A 35-year-old construction worker presents 4 hours after a penetrating injury to the right eye from a metallic fragment. Visual acuity is hand motions. On slit-lamp examination, there is a 3 mm corneal laceration with iris prolapse, and the anterior chamber is shallow with fibrin. The pupil is mid-dilated and non-reactive. Intraocular pressure is 8 mmHg. What is the most critical immediate action before any other intervention?

Explanation

## Management of Penetrating Ocular Injury with Globe Integrity Compromise ### Recognition of Globe Rupture **Key Point:** The clinical triad of low IOP (8 mmHg), shallow anterior chamber, and iris prolapse indicates loss of globe integrity. This is a surgical emergency requiring immediate protection and repair. ### Why Protective Shield and Urgent Repair Are Priorities **High-Yield:** In penetrating ocular trauma with confirmed or suspected globe rupture: 1. **Do NOT perform further diagnostic testing** (Seidel test, CT, gonioscopy, dilated fundoscopy) — these manipulate the globe and risk extrusion of intraocular contents. 2. **Apply a rigid protective shield immediately** to prevent further trauma and leakage. 3. **Arrange urgent surgical repair** (within 24 hours ideally, but sooner if possible) to restore globe integrity and salvage vision. ### Clinical Evidence of Rupture | Finding | Significance | |---------|-------------| | Corneal laceration (3 mm) | Direct breach of globe wall | | Iris prolapse | Prolapsed iris indicates full-thickness corneal defect | | Shallow anterior chamber | Loss of aqueous due to leakage | | Low IOP (8 mmHg) | Aqueous escape; normal IOP is 10–21 mmHg | | Mid-dilated, non-reactive pupil | Iris sphincter damage or anterior segment ischemia | | Fibrin in AC | Inflammatory response to tissue disruption | **Clinical Pearl:** A single finding (e.g., low IOP) may be ambiguous, but the constellation of corneal laceration + iris prolapse + shallow AC + low IOP is pathognomonic for globe rupture. ### Contraindicated Actions ```mermaid flowchart TD A[Penetrating injury with iris prolapse + low IOP]:::outcome --> B{Globe integrity intact?}:::decision B -->|No/Unclear| C[STOP all diagnostic manipulation]:::urgent C --> D[Apply protective rigid shield]:::action D --> E[Arrange urgent surgical repair]:::action E --> F[Imaging only if intraocular FB suspected and repair delayed]:::action B -->|Yes confirmed| G[Seidel test, CT, detailed exam OK]:::action ``` **Warning:** Seidel test (fluorescein dye to visualize aqueous leakage) and CT imaging are appropriate ONLY if globe rupture is not clinically evident. In this case, the diagnosis is already made; further testing delays definitive treatment. ### Surgical Repair Principles - Primary repair of corneal laceration under operating microscope - Restoration of anterior chamber - Iris repositioning or repair as needed - Tetanus prophylaxis and broad-spectrum antibiotics (systemic) - Cycloplegia and topical steroids post-operatively **High-Yield:** The prognosis of penetrating ocular injury depends on **timing of repair**. Delays increase risk of infection, posterior synechiae, and permanent vision loss. [cite:Khurana Textbook of Ophthalmology Ch 16; Yanoff & Duker Ophthalmology 5e Ch 6.2]