Corneal Abrasion
The most likely diagnosis is B. Corneal abrasion 1, 2, 3. The clinical presentation of acute traumatic injury from a wooden foreign body, severe eye pain, photophobia, inability to open the eye, and fluorescein-positive epithelial defect is pathognomonic for traumatic corneal abrasion.
Clinical Reasoning
The key diagnostic features that distinguish this as corneal abrasion include:
- Acute traumatic mechanism: Wooden foreign body directly causing mechanical epithelial injury 3, 4
- Classic symptom triad: Severe pain, photophobia, and foreign body sensation are hallmark features of corneal abrasion 3, 5
- Fluorescein-positive epithelial defect: This confirms disruption of the corneal epithelium, which is the defining feature of abrasion 1, 5
- Immediate symptom onset: Corneal abrasions present acutely following trauma, unlike ulcers which develop over time 3, 6
Why Not the Other Options
Corneal ulcer (Option A) would present with suppurative stromal infiltrates greater than 1 mm with indistinct edges, stromal edema, and white cell infiltration in surrounding stroma—not just a simple epithelial defect 7. Ulcers typically develop over days with progressive worsening, not immediately after trauma 7.
Subconjunctival hemorrhage (Option C) presents as painless blood-red appearance beneath the conjunctiva without epithelial defects, photophobia, or inability to open the eye 2.
Acute conjunctivitis (Option D) causes discharge, conjunctival injection, and mild discomfort, but not severe pain, marked photophobia, or fluorescein-positive epithelial defects 7.
Critical Management Considerations
Immediate Treatment
- Topical antibiotics for prophylaxis: Use Polytrim (polymyxin B-trimethoprim) drops during the day or erythromycin ointment at bedtime for broad-spectrum coverage 1
- Pain control: Oral acetaminophen or NSAIDs are recommended; topical NSAIDs may also be used 1, 3, 5
- No eye patching: Multiple studies demonstrate patching does not improve pain and may delay healing 1, 3, 5
Important Caveats for Wooden Foreign Bodies
Organic material like wood carries higher infection risk 4. While standard broad-spectrum prophylaxis is typically sufficient for non-contact lens abrasions 1, wooden foreign bodies warrant:
- Careful examination to ensure complete foreign body removal 2, 5
- Close follow-up within 24 hours to monitor for signs of infection 1, 8
- Patient education about red flags: increasing pain, purulent discharge, or worsening vision 1
Red Flags Requiring Immediate Ophthalmology Referral
- High-velocity mechanism suggesting possible globe penetration 7, 2
- Irregular pupil, eye bleeding, or vision loss after trauma 7, 2
- Corneal infiltrate or ulcer development 1, 5
- Symptoms not improving or worsening within 24-48 hours 8, 5
Common Pitfalls to Avoid
Do not use topical corticosteroids before ruling out infection, as steroids can worsen infectious keratitis 9. Most simple corneal abrasions heal within 24-72 hours with conservative management 3, 6.