Classification of Ocular Trauma

Trauma Triage - Setting the Scene

Ocular trauma refers to injury to the eye or its adnexa. Standardized classification is crucial for effective communication, guiding management, and predicting prognosis. The Birmingham Eye Trauma Terminology (BETT) is the globally accepted system.

• Closed Globe Injury (CGI): Eyewall (sclera, cornea) is intact; no full-thickness wound.
  • Contusion: Caused by blunt trauma. Eyewall is not breached.
    • Examples: Hyphema (blood in anterior chamber), iridodialysis (iris root tear), commotio retinae (retinal "bruising").
  • Lamellar Laceration: Partial-thickness wound of the eyewall.
    • Example: Corneal abrasion.

⭐ Vossius ring, an imprint of iris pigment on the anterior lens capsule, is a pathognomonic sign of previous significant blunt ocular trauma.

Globe Breaches - When Walls Fall

• Open Globe Injury (OGI): A full-thickness wound of the eyewall (cornea or sclera).
• Types based on Mechanism:
  • Rupture: Caused by blunt trauma; an "inside-out" injury. The globe bursts at its weakest point due to a sudden rise in intraocular pressure.
  • Laceration: Caused by a sharp object; an "outside-in" injury.
    • Penetrating Injury: Single entry wound, no exit wound. The object may be retained.
    • Perforating Injury: Two wounds: an entry and an exit wound caused by the same object.
    • Intraocular Foreign Body (IOFB): A foreign object is retained within the eye (a type of penetrating injury). 📌 Mnemonic for Lacerations: Poor Patient Injured (Penetrating, Perforating, IOFB).
• Key Diagnostic Sign: Positive Seidel's test (streaming of fluorescein-stained aqueous humor from the wound site).

![Diagram illustrating types of open globe injuries: rupture, penetrating, perforating, and IOFB]

⭐ A positive Seidel's test (fluorescein streaming from a wound) is diagnostic of a full-thickness corneoscleral laceration and an open globe.

BETT Unpacked - Code of Conduct

The Birmingham Eye Trauma Terminology (BETT) standardizes ocular trauma classification.

• Type:

  • A: Closed globe injury (contusion/lamellar laceration)
  • B: Open globe injury (rupture/laceration - full thickness)

• Grade (Visual Acuity):

  Grade	Visual Acuity (VA)
  1	≥ 20/40
  2	20/50 - 20/100
  3	19/100 - 5/200
  4	4/200 - Light Perception (LP)
  5	No Light Perception (NLP)

• Pupil:

  • P: Positive RAPD (Relative Afferent Pupillary Defect)
  • N: Negative RAPD

• Zone (Open Globe Injury):

  • Zone I: Cornea, limbus.
  • Zone II: Limbus to 5mm posterior into sclera.
  • Zone III: Posterior to Zone II (>5mm from limbus).

⭐ In BETT, Zone III injuries (posterior to 5mm from limbus) carry the poorest visual prognosis among open globe injuries.

OTS Outlook - Future Gazing

OTS prognosticates visual outcomes by assigning points to key variables at presentation.

⭐ The Ocular Trauma Score (OTS) is a validated system that sums points from six key clinical variables at presentation to predict the likelihood of various visual outcomes six months after significant ocular injury.

OTS Variables and Raw Points:

High‑Yield Points - ⚡ Biggest Takeaways

• BETT is the universal standard for ocular trauma classification.
• Differentiate Open Globe Injury (OGI) from Closed Globe Injury (CGI).
• OGI: Rupture (blunt, inside-out) or Laceration (sharp, outside-in).
• Lacerations: Penetrating (entry), Perforating (entry & exit), IOFB.
• CGI: Contusion (no full-thickness defect) or Lamellar Laceration (partial thickness).
• Zone of injury (I, II, III) is vital for OGI prognosis.
• Classify by type: mechanical vs. non-mechanical (chemical, thermal).