Stress urinary incontinence (SUI) is defined as the involuntary urine leakage with increased intra-abdominal pressure. The conventional management of SUI depends on the implantation of polypropylene midurethral slings (MUS), which are effective but may be associated with significant tissue ingrowth, making removal difficult and increasing morbidity in revision cases. We hypothesize that a novel expanded polytetrafluoroethylene (ePTFE) MUS is able to demonstrate favorable biocompatibility, minimal tissue adhesions, and improved ease of explantation compared to conventional materials. The aim of this study was to evaluate tissue response, positional stability, and removability of this novel sling in a clinically relevant porcine model.

This original prospective preclinical study evaluated six female Yucatan mini pigs (30–50 kg) implanted with a purpose-designed ePTFE MUS (RebedaTek, LLC) with pore size less than 1 µm. The sling incorporates fluorinated ethylene propylene (FEP) pledgets at each end to facilitate anchoring to the obturator membrane.
Each animal underwent transvaginal placement of the MUS through a small vaginal incision. The sling was positioned at the mid-urethra and secured bilaterally using the FEP pledgets. Excess sling length was intentionally rolled into the periurethral space to simulate clinical placement. After a 12-week implantation period, the slings were explanted, and removal time was recorded. Tissue samples from the periurethral region and anchor sites were collected for histological evaluation. Comparable tissue specimens were also obtained from a single control animal.
Primary endpoints included feasibility and reproducibility of implantation, evidence of migration, ease of removal measured by explantation time and biocompatibility assessed as evidence of inflammation and fibrosis.  Procedural and postoperative complications were also documented.

All animals remained clinically well throughout the 12-week study period with no procedure-related adverse events and no evidence of sling migration. Explantation was rapid and consistent, with a mean removal time of 12.4 ± 2.84 seconds. Gross examination demonstrated minimal tissue adhesion to the sling material.
Histological analysis showed no significant inflammatory response and only mild fibrosis at both periurethral and obturator anchoring sites. MUS extrusion into the vagina was observed in three animals at the time of explantation; this was attributed to excess sling length rather than material characteristics. Importantly, there were no signs of infection or inflammation associated with these extrusion sites.

The ePTFE MUS demonstrated no tissue ingrowth and a low inflammatory profile, which likely contributed to the rapid and uncomplicated explantation observed. The absence of infection and limited fibrosis suggest favorable biocompatibility. Observed extrusion events appear to be related to implantation technique, specifically excess sling length, rather than intrinsic material properties.

This novel ePTFE midurethral sling shows promising performance in a porcine model, with excellent biocompatibility and ease of removal. These characteristics may address key limitations of existing polypropylene slings. Our findings should prompt further evaluation of efficacy and safety in clinical trials.