Visual Assessment 5%

Question 1

The normal human eye can distinguish 2 points separated by an angle of __________

Answer 1

1 arc minute

Question 2

Each section of the letter E subtends ____________

Answer 2

1 minute of arc

Question 3

The whole letter E subtends _______________

Answer 3

5 minutes of arc

Question 4

In recording VA (US measurements) Numerator=

Answer 4

Top number, Distance (in feet) pt is from chart

Question 5

*In recording VA (US measurements) Demominator=

Answer 5

Bottom number. Distance (in feet) that someone with normal vision could correctly read the letters.

Question 6

When checking VA, the larger the number___________

Answer 6

the worse the vision.

Question 7

How to convert feet to meters

Answer 7

3:1 ratio
6m=20ft
1m=3.28

Divide denominator by 3 to get approx meters. (Or drop the 0 and multiply the first number by 3. Ex. 20/40=6/12(2x3 is 6 and 4x3 is 12))

Question 8

Convert to meters…
20/60

Answer 8

6/18

Question 9

Convert to meters…
20/400

Answer 9

6/120

Question 10

Convert to meters….
20/30

Answer 10

6/9

Question 11

What do you do if pt can’t see 20/400 E?

Answer 11

Have pt move toward the chart until he can read 20/400E
Example charting 4/400 (pt 4’ away from screen, read 400 line)

Question 12

If pt cannot distinguish the 20/400 E even from close distance what are the next steps?

Answer 12

Hold you one or two fingers up in from a distance of 5’
Move 1’-2’ closer until pt can accurately count your fingers
Record as CF(count fingers) @_______

Question 13

If pt cannot count fingers…….

Answer 13

Move your hand side to side or up and down in front of eye.
Ask..”am I moving my hand up and down or side to side?”
If s/he can accurately perceive your hand moving record HM(hand motion) @___

Question 14

If pt can’t accurately detect HM…….

Answer 14

Darken Room
Project transillumintor from 1”(be sure to keep fellow eye covered). Check all 4 quadrants.
If pt can’t see transilluminator, use indirect ophthalmoscope and try again.
Record as LP with proj or Light percetion with projection.
If pt can’t accurately detect the position of the light but CAN perceive the light record as LP or Light perception.

Question 15

If pt is unable to perceive light…..

Answer 15

Record….Absent Light perception, No light perception, or NLP

Question 16

When checking VA 3 month old should be able to _________
4-6 mos old should be able to _________

Answer 16

Follow light
Reach for toy

Question 17

When checking VA of Pre-verbal Pts…..

Answer 17

3 mos to 2 years old
-observe patient’s gaze
-Cover each eye seperately and see if pt focuses on a light. (Fixates & Follows)
-Eccentric fixation but steady+Probably ,NL
-Unsteady and eccentric fixation=VA probably extremely poor and eye defective.

Question 18

What does CSM stand for when evaluating fixation in infants?

Answer 18

CSM=Central, Steady, Maintained

Question 19

What does CSUM stand for when evaluating fixation in infants?

Answer 19

CSUM=Central, Steady, Un-Maintained

Question 20

What does CUSUM stand for when evaluating fixation in infants?

Answer 20

CUSUM=Central, UnSteady, Un-Maintained

Question 21

What does UCUSUM stand for when evaluating fixation in infants?

Answer 21

UCUSUM=UnCentral, UnSteady, Un-Maintained

Question 22

What vision chart is best for pre school children age 2+ and mentally challenged older children or illiterate adults, used in school screenings, 30’ denominator, shows pictures at close range with OU open then one eye, pictures presented while backing away. You record greatest distance at which 3 pictures are accurately identified in each eye. If difference of VA is >5’ refer to doctor for eval.

Answer 22

Allen Picture Chart

Question 23

This vision chart is for Pre school children an 2+ and illiterate adults. Pt points their finger or plastic E in the direction of the E on the chart. Pt should practice before beginning.

Answer 23

Tumbling E’s

Question 24

This vision chart is good for illiterate and pre school children. Pt identifies where the break is in the letter C.

Answer 24

Landolt’s Broken Ring Test

Question 25

*This vision chart is good for young or mentally challenged children or adults with a language barrier. Measures Near and Distance VA. Used at 10' or 20'. Pt is given corresponding key chart and asked to hold the chart to identify the corresponding letter.

Answer 25

Sheridan-Gardiner Test (Matching Test)

Question 26

*PAM uses ________light source.

Answer 26

Pinpoint

Question 27

PAM uses an illuminated __________chart.

Answer 27

Snellen

Question 28

_____________test uses pattern of stripes. Red or white separated by black stripes of equal width. Width of stripes can be changed. Present vertical & horizontal lines first assess VA, then present oblique lines. Pt is asked to state orientation of each grid while the width of stripes are changes. This test is similar to PAM but uses stripes.

Answer 28

Laser Inferometer Test.

Question 29

Visual Acuity________. Is standard eye chart accepted in studies sponsored by the National Eye Institute. Adopted from Early Treatment of Diabetic Retinopathy Study. Designed for use in clinical studies and low vision evaluations where accurate and repeatable visual acuity measurements are required. Geometric progression in letter size from line to line, each line is of equal difficulty.

Answer 29

ETDRS

Question 30

This vision chart is used for Pre school ages 3-7. Has video Acuity Tester with monitor, software and hand controller. Is calibrated at 3 meters. Uses high contrast black and white letter ( H O T & V). Single letters are framed with crowding bars spaced a letter width around the letter.

Answer 30

EVA (Electronic Visual Acuity)

Question 31

Children should be able to follow light by age….

Answer 31

3mos

Question 32

Children should be able to reach for you by age…..

Answer 32

4-6 mos

Question 33

Used to check VA in infants and pre verbal patients. Uses vertical black and white stripes. High contrast images.

Answer 33

Teller Acuity Cards

Question 34

Measurement of VA in poor contrast conditions.

Answer 34

Contrast sensitivity testing

Question 35

Test that uses charts and machines, stripes of varied contrast, size, orientation, done at near and distance, and is more reliable than Snellen.

Answer 35

Contrast sensitivity test

Question 36

When should contrast sensitivity testing be done?

Answer 36

With cataracts, refractive sx, glaucoma, AMD, CL fitting.