Biocompatibility of modified ePTFE for an artificial dura mater

Abstract

Expanded polytetrafluoroethylene (ePTFE) is one of the biomedical materials and is most extensively used in surgical repair in various anatomical sites. However, ePTFE as an artificial dura mater is often associated with postoperative leakage of the cerebrospinal fluid (CSF) because of its very low adhesiveness to fibrin glue and surrounding tissue. To overcome CSF leakage the effects of ion-beam irradiation to ePTFE surface were examined. The surfaces of ePTFE were irradiated with 50 or 150keV Ar+-beam with fluences of 1×1014, 5×1014 and 1×1015ions/cm2. L929 fibroblasts were cultured for 24h on the ePTFE that included the irradiated domains and non-irradiated area. It was confirmed that fibroblasts adhered better to the irradiated domains compared with non-irradiated domain, however the difference was not noted among the individual irradiation conditions.A dural defect surgically created in a rabbit skull was patched with ion-beam irradiated ePTFE. CSF leakage was observed in the case with non-irradiated ePTFE and 50keV with 1×1014 and 5×1014ions/cm2 irradiated ePTFE, but CSF leakage did not occur in cases with other ion-beam irradiated ePTFE. A histological study indicated that fibroblast-like cells invaded and anchored into the gaps of the ePTFE surface created by ion-beam irradiation.