Sudden Loss of Vision (Unilateral) - Central Field Defect

Is this optic neuritis?

Indications:

• Patient usually young and female.
• Onset usually sudden, but may get progressively worse over a two-week period, and then improves over the next four to six weeks.
• Often described as a central black blob in the vision.

What do I find?

• There will be a central field defect.
• There will be a RAPD.
• The optic disc is swollen in one third of cases
  (Look closely at the macula to ensure that there is no haemorrhage there).  

What do I do?

• The patient should be referred soon. There is a significant risk that the patient is developing multiple sclerosis – check neurology.

Is this wet/haemorrhagic age-related macular degeneration (AMD)?

Indications

• Usually older patient.
• May have long history of gradual mild blurring of vision (pre-existing dry AMD).
• Often begins with distortion followed by rapid reduction of vision associated with a macular haemorrhage.
• Peripheral vision is normal.

What do I find?

• Visual acuity is reduced.
• There may be a significant haemorrhage at the macula.

What do I do?

• If the patient has a large macular haemorrhage, the prognosis is poor. If there is no haemorrhage or limited haemorrhage, the patient may be eligible for photodynamic therapy. These patients should be referred immediately via letter to the nearest photodynamic therapy (PDT) service for assessment. If the diagnosis is uncertain the patient should be assessed at eye casualty.