In this literature review article, based on scientific research published over the past 5 years, the significance of morphometric and microvascular indicators of the fundus in the early diagnosis of non-proliferative diabetic retinopathy (NPDR) was studied. In particular, such parameters as choroidal vascularity index (CVI), choriocapillary flow rate, retinal vascular density, and foveal avascular zone (FAZ) were assessed as diagnostic biomarkers.

Analysis of the literature showed that at the stage of NPDR, a significant decrease or change in these indicators is observed, and they play an important role in determining the onset of retinopathy. Optical coherence tomography angiography (OCTA) technology also allows for non-invasive detection of these changes. CVI and chorocapillary flow are distinguished as the most sensitive biomarkers, while choroidal thickness is considered only as an auxiliary parameter. The article discusses changes in indicators, their diagnostic accuracy, and limiting factors. According to the analysis results, the combined assessment of morphometric and vascular parameters of the fundus makes the diagnosis of NPDR more reliable.

diabetic retinopathy, nonproliferative stage, choroidal vascularity index, choriocapillaris, FAZ, optical coherence tomography, OCTA, morphometry, early diagnosis.

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