Reliability of Aberrometry in Prescribing Glasses for the Undilated
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Transcript Reliability of Aberrometry in Prescribing Glasses for the Undilated
Reliability of Aberrometry Versus Cycloplegic Retinoscopy in
Prescribing Glasses to Undilated Child
S.A. Erzurum, MD FACS
Aylin Sarac
Financial Interest
The authors have no financial interests in
any of the topics discussed in this study.
Purpose of Study
Retinoscopy is a difficult skill for many eye care
professionals.
Children are a difficult subpopulation for eye care
professional to refract.
Inaccurate glass prescribing occurs for many children.
Dilation necessary for accurate refraction but disliked by
children and family.
Purpose of Study
Find a reliable method for non-specialized eye
care providers to prescribe glasses for children.
Reliable method should be easy and quick.
Find method that eliminates/reduces need for
dilating drops to check refraction.
Method
iZON Aberrometer was machine used for comparison to
cycloplegic refraction.
Images are taken before dilation.
Child sits upon parent’s lap and multiple rapid images are
obtained.
Immediately upon taking image, analysis is provided of
sphere, cylinder, axis, level of aberrations, and quality of
image.
Example of reliable image
capture.
Prescription measured and
reported as sphere, cylinder,
and axis.
Aberrations measured and
reported in green, yellow or
red.
Pictures demonstrate how
patient sees at night.
Example of poor
image and unreliable
readings.
No measurements are
provided for aberrations.
Whatever prescription was
captured is reported, but
may not be reliable.
Example of right eye with poor
image capture and left eye with
excellent capture.
Right eye results for refraction
may not be reliable.
Left eye results reliable.
Method
Prospective consecutive series of 256 eyes in 128
pediatric patients involved in full exam.
Age range of 3 to 18 years.
iZON aberrometer images prior to dilation.
Full eye exam with cycloplegic refraction.
No patients were excluded, and all were examined by the
same pediatric ophthalmologist.
Results
CYCLOPLEGIC
(mean +/- SD)
Sphere
0.42 + 2.95
Astigmatism 0.74 + 0.91
Spheric equiv 0.75 + 2.91
ABERROMETER
(mean +/- SD)
-0.05 + 2.16
0.92 + 1.52
0.39 + 2.17
Age (mean + SD) 8.1 + 3.2 years; Mode 7 years
Range 3-18 years
Female
Male
62
66
48.4%
51.6%
Prevalence of Eye Disorders in Study Patients
Prevalence of Eye Disorders
–
–
–
–
–
–
–
–
–
–
–
Normal
Esotropia
Amblyopia
Exotropia
Cerebral palsy/
developmental delay
Congenital nystagmus
Cataracts
IDDM
Duane’s
Best’s
Coloboma
120
32
29
9
7
4
3
4
3
1
1
46.9
11.3
12.5
3.5
2.7
1.6
1.2
1.6
1.2
0.4
0.4
Reliability of Aberrometer
Only 45 eyes of 256 (17%)had an unreliable reading and
were excluded from comparison.
26 eyes of these 45 (64%)had ocular pathology which
would have directed them to sub-specialized care.
Immediately upon taking image, examiner is aware of
reliability of image.
Results of Comparison between two Methods
Comparison between aberrometer and cycloplegic results
were made in each area of sphere, cylinder, and axis.
In all categories, correlation was high between the two
methods.
Offset and slope of the best fit regression were calculated
for each.
All comparisons showed the slope was very close to 1.
Y cyclo sphere = 1.04 X izon sphere + 0.469
Model ANOVA F = 1552.93, p < 0.001
R = 0.934
Y cyclo SPHEQ = 1.019 X izon SPHEQ + 0.400
Model ANOVA F = 718.782 p < 0.001
R = 0.865
Y cyclo astig = 0.909 X izon astig – 0.026
Model ANOVA F = 766.735 p < 0.001
R = 0.887
Sphere
Astigmatism
Spherical
Equivalent
Conclusions
iZON aberrometer is a reliable method of refraction to
assist practitioners uncomfortable with cycloplegic
refraction in children.
iZON aberrometer gives a reliable reading and a high
correlation with cycloplegic refraction.
Group of patients who showed higher unreliability by
aberrometry measurements had a higher chance of
ocular pathology.