Acute Orbital Inflammatory Syndrome and Vision Loss After Aminobisphosphonate Infusion.

Background: Aminobisphosphonates (AP) are used in the management of osteoporosis and Paget's disease because of their action as an inhibitor of bone resorption. Systemic and orbital inflammatory syndromes have been reported after infusion with AP medications, most commonly after intravenous (IV) zoledronate. Case Presentation: A 62-year-old male received COVID-19 and influenza vaccinations followed two days later by IV zoledronate infusion. The next day he developed flu-like symptoms followed two days later by right eye pain. An MRI showed right orbital enhancement prompting a short course of oral steroids. Two weeks later, he developed abrupt, severe visual loss accompanied by pallid disc edema. Despite treatment with high-dose intravenous steroids, vision failed to recover. Discussion: Blurred vision is common in AP-related orbital inflammation, but permanent vision loss is rare. In the few previously reported cases with optic nerve involvement, vision recovered with steroid treatment in all but one patient. In that case, and in our patient, the clinical features suggested an ischemic mechanism. In our case, the appearance of pallid disc edema more specifically pointed to inflammation of disc vasculature. Conclusion: This case serves to expand the clinical parameters of AP-associated orbital inflammation. The basis for our patient's worse visual outcome is unclear, perhaps related to preceding vaccination.