Ocular foreign body

Background

• Ocular foreign bodies are a high-risk chief complaint because of short and long-term threats to vision loss. The main goal is to determine superficial vs. intraocular foreign bodies.
• Always consider possibility of multiple foreign bodies

Clinical Features

A small piece of iron lodged near corneal margin.

• Patient history with focus on circumstances/mechanism of symptom onset
  • e.g. use of power tools, projectile weapons, MVCs, metal-on-metal impacts, or high-impact trauma
  • Most common is metal foreign body from hammering

Superficial (embedded in conjunctiva or cornea)

• Eye pain
• Foreign body sensation
• Tearing
• Blurry Vision
• Relief of pain with topical anesthesia

Intraocular

• As above, although may additionally be asymptomatic initially and present after complications arise (e.g. corneal ulcer)
• +Sidel's sign: streaming of fluorescein out of eye

Differential Diagnosis

Orbital trauma

Acute

• Ruptured Globe^
• Corneal Abrasion
• Ocular foreign body
• Conjunctival laceration
• Caustic Keratoconjunctivitis^^
• Subconjunctival hemorrhage
• Traumatic iritis
• Traumatic hyphema
• Retinal detachment
• Retrobulbar hemorrhage/hematoma
• Traumatic mydriasis
• Orbital fracture
  • Frontal sinus fracture
  • Naso-ethmoid fracture
  • Inferior orbial wall fracture
  • Medial orbital wall fracture

Subacute/Delayed

• Endophthalmitis^
• Corneal Ulcer^

Unilateral Red Eye

• Acute angle-closure glaucoma^
• Anterior uveitis
• Caustic keratoconjunctivitis^^
• Conjunctival laceration
• Conjunctivitis
• Corneal abrasion
• Corneal erosion
• Ocular foreign body
• Corneal ulcer^
• Endophthalmitis^
• Episcleritis
• Globe rupture^
• Herpes zoster ophthalmicus
• Intraocular foreign body
• Inflamed pingueculum
• Inflamed Pterygium
• Keratoconjunctivitis
• Keratoconus
• Lens dislocation
• Nontraumatic iritis
• Scleritis^
• Subconjunctival hemorrhage
• Traumatic hyphema
• Traumatic iritis
• Ultraviolet keratitis

^Emergent diagnoses

^^Critical diagnoses

Evaluation

Based on patient mechanism/history

• Possible high impact metal (e.g. hammering, use power tools, projectile weapons, metal-on-metal impacts, or high-impact trauma)
  • Eye exam
    • Slit lamp exam with fluorescein
    • Intraocular pressure
    • Extensive ocular exam with lid eversion or sweep to check for subtarsal foreign bodies
  • CT orbit
• Non-high impact metal history (vegetation, dirt, dust)
  • Eye exam only
    • Slit lamp exam with fluorescein
    • Intraocular pressure
    • Extensive ocular exam with lid eversion or sweep to check for subtarsal foreign bodies

Contraindicated

• Ocular ultrasound in setting of open globe injury
• Plain films only detect 40% of IOFB (intra-ocular foreign bodies), so generally not obtained

Management

• Tetanus booster as needed
• Pain control with topical NSAIDs (e.g. diclofenac or ketorolac) or oral opioids

Superficial ocular foreign body with no signs of open globe injury

• Conjunctival foreign body
  • ED removal after topical anesthetic
    • Copious irrigation
    • Cotton-tipped swab soaked in saline
• Rust ring
  • Not a true emergency as many will wash out spontaneously
  • May be removed with a 30- to 25-gauge needle as below
• Corneal foreign body
  • ED removal after topical anesthetic
  • May attempt irrigation and/or cotton-swab as above
  • 30- to 25-gauge needle under slit lamp
    • Approach from tangential angle
  • Repeat Seidel test to ensure removal did not perforate cornea
  • Irrigate eye profusely post-removal
  • Consider cycloplegics (e.g. cyclopentolate or homatropine) for significant photophobia
  • Consider topical antibiotics for corneal involvement
    • Target gram-positive + pseudomonas (contact wearers)
    • Moxifloxacin – best ophthalmologic penetration

Does Not Wear Contact Lens

• Erythromycin ointment qid x 3-5d OR
• Ciprofloxacin 0.3% ophthalmic solution 2 drops q6 hours
• Ofloxacin 0.3% solution 2 drops q6 hours
• Sulfacetamide 10% ophthalmic ointment q6 hours

Wears Contact Lens

Antibiotics should cover pseudomonas and favor 3rd or 4th generation fluoroquinolones

• Levofloxacin 0.5% solution 2 drops ever 2 hours for 2 days THEN q6hrs for 5 days OR
• Moxifloxacin 0.5% solution 2 drops every 2 hours for 2 days THEN q6hrs for 5 days OR
• Tobramycin 0.3% solution 2 drops q6hrs for 5 days OR
• Gatifloxacin 0.5% solution 2 drops every 2 hours for 2 days THEN q6hrs for 5 days OR
• Gentamicin 0.3% solution 2 drops six times for 5 days

Intraocular foreign bodies or concern for open globe injury

• Emergent ophthalmology consult
• Prophylactic empiric antibiotics
• Placement of rigid eye shield
• Analgesia (oral NSAIDS or opioids) and antiemetics as necessary

Disposition

Outpatient Ophthalmology Follow-up

• Superficial ocular foreign body after removal
  • Ophtho follow up in 48h for routine cases
  • Ophtho follow up in 24h for rust ring removal

Admission

• With emergent surgical intervention for:
  • Intraocular foreign body
  • Evidence of open globe

See Also

• Corneal abrasion
• Eye Algorithms (Main)
• Corneal ulcer
• Conjunctival abrasion
• Foreign bodies

References

Authors

David Xu, Ross Donaldson, Daniel Ostermayer, Neil Young