Rhinocerebral Mucormycosis of the Optic Nerve.

A 55-year-old man initially presented with progressive right-sided vision loss during hospitalization following revision liver transplant. He underwent treatment with high-dose corticosteroids for presumed optic neuritis, with initial vision improvement that subsequently progressed to complete visual loss. He was then transferred to our facility. Repeat radiographic analysis demonstrated left maxillary sinus disease, enhancement of the right orbital apex, and enlargement of the optic nerve without associated sphenoid mucosal disease (Figure 1A, B). Due to his history of immunosuppression and the diagnostic dilemma, we elected to explore his left nasal cavity and paranasal sinuses, where necrotic tissue was discovered within the middle meatus and maxillary sinus. Given this finding, along with the presence of his right-sided vision loss and the findings on imaging, his right nasal cavity and sphenoid sinus were examined. This revealed an ulcerative lesion of the optic nerve (Figure 1C). Based on pathologic analysis of this lesion, along with the contents from his left-sided surgery, he was diagnosed with invasive fungal sinusitis (Figure 1D). Fungal polymerase chain reaction identified Rhizopus oryzae as the causative organism. His treatment was multimodal, consisting of antifungal therapy and limiting immunosuppression. At 4-month follow-up, he was alive without disease, but his vision did not return. This study was approved by the Colorado Multi-institutional Review Board (13-1555).