Contrast Sensitivity Better Differentiates Wide-Field Swept-Source Optical Coherence Tomography Angiography Vascular Metrics Among Healthy Eyes Compared to Visual Acuity

Abstract

Purpose : This study aimed to evaluate the associations between wide-field swept-source optical coherence tomography angiography (WF SS-OCTA) metrics with visual acuity (VA) and contrast sensitivity (CS) among healthy eyes.

Methods : This cross-sectional study has 57 eyes of 45 patients from May 2019 to April 2022 who had same day VA, CS, and OCTA. Median age was 61 (52 - 65) years. Median logMAR VA was 0 (0 - 0). Eyes were imaged with WF SS-OCTA (PLEX Elite 9000, Carl Zeiss Meditec) and tested with Quantitative CS function (qCSF, Adaptive Sensory Technology). Functional outcomes included Snellen VA, and the CS metrics: Area under the Log CSF (AULCSF), contrast acuity (CA), and contrast sensitivity (CS) thresholds at 1 to 18 cycles per degree (cpd). The ARI Network (Zeiss Portal v5.4) quantified vessel density (VD) and vessel skeletonized density (VSD) in the superficial (SCP) and deep (DCP) capillary plexus and whole retina (WR), and foveal avascular zone (FAZ) area, circularity, and perimeter on 3, 6, and 12 mmxmm OCTA images. Mixed effects multivariable regression analyses were performed (p<0.05) using backward stepwise elimination.

Results : Multivariable regression results, controlling for age, lens status, and laterality, revealed that VA was significantly associated with FAZ area (β = -0.35, p = 0.040) and perimeter (β = -0.07, p = 0.022) on 3mmxmm scans but did not have significant associations with vascular metrics on 6 and 12 mmxmm images. Multiple CS metrics were significantly associated with OCTA vascular metrics on all three image sizes. For example, VD and VSD in the DCP on 12 mmxmm images was significantly associated with AULCSF (β = 0.82, p = 0.036; β = 0.02, p = 0.028, respectively) and CS at 6 cpd (β = 0.97, p = 0.040; β = 0.03, p = 0.032), 12 cpd (β = 1.36, p = 0.011; β = 0.04, p = 0.008), and 18 cpd (β = 1.17, p = 0.007; β = 0.03, p = 0.006).

Conclusions : Our results revealed significant associations between CS and WF SS-OCTA among healthy eyes, suggesting that CS is a sensitive visual function metric that likely reflects retinal microvasculature differences not detected by Snellen VA. Using CS in routine clinical practice may help screening for retinal diseases, particularly given the rising myopia epidemic and aging population, and improve understanding of how retinal microvasculature influences visual function.

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