A 35-year-old patient is found to have elevated IOP of 26 mmHg bilaterally, open angles, normal visual fields, and a cup-to-disc ratio of 0.6. The clinician wishes to calculate the absolute risk of conversion to glaucoma over 5 years. According to the Ocular Hypertension Treatment Study (OHTS), which TWO factors carry the highest predictive weight in the OHTS risk calculator?
- A Age and pattern standard deviation on visual fields
- B Central corneal thickness and vertical cup-to-disc ratio ✓
- C IOP level and family history of glaucoma
- D Disc hemorrhage presence and Humphrey mean deviation
Correct answer: B. Central corneal thickness and vertical cup-to-disc ratio
Explanation
The OHTS risk calculator assigns the greatest predictive weight to central corneal thickness (thinner corneas = higher risk) and vertical cup-to-disc ratio (larger ratio = higher risk). IOP level contributes but less strongly. The OHTS demonstrated that a thin CCT (<555 µm) is a significant independent risk factor for conversion from ocular hypertension to POAG, independent of its effect on applanation tonometry accuracy.
Reference: Khurana Comprehensive Ophthalmology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.