Certified Ophthalmic Assistant Practice Exam

Which process is useful for measuring corneal astigmatism?

1. Optometry

2. Keratometry

3. Perimetry

4. Retinoscopy

The correct answer is: Keratometry

Keratometry is specifically designed for measuring the curvature of the cornea, which is crucial for diagnosing and managing corneal astigmatism. Astigmatism occurs when the cornea has an irregular shape, causing light to focus unevenly on the retina. Keratometers utilize a principle of reflected light to determine the steepness and flatness of the cornea, providing precise measurements needed to understand the extent and direction of astigmatism. In contrast, while optometry encompasses a range of vision-related services, it isn’t a specific measurement process. Perimetry, which assesses the visual field, and retinoscopy, used for determining refractive errors, also do not focus on the corneal shape or curvature. Therefore, keratometry stands out as the appropriate method to evaluate corneal astigmatism effectively.