Macular Capillary Perfusion in Chinese Patients With Diabetic Retinopathy Obtained With Optical Coherence Tomography Angiography.

To compare the macular perfusion in the retina and choroidal layer between control subjects and Chinese patients with diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA) and to evaluate the association of OCTA characteristics with the stage of DR. A total of 200 eyes (normal controls = 40; mild non-proliferative diabetic retinopathy [NPDR] = 40; moderate NPDR = 40; severe NPDR = 40; and PDR [proliferative diabetic retinopathy] = 40) underwent OCTA imaging. OCTA parameters were vessel densities in the superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris, as well as foveal avascular zone (FAZ) area (mm2) in the SCP. The reduction of macular perfusion in the SCP, DCP, and choriocapillaris was correlated with increasing severity of DR. Vessel density in the SCP, DCP, and choriocapillaris was 55.31% ± 2.56%, 62.40% ± 2.46%, and 66.87% ± 1.30%, respectively, in control subjects; 50.58% ± 3.14%, 56.31% ± 4.24%, and 66.20% ± 1.69%, respectively, in mild NPDR; 46.46% ± 3.09%, 49.40% ± 5.68%, and 64.39% ± 1.94%, respectively, in moderate NPDR; 45.61% ± 3.81%, 49.33% ± 6.14%, and 63.75% ± 2.21%, respectively, in severe NPDR; and 43.78% ± 3.71%, 44.78% ± 6.36%, and 61.32% ± 6.29%, respectively, in PDR. Vessel density in DR groups decreased compared with normal controls (P < .001). FAZ area in the SCP was 0.34 ± 0.09 mm2 in control subjects compared with 0.48 ± 0.17 mm2 (mild NPDR), 0.52 ± 0.13 mm2 (moderate NPDR), 0.62 ± 0.24 mm2 (severe NPDR), and 0.75 ± 0.30 mm2 (PDR). FAZ in the SCP of patients with DR was greater than that in control subjects (P < .001). Vessel density in the DCP shows better ability to identify the severity of DR (area under the curve, sensitivity, and specificity of 0.967, 92.5%, and 93.1%, respectively) than vessel density in the SCP and choriocapillaris. OCTA might be clinically useful to evaluate different stages of DR in a noninvasive manner. Vessel density in DCP could be an objective and reliable indicator for monitoring progression of DR. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:e88-e95.].

Yang D ，Cao D ，Huang Z ，Xie J ，Meng Q ，Dong X ，Hu Y ，Zeng Y ，Zhang L ... -  《-》

Interaction Between the Distribution of Diabetic Retinopathy Lesions and the Association of Optical Coherence Tomography Angiography Scans With Diabetic Retinopathy Severity.

Ashraf M ，Sampani K ，Rageh A ，Silva PS ，Aiello LP ，Sun JK ... -  《-》

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

AttaAllah HR ，Mohamed AAM ，Ali MA 《-》

Deep Capillary Geometric Perfusion Deficits on OCT Angiography Detect Clinically Referable Eyes with Diabetic Retinopathy.

To evaluate the sensitivity (SN) and specificity (SP) of OCT angiography (OCTA) parameters for detecting clinically referable eyes with diabetic retinopathy (DR) in a cohort of patients with diabetes mellitus (DM). Retrospective, cross-sectional study. Patients with DM with various levels of DR. We measured vessel density, vessel length density (VLD), and geometric perfusion deficits (GPDs) in the full retina, superficial capillary plexus (SCP), and deep capillary plexus (DCP) on 3 × 3-mm OCTA images. Geometric perfusion deficit was recently described as retinal tissue located further than 30 μm from blood vessels, excluding the foveal avascular zone (FAZ). We modified the GPD metric by including the FAZ as an additional variable. Clinically referable eyes were defined as moderate nonproliferative DR (NPDR) or worse retinopathy, or diabetic macular edema (DME). One eye from each patient was selected for the analysis based on image quality. We used a binary logistic regression model to adjust for covariates. Sensitivity, SP, and area under the curve (AUC). Seventy-one of 150 included eyes from 150 patients (52 with DM without DR, 27 with mild NPDR, 16 with moderate NPDR, 10 with severe NPDR, 30 with proliferative DR, and 15 with DME) had clinically referable DR. Geometric perfusion deficit metric that included the FAZ performed better than GPD in detecting referable DR in the SCP (P = 0.025) but not the DCP or full retina (P > 0.05 for both). Deep capillary plexus GPD had the largest AUC for detecting clinically referable eyes (AUC = 0.965, SN = 97.2%, SP = 84.8%), which was significantly larger than the AUC for vessel density of any layer (P < 0.05 for all) but not DCP VLD (P = 0.166). The cutoff value of 2.5% for DCP GPD resulted in a highly sensitive test for detecting clinically referable eyes without adjusting for covariates (AUC = 0.955, SN = 97.2%, SP = 79.7%). Vascular parameters in OCTA, especially in the DCP, have the potential to identify eyes that warrant further evaluation. Geometric perfusion deficits may better distinguish these clinically referable eyes with DR than standard vessel density parameters.

Nesper PL ，Ong JX ，Fawzi AA 《-》

Changes of blood flow in macular zone of patients with diabetic retinopathy at different stages evaluated by optical coherence tomography angiography.

To evaluate changes in macular blood flow in patients with various stages of diabetic retinopathy (DR) by optical coherence tomography angiography (OCTA). The data of 94 patients (122 eyes) with type 2 diabetes mellitus admitted from January 2018 to May 2021 were recorded, including 31 patients (42 eyes) with no DR (NDR group), 33 patients (40 eyes) with mild non-proliferative DR (mild NPDR group) and 30 patients (40 eyes) with moderate NPDR (moderate NPDR group). Forty healthy patients (40 eyes) who were examined during the same period were selected as control group. The blood flow densities at the superficial capillary plexus (SCP), deep capillary plexus (DCP) and 300μm-wide region near the foveal avascular zone (FAZ) (FD300), FAZ area, FAZ perimeter and acircularity index (AI) were compared. Correlations of blood flow densities at the SCP, DCP and FD300, FAZ area, FAZ perimeter and AI with the severity of DR were investigated by multivariate regression analysis. A receiver operating characteristic (ROC) curve was plotted to analyze the predictive efficacy of the OCTA indices for early DR. Blood flow densities at the SCP, DCP and FD300 significantly decreased, while FAZ perimeter and AI increased in the NDR and DR groups compared with those of the control group (P<0.05). Blood flow densities at the SCP, DCP and FD300 of the DR group were lower than those of the NDR group, but the FAZ perimeter and AI of the former were larger (P<0.05). Blood flow densities at the SCP, DCP and FD300 in the macular zone of DR patients declined with increasing DR stage, while FAZ perimeter and AI increased (P<0.05), without collinearity among the variables. The area under the curve of FD300 for predicting early DR was highest (0.804), with a sensitivity and specificity of 84.13% and 67.19%, respectively. AI with a cut-off value of 1.05 showed the optimal specificity (87.84%) and sensitivity (73.62%) for predicting early DR. The flow density at FD300 declines, while FAZ perimeter and AI increase in the macular zone of patients with early DR. These three OCTA indicators show close associations with DR stage, and can function as predictors of early DR.

Zhao S ，He J ，Qiu M ，Liang X ... -  《-》