RR: Computer Vision Syndrome

Question 1

What are the ocular findings related to computer vision syndrome?

Answer 1

1. Eyestrain/Eye Fatigue
2. Burning Sensations/Irritation
3. Redness/Dry eyes

Question 2

What % of US workers using a computer over 3hrs/day experience CVS (computer vision syndrome)?

Answer 2

90%

Question 3

What are the non-ocular (ergonomic) symptoms associated with CVS?

Answer 3

1. Headache
2. Pain in shoulders/wrist
3. Pain in Neck
4. Pain in back

Question 4

What are the 3 pathophysical causes of CVS?

Answer 4

1. Ocular surface mechanisms
2. Accommodative mechanisms
3. Extraocular mechanisms

Question 5

Prolonged computer (VDT) use causes what 3 accommodative/covergence findings?

Answer 5

1. Less power of accommodation
2. Removal of NPC
3. Deviation of phoria for near vision

Question 6

Patients below the age of 40 who use VDTs lost _____ (more/less) accommodation amps than those who did not.

Answer 6

Lost more accommodation

Question 7

Gur and Ron found a high prevalence of what 3 things a the end of the day, 4 days later?

Answer 7

1. exophoria
2. Convergence insuffiency
3. Low fusional convergence

Question 8

What type of shift do VDTs cause? How much?

Answer 8

myopia, 0.12D

Question 9

Blink rate is decreased further in a dark setting. What % is it reduced?

Answer 9

60%

- more in post-menopausal women

Question 10

What’s the normal blink rate?

Answer 10

10-15x a minute

Question 11

T/F: Upper and lower case documents are easier to read than all uppercase.

Answer 11

True

Question 12

What was used to help schoolchildren with myopia that report visual changes after 30 mins of computer usage.

Answer 12

Screen filters

Question 13

Extemely low refresh rates (flicker) can cause what?

Answer 13

epileptic seizures

Question 14

Lower refresh rates means _____ is weaker and blink rates were _____.

Answer 14

• accommodation was weaker

- blink rates were lower

Question 15

What type of lamp is best used to decrease visual asthenopia?

Answer 15

Sodium lamps

Question 16

Where should a computer be placed to reduce symptoms?

Answer 16

35-40 inches

Question 17

How much tilt should a computer screen have?

Answer 17

10-20degrees

Question 18

Studies show a person should take regular work breaks every __ hours.

Answer 18

4 hours

Question 19

One of the most simple and therapeutic modes of therapy are _____.

Answer 19

Lubricating eye drops

Question 20

What are the accommodative symptoms of CVS?

Answer 20

1. AI (Near blur)
2. Accom. Infacility (slow focus from dist/near vice versa)
3. Acc. Spasm (blur at distance after near)
4. Fatigue/Eyestrain (can’t sustain near work)

Question 21

What is the basis of CVS?

Answer 21

1. Extended near point demand
2. Poor resolution/contrast
3. dark background of computer screen

Question 22

What happens to accomodation in upgaze?

Answer 22

Decreases

Question 23

How much does accommodation decrease in upgaze at 20’, 30’ and 60’

Answer 23

20’ = reduced by 1.25D
40’ (straight ahead) = reduced by 2D
60’ (cpu sits 20’ up) = reduced by 3D

Question 24

What are the causes of dry eyes at the computer?

Answer 24

1. Decreased blink rate (1/3 of usual)
2. Increased exposure
3. dry office environment

Question 25

What's the normal, reading and computer blink rate?

Answer 25

``` Normal = 22/min Reading = 10/min Computer = 7/min ```

Question 26

What does a technica american optic offer as a progressive lens design? What does this lens specify?

Answer 26

- enhanced midrange and near lens design(small distance area) - specifies distance Rx and add power

Question 27

How should the head be positioned when looking at a computer?

Answer 27

Head back, chin tucked, ears shoulder and hips aligned

Question 28

How should the elbows be positioned when looking at a computer?

Answer 28

At sides - slightly more than 90 degree bend

Question 29

How should the eyes be positioned when looking at a computer?

Answer 29

Level with top 1/3 of screen; 18-24in away

Question 30

When working on the computer, how many times should one take a break?

Answer 30

Every 30 mins

Question 31

What are some suggestions to decrease effects of CVS?

Answer 31

- 20-20-20 rule - Size up - Sharpen up - Reduce glare (good lighting) - Look down (easier to focus) - Think blink more

Question 32

The asthenopic symptoms of eyestrain and tired eyes from CVS are diagnosed as wht?

Answer 32

Binocular Vision and Accommodative issues

Question 33

It is important to specify what Rx while prescribing the Readables Varilux lens?

Answer 33

Specify computer Rx

Question 34

It is important to specify what Rx while prescribing the Access Sola lens?

Answer 34

Specify near Rx

Question 35

The Shamir Office Occupational lens is best used in what environment? How many powers are there to choose from?

Answer 35

- best in small office environments | - 4 different powers to choose from