Article

Reproducibility of Spectral-Domain Optical Coherence Tomography Total Retinal Thickness Measurements in Mice

UPMC Eye Center, Eye and Ear Institute, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
Investigative ophthalmology & visual science (Impact Factor: 3.66). 12/2010; 51(12):6519-23. DOI: 10.1167/iovs.10-5662
Source: PubMed

ABSTRACT To test the reproducibility of spectral-domain optical coherence tomography (SD-OCT) total retinal thickness (TRT) measurements in mice.
C57Bl/6 mice were anesthetized, and three repeated volumetric images were acquired in both eyes with SD-OCT (250 A-scans × 250 frames × 1024 samplings), centered on the optic nerve head (ONH). The mice were repositioned between scans. TRT was automatically measured within a sampling band of retinal thickness with radii of 55 to 70 pixels, centered on the ONH by using custom segmentation software. The first volumetric image acquired in a given eye was used to register the remaining two SD-OCT images by manually aligning the en face images with respect to rotation and linear translation. Linear mixed-effects models were fitted to global and quadrant thicknesses, taking into account the clustering between eyes, to assess imprecision (measurement reproducibility).
Twenty-six eyes of 13 adult mice (age 13 weeks) were imaged. The mean global TRT across all eyes was 298.21 μm, with a mouse heterogeneity standard deviation (SD) of 4.88 μm (coefficient of variation [CV] = 0.016), an eye SD of 3.32 μm (CV = 0.011), and a device-related imprecision SD of 2.33 μm (CV = 0.008). The superior quadrant had the thickest mean TRT measurement (310.38 μm) and the highest (worst) imprecision SD (3.13 μm; CV = 0.010), and the inferior quadrant had the thinnest mean TRT (291.55 μm). The quadrant with the lowest (best) imprecision SD was in the nasal one (2.06 μm; CV = 0.007).
Good reproducibility was observed for SD-OCT retinal thickness measurements in mice. SD-OCT may be useful for in vivo longitudinal studies in mice.

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