Deep Capillary Plexus Parameters Determine Diabetic Retinopathy Severity

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Ophtalmological practice, Geneva, Switzerland, Carrying out OCT angiography to detect the presence of neovascularisation, angiography with autofluorescence and optical coherence tomography. (Photo by: BSIP/Universal Images Group via Getty Images)
Deep capillary plexus geometric perfusion deficits had the largest area under the operator receiving characteristic curves for detecting clinically referable eyes, the report states.

Deep capillary plexus (DCP) vascular parameters can detect clinically referrable eyes with diabetic retinopathy (DR) through optical coherence tomography angiography (OCT-A), according to research published in Ophthalmology Retina. 

Researchers conducted a retrospective, cross-sectional study of 150 eyes of 150 patients with diabetes mellitus (DM) to determine the sensitivity (SN) and specificity (SP) of OCT-A parameters for discriminating clinically referrable eyes with DR. They defined “clinically referrable” as having moderate DR or worse or diabetic macular edema. The team measured vessel density, vessel density length (VDL), retinal geometric perfusion deficits (GPD), GDP including the foveal avascular zone (GDP𝑓), superficial capillary plexus (SCP), and deep capillary plexus (DCP) using OCT-A imaging. Area under the receiver operating characteristic curve (AUC), SN, and SP determined the usefulness of each parameter for determining clinically referrable status. 

Investigators determined that 71 patients had clinically referrable DR. They noted that GDP𝑓 performed better than GDP in detecting clinically referrable DR in the SCP (P =.025), according to the report. In the DCP, GPD was the best metric for identifying clinically referrable eyes (AUC=.965, SN=97.2%, SP=84.8%). GPD and GPD𝑓 had a larger AUC than the vessel density for the full retina, SCP and DCP. However, these values only achieved clinical significance in the full retinal thickness layers (P <.05) and DCP GPD (P =.017).

“OCT-A can distinguish eyes with referrable DR,” according to the researchers. “We believe it has a role as an adjunct to conventional imaging methods for detecting referrable DR. Capitalizing on the many advantages of this technology, developing a color-coded map of perfusion deficits, using cross-sectional OCT data for assessing DME, and longitudinal follow-up metrics can provide great clinical value for evaluating DR and DMI.”

Study limitations include its retrospective nature and a limited number of eyes with moderate and severe nonproliferative DR


Nesper PL, Ong JX, Fawzi AA. Deep capillary geometric perfusion deficits on OCT angiography detect clinically referrable eyes with diabetic retinopathy. Ophthalmol Retina. Published online June 2, 2022. doi:10.1016/j.oret.2022.05.028