A patient with optic neuritis may developed distorted color vision (dyschromatopathis).

Patient selection: optic neuritis, including multiple sclerosis


Koellner's rule: most patient with optic neuropathy have defect in red/green discrimination. However, there are many exceptions including demyelinating optic neuritis. No single type of color defect is found consistently with optic neuritis.


Red/Green Defect

Blue/Yellow Defect

Visual Acuity

Classification of Verriest


none or minimal

reduced central visual acuity

I (protan like)


present, less severe


II (deutan like)

none or minimal

mild or moderate

normal or mildly reduced

III (tritan like)


In addition the patterns reported by Verreist, nonselective defects can also occur.


The defect in color vision can change over time both in colors affected and severity.

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