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OP10.6 | Ocular Injuries: Classification, Primary Management and Referral — SDL Guide (Part 3)

Diagnosis, Assessment of Severity, and Investigations

After initial first aid (irrigation for chemical burns; Fox shield for open globe), a systematic assessment establishes injury severity and guides specialist management.

Fluorescein staining: A cornerstone investigation for corneal injury. Apply fluorescein eye drops (or a fluorescein-impregnated strip) and illuminate with a cobalt-blue filter (slit lamp, or blue light on a direct ophthalmoscope). Corneal epithelial defects stain bright green. In a chemical burn, fluorescein staining maps the extent of epithelial damage. In a penetrating wound, the Seidel test using fluorescein reveals aqueous leakage.

B-scan ultrasound: When media is opaque (dense hyphaema, vitreous haemorrhage, severe corneal oedema), B-scan provides information about posterior segment integrity — vitreous haemorrhage, retinal detachment, IOFB, choroidal detachment.

X-ray of orbit (AP + lateral): For suspected metallic IOFB. Detects metallic foreign bodies. NEVER perform MRI if a metallic IOFB is suspected — the magnetic field will displace the ferromagnetic fragment within the eye, causing catastrophic intraocular injury.

CT orbit: Better than X-ray for localising IFOBs (including non-metallic ones), assessing bony fractures (blow-out fracture), and evaluating extent of penetrating injury.

Intraocular pressure (IOP): Must NOT be measured by applanation tonometry in a suspected open globe (contact with the globe can extrude contents). IOP is relevant in blunt trauma (elevated IOP with hyphaema or lens dislocation) — use a non-contact tonometer cautiously, or estimate clinically by digital palpation (soft = hypotony; hard = elevated IOP).

Roper-Hall grading (for chemical burns, as described above) guides prognosis and management intensity — Grades III and IV require tertiary referral for potential limbal stem cell transplantation and corneal grafting.

Management Principles and Indications for Referral

First-contact management for each injury type, followed by appropriate referral. The management principles for ocular trauma are designed around a single overarching goal: do no further harm while stabilising the patient and arranging definitive specialist care. For the first-contact doctor — whether a casualty officer, a PHC medical officer, or an emergency nurse — the most important actions are often the ones not taken: not applying pressure to an open globe, not removing an impaled object, not instilling drops into a perforated eye, not ordering MRI when a metallic intraocular foreign body is suspected. These negative rules are as important as the positive actions (irrigate chemical burns, apply Fox shield, give IV antibiotics, keep nil by mouth) because a single wrong action at the first-contact stage can turn a potentially salvageable eye into a lost one. The referral thresholds described below are graded by urgency — from the same-hour emergency referral for open globe injuries and chemical burns with corneal involvement, through the 24-hour urgent referral for significant hyphaema, to the routine referral for orbital fractures with diplopia. Knowing these thresholds — and being able to justify them — is the core MBBS-level competency for ocular trauma management.

Chemical burns:
1. Copious irrigation immediately (saline/water; minimum 30 min for alkali; until pH 7.0–7.4).
2. Remove lime particles from fornices (sweep with moistened cotton bud during irrigation).
3. Topical anaesthetic (tetracaine/proxymetacaine) to allow examination and cooperation — after starting irrigation.
4. Topical antibiotics (chloramphenicol) + lubricants (artificial tears).
5. Topical steroids (dexamethasone) for the first 7–10 days to reduce inflammation (use with caution — can mask infection).
6. Ascorbate eye drops (Vitamin C, 10%) to support corneal collagen synthesis.
7. Refer urgently to ophthalmology — Grades III and IV especially need limbal stem cell assessment.

Closed globe (blunt) injuries:
1. Hyphaema: bed rest 30–45° head up, avoid aspirin/NSAIDs, topical steroid, anti-emetics (prevent Valsalva); refer ophthalmology within 24 hours for IOP monitoring and monitoring for secondary haemorrhage.
2. Commotio retinae: arrange dilated fundus examination by ophthalmologist; CNVM surveillance.
3. Orbital blow-out fracture: CT orbit; surgical repair if diplopia or enophthalmos significant (typically within 2 weeks).
4. Lens dislocation: refer ophthalmology; anterior chamber dislocation is emergency (acute angle-closure glaucoma).

Open globe injuries:
1. Apply Fox shield (rigid shield resting on orbital rim — NO pressure on globe).
2. Nil by mouth.
3. IV antibiotics (ciprofloxacin 400 mg IV + vancomycin 1 g IV, or per local protocol).
4. Tetanus toxoid/immunoglobulin (wound is contaminated).
5. Anti-emetic (prevent Valsalva during vomiting).
6. Urgent referral to tertiary vitreoretinal surgeon for surgical repair of the globe (primary closure) within 24 hours ideally, or as soon as possible.
7. Never delay referral for imaging (do X-ray en route, or at the referral centre).

Indications for referral — ALL ocular trauma:
- Any open globe: EMERGENCY referral, same hour.
- Any chemical burn with corneal involvement or limbal ischaemia: URGENT referral, same day.
- Hyphaema with grade ≥II or rising IOP: URGENT, within 24 hours.
- Suspected IOFB: URGENT, within hours (risk of endophthalmitis + siderosis).
- Traumatic cataract, lens dislocation: URGENT.
- Vitreous haemorrhage or suspected retinal detachment: URGENT.
- Orbital blow-out fracture with diplopia: routine referral within 1–2 weeks.

Self-Assessment: Ocular Trauma Decision Checklist

Before your casualty or ophthalmology posting, verify that you can apply the following decision rules immediately and correctly under exam or clinical conditions. Ocular trauma is one of the highest-stakes topics in emergency ophthalmology — errors in first-contact management (applying pressure to an open globe, ordering MRI for a suspected metallic IOFB, delaying irrigation of a chemical burn) cause immediate, preventable, and often irreversible harm. For the MBBS examination, this SDL is tested both as short-answer questions (enumerate the 'do-nots' in open globe management; describe the first action in chemical burns) and as clinical vignettes where the student must identify the injury type, state the first-contact management steps in sequence, and specify the urgency and destination of referral. The five decision rules below are the minimum safe-practice requirements for any doctor working in a casualty or district hospital setting.

Decision rule 1 — Chemical burn first action: Immediate copious irrigation with available water or saline — before examination, before calling ophthalmology, before recording visual acuity. Irrigate until conjunctival pH is 7.0–7.4.

Decision rule 2 — Open globe management: Apply Fox shield (rigid, resting on orbital rim — no pressure on eye). No pressure pad. No eye drops. No tonometry. No removal of impaled objects. Nil by mouth. IV antibiotics. Tetanus. Urgent transfer.

Decision rule 3 — IOFB imaging: X-ray orbit (AP + lateral) or CT orbit. NEVER MRI when a metallic IOFB is suspected — the magnetic field displaces the fragment and causes catastrophic intraocular injury.

Decision rule 4 — Hyphaema management: Bed rest at 30–45°, avoid aspirin and NSAIDs, warn about secondary haemorrhage on days 2–5. Grade ≥II or rising IOP = ophthalmology within 24 hours.

Decision rule 5 — Alkali vs acid burns: Alkali (lime, cement, ammonia) is worse than acid — liquefactive necrosis with no protein barrier, continuous penetration. Acid forms a coagulative barrier limiting depth. Irrigation is equally urgent for both, but alkali requires longer irrigation and pH monitoring.