Comparison of optical coherence tomography assessments in the comparison of age-related macular degeneration treatments trials

Ophthalmology. 2014 Oct;121(10):1956-65. doi: 10.1016/j.ophtha.2014.04.020. Epub 2014 May 15.

Abstract

Objective: To determine agreement between spectral-domain (SD) and time-domain (TD) optical coherence tomography (OCT) image assessments by certified readers in eyes treated for neovascular age-related macular degeneration (AMD).

Design: Cross-sectional study within the Comparison of AMD Treatments Trials (CATT).

Participants: During year 2 of CATT, 1213 pairs of SD OCT and TD OCT scans were compared from a subset of 384 eyes.

Methods: Masked readers independently graded OCT scans for presence of intraretinal fluid (IRF), subretinal fluid (SRF), and sub-retinal pigment epithelium (RPE) fluid and performed manual measurements of retinal, SRF, and subretinal tissue complex thicknesses at the foveal center.

Main outcome measures: Presence of fluid was evaluated with percent agreement, κ coefficients with 95% confidence intervals (CIs), and McNemar tests. Thickness measurements were evaluated with mean difference (Δ) ±95% limits of agreement and intraclass correlation coefficients (ICCs) with 95% CIs.

Results: Between SD OCT and TD OCT, agreement on presence of any fluid was 82% (κ = 0.46; 95% CI, 0.40-0.52), with 5% more SD OCT scans demonstrating fluid (P<0.001). Agreement on presence of SRF was 87% and sub-RPE fluid was 80%, with more SD OCT scans demonstrating fluid (both P < 0.001). Agreement on IRF was 73% (κ = 0.47; 95% CI, 0.42-0.52), with 6% more TD OCT scans demonstrating fluid (P < 0.001). Between SD OCT and TD OCT, mean thickness of the retina was Δ = 5±67 μm, SRF was Δ = 1.5±35 μm, and subretinal tissue complex was Δ = 5±86 μm. Thickness measurements were reproducible for retina (ICC = 0.84; 95% CI, 0.83-0.86), SRF (ICC = 0.88; 95% CI, 0.86-0.89), and subretinal tissue complex (ICC = 0.91; 95% CI, 0.89-0.92), with ≤25-μm difference in these measurements in 71%, 94%, and 61% of paired scans, respectively.

Conclusions: Agreement on fluid presence and manual thickness measurements between paired scans from each OCT modality was moderate, providing a reasonable basis to compare CATT results with future SD OCT-based trials. Fluid was detected 5% more frequently with SD OCT, which may increase frequency of fluid-based treatment. Lower-resolution and artifactual interpretation of dark areas as cystoid edema may explain the greater frequency of IRF detected with TD OCT.

Trial registration: ClinicalTrials.gov NCT00593450.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Angiogenesis Inhibitors / therapeutic use
  • Antibodies, Monoclonal, Humanized / therapeutic use
  • Bevacizumab
  • Cross-Sectional Studies
  • Humans
  • Macular Degeneration / diagnosis*
  • Macular Degeneration / drug therapy
  • Prospective Studies
  • Ranibizumab
  • Reproducibility of Results
  • Tomography, Optical Coherence / methods*
  • Tomography, Optical Coherence / standards

Substances

  • Angiogenesis Inhibitors
  • Antibodies, Monoclonal, Humanized
  • Bevacizumab
  • Ranibizumab

Associated data

  • ClinicalTrials.gov/NCT00593450