Characterisation of a human explanted polyethylene terephthalate (PET) surgical mesh following laparoscopic ventral mesh rectopexy

Polyethylene terephthalate (PET) is widely used in biomedical implants due to its mechanical strength and presumed long-term stability; however, data on its in vivo performance as a soft-tissue reinforcement mesh remain limited. To our knowledge, this study presents the first reported materials characterisation of a human-explanted PET surgical mesh following laparoscopic ventral mesh rectopexy (LVMR), providing a rare long-term dataset after 14.7 years of implantation. Low-voltage scanning electron microscopy (LV-SEM), attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR), and X-ray photoelectron spectroscopy (XPS) were used to assess structural and chemical integrity. LV-SEM demonstrated that the knitted mesh architecture was largely preserved, with fibres remaining continuous in most regions, although localised fibre discontinuities were observed at high-stress knot sites and adjacent to titanium tacks. ATR-FTIR confirmed the characteristic ester carbonyl (Cdouble bondO) and C–O–C stretching bands of PET, alongside a broad O–H absorption between 3600 and 3100 cm⁻¹, indicating surface chemical modification. XPS analysis revealed a surface layer enriched in C–O/C–OH species with a reduced ester carbonyl contribution, consistent with near-surface hydrolytic or oxidative processes. As a single-explant, case-based investigation without a pristine comparator, the findings should be interpreted as exploratory. Nonetheless, this work provides a unique reference point for the long-term in vivo behaviour of PET mesh in LVMR and highlights the need for further comparative explant studies to better understand degradation mechanisms and their clinical relevance.