Structure-Function Associations between Novel Contrast Sensitivity Function (CSF) Testing and Widefield Swept-Source Optical Coherence Tomography Angiography (WF SS-OCTA) in Diabetic Macular Edema (DME)

Abstract

Purpose : To elucidate the relationship between CSF and WF SS-OCTA metrics in patients with DME.

Methods : This cross-sectional prospectively recruited observational study included 53 eyes of 37 patients with DME imaged with WF SS-OCTA (PLEX® Elite 9000, Carl Zeiss Meditec) and tested for CSF with the Active Learning Quantitative CSF (qCSF) Manifold Contrast Vision Meter (Adaptive Sensory Technology) from November 2018 to March 2021. Functional outcomes included Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity (VA), and the following qCSF metrics: Area under the Log CSF (AULCSF), contrast acuity (CA), and contrast sensitivity thresholds at 1 to 18 cycles per degree (cpd). The ARI Network (Zeiss Portal v5.4) was used to quantify vessel density (VD) and vessel skeleton density (VSD) in the superficial (SCP) and deep (DCP) capillary plexus and whole retina, as well as foveal avascular zone (FAZ) area, circularity, and perimeter on 3x3 mm, 6x6 mm, and 12x12 mm OCTA images. Mixed effects multivariate regression analyses were performed.

Results : In our DME cohort, VA and contrast sensitivity (CS) outcomes were strongest associated with vascular metrics measured on 3x3 mm OCTA images compared to 6x6 mm and 12x12 mm images. While controlling for age and lens status, regression analyses revealed worse LogMAR VA was significantly associated with decreased SCP VD (β = -0.049, p = 0.026) and VSD (β = -2.562, p = 0.026) on 3x3 mm images. Among the CS outcomes, decreased AULCSF, CA, and CS thresholds at 1.5, 3, and 6 cpd were significantly associated with decreased SCP VSD (β = 3.533, p = 0.020; β = 2.826, p = 0.029; β = 2.629, p = 0.035; β = 3.590, p = 0.033; β = 4.672, p = 0.023, respectively). Decreased CS thresholds at 6 cpd was also significantly associated with SCP VD (β = 0.080, p = 0.043). While VA was not significantly associated with FAZ circularity, decreased CS thresholds at 1 and 1.5 cpd were significantly associated with decreased FAZ circularity (β = 0.567, p = 0.028; β = 0.669, p = 0.026, respectively).

Conclusions : We demonstrate novel structure-function associations in patients with DME leveraging a novel CSF device and WF SS-OCTA. Our results suggest that decreases in VD and VSD in the SCP of DME patients may be associated with larger changes in contrast sensitivity than in VA.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.