Transcript No Slide Title

CORRELATION OF RETINAL NERVE FIBER LAYER MEASUREMENTS WITH AND WITHOUT CONTACT LENSES MEASURED IN PATIENTS WITH
ASTIGMATISM
Pooja B. Jamnadas MD, Marie Brenner, MS4, Peter Russo, OD, Shuchi Patel MD
Loyola University Medical Center, Department of Ophthalmology, Maywood IL
INTRODUCTION
ABSTRACT
RESULTS
Purpose:
Retinal nerve fiber layer (RNFL) measurements are often used to aid
The purpose is to determine if statistically significant
ophthalmologists in the diagnosis and management of glaucoma. One of
differences exist between retinal nerve fiber layer(RNFL)
measurements and quality (measured in Q value) of optical
accurate measurements. Our study serves to report the effects of contact
without contact lenses. We compared patients with increasing
lenses wear on RNFL measurements. Furthermore we sought to
Methods:
After obtaining IRB approval and consent, patients in the
Loyola eye clinic had their RNFL measured with and without
determine if the degree of refractive error impacts RNFL measurements
or Q values and if the measurements in the axis of astigmatism and 90
degrees from the axis of astigmatism differ.
contact lenses using the Heidelberg Retina Tomograph. The
paired t test was used comparing the average RNFL and Q
done examining the effect of increasing refractive error on the
RNFL and Q value measurements. For patients with
astigmatism, an unpaired t-test was used to compare the
change in RNFL with and without contacts, both in the axis of
their astigmatism and 90 degrees away from their axis of
astigmatism.
Results:
No statistically significant difference is present in RNFL
measurements and OCT quality with or without contact lens
wear overall. Subgroup analysis only found a statistically
significant difference in Q value measurements in patients
between -2.50 and -5.00 of myopia. Subgroup analysis for
increasing refractive error showed no statistically significant
•27 patients that presented to the Loyola eye clinic were recruited for the
study
•Patient’s RNFL was measured with and without their daily contact lenses
in place
•We studied refractive error, RNFL, Q value with and without contact
lenses in place
the axis of astigmatism was also not statistically significant.
•15 eyes had astigmatism
astigmatism compared with measurements 90 degrees from
Conclusions:
We conclude that according to our study there is no statistically
significant difference in OCT RNFL measurements and quality
> -5.00
16
-3.824
-1.371 to 0.8711
-0.1725 to 2.019
-8.565 to 0.9178
0.6332
0.0949
0.1067
Comparison of difference in RNFL measurements with and without contact lenses
RESULTS
subgroup that does show a statistically significant difference
No Contact Lenses
in axis of astigmatism compared to 90 degrees from axis of astigmatism
RNFL measurements in
axis of astigmatism
Number of values
Mean difference in RNFL
measurements with contacts
vs without contacts
Difference between the
means
95% Confidence Interval
P value
30
23.17
RNFL measurements 90
degrees from axis of
astigmatism
30
10.27
12.90
12.90
-21.66 to 47.46
0.4579
-21.66 to 47.46
0.4579
CONCLUSIONS
•For patients with astigmatism, measurements were recorded in the axis
of astigmatism and 90 degrees away
of measurements with and without contact lenses. The only
• Overall, there was no statistically significant difference in RNFL or Q value with and without contact lens wear
• In subgroup analysis with regards to refractive error, the difference in Q value was only statistically significant in
are patients with -2.50 to -5.00 diopters of myopia when
measuring Q value. This subgroup also had the largest number
-2.50 to -5.00
26
0.9231
•Patients were provided appropriate informed consent and made aware
of the risks and benefits of participation
At our institution
measurements with and without contact lenses in the axis of
≤ -2.00
12
-0.25000
•IRB approved, prospective case control study
•Subgroup analysis was conducted with chi square analysis analyzing
whether a refractive error ≤ -2.0, between -2.5-5.0, and >-5.0 diopters
impacted pertinent variables
difference in RNFL measurements. The difference in RNFL
Refractive error
Number of eyes
Mean difference in
RNFL
95% Confidence
interval
P value
METHODS
patient's refractive error, RNFL, and Q value were recorded. A
value with and without contact lenses. A subgroup analysis was
Comparison of RNFL with and without contact lenses
the challenges in measuring RNFL is obtaining good quality scans with
coherence tomography(OCT) studies in patients with and
amounts of refractive error and patients with astigmatism.
Contact Lenses
Comparison of Q value with and without contact lenses
of patients. Therefore we need to extend our study to include
patients with a refractive error between -2.50 and -5.00 diopters of myopia
more patients with higher refractive errors to see if a larger n
will allow for results to reach statistical significance.
Financial Disclosures:
None
Acknowledgements:
The Richard A. Perritt Charitable Foundation
Refractive Error
Number of eyes
Mean difference in
Q value
95% Confidence
interval
P value
≤ -2.00
12
-2.00
-2.50 to -5.00
26
-2.346
> -5.00
16
-0.1250
• In subgroup analysis with regards to refractive error, there was no statistically significant difference in RNFL
-5.851 to 1.851
-4.505 to -0.1873
-3.431 to 3.181
• When examining the difference in RNFL measurements with and without contact lenses in the axis of astigmatism
0.2772
0.0343
0.9369
measurements with and without contact lenses
compared to measurements 90 degrees from the axis of astigmatism, there was no statistically significant
difference in measurements