Sublay-Position” die auch reproduzierbar besten Ergebnisse erzielen. Als wesentlicher Vorteil ist hierbei die Fixierung der Prothese durch den intraabdominellen Druck anzusehen. Im Langzeitverlauf lassen sich hiermit Rezidivraten von unter 10% realisieren. Analysiert man die nach vermeintlich korrekt durchgeführter “Sublay-Reparation” m?glichen Rezidivhernien, so ist im Wesentlichen eine inad?quate überlappung der Prothese meist am kranialen oder kaudalen Ende der Inzision für das Versagen der Operation verantwortlich zu machen. Aus unserer Sicht stellt daher eine überlappung von mindestens 5–6 cm in allen Richtungen eine zwingend einzuhaltende Voraussetzung für eine erfolgreiche Operation dar. Insbesondere mit den modernen leichtgewichtigen Netzen lassen sich mit der retromuskul?ren “Sublay-Netzplastik” exzellente Ergebnisse bezüglich Rezidivraten, Komplikationen und Patientenkomfort erzielen.     

Titanium coating of a polypropylene mesh for hernia repair: Effect on biocompatibilty

Titanium and its alloys are used worldwide in surgery. The favorable characteristics that make this material desirable for implantation are corrosion resistance and biocompatibility. Concerning hernia repair, a mesh modification has been developed using titanium layering of a polypropylene mesh implant, which is said to lead to an improved biocompatibility compared to commercially available mesh materials. To analyze the pure effect of titanium coating, two different mesh structures were studied using a standardized animal model. The titanium-coated monofilamentous, large porous, and lightweight mesh made of polypropylene and coated with titanium (PP+T) was compared to a pure polypropylene mesh manufactured with a similar structure and amount of material serving as a control (PP). In Sprague-Dawley rats, mesh samples were placed in a subcutaneuous position. Then 56, 84, and 182 days after mesh implantation, three animals from each group were sacrificed for morphological observations (amount of inflammatory and connective tissue formation, percentages of proliferating and apoptotic cells, percentage of macrophages). Both mesh modifications investigated showed an overall good biocompatibility. Macroscopic clinical observation after implantation of up to 182 days was uneventful. The tissue response to the PP as well as to the PP+T mesh was characterized by a moderate inflammatory tissue reaction limited to the perifilamentary region as is known for low weight, large porous, and monofilamentous mesh structures. No significant improvement of biocompatibility was found when analyzing the effect of titanium coating compared to the pure polypropylene mesh structure.     

Hepatobili?re Anastomosentechniken

The success of hepatobiliary anastomoses is influenced by the diameter of the bile duct, the location within the biliary tract, the situation of primary or revision surgery and accompanying infections. The exact preoperative diagnostics of the anatomy of the biliary tract are indispensable for low complication rates. Within reconstructive surgery, hepaticojejunostomy has been established as the standard technique and a biliodigestive anastomosis is performed proximal to the cystic duct and 2?C3?cm below the fork in the hepatic duct. In general, end-to-end anastomoses of the common bile duct are not recommended due to the high risk for stenosis. Within the liver hilus an exact preparation of all tubular structures is mandatory. With regard to possible perioperative complications operations on the hepatic duct or segmental bile ducts should be performed in specialized centers. Methods of drainage in hepatobiliary surgery are percutaneous transhepatic cholangiodrainage (PTCD), internal-external drainage, internal drainage with endoscopic or surgically placed stents, external-internal-external drainage and the T-drain.     

Mesh implants in hernia repair. Inflammatory cell response in a rat model

BACKGROUND: In the reinforcement of the abdominal wall with mesh implants, various complications including hernia recurrence, abdominal pain, seroma formation and infection are discussed to depend on the biocompatibility of the alloplastic prosthesis. Particularly macrophages, T-cells and mast cells have been shown to play a major role in the inflammatory response to biomaterials. To approach biocompatibility of surgical meshes we therefore examined the infiltrate of these cells as well as the proliferation rate in response to different clinically applied materials. MATERIALS AND METHODS: Three mesh materials (polypropylene: PP, Prolene; polyethylene terephthalate: PET, Mersilene, and polypropylene/polyglactin: PP + PG, Vypro) were compared after inlay implantation in a standardized rodent animal model. A suture-closed laparotomy served as control. After 7 and 90 days of implantation, histochemical analysis of the inflammatory response to all biomaterials was performed: macrophages (ED3), T-cells (CD3), proliferating cells (PCNA) and mast cells (Giemsa) were investigated. RESULTS: In all groups a persisting T-cell response was observed. Colonization of the interface with macrophages showed a pronounced reduction in the PP + PG-mesh group. Infiltration of mast cells at the tissue graft interface showed a time-dependent decrease in the PET- and PP + PG-mesh groups, whereas in contrast, index of mast cells increased in the PP-mesh group. At both time points, indices of proliferation were highest in the PP-mesh group. CONCLUSION: The present data confirm the development of a biomaterial-dependent chronic inflammatory response to surgical meshes with macrophages as the predominant cell type. Further research on the recruitment of inflammatory cells and in particular on the role of mast cells and their granular products should be encouraged.     

Adhesion formation of a polyvinylidenfluoride/polypropylene mesh for intra-abdominal placement in a rodent animal model

Background  Effective laparoscopic ventral herniorrhaphy mandates the use of an intraperitoneal mesh. Visceral adhesions and shrinkage of prosthetics may complicate repairs. The aim of this study was to compare adhesion formation, mesh shrinkage and tissue ingrowth after intra-abdominal placement of a novel two-component monofilament mesh structure made of polypropylene (PP) and polyvinylidenfluoride (PVDF) with current alternatives. Materials and methods  Forty Sprague-Dawley rats were used in this study. Mesh samples were fixed as intra-abdominal only mesh at the right lateral abdominal wall. The study groups were: PVDF+PP (polypropylene parietally and polyvinylidenfluoride viscerally), PP+Col (polypropylene with a collagenoxidized film), ePTFE (smooth surface viscerally and a textured surface parietally), and PP (a pure polypropylene mesh serving as control). The meshes were explanted after 30 days. Adhesions were scored as a percentage of explanted biomaterials’ affected surface area; prosthetic shrinkage was calculated. Foreign-body reaction to mesh materials was measured by investigating the amount of inflammatory infiltrate and fibrotic tissue formation. Results  In terms of adhesion score, the pure PP mesh showed the highest values followed by the ePTFE, PVDF+PP, and PP+Col meshes. Quantitative assessment of adhesion area revealed a significantly higher value of the pure PP mesh sample (62.0 ± 22.1%) compared with the PP+Col (26.8 ± 12.1%) and the PVDF+PP mesh (34.6 ± 8.2%). Percentage of shrinkage showed a significantly higher value of the ePTFE mesh (52.4 ± 13.9%) compared with all other mesh modifications (PP+Col 19.8 ± 13.9%, PVDF+PP 19.9 ± 7.0%, and PP 26.8 ± 9.5%). Inflammatory infiltrate was significantly reduced in the PVDF+PP mesh group compared with all other mesh samples. Conclusion  The use of the novel two-component monofilament mesh structure made of polypropylene and polyvinylidenfluoride was found to be favorable regarding adhesion formation and mesh shrinkage compared to conventional mesh materials used for intra-abdominal placement.     

Angiography in the diagnosis and therapy of frostbite.

Five patients with frostbite injury were studied by selective angiography and treated by selective intra-arterial application of reserpine with follow-up angiography two days later. Control angiograms showed various degrees of vascular spasm as well as organic stenosis and occlusion. Intra-arterial reserpine produced dramatic subsiding of vasospasm, as evidenced by angiography and relief of clinical symptoms. Complete healing without tissue loss occurred in 4 patients. Amputation was necessary in one case, due at least in part to pre-existing peripheral atherosclerotic disease. Selective angiography was found to contribute significantly to both the diagnosis and therapy of frostbite injury.