Corneal Abrasion, Foreign Body & Chemical Eye Injury

See Ophthalmic Trauma for blunt trauma, open globe injury, orbital compartment syndrome, orbital fracture and lid lacerations.

Assessment

Instil topical anaesthetic before examining a painful eye — the cornea is densely innervated and pain is often out of proportion to the size of the injury. Check visual acuity, then stain with fluorescein under cobalt blue light. The staining pattern is informative: a single linear defect suggests a simple abrasion; multiple linear defects suggest a foreign body trapped under the eyelid (“ice rink” sign) and should prompt lid eversion; punctate staining suggests keratitis (chemical, infectious or UV); a dendritic pattern suggests herpetic disease, often with no history of trauma.

Always evert the eyelid to exclude a retained foreign body: ask the patient to look down, grasp the upper lashes with your non-dominant hand and pull slightly away from the globe, then use a cotton bud in your dominant hand to fold the lid up over the tarsal plate. Lower lid eversion is done by gently pulling the lid down.

Corneal ulcer

The diagnosis not to miss. A corneal ulcer is a full-thickness breach of the epithelium into the underlying stroma, not just the surface — a much more serious injury than an abrasion, with a real risk of scarring, perforation and permanent vision loss.

Features favouring ulcer over simple abrasion:

• Severe pain, conjunctival injection and reduced vision (an abrasion is not typically accompanied by all three)
• A white/dense infiltrate visible on the cornea without fluorescein — an abrasion should not show this
• Hypopyon (pus layering in the anterior chamber)
• Contact lens wear, especially with swimming, showering, or sleeping in lenses — the major risk factor for Pseudomonas keratitis, which can progress from first symptoms to endophthalmitis within days
• Symptom onset over days rather than immediately after an injury

Any suspected corneal ulcer needs urgent ophthalmology referral — trauma-related ulceration (especially with possible perforation or an intraocular foreign body), chemical injury, and any suspected infectious keratitis. Remove contact lenses before referral, and do not start empirical antibiotics or steroids first — this confounds the corneal scrape ophthalmology needs to direct treatment. An abrasion that has not healed within a couple of days also needs urgent ophthalmology review, not routine primary care follow-up.

Corneal abrasion

A defect limited to the corneal epithelium — the commonest eye injury seen in general practice and urgent care. Causes include fingers/fingernails, paper, tree branches, contact lenses, blown dust or sand, and sport (ball sports account for over half of sport-related eye injuries in Australian data). Symptoms typically start within 24–48 hours, usually immediately; a longer or delayed onset raises suspicion for a retained foreign body or another complication.

Management:

• Oral analgesia (paracetamol or an NSAID) is first line; there is no good evidence topical NSAID drops do better than oral, at added cost
• Topical antibiotic (chloramphenicol) is standard practice for 1 week, though the evidence that it prevents infection in a non-contact-lens wearer is weak. Contact lens wearers are the exception — they carry a real Pseudomonas risk and need an antipseudomonal cover; discuss the choice with a pharmacist or ophthalmology rather than defaulting to chloramphenicol, and keep the patient out of lenses until healed
• Do not patch — trial evidence (including a Cochrane review) found no benefit for pain or healing time, and some studies found patched abrasions healed worse
• Do not prescribe take-home topical anaesthetic — it is for examination only. Continued use inhibits epithelial healing and can cause corneal melt; this remains the position of Australian ophthalmology despite some emergency-medicine literature arguing very short courses are safe
• Cycloplegia (e.g. cyclopentolate) is sometimes used for associated ciliary spasm, but trial evidence does not show it reduces pain
• Corticosteroids are not indicated
• Uncomplicated abrasions heal within 24–48 hours; review in 24–48 hours with primary care. Refer to ophthalmology instead if: suspected penetrating injury, contact lens wearer, cold sore history or a dendritic lesion (herpetic disease), reduced visual acuity or a large/central abrasion, or signs of infection (white infiltrate, persistent pain, a non-healing defect)

Corneal foreign body

1. Topical anaesthetic, then evert the lid ± sweep with a moistened cotton bud — a linear (“ice rink”) staining pattern suggests a subtarsal foreign body hiding under the upper lid
2. Fluorescein to confirm the defect and check for a Seidel sign (a “waterfall” or diluted streak of fluorescein under cobalt blue light) — a positive Seidel sign means a full-thickness/open globe injury: stop, do not attempt removal, and refer urgently (see the Ophthalmic Trauma page’s Open globe section)
3. If Seidel-negative, attempt removal starting with the least invasive technique and escalating only if needed: irrigation first, then a moistened cotton bud, then (under slit lamp magnification if available) a fine needle held parallel to the corneal surface with the bevel facing away from the eye — never point a needle directly at the eye
4. Re-stain and re-confirm Seidel-negative after removal
5. Topical antibiotic (as for corneal abrasion above) and review in 24–48 hours

Rust ring. An iron-containing foreign body can leave a rust ring within hours. It does not need to be removed at the same sitting — deferring removal 24–48 hours (to an ophthalmology follow-up) makes it easier to remove, as it becomes more superficial as inflammatory cells push it toward the surface, and outcomes are similar either way. Removal (by burr or needle) carries a real risk of scarring and corneal perforation and is better left to whoever is doing the ophthalmology follow-up unless there is local experience and equipment (slit lamp, corneal burr) to do it safely at first presentation.

Refer to ophthalmology for: a residual rust ring, incomplete removal, multiple foreign bodies, a foreign body in the visual axis, or any high-risk mechanism (grinding metal on metal, high-velocity projectile) — these carry a much higher risk of an occult intraocular foreign body or globe rupture and should be examined with a low threshold for imaging.

Chemical eye injury

Do not delay irrigation to take a history. Alkaline substances (e.g. caustic soda, cement, plaster) penetrate deeper and are more damaging than acidic agents.

1. Check pH of both eyes with universal indicator paper in the conjunctival fornix
2. Topical anaesthetic, then irrigate copiously with 0.9% saline or a balanced salt solution — manual flush, a saline bag, or an IV giving set on full flow; tap water under a running tap if nothing else is available, directed from the nose toward the ear so the other eye is not contaminated
3. Evert the lids to flush and sweep the fornices for any particulate matter (lime, cement)
4. Recheck pH 5 minutes after stopping irrigation; continue until it normalises to 7.0–7.4, with no volume limit
5. Once normalised, assess with fluorescein: epithelial defects, loss of conjunctival/limbal vessels, lid involvement, visual acuity
6. Post-irrigation: topical chloramphenicol QID for 1 week plus intensive lubrication; review every 1–2 days

Roper-Hall classification:

Grade	Corneal involvement	Limbal involvement	Prognosis
I	Epithelial defect, no haze	None	Good
II	Epithelial defect + haze, iris still visible	<1/3	Good
III	Total epithelial loss, haze, iris obscured	1/3–1/2	Guarded
IV	Opaque cornea, iris/pupil obscured	>1/2	Poor

Red flags: a high initial (alkali) pH, limbal ischaemia (vascular blanching — lost limbal stem cells impair corneal healing), and delayed presentation. Burns with facial or inhalation injury, and every paediatric chemical eye injury, need urgent ophthalmology or hospital discussion regardless of grade.

Safety-netting

Tell every patient to return urgently for worsening pain, new or worsening photophobia, discharge, or reduced vision — these suggest infection or ulceration rather than expected healing. Contact lens wearers should stay out of lenses until fully healed and reviewed.