Within-visit and between-visit variability of optical coherence tomography and optical coherence tomography angiography measurements in healthy eyes

Abstract

Purpose : To evaluate the repeatability and reproducibility of optical coherence tomography (OCT) and OCT angiography measurements of glaucoma diagnostic parameters.

Methods : Healthy eyes were scanned with optic disc scan (6 × 6 mm) and macular scan (6.4 × 6.4 mm) using Solix spectral-domain OCT (V1.0.0.342, Visionix/Optovue, CA). For each scan pattern, two consecutive scans were obtained at a baseline visit and at a follow-up visit 2 weeks later. To ensure scan quality, all scans had signal strength index (SSI) above the acceptance cutoff of 50. Peripapillary nerve fiber layer (NFL) thickness, peripapillary NFL Plexus capillary density (NFLP-CD), macular ganglion cell complex (GCC) thickness and macular superficial vascular complex vessel density (SVC VD) were evaluated for within-visit repeatability and between-visit reproducibility. Pooled standard deviation (SD) and coefficient of variation (CV) were used to evaluate repeatability and reproducibility.

Results : In total, 22 healthy eyes of 22 individuals with age 34 ± 8 (mean ± SD) years were prospectively enrolled. For optic disc and macular scans average SSI were 74.5 ± 8.4 and 77.0 ± 6.5, respectively. The reproducibility and repeatability of measurements was excellent for structural OCT and OCT angiography (Table 1). The population variability of OCT angiography parameters shows narrower range than structural OCT.

Conclusions : The Solix instrument has good reproducibility and repeatability for both OCT and OCT angiography measurements in the peripapillary and macular regions, showing good potential for monitoring glaucoma. The narrow normative range of OCT angiography parameters may be advantageous for disease diagnosis.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.

 

Table 1. Variability of OCT & OCT Angiography Measurements