Certified Ophthalmic Assistant Practice Exam

Which refractive error typically requires corrective lenses with positive power?

1. Myopia

2. Hyperopia

3. Astigmatism

4. Presbyopia

The correct answer is: Hyperopia

The choice of hyperopia as the correct answer is based on the nature of this refractive error, which is characterized by difficulty seeing nearby objects clearly due to the eye being shorter than normal or the cornea having too little curvature. This leads to light rays focusing behind the retina when looking at close objects. To correct hyperopia, positive-powered lenses are used, which help to converge light rays before they enter the eye, effectively moving the focus forward onto the retina. Myopia, on the other hand, is when the eye is too long or has too much curvature, causing distant objects to appear blurry. This refractive error requires corrective lenses with negative power. Astigmatism results from an irregular shape of the cornea or lens, distorting vision at all distances and requiring cylindrical lenses for correction but does not necessarily imply positive or negative power without further specification. Presbyopia is an age-related condition affecting near vision and often necessitates reading glasses with positive power, but hyperopia is specifically characterized by a need for positive correction in the absence of age-related factors.