Optic nerve thickening and infarction as the first evidence of orbital involvement with mucormycosis.

We report a 53-year-old female with uncontrolled diabetes mellitus who presented with decreased vision in the right eye for a few hours duration. Orbital computed tomography and magnetic resonance imaging were performed at presentation and showed a thickening and infarction of the right optic nerve with no other orbital abnormalities. A few days later, the patient developed necrosis in the region of the right medial canthus and nasal mucosa. Tissue biopsy confirmed the diagnosis of mucormycosis.