Medpor lower eyelid spacer: does it biointegrate?

Purpose: To report the histopathologic findings of explanted Medpor® lower eyelid spacers (LES) in complicated cases. Materials and Methods: Four cases of lower eyelid retraction due to thyroid orbitopathy (n = 2), facial nerve palsy (n = 1), and post-enucleation socket syndrome (n = 1) were treated with Medpor® LES. Results: All implants were removed between 6 months to 2 years following their original insertion due to exposure, poor stability, or contour. Histopathology of the implants showed fibrosis and vascularization although clinically, at the time of removal, did not appear vascularized. In addition, immunohistochemistry was positive for Factor VIII related antigen and CD34, thus highlighting the presence of vessels in the pores and around the implant. Conclusion: To our knowledge, we are the first to report histopathologic findings of explanted high-density porous polyethylene implants from the lower eyelid in humans. Although this study shows that Medpor® LES does biointegrate, we advocate using...