Intro/ Development

Question 1

vision testing requirements in CA

Answer 1

• VA upon first enrollment and every 3 years thereafter

- Color vision for boys only upon entry into the first grade

Question 2

what are the AOA guidelines for ages for eye exams?

Answer 2

• by 6 months
• at 3 years
• before 1st grade and every 2 years thereafter

Question 3

what % of children receive an eye exam before 5 years of age?

Answer 3

14%

Question 4

prevalence of amblyopia

Answer 4

2-3%

Question 5

what ethnic group has a higher prevalence of ambylopia

Answer 5

hispanic/latino

Question 6

prevalence of strabismus

Answer 6

3-4%

Question 7

prevalence of refractive error

Answer 7

15-30%

Question 8

prevalence of ocular disease

Answer 8

< 1%

Question 9

prevalence of color vision defects

Answer 9

8-10%

Question 10

what anatomy contributes to young children not being able to see 20/20?

Answer 10

• immature cones (short and stumpy)
• fovea is last area of retina to develop morphologically
• immature visual cortex
• incomplete myelination

Question 11

the VEP method of measuring VA shows what patterns of VA

Answer 11

1mo: 5cpd (20/120)
2. 5mo: 7.8cpd (20/77)
6mo: 18cpd (20/33)
12mo: 25cpd (20/24)

Question 12

about how long does it take for a child to reach 20/20 when measuring VA with preferential looking?

Answer 12

can be up until 3/4 years to see 20/20

requires more cooperation/attention from the child

Question 13

when does contrast sensitivity reach adult like levels?

Answer 13

6-10 years

Question 14

what is unique about accommodation for an infant?

Answer 14

• variable within 1-3 months

- infants have a large depth of focus

Question 15

when does accommodation reach adult like levels for low demands?

Answer 15

~ 3-4 months

but longer latency than adults

Question 16

what is the VOR reflex?

Answer 16

vestibulo-ocular reflex: connection between inner ear to EOMs to maintain fixation with head movement changes

Question 17

what are saccades like in infants

Answer 17

• present at birth

- long latency, wrong direction, short amplitude

Question 18

is stereopsis present at birth?

Answer 18

no

Question 19

when is the onset of stereopsis and when is development spurt?

Answer 19

starts at 3-5 months

-development spurt between 4-6 months

Question 20

when does stereopsis reach adult like levels

Answer 20

~ 2 years old

300 sec of arc

Question 21

when is the “critical period” for binocular development

Answer 21

up to 3 years old

Question 22

when is the “sensitive period” for binocular development

Answer 22

up to 10 years old

Question 23

is binocular fixation and convergence present at birth?

Answer 23

yes

Question 24

most infants are orthotropic at ___ month(s)

Answer 24

1 month

Question 25

when do infants gain fusion

Answer 25

3-4 months

Question 26

when do infants’ binocular fixation and convergence become adult-like

Answer 26

6-7 months

Question 27

what are some conditions that prevent development of the cortical circuits underlying stereoscopic vision (causing amblyopia)

Answer 27

• congenital cataracts
• esotropia
• anisometropia

Question 28

what is unique about the anatomy in the newborn eyes

Answer 28

• shorter eyeball
• really steep cornea
• really powerful lens

Question 29

what changes in the eyes anatomy from newborn to 3-9 months

Answer 29

• cornea loses power
• lose power in lens
• eyeball gets longer

Question 30

the binocular visual field of normal 6 to 7 month old infants was ___% that of the adults

Answer 30

93 %

Question 31

when does color vision emerge

Answer 31

1-3 months

Question 32

VEP studies show what emergence for color vision for the different wavelengths

Answer 32

2 weeks: long and medium wavelengths

5 weeks: short wavelengths

Question 33

when is color vision adult like

Answer 33

3-4 months