A Cochrane review included 6 studies with a total of 750 subjects with optic neuritis. Four trials recruited patients with no history of prior attacks of optic neuritis in the affected eye. One trial included only patients with confirmed multiple sclerosis, the remaining trial included people with optic neuritis of unknown and demyelinating etiologies. Most trials included participants with onset of visual symptoms within 4 weeks.Two trials evaluated low dose oral corticosteroids , one trial evaluated low dose iv. corticosteroids across two treatment arms and two trials evaluated a higher dose of iv. corticosteroids. One three-arm trial evaluated low-dose oral corticosteroids and high-dose iv. corticosteroids vs. placebo. Trials evaluating oral corticosteroids compared varying doses of corticosteroids with placebo. In a meta-analysis of trials evaluating corticosteroids with total dose greater than 3000 mg iv., the RR of normal visual acuity compared with placebo was 1.06 (95%CI 0.89 - 1.27; one study, n=285) at 6 months and 1.06 (95% CI 0.92 to 1.22; one study, n=270) at one year. The RR of normal contrast sensitivity for the same comparison was 1.10 (95% CI 0.92 to 1.32; 2 studies, n=346) at 6 months follow up. The RR of normal visual field was 1.08 (95% CI 0.96 to 1.22; 2 studies, n=346) at 6 months and 1.02 (95% CI 0.86 to 1.20; 2 studies, n=316) at one year.
Comment: The quality of evidence is downgraded by inconsistency (heterogeneity in interventions and outcomes)