Certified Ophthalmic Medical Technologist (COMT) Practice Exam

What is the amount of hyperopia for a 10-year-old male with normal ocular structures and 39 D of spherical corneal power?

1. +2 D of curvature hyperopia

2. +3 D of curvature hyperopia

3. +4 D of curvature hyperopia

4. +5 D of curvature hyperopia

The correct answer is: +4 D of curvature hyperopia

To determine the amount of hyperopia for a 10-year-old male with normal ocular structures and a corneal power of 39 D, we need to understand the relationship between the power of the cornea and hyperopia. In this case, the significant factor is the typically expected emmetropic (normal) corneal power, which is around 43 D. Hyperopia, or farsightedness, occurs when the eye's optical power is less than the refractive requirement of the eye, causing light to focus behind the retina. To calculate the curvature hyperopia, we can use the difference between the average expected corneal power and the actual corneal power. If we expect a normal corneal power of 43 D and the given power is 39 D, the difference is 4 D. This implies that there is a curvature hyperopia of +4 D, indicating that the eye has less refractive power than expected for this age group with normal ocular development. Thus, the answer of +4 D of curvature hyperopia accurately reflects the condition where the amount of hyperopia is derived from the shortfall in corneal power compared to expected standards for age and normal ocular structure.