Structure-function associations between contrast sensitivity and widefield swept-source optical coherence tomography...

Area of Science:

• Ophthalmology
• Medical Imaging
• Diabetology

Background:

• Diabetic macular edema (DME) is a leading cause of vision loss in diabetic patients.
• Contrast sensitivity (CS) and visual acuity (VA) are key measures of visual function.
• Widefield swept-source optical coherence tomography angiography (WF SS-OCTA) provides detailed vascular imaging.

Purpose of the Study:

• To investigate the relationship between contrast sensitivity (CS) and WF SS-OCTA-derived vascular metrics in patients with DME.
• To compare the association of vascular changes with CS versus VA in DME.

Main Methods:

• A cross-sectional study of 61 eyes from 48 patients with DME.
• Quantitative contrast sensitivity (qCSF) testing and WF SS-OCTA imaging were performed.
• Vascular metrics (vessel density, vessel skeletonized density) and foveal avascular zone parameters were analyzed.
• Statistical models controlled for age, lens status, and diabetic retinopathy stage.

Main Results:

• WF SS-OCTA metrics showed significant associations with both CS and VA.
• The impact of OCTA metrics on CS was greater than on VA, particularly at 3 cycles per degree.
• CS metrics, including AULCSF, were significantly associated with vessel density and skeletonized density across all retinal layers, whereas VA was not.

Conclusions:

• Microvascular alterations in DME, as visualized by WF SS-OCTA, correlate more strongly with reduced contrast sensitivity than with visual acuity.
• Contrast sensitivity may serve as a more sensitive functional marker for microvascular changes in DME compared to traditional visual acuity testing.