Epithelial defect of the cornea — acutely painful but usually heals within 24-72 hours; contact lens wearers need Pseudomonas coverage.
Also known as: corneal abrasion, corneal epithelial defect, traumatic corneal abrasion, contact lens-related corneal abrasion
Overview
Disruption of the corneal epithelium from mechanical trauma without full-thickness penetration. Common mechanisms include fingernail injuries (especially in parents of infants), tree branches and paper, foreign bodies (metal, glass, wood, plant matter), and contact lens-related trauma. Recurrent corneal erosion is a related condition in which a poorly healed abrasion repeatedly breaks down.
Epidemiology
Among the most common eye complaints in emergency and primary care. Higher incidence in young men, occupational settings (construction, grinding), contact lens wearers, and parents of small children.
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Question 1EENTMedium
A 45-year-old construction worker has severe right eye pain, redness, and decreased vision (visual acuity 20/60) after sustaining an eye injury at work. Fluorescein staining shows a linear corneal abrasion without infiltrate. Which of the following is the most appropriate treatment?
ATopical steroid drops
BTopical cycloplegic drops
COral cephalexin capsules
DEye patching with topical anesthetic
ETopical antibiotic drops
Reveal answer & full explanation
Correct answer: E — Topical antibiotic drops
ATopical steroid drops
BTopical cycloplegic drops
COral cephalexin capsules
DEye patching with topical anesthetic
ETopical antibiotic drops✓
Why Topical antibiotic drops is correct
A traumatic corneal abrasion is treated with prophylactic topical antibiotics (erythromycin ointment or polymyxin-trimethoprim) to prevent secondary bacterial keratitis while the epithelium heals
Contact-lens wearers receive an antipseudomonal fluoroquinolone (ciprofloxacin or ofloxacin)
Oral or topical NSAIDs provide pain control, and most abrasions re-epithelialize within 24-48 hours with a recheck at 24 hours
Why the others are wrong
Topical steroid drops — corticosteroids on an open epithelial defect delay re-epithelialization and raise the risk of secondary bacterial, fungal, and herpetic keratitis, so they are avoided in corneal abrasion; the harmful-topical trap
Eye patching with topical anesthetic — patching delays epithelial healing and outpatient topical anesthetics impair healing and mask injury, so both are avoided; the outdated-practice distractor
Oral cephalexin capsules — systemic antibiotics are unnecessary for an uncomplicated abrasion and do not deliver the high ocular-surface drug levels that topical therapy places directly on the defect; the over-escalation trap
Topical cycloplegic drops — tempting because ciliary spasm adds to the pain of a corneal injury, but cycloplegics have not been shown to improve pain or healing in an uncomplicated abrasion and are generally kept for traumatic iritis or marked photophobia; they also do nothing to prevent the bacterial keratitis that this open epithelial defect risks; the comfort-drop trap
Question 2EENTMedium
A 31-year-old man presents with acute severe pain, tearing, and a foreign-body sensation in the right eye that began an hour ago when his toddler scratched his eye with a fingernail. He keeps the eye tightly shut and reports marked light sensitivity. He does not wear contact lenses. On slit-lamp examination there is conjunctival injection and a sharply demarcated area of yellow-green fluorescein uptake under cobalt blue light, with no stromal infiltrate, hypopyon, or anterior chamber cells. Visual acuity is preserved, and the upper lid is everted with no retained foreign body. Which of the following is the most likely diagnosis?
AUltraviolet photokeratitis
BHerpes simplex keratitis
CPenetrating corneal laceration
DRecurrent corneal erosion
ETraumatic corneal abrasion
Reveal answer & full explanation
Correct answer: E — Traumatic corneal abrasion
AUltraviolet photokeratitis
BHerpes simplex keratitis
CPenetrating corneal laceration
DRecurrent corneal erosion
ETraumatic corneal abrasion✓
Why Traumatic corneal abrasion is correct
Acute painful red eye after a recognizable mechanical mechanism (fingernail trauma, classic in parents of small children) with a sharply demarcated epithelial defect that takes up fluorescein is the textbook presentation.
Disruption of the corneal epithelium exposes densely packed sensory nerves, producing intense pain, photophobia, tearing, and blepharospasm.
The absence of a stromal infiltrate, hypopyon, and anterior chamber cells/flare excludes bacterial keratitis and iritis; the upper lid was everted to rule out a retained subtarsal foreign body.
Why the others are wrong
Recurrent corneal erosion - also stems from prior fingernail or paper-cut abrasions (or epithelial basement membrane dystrophy), but it causes repeated episodes of sudden pain on waking, weeks to months after the original injury, when the poorly adherent epithelium tears away with lid opening; here the pain began at the moment of a fresh injury.
Herpes simplex keratitis - produces a branching dendritic ulcer with terminal bulbs and decreased corneal sensation, typically without an acute traumatic trigger; a sharply demarcated defect appearing immediately after a fingernail injury argues against it.
Ultraviolet photokeratitis - welding arcs, tanning beds, and snow or water glare cause a painful, photophobic keratopathy, but symptoms begin 6-12 hours after exposure, are usually bilateral, and fluorescein shows diffuse punctate epithelial staining rather than a single sharply demarcated defect; this is an immediate, unilateral, mechanical injury.
Penetrating corneal laceration - a sharp fingernail injury with intense pain can raise concern for an open globe, but a full-thickness laceration typically shows a positive Seidel sign (aqueous streaming through the fluorescein), often with a shallow anterior chamber, a peaked pupil, or reduced acuity; a toddler's fingernail is a low-energy tangential scratch, and here acuity is preserved and fluorescein outlines a sharply demarcated epithelial defect.
Additional high-yield points
A stromal infiltrate, hypopyon, or contact lens wear points instead to bacterial keratitis (contact lens-related abrasions need antipseudomonal topical coverage and no patching), and anterior chamber cells with ciliary flush point to iritis.
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Mechanical disruption of the corneal epithelium exposes sensory nerves (cornea is the most densely innervated tissue in the body), producing intense pain and photophobia. Healing occurs by sliding of adjacent epithelial cells within hours and mitosis over 24-72 hours, with reformation of hemidesmosomes attaching epithelium to basement membrane over weeks. Inadequate hemidesmosome formation predisposes to recurrent erosion. Organic or plant-matter trauma raises risk for fungal keratitis; contact lens wearers and trauma involving soil or vegetation raise risk for Pseudomonas and Acanthamoeba keratitis.
Recurrent erosion — pain on awakening with eyelid opening, recurring weeks to months after initial injury
Signs / physical exam
Conjunctival injection
Fluorescein staining of the epithelial defect under cobalt blue light — yellow-green uptake of denuded area
Foreign body visible on lid eversion or in the inferior fornix — always evert upper lid for vertical scratches
Seidel sign (positive in full-thickness corneal injury): fluorescein dye streaming down from a leaking aqueous source — indicates globe penetration, NOT an abrasion
No stromal infiltrate or hypopyon — these suggest keratitis
Classic findings
Acute painful red eye after recognizable trauma with fluorescein uptake of an epithelial defect.
Differential diagnosis
Corneal foreign body — Persistent foreign body sensation; visible particle on slit-lamp; remove with sterile needle/burr
Microbial (bacterial) keratitis — Contact lens wearer (often overnight wear; Pseudomonas) with severe pain, photophobia, reduced vision, and ciliary flush; white stromal infiltrate or ulcer ± hypopyon and mucopurulent discharge; immediate ophthalmology for culture and intensive topical fluoroquinolone; never patch, no steroids initially
Herpes simplex keratitis — Dendritic ulcer with terminal bulbs, decreased corneal sensation; topical/oral antivirals; NO patching, NO steroid
Recurrent corneal erosion — Recurrent episodes of pain on awakening; map-dot-fingerprint dystrophy or prior trauma; bandage lens, lubricant ointment
UV photokeratitis (welder's flash) — Bilateral severe pain 6-12 hours after UV exposure (welding, snow); punctate staining; supportive care
Chemical injury — Exposure to acid/alkali; alkali far worse; immediate copious irrigation > 30 min, check pH, ophthalmology
Culture/scrapings if appearance suggests infectious keratitis (infiltrate, contact lens-related, atypical)
Imaging
Slit-lamp examination with fluorescein staining — primary diagnostic tool
Visual acuity before and after exam
Lid eversion (upper lid) to exclude retained foreign body — mandatory when vertical linear staining is present
Seidel test if globe injury possible
Topical anesthetic (proparacaine, tetracaine) is essential to allow examination; never prescribe for home use — causes corneal toxicity, melt, perforation
CT orbits if intraocular foreign body suspected (history of grinding/metal, hammering, gunshot)
Diagnostic algorithm
Scenario
Antibiotic Choice
Patch?
Special Considerations
Simple non-contact-lens abrasion
Erythromycin ointment, polymyxin/trimethoprim, or sulfacetamide
Oral doxycycline + topical steroid pulse for stubborn cases
Corneal abrasion management — choice of antibiotic and adjuncts by scenario.
Treatment
First-line
Topical ocular antibiotic — choice depends on contact lens use:
• NON-contact-lens wearers: erythromycin ointment QID, polymyxin/trimethoprim drops, sulfacetamide 10% drops, or bacitracin ointment × 3-5 days
• CONTACT LENS wearers (or trauma with organic/plant matter): fluoroquinolone with Pseudomonas coverage — ciprofloxacin 0.3%, ofloxacin 0.3%, moxifloxacin 0.5%, or gatifloxacin 0.5% — 1-2 drops QID for 3-5 days or until healed (hourly dosing is for keratitis, managed by ophthalmology)
Oral or topical NSAIDs (ketorolac 0.5% drops or oral ibuprofen) for analgesia
Acetaminophen or short course of oral opioid for severe pain in selected patients
Cycloplegic (cyclopentolate 1%, homatropine 5%) for ciliary spasm and photophobia in larger abrasions
Update tetanus status only if abrasion is contaminated with soil or organic material (very rarely needed for clean abrasions)
Discontinue contact lens wear until healed AND symptom-free for several days
Second-line / adjunct
Do NOT patch contact lens-associated abrasions or vegetative-matter abrasions — increases Pseudomonas risk
Pressure patching of simple non-contact-lens abrasions has no proven benefit and is no longer routinely recommended
Topical anesthetic should NEVER be prescribed for outpatient use — causes corneal melt and persistent epithelial defects
Re-examine within 24 hours for larger abrasions, contact lens-related, or symptoms worsening
Immediate same-day ophthalmology referral for a corneal infiltrate or ulcer (culture and intensive topical antibiotics), hyphema or hypopyon, or suspected globe penetration; recheck or ophthalmology referral within 24 hours for large (>4 mm) or central abrasion, contact lens-related abrasion, decreased vision, or no improvement in 24-48 hours
Complications
Bacterial keratitis / corneal ulcer (especially in contact lens wearers — Pseudomonas can perforate the cornea within 24 hours)
Recurrent corneal erosion
Corneal scarring with permanent visual impairment if central
Endophthalmitis if penetrating injury missed
Misdiagnosis of herpes simplex keratitis as abrasion (dendrites may be subtle)
Topical anesthetic abuse → corneal melt
PANCE pearls
Always evert the upper lid in any patient with a corneal abrasion — retained subtarsal foreign bodies cause vertical linear stains and persistent pain.
Contact lens wearers get Pseudomonas coverage (fluoroquinolone), and they do NOT get patched.
Topical anesthetics are diagnostic, not therapeutic — never prescribe for home use.
An infiltrate or hypopyon (especially in a contact lens wearer) is keratitis, not an abrasion — immediate same-day ophthalmology referral to culture and treat as a corneal ulcer.
Vegetative-matter trauma (branch, hay) raises risk for fungal keratitis; soil contamination raises risk for Acanthamoeba in lens wearers using tap water.
Seidel-positive injury, hyphema, or distorted iris/pupil = globe penetration — shield (don't patch), avoid pressure, IV antibiotics, urgent surgical consultation.
References
AAO 2018 — American Academy of Ophthalmology. Bacterial Keratitis Preferred Practice Pattern. Ophthalmology 2019;126(1):P1-P55
Cochrane 2016 — Lim CH et al. Patching for corneal abrasion. Cochrane Database Syst Rev 2016;7:CD004764
Wilson 2004 — Wilson SA, Last A. Management of corneal abrasions. Am Fam Physician 2004;70(1):123-128
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