see also:

• ophthalmology
• Eye injuries
• diplopia / double vision
• color blindness / color vision deficiency

• acute non-traumatic blurred vision is a relatively common presentation to ED
• patients may use the term blurred vision to cover a number of different symptoms such as:
  • actual decreased acuity
  • transient visual loss (eg. amaurosis fugax)
  • “double vision”
  • photopsia (flashes of light as occurs in migraine aura, retinal detachment, occipital lobe infarction, etc)
  • floaters
  • visual field defect
  • watery eyes
• patients should be explicitly evaluated to exclude an time-critical ocular emergency such as:
  • acute glaucoma
  • retinal detachment - may have photopsia, visual field defect, floaters
  • retinal artery occlusion (RAO)
  • endophthalmitis
  • occipital stroke
  • temporal arteritis - high ESR or CRP with tender scalp artery - consider biopsy and high dose steroids ASAP
• other causes which should be considered but are not as time critical include
  • RVO - no ED Rx currently available
  • optic neuritis

• flashes of light
• may be caused by pathologic stimulation of the retina and production of phosphenes

• retinal detachment
• posterior_vitreous_detachment
• migraine
• occipital stroke
• sensory deprivation (ophthalmopathic hallucinations)

• sudden onset of large floaters in the center of the visual axis may indicate posterior_vitreous_detachment (PVD)
  • circular floater when the vitreous detaches from its annular ring surrounding the optic nerve
• hundreds of tiny black specks is suggestive of a vitreous hemorrhage, resulting from disruption of a retinal vessel caused by a retinal tear or mechanical traction of a vitreoretinal adhesion
  • a few hours later, cobwebs may develop due to formatio of irregular blood clots

• retinal detachment
• migraine
• occipital stroke

• vitreous haemorrhage
  • haemorrhage from macular degeneration
• central retinal artery occlusion
• central retinal vein occlusion
• retinal detachment
• optic neuritis
• internal carotid artery occlusion

• acute glaucoma
• endophthamitis
• uveitis
• keratoconus acute deterioration

• painless transient visual loss due to reduced blood flow to the eye - may be both eyes or one eye
• amaurosis fugax preceding persistent loss of vision suggests branch retinal artery occlusion (BRAO) or temporal arteritis
• consider transient smartphone blindness due to only using one eye to look at smartphone in dark bedroom resulting in transient blindness while both eyes take time to adjust to a subsequent change in ambient lighting