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What is All are true regarding optic neuritis, EXCEPT: and explain in detail?
Optic neuritis is inflammation and demyelination of optic nerve. Electroretinogram is therefore not abnormal in optic neuritis. Ref: Parson's Diseases of the Eye, Page 114 ; Comprehensive Ophthalmology By A K Khurana, 4th Edition, Pages 294-5, 488-9