Retinal and choroidal microvascular embolism after intranasal corticosteroid injection

Two patients had uniocular visual loss after methylprednisolone acetate (Depo-Medrol) injection for control of chronic inflammatory conditions in the nose. The cause of the visual loss was embolic retinal and choroidal vascular occlusion. The emboli were presumably aggregates of microcrystals of methylprednisolone acetate.