Optical Coherence Tomography Angiography in Chiasmitis

A 29-year-old girl presented complaining of acute bilateral visual loss associated with mild headache and retrobulbar pain. She was diagnosed with chiasmal optic neuritis caused by multiple sclerosis. Her visual acuity and visual field defect promptly improved after steroid therapy. However optical coherence tomography angiography showed a progressive reduction of superficial capillary plexus density of the retina and optic nerve consistent with the progressive impairment of the retinal ganglionar cell layer. Contrary to chiasmal compression, in chiasmal optic neuritis, the superficial capillary plexus density reduction is diffuse and does not reflect the peculiar anatomy of the chiasm.