Certified Paraoptometric (CPO) Practice Exam 2025

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Gear up for the Certified Paraoptometric (CPO) Exam 2025. Study with interactive quizzes and multiple-choice questions with comprehensive explanations. Excel in your exam with our tailored preparation tools!

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What is the primary role of additional curves in the back surface of contact lenses?

  1. To improve visual clarity

  2. To assist in fitting the lens

  3. To provide UV filtering

  4. To enhance aesthetic appeal

The correct answer is: To assist in fitting the lens

The primary role of additional curves in the back surface of contact lenses is indeed to assist in fitting the lens. The curvature of the back surface of a contact lens must match the curvature of the surface of the cornea to ensure proper alignment and comfort. A well-fitted lens will remain stable on the eye, allowing for optimal movement with the blinking of the eyelid, which is essential for tear exchange and lens hydration. This fitting process helps to minimize discomfort, vision distortion, and the risk of complications such as corneal abrasion. While improving visual clarity, providing UV filtering, and enhancing aesthetic appeal are important aspects of contact lenses, they are secondary to the essential function of fitting that the additional curves facilitate. Proper fitting is critical because a lens that does not fit well can lead to various issues, whereas aesthetics and visual clarity become significant only after the basic fit is achieved.