All are true regarding optic neuritis except:
Electroretinogram indicates the activity of retinal (esp. rods & cones) function and has no role in assessing the functional integrity of the optic nerve. So it can&;t be abnormal in optic neuritis. Ref: AK khurana 7th ed.
Decreased visual acuity
Decreased pupillary reflex
Abnormal electroretinogram
Abnormal visual evoked response retinogram
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