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 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 ... -  《-》

Choriocapillaris and retinal vascular plexus density of diabetic eyes using split-spectrum amplitude decorrelation spectral-domain optical coherence tomography angiography.

Split-spectrum amplitude decorrelation angiography for spectral-domain optical coherence tomography has enabled detailed, non-invasive assessment of vascular flow. This study evaluates choriocapillaris and retinal capillary perfusion density (CPD) in diabetic eyes using optical coherence tomography angiography (OCTA). Records of 136 eyes that underwent OCTA imaging at a single institution were reviewed. Eyes were grouped as non-diabetic controls (37 eyes), patients with diabetes mellitus (DM) without diabetic retinopathy (DM without DR, 31 eyes), non-proliferative diabetic retinopathy (NPDR, 41 eyes) and proliferative diabetic retinopathy (PDR, 27 eyes). Quantitative CPD analyses were performed on OCTA images for assessing perfusion density of the choriocapillaris and retinal plexus for all patients and compared between groups. Eyes with NPDR and PDR showed significantly decreased choriocapillaris CPD compared with controls, while DM eyes without DR did not show significant change. Choriocapillaris whole-image CPD was decreased by 8.3% in eyes with NPDR (p<0.01) and decreased by 7.1% in eyes with PDR (p<0.01). Choriocapillaris parafoveal CPD was decreased by 8.9% in eyes with NPDR (p<0.01) and decreased by 8.2% in eyes with PDR (p<0.01). Compared with controls, only eyes with PDR showed significantly decreased retinal CPD, as well as significantly increased foveal avascular zone (FAZ) area. In those patients, retinal whole-image CPD was decreased by 9.7% (p<0.01), retinal foveal CPD was decreased by 20.5% (p<0.01) and retinal parafoveal CPD was decreased by 11.4% (p<0.01). FAZ area was increased by 50.9% (p<0.01). Choriocapillaris and retinal CPD are reduced in diabetic retinopathy, while FAZ area is increased in eyes with PDR. Vascular changes captured by new imaging modalities can further characterise diabetic choroidopathy.

Conti FF ，Qin VL ，Rodrigues EB ，Sharma S ，Rachitskaya AV ，Ehlers JP ，Singh RP ... -  《-》

Retinal Vascular Caliber Association with Nonperfusion and Diabetic Retinopathy Severity Depends on Vascular Caliber Measurement Location.

To evaluate the association of retinal nonperfusion and diabetic retinopathy (DR) severity with location of vascular caliber measurement using ultrawide field (UWF) imaging. Retrospective image review. Adults with diabetes mellitus. All images from subjects with same-day UWF fluorescein angiography (FA) and color imaging were evaluated. Predominantly peripheral lesions (PPL) and DR severity were graded from UWF color images. Nonperfusion was quantified using UWF-FA in defined retinal regions [posterior pole (PP), mid-periphery (MP), far-periphery (FP)]. Retinal vessel calibers were measured at an optic disc centered inner and outer zone. Nonperfusion index (NPI) in the PP, MP and FP. Mean arteriole and venule diameter in the inner and outer zones. Two hundred eighty-five eyes of 193 patients (24.9% mild nonproliferative DR [NPDR], 22.8% moderate NPDR, 37.5% severe NPDR and 14.7% proliferative DR [PDR]) were reviewed. No significant associations between inner zone arteriolar diameter and retinal NPI overall or in any retinal region. In the outer zone, eyes with thinnest arteriolar calibers (quartile 1) were associated with a 1.7- to 2.4-fold nonperfusion increase across all retinal regions compared to the remaining eyes (P = 0.002 [PP] to 0.048 [FP]). In the outer zone, the percentage of eyes in the thinnest quartile of retinal arteriolar diameter increased with worsening DR severity (mild NPDR: 10% vs PDR: 31%, P = 0.007). This association was not observed when measured within the inner zone (P = 0.129). All venular caliber associations were not statistically significant when corrected for potentially confounding factors. Thinner outer zone retinal arteriolar caliber (quartile 1) was more common in eyes with PPL compared to eyes without PPL (34.1% vs 20.8%, P = 0.017) as were thicker outer venular calibers (quartile 4) (33% vs 21.3%, P = 0.036). Presence of PPL was associated with thinner outer zone arteriolar caliber (109.7 ± 26.5μm vs 123.0 ± 29.5μm, P = 0.001). The association of vascular caliber with nonperfusion and DR severity differs based upon the retinal location at which vascular caliber is measured. Peripheral arterial narrowing is associated with increasing nonperfusion, worsening DR severity and presence of PPL. In contrast, inner zone retinal arteriolar caliber is not associated with these findings.

Ashraf M ，Shokrollahi S ，Pisig AU ，Sampani K ，Abdelal O ，Cavallerano JD ，Robertson G ，Fleming A ，van Hemert J ，Pitoc CM ，Sun JK ，Aiello LP ，Silva PS ... -  《-》

Visualization of 3 Distinct Retinal Plexuses by Projection-Resolved Optical Coherence Tomography Angiography in Diabetic Retinopathy.

Hwang TS ，Zhang M ，Bhavsar K ，Zhang X ，Campbell JP ，Lin P ，Bailey ST ，Flaxel CJ ，Lauer AK ，Wilson DJ ，Huang D ，Jia Y ... -  《-》