What is the most appropriate next step for a middle-aged man with severe eye pain after a metal foreign body became lodged in his cornea (corneal foreign body)?

Management of Corneal Metallic Foreign Body

For a middle-aged man with a metal foreign body lodged in the cornea causing severe pain, the most appropriate next step is to refer to ophthalmology (Answer A), particularly if the foreign body is embedded, difficult to remove, or if you lack appropriate equipment for safe removal. 1

Immediate Assessment Priorities

Before any intervention, you must rule out vision-threatening conditions:

• Test visual acuity immediately to establish baseline function and identify any acute vision loss that would mandate urgent ophthalmology referral 2
• Assess for penetrating injury or intraocular foreign body, which requires immediate ophthalmology consultation 1
• Look for high-velocity mechanism (grinding, hammering, metal cutting) - these injuries have higher risk of globe penetration and demand urgent specialist evaluation 3, 1, 4
• Check pupil shape and reactivity - an irregular pupil after trauma indicates penetrating injury requiring immediate referral 3

Decision Algorithm for Management

Immediate Ophthalmology Referral Required If:

• High-velocity mechanism of injury (grinding, nailing, metal work) 3, 1
• Suspicion of penetrating injury or intraocular foreign body 1
• Irregular pupil, eye bleeding, or vision loss 3
• Foreign body is deeply embedded or cannot be safely removed 1
• Lack of appropriate equipment (slit lamp, magnification) for safe removal 5

May Attempt Removal at Primary Care Level If:

• Low-velocity superficial foreign body 3
• Adequate equipment available (slit lamp or magnification) 5
• Provider has appropriate training and experience 6
• No signs of penetrating injury 1

If Attempting Removal (When Appropriate)

The removal process should include:

• Irrigate the eye first with sterile saline to flush loose material 1
• Remove visible foreign body atraumatically using appropriate magnification 6
• Address rust ring - metal foreign bodies commonly leave rust deposits that must be eliminated 6
• Apply broad-spectrum topical antibiotic prophylaxis (e.g., moxifloxacin four times daily) after removal 1

Post-Removal Management

Pain control should be multimodal:

• Topical NSAID (ketorolac) for pain, photophobia, and foreign body sensation 1
• Oral acetaminophen or NSAIDs for additional relief 3, 1
• Cycloplegic agents (cyclopentolate) to reduce ciliary spasm pain 1

Critical Pitfalls to Avoid

Never prescribe topical corticosteroids - these promote corneal ulceration and melting, particularly with fungal contaminants or delayed treatment, and can lead to corneal perforation 7, 6

Do not prescribe topical anesthetics for home use - they mask pain from retained foreign bodies or developing corneal ulcers 6

Avoid eye patching - current evidence does not support patching for corneal abrasions 1

Do not allow patient self-treatment - 52% of metallic foreign body patients attempt self-removal, which increases complications 4

Special Considerations for Metal Foreign Bodies

Metal foreign bodies carry unique risks:

• Rust ring formation occurs in 26% of cases and requires complete removal to prevent ongoing inflammation 4
• 58% of workers with metallic corneal foreign bodies have corneal scars from previous injuries, indicating high recurrence risk 4
• Metal industry workers have 59% of these injuries, typically from metal cutting (65% of cases) 4

Follow-Up Requirements

All patients require close follow-up within 24-48 hours to assess for:

• Corneal infection development 1
• Incomplete foreign body or rust ring removal 6
• Corneal ulceration 6
• Persistent symptoms requiring specialist evaluation 3

Given the severe pain, embedded nature ("lodged in cornea"), and metal composition in this case, ophthalmology referral is the safest approach unless you have immediate access to appropriate equipment and expertise for safe removal. 1, 5