A 25-year-old factory worker splashes alkali (10% NaOH) into his right eye. On presentation 20 minutes later, the cornea shows diffuse haze with loss of clarity, the limbal vessels are completely blanched (ischaemia 360°), and the conjunctiva is white. According to Roper-Hall/Ballen grading, this injury is:
- A Grade I (very mild)
- B Grade IV (very severe) ✓
- C Grade II (mild to moderate)
- D Grade III (severe)
Correct answer: B. Grade IV (very severe)
Explanation
Roper-Hall grading of ocular chemical burns: Grade IV (very severe) — cornea totally opaque (no iris details visible), limbal ischaemia > 50% (classically >1/2 circumference, here 360°). This carries the worst prognosis. Grade III has partial corneal haze with 30–50% limbal ischaemia. Prognosis correlates with limbal ischaemia: the limbal stem cells are destroyed, impairing corneal re-epithelialisation. Immediate copious irrigation is the first priority regardless of grade.
Reference: Khurana Comprehensive Ophthalmology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.