Approach to Flashes, Floaters, Spots

Key Points 

  • Scintillating or colorful lights/spots, especially bilateral, are likely due to migraine; very rare for RD or PVD to occur simultaneously and bilaterally. 
  • Ask if visual phenomenon still present when patient closes each eye. Example: Patient reports symptoms in left eye, but they may actually be seeing in left visual field of right eye Classic retinal detachment: sudden new floaters, flashes of light, and “curtain coming down” over vision. Classic posterior vitreous detachment: sudden new floaters preceded by peripheral or crescentshaped flashes of light 
  • History is key: patient should have a reason for retinal detachment, e.g. diabetic retinopathy, intraocular infection, trauma, etc.
  • Approach to a Red Eye 
    • A red ("injected”) eye occurs when the conjunctiva is vasodilated 

Dry Eye 

  • Trace diffuse injection, blurry vision that fluctuates, gritty sensation, clears with blinking 
     

Corneal abrasion, ulceration, or exposure keratopathy 

  • Unilateral, moderate to severe injection, may be diffuse or sectoral, pain, blurry vision, mucus discharge, history of poor blink rate, intubated/sedated status. 
     

Subconjunctival hemorrhage 

  • Patch of bright red, often with sharp borders. Due to ruptured conjunctival vessels in pts on anticoagulation or after Valsalva (e.g., vomiting). Will resolve spontaneously without intervention 
     

Allergic conjunctivitis 

  • Chemosis, mild to moderate injection, blurry vision, very itchy, watery discharge, hx of allergies/atopy 
     

Viral or bacterial conjunctivitis 

  • Moderate to severe injection, scattered subconjunctival hemorrhages or petechiae, itchy or burning/painful eyes. If viral, look for preauricular adenopathy or recent URI 
     

Acute angle closure glaucoma 

  • Severe eye pain with nausea/vomiting, rock-hard eye, mid-dilated and fixed pupil, blurry vision, halos around lights. May be triggered by medication use 
     

Uveitis, episcleritis, scleritis 

  • Eye pain, perilimbal injection (“ciliary flush”), blurry vision. May have history of autoimmune disease. Episcleritis vs scleritis can be difficult to discern. Scleritis may have a deeper, violaceous hue 
     

Endophthalmitis 

  • Eye pain, history of trauma or eye surgery, severe vision loss, history of immunocompromise and systemic infection (if endogenous) 
     

Carotid-cavernous fistula 

  • Engorged and tortuous conjunctival vessels, recent history of trauma, resistance to retropulsion (will meet resistance if trying to push on the globe posteriorly)
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