What is the most appropriate next step in managing a patient with suspected penetrating eye injury after hammering metal, presenting with inflammation, impaired visual acuity, and an irregularly shaped pupil?

Management of Suspected Penetrating Eye Injury with Irregular Pupil

The patient requires CT scan of orbits and urgent ophthalmological review due to signs of globe penetration from a metallic foreign body.

Clinical Assessment and Reasoning

The patient presents with several concerning features that strongly suggest a penetrating eye injury:

• History of hammering metal with subsequent eye symptoms is highly suspicious for a metallic intraocular foreign body 1
• Reduced visual acuity in the affected eye (R: 6/12 vs L: 6/6) indicates ocular damage 2
• Irregular pupil shape is a critical sign of potential globe penetration or intraocular foreign body 3
• Mild inflammation suggests ocular trauma 2

These findings, particularly the irregular pupil, are highly concerning for a penetrating injury with a retained intraocular foreign body, even when no foreign body is visible on examination 3.

Immediate Management Plan

1. CT scan of orbits and urgent ophthalmological review is the most appropriate next step 2, 1

   • CT has 94.9% sensitivity for detection of intraorbital foreign bodies, especially metallic ones 1
   • Non-contrast thin-section orbital CT with multiplanar reconstructions is the recommended protocol 2, 1
   • MRI is contraindicated when metallic foreign bodies are suspected due to potential movement of the object caused by the magnetic field 1

2. Avoid eye manipulation until ophthalmological assessment 2

   • Do not attempt to evert the lids further as this could exacerbate any penetrating injury 2
   • Do not apply pressure to the eye 2

Rationale Against Other Management Options

• Topical antibiotics with eye pad and next-day review is inadequate for a suspected penetrating injury with an irregular pupil 2, 3

  • Delayed diagnosis of intraocular foreign bodies can lead to serious complications including endophthalmitis, retinal detachment, and siderosis 4
  • Self-sealing wounds may mask the severity of the injury 4

• Topical antibiotics with review only if symptoms persist is inappropriate given the high-risk presentation 2, 4

  • Waiting for symptoms to worsen could lead to permanent vision loss 4

• Referral to ophthalmologist within days to weeks is too delayed for a potential penetrating injury 2, 4

  • Immediate assessment is required to prevent vision-threatening complications 2, 4

Clinical Pearls and Pitfalls

• An irregular pupil after trauma is a red flag sign for penetrating eye injury, even when no foreign body is visible on examination 3
• Patients with occupational exposure to metal work are at high risk for occult intraocular foreign bodies 5
• Patients may present with good vision despite having a penetrating injury with a self-sealing wound 4
• Retained metallic foreign bodies can cause siderosis, leading to permanent vision loss if not promptly removed 4
• CT is superior to plain radiography for detecting and localizing metallic foreign bodies, fractures, soft tissue injuries, and assessing the extent of globe damage 2, 1