Spatial distribution of diabetic capillary non-perfusion

Area of Science:

• Ophthalmology
• Retinal Imaging
• Diabetic Retinopathy Research

Background:

• Diabetic retinopathy (DR) is a leading cause of vision loss.
• Understanding the patterns of retinal ischemia is crucial for managing DR.
• Capillary non-perfusion (CNP) is a key feature of DR, affecting different retinal layers.

Purpose of the Study:

• To investigate the distribution of capillary non-perfusion (CNP) in the superficial and deep capillary plexuses (SCP and DCP) in eyes with diabetic retinopathy (DR).
• To analyze the spatial correlation and extent of CNP in different retinal layers.
• To correlate CNP with visual acuity in DR patients.

Main Methods:

• Retrospective analysis of macular optical coherence tomography angiography (OCTA) images from DR eyes without diabetic macular edema (DME).
• Automated delineation of CNP areas in SCP and DCP, excluding the foveal avascular zone and major vessels.
• Statistical analysis of CNP distribution, spatial correlation, and association with best-corrected visual acuity (BCVA).

Main Results:

• Eyes with DR showed significantly higher CNP in SCP compared to DCP (0.722 mm² vs. 0.184 mm²).
• A significant association was found between BCVA and CNP area in the DCP (p = .01).
• CNP distribution varied significantly across concentric rings, decreasing towards the foveal center in both plexuses.

Conclusions:

• Superficial capillary plexus (SCP) exhibits more ischemia than the deep capillary plexus (DCP) in diabetic retinopathy (DR).
• This contrasts with findings in acute retinal vascular occlusions, suggesting a different ischemic mechanism in DR.
• The study enhances understanding of retinal ischemia in the context of diabetic retinopathy.