Color Vision 5

Question 1

This type of color deficiency means absence of color.

Answer 1

Achromatopsia

- very rare

Question 2

Incomplete achromatopsia has what type of PRs left? Complete?

Answer 2

• Long and M cones (reduced function)

- Only rods present

Question 3

What is the tx for achromatopsia? What does it prevent?

Answer 3

• Dark Red Lenses

- Prevents rod bleaching and helps with photophobia

Question 4

What PRs are functional in blue monochromacy?

Answer 4

• rods and S-cones

Question 5

What is the treatment for blue monochromacy?

Answer 5

Magenta Glasses

Question 6

This is a disturbance of vision where colored objets appear unnaturally colored. Usually following cataract extraction or drug use.

Answer 6

Chromatopsia (not a true color vision anomaly)

Question 7

Color Anomalies are caused by what?

Answer 7

cross-overs of genetic information during meiosis

Question 8

What is the less severe type of crossover? Inter or intragenetic?

Answer 8

Intragenetic = only part of the gene crosses over (hybrid);
Intergenetic = entire gene grosses over; more severe

Question 9

Acquired color deficiencies can occur ______ along the visual pathway.

Answer 9

anywhere

Question 10

Kollner’s rule states what?

Answer 10

BY defects = outer retina or media changes

RG defects = diseases of the conduction pathway (inner retina to visual cortex)

Question 11

If patient has non-selective color vision loss (both RG and BY), what disease are you worried about?

Answer 11

Multiple sclerosis

- optic neuritis (but typically RG)

Question 12

In glaucoma, early color vision losses are what defect?

Answer 12

Blue yellow

Question 13

Tritan-like defects are found in what 3 ocular diseases?

Answer 13

1. ARMD
2. Central Serous Retinopathy
3. Diabetic Retinopathy

Question 14

Digoxin/Digitoxin produces what type of defect?

Answer 14

RG

Question 15

Viagra produces what type of defect?

Answer 15

BY

Question 16

Chloroquine produces what type of defect?

Answer 16

1. BY initially

2. Protan defect later

Question 17

Ethambutol produces what type of defect?

Answer 17

RG

Question 18

Industrial chemical produces what type of defect?

Answer 18

BY

Question 19

Which cone is more vulnerable to disease?

Answer 19

S cones

Question 20

SWAP is great to use for glaucoma because?

Answer 20

• S-cones are damaged first
• only make up 5% of ganglion cells
• if few are damaged, easier to detect

Question 21

What are the 2 ways that filters work?

Answer 21

1. move color confusion lines

2. block specific wavelengths

Question 22

An X-chroma lens improves color vision by doing what 2 things?

Answer 22

1. lets long wavelengths through filter

2. Blocks shorter wavelengths

Question 23

What effect does an X-chroma lens have on a monochromat? dichromat?

Answer 23

1. monochromat becomes dichromat

2. dichromat becomes tetrachromat

Question 24

The enchroma lens improves color vision by doing what 2 things?

Answer 24

1. Separates M and L wavelengths to increase color perception
2. blocks some wavelengths

Question 25

What is the only lens that is FDA approved to treat dyslexia?

Answer 25

Chromagen Lenses

Question 26

These type of lenses corrects RG defects by amplifying oxygenation of blood under the skin.

Answer 26

Oxy-Iso glasses

Question 27

The luminance function peak for deuteranopes is similar to who?

Answer 27

Trichromats