Are Network Results Regarding Ocular Coherence Tomography OCT Relevant to Clinical Practice and Clin

1
Are Network Results Regarding Ocular Coherence
Tomography (OCT) Relevant to Clinical Practice
and Clinical Trials?

• Sponsored by the National Eye Institute,
• National Institutes of Health, U.S. Department of
  Health and Human Services.

2
Comparison of CPT VA at Baseline (A)
0
Correlation
r 0.52, N 251
20
(20/400)
40
(20/160)
VA (Letter Score)
60
(20/63)
80
(20/25)
100
0
200
400
600
800
1000
OCT CPT (Microns)
3
Comparison of CPT VA at Baseline (A)
0
Correlation
r 0.52, N 251
20
(20/400)
40
(20/160)
VA (Letter Score)
60
(20/63)
80
(20/25)
100
0
200
400
600
800
1000
OCT CPT (Microns)
4
Comparison of CPT VA at Baseline (A)
0
Correlation
r 0.52, N 251
20
(20/400)
40
(20/160)
VA (Letter Score)
60
(20/63)
80
(20/25)
100
0
200
400
600
800
1000
OCT CPT (Microns)
5
Comparison of Change in OCT CPT and Change in VA
from Baseline to 3.5 Months
25
Thinner / Visual Acuity Better
20
Thicker / Visual Acuity Better
(Paradoxical Change)
15
10
5
0
Change in VA (Letter Score)
-5
-10
Thinner / Visual Acuity Worse
-15
Thicker / Visual Acuity Worse
(Paradoxical Change)
Correlation r 0.44, N 185
-20
-25
-250
-200
-150
-100
-50
0
50
100
150
200
250
Absolute Change in OCT CPT (Microns)
6
Comparison of Change in OCT CPT and Change in VA
from Baseline to 3.5 Months
25
Thinner / Visual Acuity Better
20
Thicker / Visual Acuity Better
(Paradoxical Change)
15
10
5
0
Change in VA (Letter Score)
-5
-10
Thinner / Visual Acuity Worse
-15
Thicker / Visual Acuity Worse
(Paradoxical Change)
Correlation r 0.44, N 185
-20
-25
-250
-200
-150
-100
-50
0
50
100
150
200
250
Absolute Change in OCT CPT (Microns)
7
Summary

• There is a modest correlation of OCT measured CPT
  with VA in eyes with diabetic macular edema (DME)
• There is a wide range of visual acuities for a
  given CPT
• There is a modest correlation of changes in
  retinal thickening and VA after focal laser
  treatment for DME
• OCT measurement alone may not be a good surrogate
  for VA as a primary outcome in studies of DME

Diabetic Retinopathy Clinical Research Network.
Relationship between optical coherence
tomography-measured central retinal thickness and
visual acuity in diabetic macular edema.
Ophthalmology 2007114525-36
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Other OCT Findings
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A Real Change in ThicknessOCT Diurnal
Variation Study (C)
10
Summary

• Change in central subfield thickness exceeding
  11 is likely to be real
• Replicate measurements of central subfield differ
  by a median of 2 in patients with DME
• Retinal thickness reproducibility in microns
  varies according to the degree of thickness

Diabetic Clinical Retinopathy Clinical Research
Network. Reproducibility of macular thickness and
volume using Zeiss optical coherence tomography
in patients with diabetic macular edema.
Ophthalmology 20071141520-5
11
Relationship of Error Rate by Scan Proportion
Sent to RC Based on Center Point SD
16
14
Never Send
12
10
SD gt 10
8
SD gt 9
Error Rate
SD gt 7
6
SD gt 5
4
SD gt 3
2
0
0
20
40
60
80
100
Scans Sent to Reading Center
12
Summary

• In DME trials, error involved with automated OCT
  CPT measurement is sufficiently small that
  results are not likely to be affected if scans
  are not routinely sent a reading center
• Greater degree of accuracy requires sending only
  about 1/3 of scans to the RC for assessment.

13
Mean Retinal Thickness According to Gender in
Diabetic Subjects with Minimal or No Retinopathy
(G)
14
Mean Retinal Thickness Minimal or No
Retinopathy (G)
15
Summary

• OCT measured thickness in diabetic subjects
  without retinopathy are similar to central
  subfields OCT data in non-diabetic subjects
• The nasal inner and outer zones are thicker than
  the temporal inner and outer zones

16
Summary

• The average central subfield is thicker in men
  than women.
• Gender differences are large enough to consider
  separate norms by gender when designing clinical
  trials evaluating DME based on OCT

Retinal thickness on Stratus optical coherence
tomography in people with diabetes and minimal or
no diabetic retinopathy. Am J Ophthalmol 2008
May145(5)894-901