optic neuritis

Question 1

what are the causes of optic neuritis?

Answer 1

• MS
• DM
• syphilis

Question 2

what are the features of optic neuritis?

Answer 2

• unilateral decrease in visual acuity over hrs-days
• poor discrimination of colours, ‘red desaturation’
• pain worse on eye movement
• RAPD
• central scotoma

Question 3

how is acute optic neuritis managed?

Answer 3

• high-dose steroids

- recovery usually takes 4-6 weeks

Question 4

what is the prognosis for optic neuritis?

Answer 4

MRI: if >3 white matter lesions, 5 year risk of developing MS is ~50%

Question 5

A 40-year-old female presents to her GP complaining of blurred vision in her right eye. It has become progressively blurrier over the last week, and is associated with pain worse on eye movement. She also feels that colours are dimmer than they should be, and this is affecting her work as a graphic designer.

On examination, a relative afferent pupillary defect is detected. Ophthalmoscopy reveals an elevated optic disc, with blurred margins.

Which underlying condition is most likely to have caused this presentation?

Answer 5

MS

Optic neuritis is associated with relative afferent pupillary defect