FREE COA Visual Assessment and Testing Questions and Answers

Question 1

A patient's uncorrected visual acuity is 20/40. When you have them view the chart through a pinhole occluder, their vision improves to 20/25. What is the MOST likely cause of the patient's reduced vision?

Accepted Answer

Uncorrected refractive error

Answer

The pinhole occluder works by blocking peripheral light rays and allowing only central rays to pass through to the retina, which minimizes the effect of optical imperfections in the cornea and lens. A significant improvement in acuity with the pinhole test strongly indicates that the reduced vision is due to an uncorrected refractive error (like myopia, hyperopia, or astigmatism) that can be corrected with glasses. Vision would likely worsen with macular disease or a central cataract and would not improve in the case of amblyopia.

Question 2

While performing an Amsler grid test on a patient with dry age-related macular degeneration (AMD), the patient reports that the straight lines of the grid appear wavy and distorted. This finding is known as:

Accepted Answer

Metamorphopsia

Answer

Metamorphopsia is the medical term for a visual defect that causes linear objects, such as lines on a grid, to look curvy or rounded. It is a hallmark symptom of macular diseases, including age-related macular degeneration. A scotoma is a blind spot, micropsia is when objects appear smaller than they are, and diplopia is double vision.

Question 3

Which of the following tests is designed to measure a patient's ability to distinguish between different shades of gray and is particularly useful for assessing real-world visual function in low light or glare conditions?

Accepted Answer

Pelli-Robson Chart

Answer

The Pelli-Robson chart is a common method for testing contrast sensitivity, which is the ability to discern objects from their background. This test uses letters of a fixed size that become progressively fainter (lower contrast) down the chart. This differs from standard acuity charts that use high-contrast black letters. Low contrast sensitivity can explain visual complaints in patients with good acuity, especially in situations like night driving.

Question 4

A 75-year-old patient with a dense nuclear sclerotic cataract has a visual acuity of 20/200. The surgeon wants to estimate the potential for visual improvement after cataract surgery. Which test would be most appropriate to perform?

Accepted Answer

Potential Acuity Meter (PAM)

Answer

The Potential Acuity Meter (PAM) is specifically designed to estimate the retinal visual acuity in eyes with media opacities, such as cataracts. It projects a miniature Snellen chart through a clear window in the opacity directly onto the retina, bypassing the cataract to assess the macula's functional capability. This helps set realistic expectations for postoperative vision.

Question 5

When administering the Ishihara color vision test, which of the following is a critical procedural step for ensuring accuracy?

Accepted Answer

Testing each eye individually at a specific reading distance

Answer

Proper procedure for the Ishihara test requires testing each eye separately. The test should be conducted in adequate, daylight-like illumination, at a distance of about 75 cm, and the patient should identify the number within about three seconds per plate without coaching or tracing. These standardized conditions are necessary for a valid assessment of congenital red-green color vision defects.

COA - Certified Ophthalmic Assistant Practice Test

COA - Certified Ophthalmic Assistant Practice Test

FREE COA Visual Assessment and Testing Questions and Answers