Quantifying vascular density and morphology using different swept-source optical coherence tomography angiographic...

Area of Science:

• Ophthalmology
• Medical Imaging
• Diabetology

Background:

• Diabetic retinopathy (DR) is a leading cause of vision loss.
• Early detection and monitoring of DR are crucial for effective management.
• Quantitative analysis of retinal microvasculature aids in assessing DR severity.

Purpose of the Study:

• To evaluate quantitative metrics of the retinal microvasculature in diabetic retinopathy (DR).
• To assess the utility of various en face swept-source optical coherence tomography angiography (SS-OCTA) image sizes for DR detection.
• To compare different quantitative parameters (perfusion density, vessel length density, fractal dimension) across various scan sizes.

Main Methods:

• Acquisition of non-segmented and segmented SS-OCTA images using a PLEX Elite 9000 device.
• Utilized scanning fields of view: 3x3 mm, 6x6 mm, and 12x12 mm.
• Performed quantitative analysis of perfusion density (PD), vessel length density (VLD), and fractal dimension (FD); assessed DR prediction ability using receiver operating characteristic curves.

Main Results:

• Quantitative parameters (PD, VLD, FD) progressively decreased with increasing DR severity across all SS-OCTA scan sizes.
• Significantly lower PD and FD were observed in patients with non-proliferative DR (NPDR) and proliferative DR (PDR) compared to healthy individuals.
• The 3x3 mm SS-OCTA images demonstrated the best predictive ability for DR detection across all evaluated quantitative parameters.

Conclusions:

• Quantitative evaluations combining different SS-OCTA scan sizes and parameters provide detailed monitoring of vascular changes in DR.
• Smaller scan sizes, particularly 3x3 mm, are highly effective for detecting and predicting diabetic retinopathy.
• SS-OCTA offers a valuable tool for the comprehensive assessment of DR progression.