10- Peds LV

Question 1

What is the who definition of legal blindness?

Answer 1

Uncorrected acuity of 20/400 or worse

• not 20/200 b/c it’s based on the UNDERPRIVELEGED world (hence, the fact that they’re uncorrected)
• you’re thinking 20/200 or worse in the better seeing eye…not the same.

Question 2

What is the leading cause of pediatric vision impairment worldwide (including developed and under developed countries)?

-due to what reasons?

Answer 2

Corneal blindness (350,000/yr)-most die w/i a yr of blindness onset

-Vit A deficiency (peak b/w 3-5Y/O), post-infectious, trauma, congenital dz, traditional med/home remedies

Question 3

Leading cause of pediatric visual impairment in developed world?

Answer 3

Cerebral/cortical impairment

Question 4

As it relates to vision educator services which of the following is true?

Answer 4

Services are available from early intervention and beyond

early intervention: birth-3
preschool: 3-5
grade school/beyond: end age depends - Maine is 20Y/O

Question 5

T/F: reporting print size is not a sufficient recommendation

Answer 5

TRUE - should recommend it, not determine (as in, require,) it

Question 6

T/F: ODs determine print size?

Answer 6

FALSE - we recommend it, NOT mandate it

Question 7

T/F: Devices are all that’s needed for proper learning of a LV pt

Answer 7

FALSE

Question 8

-Do children w/ visual impairment usually have other impairments/disabilities? About what percentage?

Answer 8

yes; typically…about 2/3rds

Question 9

T/F: readiness for braille needs to be evaluated in a pediatric LV evaluation

Answer 9

FALSE - but ODs should look for: the impact of crowding, contrast, and numerous aspects of visual based communication system

Question 10

T/F: individuals w/ CVI rarely improve on their own

Answer 10

FALSE - they CAN improve on their own (or w/ medical intervention)

Question 11

Once found, are null points (in strabismus) typically stable?

Answer 11

NO, not usually. They CAN change overtime, and can even differ b/w dist. and near.

Question 12

What is the no. 1 OVERALL leading cause of blindness/vis. impairment worldwide?

Answer 12

cataracts

Question 13

leading cause of congenital glaucoma in peds population (I’m assuming worldwide)?

Answer 13

rubella!

Question 14

list some forms assistive technology - and some things they do:

Answer 14

1) assistive devices: lessens functional limitations
2) adaptive technology: substitutes/makes up for the loss of fxning from a disability
3) augmentative devices: augments a specific fxn (ie. aid speech understanding w/ a microchip voice output device)

Question 15

Bardet-Biedl is an example of a __-__ dystrophy.

• Associated with…
• Night blindess by…
• Legal blindess by ~___…Y/O

Answer 15

rod-cone dystrophy –> 90% AR

assn: truncal obesity, polydactyly, genitouinary & renal malformations
- night blind by 7, legally blind by ~15
- other eye findings: nystagmus, strab, high myopia, cataracts, glaucoma

Question 16

greater than a ___ line difference on contrast cards such as the double happy, lea, and colenbrander cards indicates a potential problem

Answer 16

two

Question 17

Stargardt’s disease

• inheritance pattern?
• first causes visual loss in what area of the VF? In what decade of life?

Answer 17

AR; first-second decade of life

• CENTRAL acuity loss - initially 20/60 but will end up 20/200 or worse
• loss of RPE support - leads to retinal PR death

Question 18

What size text do we initially consider as a STARTING POINTi for text size adjusted for working distance?

Answer 18

2-3 times the threshold acuity

Question 19

four classifications of vision loss (OOCC)

Answer 19

Ocular: eye structures to chiasm
Oculomotor: brainstem, cerebellum
Cortical: primary pathway (post-chiasm to occipital/V1)
Cerebral: post-occipital, complex processing/temporal & parietal & frontal

Question 20

What type of nystagmus is typically seen in albinism?

Answer 20

pendular - specifically, oculo-cutaneous albinism

Question 21

what is the SINGLE MOST POWERFUL therapeutic intervention for improving vision and visual fxn in many LV/VI pts?

Answer 21

correction of significant REFRACTIVE ERROR

Question 22

Kestenbaum method of surgical intervention has been proposed for when the null point needs to be shifted how?

Answer 22

Vertically OR horizontally

Question 23

If you’re going to Rx yoked prisms to a pt whose eyes are UP, what prism base direction will you select?

Answer 23

base DOWN - shifts image up to where the eyes are already pointing- (weiss & brown suggest 6PD each eye to start)

Question 24

ONH hyperplasia is considered an ____ cause (one of those four groups) of vision loss

• Can you predict what the vision is based on how much of the nerve has been lost/its size?
• T/F: this person’s color vision will likely be abnormal.

Answer 24

ocular (recall: eye structures to chiasm)

NO, you can’t predict based on nerve size

-FALSE - somehow, these pts (specifically w/ ONH hyperplasia) have NORMAL CV.

Question 25

What are the three phases of brain development? [ICS]. Part of WHICH group of vision loss?

Answer 25

cortical: post-chiasm to V1
- I: induction - days 1-60
- C: cellular proliferation - days 61-24wks
- S: synapse formation - 25wks-4yrs

Question 26

Name some characteristics based on the Roman-Lantzy scale of cortical visual impairment (CVI)

Answer 26

color preference, need for mvmt, visual latency, VF preference, difficulties w/ vix. complexity, light gazing/nonpurposeful gaze, difficulty w/ dist. viewing, atypical visual reflexes, difficulty w/ visual novelty, absence of visually-guided REACH

• each item scored on scale of 0-1, 1 meaning the factor is no longer an issue affecting their visual function - score up to 10
• intervention is based on the score

Question 27

What are the three stages of intervention in the Roman-Lanzky scale of CVI?

Answer 27

1) building visual behavior
2) integrating vision w/ fxn
3) “resolution” of CVI characteristics

Question 28

ventral stream: the ___ stream
-in which two main lobes?

dorsal stream: the __ stream
–in which two main lobes?

-in cerebral and ocular visual impairment, WHICH stream’s dysfunction is more common?

Answer 28

ventral - what (pumping chest) - temporal, occipital lobes

dorsal - where - posterior parietal, middle temporal

-DORSAL more common - difficulty w/ VF/visual attn when moving, visually guided movement, crowded env, etc.

Question 29

Three characteristics of cerebral visual impairment (CVI)?

Answer 29

1) variably reduced central acuity
2) dorsal/ventral stream dysfxn
3) possibly reduced VF