Long‐term repeatability of optical coherence tomography angiography parameters in healthy eyes

Abstract

Purpose: To determine the long-term repeatability of optical coherence tomography angiography (OCTA) parameters in normal eyes. Methods: We prospectively enrolled 104 normal eyes. Participants were divided into three groups based on differences in the signal strength (SS) of OCTA scans obtained at two visits at least 6 months apart: group 1, SS difference = 2; group 2, 1; group 3, 0. We measured a foveal centred scan area of 3 3 3 mm pattern. All measurements were performed twice at 5-min intervals at the initial visit. The second measurements were performed at least 6 months later. Results: In short-term vessel density (VD) repeatability, the coefficient of variation (CV) ranged from 3.89% to 8.10% and the intraclass correlation coefficient (ICC) ranged from 0.785 to 0.941. In terms of long-term repeatability, the CV was 5.39-12.62% and the ICC was 0.598-0.867. In group 1, the ICCs of the inner and full VDs were 0.194 and 0.221, respectively. In groups 2 and 3, the ICCs of the inner and full VDs were 0.611 and 0.603, and 0.763 and 0.765, respectively. The central VDs of all groups had high CV besides high ICC.Conclusions: Optical coherence tomography angiography parameters showed good short-term and reasonable long-term repeatability in normal individuals. The differences in SSs between measurements affected such repeatability, so physicians should query the reliability of OCTA parameters when the differences in SS are 2 or more even when the SS is high.

Comparison of foveal avascular zone and retinal vascular density in healthy Chinese and Caucasian adults

“…The short‐term coefficient of variation ranged from 3.89% to 8.10% while long‐term ranged from 5.39% to 12.62% (Lee et al. ).…”

Long-term repeatability of peripapillary optical coherence tomography angiography measurements in healthy eyes

“…Lee et al 14 reported that the SS had a significant positive association with the long-term repeatability of OCTA parameter measurements. However, in our previous long-term macular OCTA study, only the differences in SS between two measurements were significant in the multivariate analysis, not the mean SS 13 . This difference in results is probably due to the recruitment of eyes with lower SS (SS ≥ 7).…”

“…Previously, many studies have reported good short-term repeatability of OCTA (including peripapillary OCTA) measurements in people with normal and diseased eyes 10 – 12 . In long-term repeatability, previous our study found that macula OCTA had reasonable repeatability in healthy eyes 13 . Furthermore, Lee et al 14 reported good long-term reproducibility of peripapillary OCTA measurements in patients with suspicion of glaucoma.…”

“…Although this study did not include healthy eyes, the results are similar to ours. In healthy eyes study, our previous study with macular OCTA parameters, using a SS > 7 and a 3 × 3 mm area scan, found that OCTA had reasonable long-term repeatability in healthy eyes (CV: 5.39–12.62%) 13 . However, in a clinical setting, peripapillary OCTA sometimes requires a manual control more than macular, such as the gaze position in examination and disc centering when analyzing the results.…”

Albuminuria and retinal vessel density in diabetes without diabetic retinopathy: the Kailuan Eye Study

“…We assessed the VD and PD separately in the superficial capillary plexus in the foveal area, the parafoveal sectors and the whole macular region. Previous studies have shown a good repeatability of the measurements of the macular vascular and foveal avascular zone parameters in normal individuals (Lee et al 2020) and in patients with ocular disorders (Li et al 2018; Kim et al 2020). Using the enhanced depth imaging mode of the OCT and the in‐built software (Cirrus 5000 AngioPlex Metrix version 10.0), we measured the subfoveal choroidal thickness.…”