Typical optic neuritis associated with MS causes vision loss over hours to days, with the nadir approximately 1 week after onset. Visual loss may be subtle or profound. Usually unilateral, rarely bilateral. Age typically 18 to 45 years. Retro-orbital pain, especially with eye movement. Acquired loss of color vision. Reduced perception of light intensity. May have other focal neurologic symptoms (e.g., weakness, numbness, tingling in extremities). May have antecedent flulike viral syndrome. Occasionally altered perception of moving objects (Pulfrich phenomenon) or a worsening of symptoms with exercise or increase in body temperature (Uhthoff sign).
More recently, immune-mediated disorders of the CNS, such as neuromyelitis optica spectrum disorder (NMOSD), have been described as causes of atypical optic neuritis. Atypical features include advanced patient age, severe vision loss with poor recovery, and simultaneous or rapidly sequential bilateral optic neuritis.
Critical
Relative afferent pupillary defect in unilateral or asymmetric cases; decreased color vision; central, cecocentral, or arcuate visual field defects.
Other
Swollen disc (in one-third of patients) usually without peripapillary hemorrhages (papillitis most commonly seen in children and young adults) or a normal disc (in two-thirds of patients; retrobulbar optic neuritis more common in adults). Posterior vitreous cells possible.
Typical Optic Neuritis
If patient seen acutely with no prior history of MS or optic neuritis:
NOTE: |
The Optic Neuritis Treatment Trial (ONTT) found steroid treatment reduced initial progression to clinically definite multiple sclerosis (CDMS) for 2 years. Steroid therapy only increases the rapidity of visual return but does not improve final visual outcome. |
NOTE: |
NEVER use oral prednisone as a primary treatment because of increased risk of recurrence found in ONTT. Disease-modifying drugs as listed above have been shown to reduce probability of progression to CDMS in high-risk patients. |
In a patient with a diagnosis of prior MS or typical optic neuritis:
Atypical Optic Neuritis
NMOSD (anti-AQP4 positive, anti-MOG positive, or seronegative disease):
Diagnosis of Prior MS or Typical Optic Neuritis
Atypical Optic Neuritis
NMOSD: Even closer follow up initially may be necessary due to frequency of relapses and severity of vision loss. Follow up within 2 weeks of initial treatment with rapid referral to neurologist experienced in treating NMOSD.