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Updated: Jun 11, 2026
Retinal Vascular Reactivity as Assessed by Optical Coherence Tomography Angiography
Published on: March 26, 2020
Repeatability of choroidal optical coherence tomography angiography metrics in healthy young adults
Azam Darvishi1, Scott A Read1, Stephen J Vincent1
1Contact Lens and Visual Optics Laboratory, Centre for Vision and Eye Research, School of Optometry and Vision Science, Queensland University of Technology, Brisbane, Australia.
Clinical Relevance:
Assessment of choroidal perfusion plays an important role in evaluating ocular vascular status and may assist in managing vascular alterations in ocular and systemic disease.
Background:
Optical coherence tomography (OCT) angiography enables non-invasive assessment of choroidal perfusion; however, repeatability across different depths remains unclear. This study evaluated within- and between-day repeatability of choroidal OCT angiography measurements in healthy young adults and the effect of image pre-processing.
Methods:
Twenty healthy adults (18-35 years) underwent repeated imaging using Heidelberg Spectralis OCT angiography. Perfusion density was quantified in choriocapillaris and three custom slabs representing superficial, intermediate, and deep choroid. The standard (device-defined) choroidal slab was also analysed. Within-day repeatability used scans acquired 60 minutes apart, and between-day repeatability scans from different days at the same time. The influence of image pre-processing was assessed.
Results:
Perfusion density differed significantly across layers, increasing from superficial to deep (p < 0.001), while the choriocapillaris did not differ from superficial or intermediate layers, it was lower than the deep choroid (p = 0.014). A significant regional effect was observed, with higher perfusion density in the central (1 mm) than inferior (2 mm) region (p = 0.009). Within-day repeatability was excellent (intraclass correlation coefficients > 0.90), with standard choroid showing highest stability. Between-day repeatability was good (intraclass correlation coefficients = 0.77-0.91), with the greater variability in deeper layers. Variability was lower in the 2 mm parafoveal zone compared to the 1 mm foveal zone in the standard and deep choroid (both p < 0.05). Image pre-processing significantly improved between-day repeatability for standard choroid (p < 0.05).
Conclusion:
Choroidal perfusion metrics showed excellent within-day and good between-day repeatability, with systematic differences across layers and regions. Image pre-processing improved measurement precision, supporting OCT angiography as a reliable tool for clinical and research assessment of the choroid.
