Repair of the tarsoligamentous sling in New Zealand white rabbits using polytetrafluoroethylene graft material.

Repair of large full-thickness lower lid defects requires reconstruction of the tarsoligamentous sling. This may necessitate either a tarsus sharing technique or a skin flap with a free cartilage graft. Obtaining tarsus or cartilage in these procedures has the disadvantage of requiring a second surgical site, which may cause further scarring and deformity. Polytetrafluoroethylene (PTFE) is a nonantigenic, inert, highly biocompatible, mechanically strong synthetic material that has been successfully utilized as a vascular and soft tissue patch since the 1970's. PTFE has been used in ophthalmic surgery to wrap orbital implants and as an interpositional graft for the correction of lower lid retraction. We evaluated the usefulness of PTFE in the reconstruction of the tarsoligamentous sling in 24 lids of 12 New Zealand white rabbits. PTFE with internodal spacings of 10 and 30 microns were used initially. Despite a lack of tissue inflammation, the PTFE grafts were uniformly extruded by 2 weeks postoperatively. Four additional lids were reconstructed using PTFE (30 and 60 microns) coated with a biological substrate. This graft material was also extruded. These results suggest that PTFE material may not be satisfactory for reconstruction of the tarsoligamentous sling.