title: Orbital reconstruction using porous polyethylene sheets.
abstract: BACKGROUND
  There has been growing interest in using porous alloplastic implants for reconstructive orbital surgery because of their perceived increased biocompatibility. One commercially available porous implant is high-density porous polyethylene (Medpor). It is made of pure particles of polyethylene that form interconnecting pores and have excellent handling characteristics.
  
  
  METHODS
  The authors performed 37 orbital reconstructions using 0.85-, 1.5-, or 3-mm porous polyethylene sheets to reconstruct internal orbital defects. Mean postoperative follow-up was 18.5 months. Four patients were treated for anophthalmic enophthalmos; there was one patient with spontaneous enophthalmos. In selected patients, other implants also were used, including miniplates or microplates, silastic sheets, autologous bone, or nasal septal cartilage. In patients with enophthalmos, the implants were stacked to reverse the malposition evident at surgery.
  
  
  RESULTS
  Preoperatively, 27 patients had symptomatic diplopia. Postoperatively, the diplopia resolved in 15 patients and decreased in 7. No patients had induced diplopia or exacerbation of preoperative diplopia. Enophthalmos resolved in 9 of 18 patients. Hypoglobus was normalized in nine of nine patients. There was one major complication of orbital infection requiring explantation 1 week postoperatively. Minor complications included undercorrection, a symptomatically palpable implant, and transient postoperative chemosis.
  
  
  CONCLUSIONS
  Porous polyethylene sheets offer several distinct advantages when used for orbital reconstruction. They are easy to handle, shape, contour, position, fixate, and use with other autogenous and alloplastic implants. In this series, these sheets permitted predictable, stable results with few complications.
authors.affiliation: Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston.
authors.forename: P A
authors.initials: PA
authors.lastname: Rubin
authors.forename: J R
authors.initials: JR
authors.lastname: Bilyk
authors.forename: J W
authors.initials: JW
authors.lastname: Shore
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000853:Anophthalmos / Q000601:surgery*; D001672:Biocompatible Materials; D015841:Enophthalmos / Q000601:surgery*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009915:Orbit / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D009917:Orbital Fractures / Q000601:surgery*; D011095:Polyethylenes; D011183:Postoperative Complications; D019736:Prostheses and Implants; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D001672:Biocompatible Materials; C084562:Medpor; D011095:Polyethylenes