Osteoradionecrosis of the lamina papyracea leading to recurrent orbital infections-A case study.

Osteoradionecrosis (ORN) is a well-known complication of radiotherapy (RT) to the sino-nasal cavity and nasopharynx. Here, we report a case of recurrent orbital infections secondary to ORN of the lamina papyracea (LP). A 66-year-old female presented to our unit with right periorbital swelling and pain after having undergone chemotherapy and proton beam irradiation to her ethmoid sinuses for sino-nasal undifferentiated carcinoma (SNUC) 5 years prior. She had also undergone endoscopic sinus surgery for chronic rhinosinusitis about a year prior to the current presentation. Her post-operative course was notable for recurrent episodes of pre-septal cellulitis occurring about 3 months apart that were increasingly severe. Examination revealed right proptosis, and endoscopy showed an exposed and denuded LP with scant crusting of the ethmoid sinuses. Microbial studies did not yield any significant growth, and imaging showed enhancement of the right orbit. The working diagnosis was acute right orbital cellulitis secondary to ORN of the right LP. She was treated with broad spectrum intravenous antibiotics and systemic steroids, but experienced minimal symptomatic improvement. She then underwent endoscopic resection of the right LP, and histopathological examination showed osteonecrosis on an inflammatory background. Post-operatively, all orbital symptoms resolved and she was well at 6 months' follow up. In the discussion, we highlight additional factors in our patient that may have contributed to this clinical presentation, and hope that this report raises awareness of a rare complication of RT to the sino-nasal cavity.