Related Subjects:
|Episcleritis
|Scleritis
|Assessing a Red eye
|Acute Angle Closure Glaucoma
|Allergic and Infective Conjunctivitis
|Anterior and Posterior Uveitis
|Herpes simplex keratitis (HSK)
|Acute Blepharitis
|Corneal Abrasion
|Foreign Body in Eye
Corneal and conjunctival foreign bodies (FBs) are common ophthalmic presentations, especially in metal workers, DIY enthusiasts, and children.
⚠️ They can cause pain, photophobia, and watering, and if neglected may lead to infection, scarring, and vision loss.
Early, careful removal and aftercare are essential.
🛠️ Instruments
- Gloves 🧤, sterile cotton bud, and a 21–25G needle (mainstay).
- Topical anaesthetic (e.g. Amethocaine 1%).
- Slit lamp 🔬 (essential for safe removal).
- Optional: motorised dental burr for metallic FBs (⚠️ never within central 5 mm of cornea).
- ⚙️ Technique: Bend needle tip to 45°; bevel away from eye to reduce trauma.
- Ensure patient’s forehead is firmly against the slit lamp for stability.
📋 Important Notes
- 📉 Visual acuity may initially be reduced - always test with pinhole + topical anaesthetic if discomfort limits accuracy.
- 🌱 Organic FBs (wood, plant matter) → high infection risk.
- 🧲 Metallic FBs → rust rings ⚠️ → scarring if untreated.
- Rust rings in the visual axis must be removed by ophthalmology only.
- Always consider the possibility of an open globe injury - if suspected → shield, nil by mouth, urgent ophthalmology referral.
🔧 Procedure
- 1️⃣ Instil topical anaesthetic (e.g., Amethocaine 1%), repeat every 30s until painless.
- 2️⃣ Seat patient at slit lamp; stabilise head; ask them to fixate on target 🎯.
- 3️⃣ Focus slit lamp beam - use narrow oblique beam at ~45° to assess FB depth.
- 4️⃣ Approach tangentially with cotton bud or bent needle; lift FB away.
- 5️⃣ For superficial metallic FB → gently “flick” with bevel; burr for rust ring (if outside visual axis).
🩺 Post-Procedure Care
- 💊 Topical antibiotic drops (e.g., chloramphenicol qid for 5–7 days).
- 🌙 Cycloplegic drops (e.g., cyclopentolate 1% bd) for pain relief.
- 💊 Oral analgesia (paracetamol, NSAIDs).
- ❌ Avoid eye padding - binocular vision prevents accidents and padding may ↑ infection risk.
- 🚫 No repeat use of anaesthetic drops → toxic to cornea.
- 📆 Follow-up daily with slit lamp until epithelial defect heals (document size + healing progress).
🚩 Red Flags
- ⚠️ Suspected penetrating eye injury (positive Seidel’s test, irregular pupil, iris prolapse).
- FB in central visual axis or deep stromal cornea.
- Persistent rust ring or residual opacity.
- Infective keratitis → pain ↑, photophobia, hypopyon.
- Reduced vision not improving after removal.
👶 Children
- Often difficult to examine; consider sedation or referral if uncooperative.
- Risk of recurrent rubbing and re-injury → protective shield + parental advice.
- Organic FBs (wood, playground material) more common.
🧓 Elderly
- Assess anticoagulation & bleeding risk 💊.
- May present late due to reduced corneal sensation or confusion.
- Healing may be slower; ensure close ophthalmology follow-up.
📌 Teaching Pearls
- Always document visual acuity before and after any intervention.
- Slit lamp exam is gold standard for safe removal.
- Never attempt deep or central FB removal outside specialist care.
- Discharge advice: return immediately if ↑ pain, redness, discharge, or ↓ vision.
🧾 Clinical Case Examples – Foreign Body in the Eye
A 34-year-old construction worker presents with sudden onset pain, watering, and photophobia in the right eye after drilling metal. On exam, visual acuity is intact, and a small metallic speck is seen on the cornea.
👉 Likely diagnosis: Superficial corneal foreign body (metallic).
👉 Management: Topical anaesthetic, fluorescein staining, removal with cotton bud/needle, tetanus check, topical antibiotic drops.
Case 2 – Organic Material 🌾
A 19-year-old farmer reports foreign body sensation and tearing after cutting hay. On slit-lamp exam, a small plant fragment is lodged under the upper eyelid.
👉 Concern: Vegetative matter foreign body (↑ risk fungal keratitis).
👉 Management: Lid eversion and removal, topical antibiotic cover, warn about red flags (increasing pain, vision change), urgent ophthalmology review if keratitis suspected.
Case 3 – Contact Lens Wearer 👁️
A 26-year-old woman wearing contact lenses complains of painful red eye and foreign body sensation after a night out. No visible foreign body but corneal staining with fluorescein shows an epithelial defect.
👉 Likely diagnosis: Contact lens–related corneal abrasion ± retained foreign body.
👉 Management: Urgent removal of lens, ciprofloxacin drops (anti-pseudomonal), ophthalmology referral if worsening.
Case 4 – Penetrating Injury 🚨
A 40-year-old man using a hammer develops sudden severe eye pain and blurred vision. He cannot open his eye. Exam: subconjunctival haemorrhage, peaked pupil, and reduced visual acuity.
👉 Concern: Penetrating globe injury with intraocular foreign body.
👉 Management: Do NOT manipulate. Rigid eye shield, nil by mouth, urgent ophthalmology referral for surgical exploration.
Case 5 – Child with Grit 🧒
A 6-year-old boy is brought by his mother after playing in a sandpit. He is rubbing his left eye, which is red and watering. VA normal for age, small particle found under lower lid.
👉 Likely diagnosis: Superficial eyelid foreign body.
👉 Management: Lid eversion, irrigation with saline, discharge with advice on when to return (worsening pain, blurred vision).