inIntraocular foreign body (IOFB)

Question 1

what are the signs in the eyewall?

Answer 1

Corneoscleral wound

Fluorescein stain (for epithelial defect, which can persist even if FB is no longer present)

Question 2

what are the signs in the iris?

Answer 2

• ***Peaked pupil: because of iris prolapse through the sclera (the peak points towards the point of greatest weakness/ prolapse) 🡪 suspicious for globe rupture!
• Iris defects, e.g. punched out lesions
• Devitalised iris: macerated, feathery, depigmented, loss of tone
• Shallower anterior chamber depth 🡪 suspicious for leakage of aqueous humour, anterior prolapse, open globe injury

Question 3

what are the signs in the lens?

Answer 3

Focal opacity: if stellate/rosette (flower petal) shaped, may indicate traumatic cataract

Penetration/rupture of lens capsule

Phacodonesis (vibration of lens with movement), 2’ to lens subluxation

Question 4

what are the signs in the anterior chamber?

Answer 4

Vitreous strands can be seen in AC

Check for penetration/rupture of lens capsule

Check for phacodonesis or lens subluxation

Question 5

what are the signs in the sclera?

Answer 5

Carefully examine, especially if corneal laceration extends to/past limbus

Look carefully for exposed uveal tissue under conjunctiva

Question 6

what are the investigations?

Answer 6

• CT orbit: More reliable than XR for reporting size, shape, location of FB
• XR orbit: Useful for detecting IOFB, but does not localise radiopaque FB
• MRI orbit is strictly contraindicated, due to risk of a metallic/ferrous FB (even if patient denies metallic FB)
• U/S is contraindicated, because it applies pressure on the globe

Question 7

what is the management?

Answer 7

Initial management (in primary care setting, before CT orbit)

• Eye shield + no touching, no pressure (pressure will increase protrusion of ocular contents)
• IV/IM abx (no PO), usually IV ciprofloxacin (good penetration into the eye)
• Anti-tetanus toxoid (ATT), in view of metallic FB
• Keep NBM for emergency surgery (EOT)
• STAT admission to ED

Definitive management

• Surgery (STAT), within 24 hours
• In OT under general anaesthesia (GA): surgical removal of FB, vitrectomy + debride non-viable tissue + replace prolapsed viable tissue + restore globe integrity (close any entry wounds)
• Delaying surgery increases the risk of post-traumatic endophthalmitis (exogenous endophthalmitis)

Prophylactic antibiotics to reduce risk of infection (endophthalmitis)

• Intra-op anterior chamber (intracameral) + intravitreal + post-op topical and oral abx
• Monitor closely for signs of ocular infection