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Updated: Oct 13, 2025
Optical Coherence Tomography: Imaging Mouse Retinal Ganglion Cells In Vivo
Published on: September 22, 2017
Ganglion cell-inner plexiform layer measurements derived from widefield compared to montaged 9-field optical
Janelle Tong1,2, Nayuta Yoshioka1, David Alonso-Caneiro3
1School of Optometry and Vision Science, University of New South Wales (UNSW), Sydney, Australia.
Clinical Relevance:
With equivalent inner retinal thickness measurements compared to a more conventional composite optical coherence tomography (OCT) protocol, Widefield optical coherence tomography (WF-OCT) is a clinically viable, time-saving option facilitating detection of ocular pathologies within the central 55° of the retina.
Purpose:
To compare ganglion cell-inner plexiform layer (GCIPL) thicknesses obtained using a single WF-OCT scan and standard composite OCT scans acquired in 9 fields of gaze (9F-OCT).
Methods:
Thirteen healthy participants underwent WF-OCT and 9F-OCT using the Spectralis OCT. The GCIPL was automatically segmented with a manual review for 9F-OCT and was manually segmented for WF-OCT. After registration, differences in GCIPL thicknesses were compared using 95% confidence intervals computed from one-sample t-tests and Bland-Altman analyses. Location-specific differences in B-scan tilt were analysed using Spearman correlations and linear regression models. To determine whether B-scan tilt influences GCIPL measurements, regression models of tilt versus differences between perpendicular and axial GCIPL thickness were applied.
Results:
While scattered locations demonstrated significant GCIPL thickness differences between WF-OCT and 9F-OCT, most differences did not exceed the axial pixel resolution of the instrument of 3.87 µm. Bland-Altman analyses indicated no notable bias using WF-OCT. Moderate correlations indicating significant location-specific differences in B-scan tilt were observed for temporal, central and inferior B-scans (r = -0.62 to 0.72), with linear regression models predicting a maximum difference in the tilt of 4.65°. The quadratic regression model indicated that at tilts greater than 27.3°, perpendicular GCIPL measurements become increasingly thin relative to axial measurements.
Conclusions:
GCIPL thicknesses and B-scan tilts from WF-OCT are comparable to 9F-OCT, indicating that WF-OCT can be applied clinically to obtain valid inner retinal OCT measurements over 55° of the central retina with relative ease. However, for peripheral locations, B-scan tilt may need to be considered when measuring GCIPL thicknesses.
