Corneal abrasion

  • Etiology & Risk Factors:
    • Mechanical trauma (fingernail, branches, foreign body [FB]).
    • Contact lens (CL) wearers (predisposes to Pseudomonas aeruginosa).
  • Clinical Presentation:
    • Severe eye pain, foreign body sensation, photophobia, tearing, blepharospasm.
  • Diagnosis:
    • Visual acuity (VA): Must be assessed first before eye manipulation.
    • Fluorescein stain + cobalt blue light: Confirmatory (bright green epithelial defect).
    • Slit-lamp + eyelid eversion: Rule out retained subtarsal FB or stromal infiltrate.
    • Seidel test: Negative (if positive/streaming dye = open globe perforation).
  • Key Differentials:
    • Corneal ulcer (keratitis): Visible white stromal infiltrate ± hypopyon.
    • Herpes simplex keratitis: Dendritic (branching) ulcer.
    • Open globe: Peaked/teardrop pupil, flat anterior chamber, (+) Seidel test.
  • Management:
    • Non-CL wearers: Topical Abx (e.g., Erythromycin ointment, Polymyxin B/Trimethoprim drops).
    • CL wearers: Topical anti-pseudomonal fluoroquinolone (e.g., Ciprofloxacin, Ofloxacin); stop CL use immediately.
    • Analgesia: Oral NSAIDs; topical cycloplegics (e.g., cyclopentolate) for ciliary spasm/photophobia.
    • Tetanus prophylaxis: Update if dirty FB or trauma.
    • Contraindications (High-Yield):
      • NEVER patch the eye (promotes bacterial infection).
      • NEVER prescribe topical anesthetics for outpatient use (causes corneal toxicity/melting).
      • Avoid topical steroids (delays healing, exacerbates infections).
    • Ophthalmology referral: If symptoms persist/worsen after 24–48h, large central lesion, or corneal infiltrate develops.
  • Complications:
    • Bacterial keratitis / corneal ulceration.
    • Recurrent corneal erosion syndrome.
    • Corneal scarring with permanent visual loss.