Testing vision in children

Question 1

At what age should a baby be able to fix and follow a target?

Answer 1

3 months

Question 2

What are 3 things to note abuot fixing and following?

Answer 2

• whether central
• whether steady
• whether maintained when the target is moved

Question 3

How can fixing and following be used to give an estimation of acuity?

Answer 3

Use of different sized targets

Question 4

How can occlusion be used to test babies’ VA?

Answer 4

whether they object to occlusion of one eye more than the other

Question 5

What are Keeler and Teller acuity cards?

Answer 5

comprise series of cards, each of which has black and white grating on a grey background; spatial frequency of grating (i.e. thinness of lines) approximately to different acuity levels

Question 6

What is ‘forced choice’ with Keeler and Teller acuity cards?

Answer 6

cards must be presented so the observer has to decide which direction the child looked before knowing whether this corresponds to the position of the grating

Question 7

What are Cardiff acuity cards?

Answer 7

have vanishing optotpyes - series of pictures with increasing fine outlines, correspondingly difficult to see (can be used as preferential looking test or picture test if verbal)

Question 8

What are 4 types of recogniton tests for older children?

Answer 8

1. Picture tests
2. Keeler logMAR tests
3. Sheridan Gardiner test
4. Sonsken-Silver test

Question 9

What are 3 types of picture tests that can be used for recognition tests for older children?

Answer 9

1. Cardiff acuity cards
2. Kay picture cards (single picture optotypes which vary in size)
3. Multiple picture cards (simliar but multiple optotypes on each card)

Question 10

What are 2 ways to use picture tests?

Answer 10

1. patient selects matching optotype on handheld card
2. child identifies object verbally

Question 11

What are 2 types of Keeler logMAR tests?

Answer 11

crowded and uncrowded

Question 12

At what distance are Keeler logMAR tests performed?

Answer 12

3m

Question 13

What do Keeler Logmar tests consist of?

Answer 13

• optoptypes presented on single line in booklet format
• uncrowded test presents two optotypes of each size on each page, from 0.8 to 0.0
• crowded test presents four optotypes of each size within a rectangular outline (both can be used with a matching card)

Question 14

What is the Sheridan Gardiner test?

Answer 14

5 booklets with single-letter optotpyes which are presented at 6m (or 3m if necessary), intended for use with matching card

Question 15

What is the Sonsken-Silver test?

Answer 15

similar to Sheridan Gardiner test but is a crowded test (multiple optotpyes) - for use with matching card