Corneal abrasion
A corneal abrasion is a traumatic or foreign-body-related defect of the corneal epithelium diagnosed by fluorescein uptake under cobalt-blue light. Uncomplicated cases heal in days with lubrication and pain control, but contact-lens wear mandates antipseudomonal coverage and any red flag (rust ring, infiltrate, Seidel sign, hypopyon) demands same-day ophthalmology referral.
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What this article covers
- Overview
Traumatic epithelial defect: a corneal abrasion is a disruption of the corneal epithelium from mechanical trauma, a retained or transient foreign body, or contact lens use, without extension into the underlying stroma.
- Epidemiology
A frequent cause of acute eye complaints: mechanical trauma and foreign bodies are among the leading causes of the "red eye" presentation seen in primary care and emergency settings.
- Risk factors
Ocular or periocular trauma: direct mechanical contact from a fingernail, branch, makeup applicator, sports equipment, or airbag deployment.
- Pathophysiology
Mechanical disruption of the epithelial basement membrane: shear or direct trauma strips corneal epithelial cells, exposing the underlying basement membrane and superficial nerve endings.
- Clinical features
Foreign-body sensation: the hallmark symptom, a gritty or scratchy feeling present at rest and made worse with each blink.
- Differential diagnosis
Globe laceration/penetrating injury: visual deficit, globe deformity, teardrop-shaped pupil, vitreous leakage, and a positive Seidel sign (fluorescein clearing as aqueous leaks out); avoid globe…
- Diagnosis
Clinical diagnosis confirmed by fluorescein staining: instill fluorescein dye and examine under cobalt-blue (Wood's lamp) light; the denuded basement membrane takes up dye and fluoresces green, confirming the defect and its size/shape.
- Management
First, apply topical anesthetic to facilitate the exam: permits visual acuity testing, slit lamp exam, and foreign body removal; for in-office use only, never prescribed for the patient to take home.
- Complications
Corneal ulcer/infectious keratitis: bacterial superinfection, particularly with Pseudomonas aeruginosa in contact lens wearers, with escalating pain, opacification, or a central ulcer; needs urgent…
- Prognosis
Excellent for an uncomplicated abrasion: most small abrasions in non-lens wearers re-epithelialize within 3-5 days with full symptom resolution and no visual sequelae.
- Prevention
Protective eyewear during high-risk activities: safety glasses or goggles for grinding, hammering, metal shaving, machine shop work, and yard work, high-risk mechanisms for both abrasion and penetrating globe injury.
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