CPOA Visual Acuity Testing 2 — Questions and Answers
Question 1: What does 20/40 visual acuity mean?
- The patient sees at 40 feet what a normal eye sees at 20 feet
- The patient sees at 20 feet what a normal eye sees at 40 feet (Correct answer)
- The patient has 40% visual loss
- The patient needs a 40-diopter correction
Correct answer: The patient sees at 20 feet what a normal eye sees at 40 feet
20/40 means the patient must be at 20 feet to see what a person with normal vision sees at 40 feet.
Question 2: Which chart is most commonly used for near visual acuity testing?
- Snellen chart
- Tumbling E chart
- Jaeger card (Correct answer)
- Allen picture chart
Correct answer: Jaeger card
The Jaeger card is the standard near vision chart, rated in J-units at a standard reading distance of 14–16 inches.
Question 3: When documenting visual acuity 'cc', what does 'cc' indicate?
- Corrected with contact lenses only
- With correction (cum correctione) (Correct answer)
- Without correction
- With cycloplegic drops
Correct answer: With correction (cum correctione)
The Latin abbreviation 'cc' (cum correctione) means the measurement was taken with the patient's corrective lenses in place.
Question 4: A patient unable to read any letter on the Snellen chart at 20 feet should be tested by:
- Counting fingers at a reduced distance (Correct answer)
- Only using the Jaeger card
- Repeating the test with both eyes open
- Recording VA as 20/200 by default
Correct answer: Counting fingers at a reduced distance
When a patient cannot read the 20/400 line, the examiner tests counting fingers (CF), hand motion (HM), light perception (LP), or no light perception (NLP).
Question 5: The 'pinhole test' is used during visual acuity assessment to:
- Detect color blindness
- Determine if reduced VA is due to a refractive error (Correct answer)
- Measure intraocular pressure
- Assess peripheral vision
Correct answer: Determine if reduced VA is due to a refractive error
The pinhole occluder limits light rays to the central axis, bypassing refractive error; improvement in VA suggests an uncorrected refractive cause.
Question 6: What is the standard testing distance for a projected Snellen chart in most US optometric offices?
- 10 feet
- 14 feet
- 20 feet (Correct answer)
- 40 feet
Correct answer: 20 feet
The standard testing distance in the United States is 20 feet (6 meters), which is considered optical infinity for clinical purposes.
Question 7: A child who cannot identify letters would best be tested using:
- Standard Snellen letters only
- Tumbling E or HOTV chart (Correct answer)
- Amsler grid
- Worth 4-dot test
Correct answer: Tumbling E or HOTV chart
The Tumbling E or HOTV chart uses shapes or a limited letter set that pre-literate children can identify without knowing the alphabet.
CPOA Visual Acuity Testing 2
What does 20/40 visual acuity mean?