Pediatric Ophthalmology

Question 1

Acuity of a newborn is usually ____ and only ____ until the age of 3 and reaches adult level by 3 - 5 years of age

Answer 1

• 20/200 - 20/400
• 20/60

Question 2

what two vision function develop between ages of 3 and 7 months

Answer 2

Stereopsis (perception of depth)
binocular (both eyes)

Question 3

Infants should be able to follow an object by what age?

Answer 3

3 months of age

Question 4

A functional reduction in the visual acuity of an eye, either unilaterally or bilaterally, caused by disuse or misuse during the critical period of visual development

Answer 4

Amblyopia

Question 5

MCC of pediatric visual impairment,
A functional reduction in the visual acuity of an eye

Answer 5

Amblyopia

Question 6

pathophys of Amblyopia

Answer 6

Abnormal vision development in infancy/childhood

• Unilateral or bilateral
• brain receives a poor image from the eye and thus does not “learn to see well”
• Vision loss occurs b/c nerve pathways between brain and eye are not properly stimulated

Question 7

RF amblyopia

Answer 7

1. prematurity
2. FHx of 1st degree relative
3. small size for gestational age
4. neurodevelopmental delay

Question 8

3 classifications of amblyopia

Answer 8

1. strabismus
2. refractive
3. deprivational

Question 9

Misalignment of the visual axes of the two eyes

which type of mablyopia

Answer 9

Strabismus

Question 10

One or both eyes having a refractive error causing an imbalance between the eyes

which type of amblyopia

Answer 10

refractive

Question 11

Obstruction by a cataract or complete ptosis prevents formation of a formed retina

what type of amblyopia

Answer 11

Deprivational

Question 12

One eye may turn in, out, up, or down
Described according to the direction of the deviation

this presentation is for what dx?

Answer 12

Strabismic Amblyopia

Question 13

pathophys of Strabismic Amblyopia

Answer 13

• brain ignores, or “turns off” eye that is not straight and vision drops in that eye
• Occurs because foveas of the two eyes are presented with two different and unfusable images.
• The visual cortex suppresses the image from one eye in order to avoid having diplopia; long-term suppression of one eye results in strabismic amblyopia

Question 14

refractive amblyopia MC occurs as a result of ?

Answer 14

asymmetric refractive error (anisometropia: glasses strength)

Question 15

pathophys refractive amblyopia

Answer 15

• Both foveas are presented with different image clarity d/t unequal uncorrected refractive errors; one eye is not focused on the fovea at the same time as the other
• The brain does not learn how to see well from the eye that has a great need for glasses

Question 16

refractive amblyopia occurs MC in what other vision condition

Answer 16

hyperopic

Question 17

Why is refractive ambolyopia detected at an older age than strabismic amblyopia?

Answer 17

• refractive amblyopia lack obvious external abnormalities and visual functioning appears nml because they see well with the fellow eye
• Often dx at first vision screening when they are old enough to identify letters or figures (ages 4 or 5)

Question 18

• Least common form of amblyopia, but most severe
• It results from vision deprivation, typically a result of interruption of the visual axis or severe **distortion of the foveal image. **

Answer 18

Deprivational Amblyopia

Question 19

what other severe conditions may cause Deprivational Amblyopia

Answer 19

Congenital cataracts, ptosis, congenital corneal opacities, vitreous hemorrhage, and severe refractive errors

Question 20

Deprivational amblyopia in infancy results in _____ if not treated urgently

Answer 20

permanent visual impairment

Question 21

amblyopia evaluation in pre-verbal child

Answer 21

• Fixation reflex: amblyopia will rarely maintain fixation with amblyopic eye when both eyes uncovered
• occlusion objection test: mod-severe - will become more irritable when the other eye with better vision is occluded.

Question 22

testing involves moving a visual target to and from the child’s visual space, each eye being tested by occluding the fellow eye

Answer 22

Fixation reflex

Question 23

Involves monitoring the child’s response to alternate occlusion of the eyes. Children with equal vision respond equally, or not at all to occlusion of either eye.

Answer 23

occlusion objection test

Question 24

amblyopia evaluation in verbal child 3y and older?

Answer 24

1. VA - Allen or Snellen charts
2. Cover
3. Cover/Uncover

Question 25

what line is 20/20 on allen/snellen charts?

Answer 25

7

Question 26

Single best screening device in verbal children Attempt at 3 years of age and older

Answer 26

visual acuity

Question 27

Snellen chart measured at ___ ft and marked off

Answer 27

20 Begin with 20/40 and if child misses two figures in a row, ask the child to go up a row and identify all figures

Question 28

Amblyopia Referral Indications (6)

Answer 28

1. **failed VA** - worse than 20/40 (3-5y) or 20/30 (6y or older) 2. **abnml red reflex** 3. **VA difference** - Difference of greater than or equal to 2 lines between eyes in passing range 4. **asymmetry of vision** 5. **abnml ocular alignment** - Strabismus 6. **unilateral ptosis** - Or other lesions that threaten visual axis, such as hemangioma

Question 29

Amblyopia Treatment? When is intervention the most effective?

Answer 29

1. Most responsive when initiated **before age 7**, with upper range to be effective is 9-10 yrs 1. **Elimination of any visual obstruction** - Cataracts, Hemangioma 1. **Correct any refractive error** - Corrective lenses 2. **use amblyopic eye** - Patching, Corrective lenses, Visual blurring, Surgery

Question 30

4 Strabismus Descriptions

Answer 30

1. Eso - nasal/inward 1. Exo - temporal/outward 1. hyper - upward 1. hypo - downward Tropia: deviation of the eyes

Question 31

Unsteady ocular alignment often sporadically present in newborns until the first few months of life Usually resolves around 3 months of age after child is able to fix and follow which strabismus ddx?

Answer 31

Ocular Instability of Infancy

Question 32

* The apparent esotropia with a wide nasal bridge and/or large epicanthal folds during the first few years of life * Not true strabismus; rather an optical illusion in which the wide nasal bridge or epicanthal folds cover nasal sclera making the eye appear esotropic, particularly when the child looks in lateral gaze which strabismus ddx?

Answer 32

Pseudostrabismus

Question 33

assoc sx of Pseudostrabismus

Answer 33

* Headache * Diplopia * Abnormal head posture

Question 34

PE tests for strabismus

Answer 34

1. corneal light reflex 2. cover test 3. cover/uncover test 4. bruckner red reflex

Question 35

Primary screening technique * Accommodation target using a small toy used w/ ophthalmoscope light standing several feet away. * Hold light and toy in same hand and use the light to reflect on both eyes at the same time what test? what is a normal finding?

Answer 35

Corneal Light Reflex the light reflects off the same position on each eye

Question 36

how to perform cover test? findings? | strabismus

Answer 36

1. child fixates on target at distance or near 1. examiner briefly covers one eye while observing opposite eye for movement * No movement when covering either eye = normal * **eye not occluded shifts to re-fixate on the target** when the fellow, previously fixating eye is covered = **strabismus**

Question 37

how to perform cover/uncover test? findings?

Answer 37

1. Child fixates on target at distance or near. A cover is placed over one eye for a few seconds and then it is rapidly removed. 1. _The eye that was under the cover is observed for refixation movement_ **strabismus**: previously covered eye will shift back into straight-ahead position; when cover is rapidly removed and affected eye is deviated.

Question 38

how to perform Bruckner Red reflex

Answer 38

1. Positioned 18-20 in from child’s face, ophthalmoscope used to visualize both red reflexes at same time 1. light should be positioned just around the skin of the child’s eyes and the child should be looking directly at the ophthalmoscope. The red reflexes should be equal in size, shape, color, and hue

Question 39

Strabismus - Complications

Answer 39

1. Amblyopia 1. Diplopia 1. Secondary contracture of extraocular muscles, limiting extraocular motility and binocular vision fields 1. Psychosocial and vocational consequences

Question 40

Strabismus - Referral Indications

Answer 40

1. Constant strabismus at any age 1. Intermittent strabismus >6mo of age 1. (+) ocular tests 1. Deviations that change with gaze 1. Torticollis not explained by muscle spasm (can be compensatory mechanism to achieve optimal vision in strabismus) 1. Complaints of eye fatigue 1. Prematurity / genetic disorder / metabolic dz 1. Parental concern

Question 41

Strabismus - Treatment

Answer 41

1. **Corrective lenses** - Address vision impairment caused by amblyopia - Refractive error correction with glasses 2. **Patching** - Refractive error correction with patching 3. **Surgery** - _Recession_: Extraocular muscle recession involves repositioning of muscle insertion posterior to the original insertion on sclera = weakens this effect on globe position - _Resection_: shortening the muscle = passive restraint = increasing its effect on globe position