Retinoscopy/Refraction

Question 1

What is static retinoscopy?

Answer 1

Control for accommodation (cycloplegia, fog, distance fixation)

Question 2

What is dynamic retinoscopy?

Answer 2

Does not control accommodation, often used to determine the near Rx

Question 3

How can you perform infant retinoscopy?

Answer 3

Loose lenses or skiascopy, cyclopligia, finger puppet or light for target

Question 4

Why and how is cycloplegia used in infant ret?

Answer 4

Preferred due to the robustness of accommodative response and small pupil size, infants use 0.5% cyclopentolate (1% tropicamide 2nd choice), 12 months + 1% cyclopentolate

Question 5

What is Mohindra near ret?

Answer 5

Technique for assessment of distance refractive error, has good correlation with cycloplegic results

Question 6

What is the Mohindra technique?

Answer 6

Dark room, infant fixates on ret light at 50 cm, determine magnitude of with/against with skiascopy bars, then subtract 1.25 D from result

Question 7

What techniques are used for toddler/preschool ret?

Answer 7

Loose lenses or skiascopy bars

Question 8

How is toddler/preschool ret performed?

Answer 8

Movie as fixation target, ret and trial frame the results

Question 9

When is cycloplegia indicated for toddlers/preschoolers?

Answer 9

Decreased VA, esotropia, high hyperopia or a variable reflex

Question 10

What cycloplegia is used of toddler/preschooler?

Answer 10

Cyclopentolate 1% is a wet refraction (tropicamide 1% is damp because not full cycloplegia)

Question 11

At what age can a child sit in the phoropter?

Answer 11

8+

Question 12

What is the indication for cycloplegia in school aged ret?

Answer 12

Decreased VA, esotropia, variable reflex

Question 13

Can school aged children understand JCC?

Answer 13

Normally yes

Question 14

What is the average refractive error of full term newborns?

Answer 14

+2.00, 88% between Plano and +4

Question 15

What is the standard deviation for refractive error of full term newborns?

Answer 15

2.00 +/_ 2.75

Question 16

What percent of full term newborns have astigmatism?

Answer 16

30%

Question 17

What is emmetropization?

Answer 17

Tendency for the refractive state of the eye to change close to plano, converges to low hyperopia

Question 18

What is the standard deviation after emmetropization?

Answer 18

+0.50 to -1.00 +/- 1.00

Question 19

Theories of active emmetropization?

Answer 19

Regulated by retinal image- eye interprets retinal blur and adjusts, sustained near vision and myopia, animal studies make functional myopia/hyperopia, eye is growing/increase axial length

Question 20

What is the evidence for emmetropization regulated by retinal image?

Answer 20

Media opacities ROP, myopia more common

Question 21

What is the “evidence” for sustained near vision and myopia?

Answer 21

Law students/jewelers

Question 22

What are theories of passive emmetropization?

Answer 22

Physical changes- refractive errors move to emmetropia initially, genetics affect Rx, changes in corneal/lenticular power

Question 23

How do genetics contribute to passive emmetropization?

Answer 23

If both parents are myopic you have a 42% chance, if one is you have a 22.5% change, if neither is you have an 8% chance

Question 24

What could changes in corneal/lenticular power be in response to?

Answer 24

Increase axial length, creates balance for emmetropization

Question 25

What are the structural changes of emmetropization?

Answer 25

Crystalline lens adds layers, increase net weight, and flattens; corneal power decrease, axial growth occurs

Question 26

What does the BIBS study stand for and when was it conducted?

Answer 26

Berkeley Infant Biometry Study 2009

Question 27

How many infants participated in the BIBS study and at what ages?

Answer 27

262 infants, ages 3, 9, and 18 months

Question 28

What was the body weight for the BIBS study?

Answer 28

>2500 g

Question 29

What test did BIBS conduct?

Answer 29

Cycloplegic, near and Mohindra ret, visual acuity

Question 30

What did the BIBS study find?

Answer 30

bidirectional emmetropization

Question 31

What was the best predictor in the BIBS study?

Answer 31

Cycloplegic refraction

Question 32

Higher magnitude = _____ likely to be emmetropized at 18 months

Answer 32

Less

Question 33

T/F large amounts of astigmatism are common in children < 3 years old

Answer 33

True, +1 D in 30% of newborns

Question 34

Which is more common in <3 years old, WTR or ATR?

Answer 34

ATR

Question 35

When is astigmatism highest and when does it reach adult levels?

Answer 35

Highest in the first two years, adult levels by age 4-5

Question 36

T/F if little astigmatism in 1st year of life, not likely to acquire

Answer 36

True

Question 37

What is MEPEDS and when was it?

Answer 37

Multi Ethnic Pediatric Eye Disease Study 2011

Question 38

What did MEPEDS look at?

Answer 38

Astigmatism in children ages 6-72 months

Question 39

What did MEPEDS find?

Answer 39

>1.50 D astigmatism in 16.8% of Hispanic children and 12.7% AA; >3.00 D astigmatism in 2.9% of Hispanic and 1% AA

Question 40

T/F the majority of the astigmatism found in MEPEDS was WTR and decreased with age

Answer 40

True

Question 41

What percent of preschoolers failed an exam two times in LA?

Answer 41

18%

Question 42

How many preschoolers had vision screenings in LA?

Answer 42

56%

Question 43

What percent of preschoolers in LA had myopia >-0.50 D?

Answer 43

20%

Question 44

What percent of preschoolers in LA had hyperopia >+0.50 D?

Answer 44

59%

Question 45

What percent of preschoolers had astigmatism > -1.50D in LA?

Answer 45

66%

Question 46

Which ethnicity was the least hyperopia and which was the most?

Answer 46

Least-Asian, most-white

Question 47

Which ethnicity had the most astigmatism?

Answer 47

Latino (68%) AA (61%)

Question 48

Most children starting school (5-7 years old) have ____ refractive error

Answer 48

+0.50 to +3.00 refractive error

Question 49

When is the lowest prevalence of myopia?

Answer 49

5-7 years old

Question 50

T/F 5-6 year olds with plano to +0.25 D are likely to become myopic by teenage years

Answer 50

True

Question 51

Do girls or boys become myopic faster?

Answer 51

Girls

Question 52

T/F refractive error changes faster in children with myopia than hyperopia

Answer 52

True