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Updated: Mar 11, 2026
07:11
Assessing Early Stage Open-Angle Glaucoma in Patients by Isolated-Check Visual Evoked Potential
Published on: May 25, 2020
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Inter-visit Test-Retest Variability of OCT in Glaucoma.
John Graham Pearce1, Ted Maddess
1*MOptom †PhD Eccles Institute for Neuroscience, John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia (all authors).
Summary
Test-retest variability of the Topcon 3D OCT-2000 in glaucoma patients showed excellent repeatability for ganglion cell complex (GCC) measurements. Peripapillary retinal nerve fiber layer (pRNFL) variability increased with glaucomatous damage.
Area of Science:
- Ophthalmology
- Medical Imaging
- Glaucoma Research
Background:
- Glaucoma management relies on accurate and repeatable ocular measurements.
- Spectral domain optical coherence tomography (SD-OCT) is crucial for monitoring glaucoma progression.
- Understanding test-retest variability (TRV) is essential for detecting true changes.
Purpose of the Study:
- To assess the inter-visit TRV of the Topcon 3D OCT-2000 for optic nerve head (ONH) topography, peripapillary retinal nerve fiber layer (pRNFL), and macular ganglion cell complex (GCC) parameters.
- To investigate if TRV differs based on the severity of glaucomatous damage.
Main Methods:
- Twenty-four glaucoma patients with varying disease severity were included.
- SD-OCT scans (3D Disc Retinal Nerve Fiber Layer Analysis and Macula V) were repeated one week apart.
- Inter-visit TRV was calculated using Bland-Altman limits of agreement (LoA) and coefficients of repeatability (CR).
Main Results:
- Excellent repeatability was observed for GCC measurements (CR = 2.9 μm).
- Horizontal and vertical cup/disc ratio CRs were low (0.05 and 0.07).
- Peripapillary retinal nerve fiber layer (pRNFL) TRV increased with greater glaucomatous damage, described by a specific formula.
Conclusions:
- The Topcon 3D OCT-2000 demonstrates excellent repeatability for GCC measurements in glaucoma patients.
- When assessing pRNFL thickness, clinicians must consider the average pRNFL thickness to determine statistically significant changes.
- TRV of pRNFL measurements is influenced by the extent of glaucomatous damage.
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