Sudden Painless Visual Loss

A sudden onset of visual loss is alarming to the patient. The diagnosis can be made in
most cases by a careful history and eye examination without immediate recourse to the
ophthalmologists, however, this may well be required. Only a few diagnosis require
immediate ophthalmic referrals for management:

  • central or branch retinal artery occlusion of less than 6 hours
  • any sudden visual loss of less than 6 hours and the cause can not be established
  • giant cell arteritis
  • All other causes of visual loss can be referred within 24 hours.
    • Transient visual loss like a 

    • curtain coming down (suggestive 
      of amourosis fugax)
    • Visual loss or field loss preceded

    • by sudden onset floaters and flashing 
      light (photopsia), this is suggestive of 
      retinal detachment
    • History of poorly controlled diabetes 

    • mellitus and laser treatment to the 
      retina (vitreous haemorrhage)
    • Headache +/- jaw claudication (pain 

    • in the jaw on eating) in the elderly 
      (giant cell arteritis)
    • Pain on eye movement in young patients 

    • (optic neuritis)
    • Visual acuity 
    • Assess the visual field by confrontation, 

    • some patients may have homonymous 
      hemianopia and yet complain of uniocular 
      visual loss.
    • Full ocular examination which should 

    • include:
      • pupil reaction for afferent pupillary

      • defect (this occurs in optic nerve
        disorder and extensive retinal
      • retinal examination for any obvious 

      • signs
    The following are the most common causes of sudden visual loss seen in the casualty: