Porous alloplastic material encasement of gold weights for the treatment of paralytic lagophthalmos.

Abstract

To determine if encasing gold weights in a porous alloplastic material would improve their longevity in situ. Gold weights used for passive eyelid reanimation in patients with paralytic lagophthalmos were wrapped in either expanded polytetrafluoroethylene (E-PTFE) or porous polyurethane (PPU) to allow cellular infiltration and ingrowth and increase the blood supply to the site of the implant. A total of 14 implants, six encased in E-PTFE, six encased in PPU, and two with no casings (controls), were tested for biocompatibility and stability in rabbit eyelids for 10 months. Two of the PPU-encased gold weights showed some anterior extrusion, one at 3 months and one at 5 months after implantation. All of the E-PTFE-encased gold weights and both control weights were well tolerated for the entire study period. Histology of the alloplastic casings and surrounding tissues showed good tissue compatibility and cellular ingrowth for both alloplastic materials. Encasing the weights in a biocompatible alloplastic material, such as E-PTFE, may decrease micromovement and improve attachment to the eyelid tissue, as well as increase blood supply to the area, thereby reducing the rates of the major complications--infection and extrusion--associated with these implants.