Transcript Pediatric VA Testing in Developing countries

Barbie O. M. Ejukonemu
Contacts:
1. www.1stopticians.com 2. 080-332-81-569
3. Google ’Dr Barbie Ejukonemu’
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Acuity ---Latin(Acuitas)---- Sharpness
Visual Acuity –an indication of how
well/sharp a person sees.
Measuring Instrument = VA chart
Unit of measurement = Snellen(Feet or meter),
grating(cycle per degree), Decimal and log
MAR
Convertible and reproducible.
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Diagnostic pointer
Follow-up progress on eye disease.
Health records and eligibility for services and
tasks requiring eye sight.
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Visual system functionally least mature at
birth. Infants are “listeners” than “lookers”
Visual deprivation imminent in the event of
eye disease.
Focus on children to facilitate development
and education
A visually impaired child = visually impaired
adult
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System for vision testing not well developed
Detection of ocular abnormalities not well
developed.
Pediatric VA instruments based on advanced
technology.
Technology generally not available/affordable
in developing countries.
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Review visual Acuity testing methods in
children and equip participants with the
capacity and capability to assess vision in
children, emphasising standard , reproducible
tests in the absence of standard instruments.
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Neonates
Infant
Toddler
Pre school
Middle childhood
Adolescence
(Birth to 1mth)
(1mth - 1 yr)
(1yr – 3 yrs)
(3yrs – 6 yrs)
(6yrs – 11 yrs)
(13yrs – 18 yrs)
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Birth – 6mths - Observation, cover tests,
Objection to occlusion, Threat reflex, Fixation,
Following a light, Pupil responses, Grating test
(Lea paddles)
6mths- 3yrs - 100’s and 1000’s, functional vision
test, Lea paddles, Cardiff cards.
3yrs-5yrs - Kay pictures, Illiterate E, Sheridan
Gardiner matching test with Key card, Cardiff
cards
5-6yrs- Sonsken silver tests, snellen test
with/without key cards.
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Newborn
20/300 – 20/400
4-5mths(16-20wks)
20/200
11-12mths(44-48wks) 20/100
1.5-2yrs(72- 96wks)
20/40
3-4yrs
20/30
5-6yrs
20/20
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10wks(2.5mths)
20wks(5mths)
30wks(7.5mths)
40 – 60wks(10- 15mths)
*Cpd = cycle per degree
Cpcm = cycle per centimeter
At 57.2cm 1cpcm = 1cpd
(1—4cpd)*
(2 – 8cpd)
(4-8cpd)
( 4-16cpd)
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12 - 17.9mths
18 – 23.9mths
24 – 29.9mths
30 – 36mths
6/48-6/12
6/24 – 6/7.5
6/15 – 6/7.5
6/12 – 6/6
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Cpm
cpd
snellen
0.25
0.4
0.5
1.0
1.3
4.0
5-3
10.7
13.3
17.3
0.18
0.27
0.36
0.72
0.96
2.9
3.8
7.7
9.6
12.5
6/1000
6/620
6/500
6/250
6/190
6/60
6/50
6/24
6/18
6/14
One of the following is true
for VA testing in Toddlers
a/ Cardiff cards
b. Threat reflex
c/ Sheridan Gardiner
d/Lea Paddles
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Lea Paddles are best indicated for one of the
following age groups
a/ infants
b/ Toddlers
c/ adolescents
d/ neonates
e/ Middle childhood
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The standard Snellen Acuity chart at 6m test
distance is best for
a/ adolescents
b/ middle childhood
d/ deaf adults
e/ all of the above
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6/36 Snellen acuity is equivalent to
a/ 20/120 feet Snellen
b/ 1.0 in Log MAR
c/ 6 degrees Visual angle
d/ b & c above
e/ non of the above.
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2/60 Snellen acuity is equivalent to
a/ 6/180 meter Snellen
b/ 20/600 feet Snellen
c/ 0.03 decimal acuity
d/ 30 degrees visual angle
e/ all of the above.
For
Listening