Certified Paraoptometric (CPO) Practice Exam 2025

Which condition is characterized by a loss of vision in one or both eyes?

1. Amblyopia

2. Aphakia

3. Glaucoma

4. Esotropia

The correct answer is: Amblyopia

Amblyopia is a condition commonly known as "lazy eye" and is characterized by a decrease in vision in one eye, or in some cases, both. This condition usually develops in childhood and occurs when the brain does not properly recognize or interpret visual signals from one eye, often due to various developmental factors. It is important to understand that amblyopia represents a functional vision loss rather than a structural issue with the eye itself, which means that the affected eye may appear normal but is not being used effectively by the brain. The other options provided relate to different ocular conditions: Aphakia involves the absence of the eye's lens, often leading to refractive errors. Glaucoma is typically characterized by increased intraocular pressure that can damage the optic nerve, potentially leading to vision loss, but it does not specify loss of vision in one or both eyes as directly as amblyopia does. Esotropia is a form of strabismus where one eye turns inward, potentially affecting visual acuity and alignment but not necessarily leading to a generalized loss of vision. Amblyopia's defining feature of vision loss, especially when identified in children, makes it the correct choice for this question.