Strategic Placement of Osseointegrated Implants in Orbital Exenteration Defects Prior to Postoperative Radiotherapy (PORT)

Objectives: To describe the management considerations that improve the likelihood of implant osseointegration and minimize the risk of osteoradionecrosis in orbital exenteration defects that are scheduled for PORT. Study Design: Retrospective case series Methods: Preoperative radiographic assessment of the malignancy is used to estimate the extent of resection and the likely clinical target volume (CTV) required for PORT. Interdisciplinary treatment planning between the surgeon, radiation oncologist, and maxillofacial prosthetist is employed to evaluate the optimal location for osseointegrated implantation. Implants were placed lateral to the midportion of the orbital defect when the proposed high-risk CTV contours were limited to the medial orbit. Implants were not inserted if the proposed highrisk CTV contours included the lateral portion of the orbit. Results: The CTVs could be acceptably contoured so that the lateral orbit would not receive high-dose radiation when there was limited tumor extension into the medial portion of the orbit and the orbital apex was free of malignancy. Conclusions: Careful interdisciplinary preoperative planning is essential to maximize implant success, minimize the risk of osteoradionecrosis, and optimize prosthetic rehabilitation.