Optical coherence tomography angiography analysis of foveal microvascular changes and inner retinal layer thinning in patients with diabetes.

To evaluate the correlation between inner retinal layer thinning and the foveal microvasculature in type 2 diabetes using optical coherence tomography angiography (OCTA). A cross-sectional study involved 155 diabetic eyes. All patients were divided into two groups based on diabetic retinopathy (DR) grade: no DR (NDR, n=80) and mild-to-moderate non-proliferative DR (NPDR, n=75). Foveal avascular zone (FAZ) area, FAZ circularity index, FAZ perimeter, vessel density and perfusion index of parafoveal and perifoveal area were calculated using OCTA. The thickness of the macular ganglion cell/inner plexiform layer (mGCIPL) was measured using OCT. In both superficial and deep retinal capillary layers (SRL and DRL), FAZ areas in the NDR (0.38 mm2 , 0.49 mm2) and NPDR (0.38 mm2, 0.48 mm2) were greater than those in the control (0.33 mm2, 0.43 mm2). The FAZ circularity index, vessel density and perfusion index in the NDR (0.63, 17.8/mm, 0.32) and NPDR (0.63, 17.5/mm, 0.32) were smaller than those in the control (0.69, 19.6/mm, 0.39). mGCIPL thickness was significantly correlated with FAZ area in the SRL and DRL, as well as with FAZ circularity index, vessel density and perfusion index in the NDR and NPDR. In multivariate regression analysis, the FAZ circularity index (OR=12.2) and vessel density of the parafovea (OR=1.95) were correlated with mGCIPL thinning. OCTA revealed that early foveal microcirculatory alterations in diabetic eyes were related to mGCIPL thickness, regardless of the presence of DR. The decrease in FAZ circularity and parafoveal vessel density were highly correlated with mGCIPL thinning.

Kim K ，Kim ES ，Yu SY 《-》

Progressive retinal neurodegeneration and microvascular change in diabetic retinopathy: longitudinal study using OCT angiography.

Kim K ，Kim ES ，Kim DG ，Yu SY ... -  《-》

Evaluation of Foveal and Parafoveal Microvascular Changes Using Optical Coherence Tomography Angiography in Type 2 Diabetes Patients without Clinical Diabetic Retinopathy in South Korea.

The aim of this study was to investigate foveal and parafoveal microvascular changes in retinal vascular plexuses in patients with type 2 diabetes mellitus (DM) without clinical diabetic retinopathy (NDR) using optical coherence tomography angiography (OCTA) in South Korea. We included 64 patients in the NDR group and included 48 healthy control subjects for comparison. All subjects underwent ocular examination with visual acuity and wide-field fundus photos. Foveal and parafoveal vessel density and foveal avascular zone (FAZ) area (mm2) in the superficial capillary plexus (SCP) and deep capillary plexus (DCP) were analyzed. Foveal vessel densities in both the SCP and DCP were decreased in the NDR group compared to the controls (p = 0.034 and 0.001, respectively). Vessel densities in the superior and inferior parafoveae in the DCP were decreased in the NDR group compared to the controls (p = 0.006 and 0.034, respectively). The FAZs of the SCP and DCP were significantly different between the NDR group and the controls (p = 0.003 and 0.001, respectively). The average vessel densities of the SCP and DCP were not correlated with HbA1c, serum creatinine, or the duration of DM in the NDR group. We demonstrated that OCTA can identify early-stage DR before the manifestation of clinically apparent retinopathy in diabetic eyes. Diabetic patients without clinical DR have microvascular alterations (foveal vessel density, parts of the parafovea, and enlarged FAZ) in the SCP and DCP. Our results suggest that OCTA might be a promising tool for early detection of eyes with DR.

Park YG ，Kim M ，Roh YJ 《-》

QUANTIFICATION OF RETINAL VESSEL TORTUOSITY IN DIABETIC RETINOPATHY USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

Lee H ，Lee M ，Chung H ，Kim HC ... -  《-》

Macular vessels density in diabetic retinopathy: quantitative assessment using optical coherence tomography angiography.

AttaAllah HR ，Mohamed AAM ，Ali MA 《-》