Implants and spacers for paralytic ectropion: Literature review and assessment of a thin-profile porous polyethylene implant

Purpose: There is no ideal treatment paradigm for paralytic ectropion. This study evaluated lower eyelid spacers and the efficacy of a novel lower eyelid thin profile, bio?integratable, porous polyethylene. Methods: A retrospective review of 15 consecutive patients who underwent thin?profile porous polyethylene implantation and canthoplasty for paralytic ectropion was carried out. A comprehensive literature review of spacers for paralytic ectropion and retraction using the Pubmed database with search terms “[implant or graft or spacer] and [paralytic ectropion or paralytic retraction],” “graft and paralysis and ectropion,” “implant and paralysis and ectropion,” “graft and paralysis and retraction,” and “implant and paralysis and retraction” was carried out. Results: The mean patient age was 69 years (range: 50–88). Lagophthalmos improved from a mean of 5.7 mm (SD = 3.3, range 3–14 mm) to 1.4 mm (SD = 1.1, range 0–3.5 mm), P < 0.0001. MRD 2 improved from a mean of 6.7 mm (SD = 2.3, range 2–12 mm) to 4.2 mm (SD = 0.9, range 3–6 mm), P = 0.0005. No patients needed additional lower eyelid surgery. There were no implant exposures at a mean follow?up of 7.6 months (SD = 7.9, range 0.7–21.6 months). Detailed literature review revealed that hard palate and ear cartilage are the most reported spacers, each with unique disadvantages. Conclusion: The thin?profile porous polyethylene implant is a useful addition to the management of symptomatic paralytic ectropion. Meaningful comparison of lower eyelid spacers is difficult because of variations in surgical technique, spacer size, and poorly reported outcome data. No spacer proves superior

Cranioplasty with the Porous Polyethylene Implant(Medpor) for Large Cranial Defect

OBJECTIVE: This paper describes our experience and implant technique for cranioplasty of a large cranial defects using a porous polyethylene implant(Medpor) and compares the results with polymethylmethacrylate(PMMA). METHODS: Sixteen cranioplasties were performed using Medpor(n=10) and PMMA(n=6) implants between June 2003 and January 2005. The criterion for patient enrollment was a defect larger than 10cm in diameter. This study compared the operation times and complications. RESULTS: The operation times ranged from 105 to 250minutes(Mean 180 degrees +/-44minutes) in Medpor and from 185 to 460minutes (mean 128minutes) in PMMA. The absolute operation times were shorter using the Medpor implant and the differences were statistically significant(P=0.030). Satisfactory cosmetic results were obtained in all cases using the Medpor implant and with no implant-related complications. Bone ingrowth to the medpor implant was presumed to be the result on an increase in Houndsfield units of the implant, particularly at the marginal areas in the serial follow-up brain computed tomography images. CONCLUSION: It is believed that the properties of a Medpor implant make this implant an good alternative to the existing methods of a cranial contour correction. However, a further follow-up study will be needed.

The Use of Porous Polyethylene Implants (Medpor(R)) in Cross Pattern in Case of Extensive Blow Out Fracture

Implants are used in operative reconstruction of bony defect in case of blow-out fracture. If there is a large bony defect, the thin and flexible implants can not sustain intraorbital pressure, so it may be displaced. To prevent postoperative displacement of the implant, we tried reinforcing the center of the implant, where the intraorbital pressure was focused, piling up two pieces of porous polyethylene Implants(Medpor(R)) cross- shaped. 190 patients of large blow out fracture were divided into control group(n=95) who received classic orbital wall reconstruction and study group(n=95) to whom we inserted two small pieces of Medpor(R) one by one and covered a large defect cross shaped. We compared two groups in operative time, duration of postoperative accommodation and re-operation number. Operative time was assessed as shorter in study group(16.73+/-4.24min vs 21.40+/-5.32min, p> or =0.01). Duaration of postoperative accommodation also assessed as shorter in study group (2.05+/-0.70 weeks vs 3.00+/-1.00 weeks, p> or =0.01). There was no specific difference between two groups for re- operation number (3 vs 3, p=1.00). The method to insert two small pieces of Medpor(R) one by one and covered a large defect cross shaped shows shorter operative time and duration of postoperative accommodation than the classic method inserting large one piece of Medpor(R).