10 Can’t Miss Diagnoses of the Red Eye

  • Acute angle-closure glaucoma (AACG)
  • Bacterial keratitis/ulcer
  • Endophthalmitis
  • Hyphema
  • Hypopyon
  • Iritis
  • Infectious keratitis (bacterial and viral)
  • Orbital cellulitis
  • Scleritis
  • Uveitis

A brief differential for a PAINFUL red eye based on symptom description**:**

  • Itching => allergies
  • Burning => lid disorders, dry eye
  • FB sensation => FBcorneal abrasion
  • Localized lid tenderness => hordeolumchalazion
  • Deep, intense pain => corneal abrasionscleritisiritisacute glaucomasinusitis, orbital cellulitis
  • Photophobia => corneal abrasionsiritisacute glaucoma (think about ciliary body muscle spasm or other problems from the anterior segment of the eye)
  • Halo vision => acute glaucomauveitis (resulting from corneal edema)

A brief differential for a PAINLESS red eye based on location**:**

  • Diffusely red: conjunctivitis or episcleritis, but also consider eyelid abnormalities that may have an associated conjunctivitis (e.g., blepharitisectropionentropion, eyelid lesion like tumor or stye)
  • Localized redness: subconjunctival hemorrhagepterygiumcorneal foreign body (usually painful), ocular trauma (usually painful)