TY  - JOUR
A1  - Horbach, Andreas
A1  - Staat, Manfred
T1  - Optical strain measurement for the modeling of surgical meshes and their porosity
JF  - Current Directions in Biomedical Engineering
N2  - The porosity of surgical meshes makes them flexible for large elastic deformation and establishes the healing conditions of good tissue in growth. The biomechanic modeling of orthotropic and compressible materials requires new materials models and simulstaneoaus fit of deformation in the load direction as well as trannsversely to to load. This nonlinear modeling can be achieved by an optical deformation measurement. At the same time the full field deformation measurement allows the dermination of the change of porosity with deformation. Also the socalled effective porosity, which has been defined to asses the tisssue interatcion with the mesh implants, can be determined from the global deformation of the surgical meshes.
Y1  - 2018
U6  - http://dx.doi.org/10.1515/cdbme-2018-0045
SN  - 2364-5504
VL  - Band 4
IS  - 1
SP  - 181
EP  - 184
PB  - De Gruyter
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Ciritsis, Alexander
A1  - Horbach, Andreas
A1  - Staat, Manfred
A1  - Kuhl, Christiane K.
A1  - Kraemer, Nils Andreas
T1  - Porosity and tissue integration of elastic mesh implants evaluated in vitro and in vivo
JF  - Journal of Biomedical Materials Research: Part B:  Applied Biomaterials
N2  - Purpose
In vivo, a loss of mesh porosity triggers scar tissue formation and restricts functionality. The purpose of this study was to evaluate the properties and configuration changes as mesh deformation and mesh shrinkage of a soft mesh implant compared with a conventional stiff mesh implant in vitro and in a porcine model.

Material and Methods
Tensile tests and digital image correlation were used to determine the textile porosity for both mesh types in vitro. A group of three pigs each were treated with magnetic resonance imaging (MRI) visible conventional stiff polyvinylidene fluoride meshes (PVDF) or with soft thermoplastic polyurethane meshes (TPU) (FEG Textiltechnik mbH, Aachen, Germany), respectively. MRI was performed with a pneumoperitoneum at a pressure of 0 and 15 mmHg, which resulted in bulging of the abdomen. The mesh-induced signal voids were semiautomatically segmented and the mesh areas were determined. With the deformations assessed in both mesh types at both pressure conditions, the porosity change of the meshes after 8 weeks of ingrowth was calculated as an indicator of preserved elastic properties. The explanted specimens were examined histologically for the maturity of the scar (collagen I/III ratio).

Results
In TPU, the in vitro porosity increased constantly, in PVDF, a loss of porosity was observed under mild stresses. In vivo, the mean mesh areas of TPU were 206.8 cm2 (± 5.7 cm2) at 0 mmHg pneumoperitoneum and 274.6 cm2 (± 5.2 cm2) at 15 mmHg; for PVDF the mean areas were 205.5 cm2 (± 8.8 cm2) and 221.5 cm2 (± 11.8 cm2), respectively. The pneumoperitoneum-induced pressure increase resulted in a calculated porosity increase of 8.4% for TPU and of 1.2% for PVDF. The mean collagen I/III ratio was 8.7 (± 0.5) for TPU and 4.7 (± 0.7) for PVDF.

Conclusion
The elastic properties of TPU mesh implants result in improved tissue integration compared to conventional PVDF meshes, and they adapt more efficiently to the abdominal wall. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 827–833, 2018.
Y1  - 2018
U6  - http://dx.doi.org/10.1002/jbm.b.33877
SN  - 1552-4981
VL  - 106
IS  - 2
SP  - 827
EP  - 833
PB  - Wiley
CY  - New York, NY
ER  -