Optic neuritis is inflammation of the optic nerve resulting in acute vision loss.
It most commonly affects women in their 20s and 30s.
Presentation:
- acute vision loss, usually unilateral
- pain worse on moving eye
- eye tender to touch
- loss of colour vision
Visual loss may become worse with fever (the Uhthoff phenomenon) but improves again afterwards.
Causes:
- demyelination due to MS - commonest cause
- infection - including herpes zoster, syphilis, TB, cat scratch disease, Lyme disease
- autoimmune - SLE, sarcoidosis, temporal arteritis
Investigation:
- fundoscopy - possibly optic nerve swelling (papillitis)
- MRI brain - looking for demyelination to help predict probability of MS
Treatment:
- IV methylprednisolone
- oral prednisolone is contraindicated as it increases rate of recurrence
Outcome:
- 90% recover 20/20 vision by 6 months
- 3% become blind
- 50% risk of developing MS within 15 years
References:
