Customized Polyethylene Implant for the Reconstruction of the Orbital Roof and Lateral Orbital Wall in Orbitozygomatic Craniotomies

Introduction: The orbitozygomatic craniotomy (COZ) provides excellent exposure of the orbit, parasellar structures, and both anterior and middle cranial fossae. It is done with either one or two pieces. In both methods the superolateral aspect of the orbit is fractured and the deeper respective margins are often rongeured. Poor cosmetic result or pulsatile exophthalmos or enophthalmos arise from suboptimal orbital reconstruction. We have devised a customized porous polyethylene implant intended for the reconstruction of the orbital roof and lateral margin following COZ.

Methods: This is a retrospective review of 320 consecutive patients who underwent COZ for skull base tumors and aneurysms at Saint Louis University Hospital from January 2005 to January 2008. Asymmetry, ptosis, and contour deformity as assessed by the patients and by ratio estimation scale technique (REST) for symmetry and visual analog scale (VAS) classified cosmetic results as good, suboptimal, or poor. Patients were seen in follow-up on at least two occasions, 3 and 6 months postoperatively. Suboptimal cosmetic result demonstrated at least one objective flaw involving the three parameters. Poor result uses the same criteria as the former with an additional assessment by the patient of disfigurement. Good result entails overall satisfaction by the patient with no objective flaws.

Results: Of the 320 operations, 62% were for skull base tumors and 38% for vascular lesions. Among the tumors, 70% were meningiomas, 20% were craniopharyngiomas, the remainder included suprasellar, pituitary tumors, epidermoids, dermoids, and chordomas. The vascular lesions included aneurysms (anterior and posterior circulations) and arteriovenous malformations. Over 95% of patients were satisfied with good results. There were 4% with suboptimal cosmetic result and only < 1% had poor cosmetic outcome. Patients' satisfaction correlates well with objective measurements scales used.

Conclusion: Good cosmetic result from reconstruction of the superior and lateral orbital walls following COZ can be achieved by our customized porous polyethylene implant in more than 95% of cases with no significant complication related to the implant.