Classic presentation of optic neuropathy
☝painful ( with eye movements) decreased visual acuity
☝central or centrocecal visual field defect
☝abnormal color vision (dyschromatopsia)
☝a relative afferent pupillary defect.
☝optic disc changes may or may not be present ( depending on the portion of the nerve affected)
☝with or without normal fundus
causes of Optic neuritis
☝demyelinating disease ( MS)
☝autoimmune disease( SLE)
☝inflammatory disease ( sarcoidosis)
☝infections ( Lyme and syphilis)
Value of MRI of the orbits and brain
☝confirm the presence of optic nerve inflammation( increased enhancement)
☝assess for white matter lesions ( preiventricular white matter ( corpus callosum)
☝exclude other causes of optic neuropathy.
☝best MRI to be ordered
• T2 weighted with fat suppression
• FLAIR ( fluid attenuation inversion recovery)
The 10-year risk of developing MS
☝> 50% in optic neuritis patients with positive MRI results ( one or more white matter lesion)
☝< 20% in those with Free MRI ( no white matter lesions) .
Best Treatment of optic neuritis according to ONTT
(1 g daily) for 3 days
☝oral prednisone (1 mg/kg per day) for the following 11 days ( without gradual withdrawal)
Results of treatment
☝faster recovery of vision with the same final VA results with placebo
☝decreased risk of developing MS in the 2 years following treatment.
☝oral steroids alone are not indicated as it increases the rate of recurrent attacks of ON and does not decrease the risk of developing MS in 2 yrs following treatment.