The Assessment of Radial Peripapillary Capillary Vessel Density in Adult Children of Patients With Primary Open Angle Glaucoma.

PRCIS: The observed decrease in radial peripapillary capillary vessel density among adult children of individuals with primary open angle glaucoma, in comparison to controls, suggests the possibility of early microvascular alterations in the eyes of these at-risk individuals. PURPOSE: To compare the radial peripapillary capillary vessel density (RPCVD) and peripapillary retinal nerve fiber layer (RNFL) thickness values of eyes between healthy adults with a maternal or paternal history of primary open angle glaucoma (POAG) and age-matched healthy controls without a family history of POAG. MATERIALS AND METHODS: RPCVD values and RNFL thicknesses in the peripapillary region and 4 quadrants (superior, inferior, nasal, and temporal) were evaluated using optical coherence tomography angiography among 30 adult children of patients with POAG and 30 age-matched healthy controls without a family history of POAG. RESULTS: The mean whole image RPCVD (51.6±1.7% vs. 49.8±1.7%, P =0.0006) and average RPCVD (54.7±1.7% vs. 53.2±2.1%, P =0.006) values were significantly lower in the adult children of patients with POAG compared with age-matched healthy controls without a family history of POAG. There was no difference in terms of RNFL thickness values in any region. CONCLUSION: Despite having similar RNFL thickness values to the control group, the observation of lower RPCVD in the eyes of adult children of POAG patients may indicate potential early vascular alterations. The result of the present study encourages further longitudinal studies to determine the potential importance of the underlying vascular alterations in these high-risk individuals.

Assessment of Detailed Photoreceptor Structure and Retinal Sensitivity in Diabetic Macular Ischemia Using Adaptive Optics-OCT and Microperimetry.

Purpose: The purpose of this study was to assess density and morphology of cone photoreceptors (PRs) and corresponding retinal sensitivity in ischemic compared to nonischemic retinal capillary areas of diabetic eyes using adaptive optics optical coherence tomography (AO-OCT) and microperimetry (MP). Methods: In this cross-sectional, observational study five eyes of four patients (2 eyes with proliferative diabetic retinopathy (DR) and 3 eyes moderate nonproliferative DR) were included. PR morphology and density was manually assessed in AO-OCT en face images both at the axial position of the inner-segment outer segment (IS/OS) and cone outer segment tips (COSTs). Retinal sensitivity was determined by fundus-controlled microperimetry in corresponding areas (MP-3, Nidek). Results: In AO-OCT, areas affected by capillary nonperfusion showed severe alterations of cone PR morphology at IS/OS and COST compared to areas with intact capillary perfusion (84% and 87% vs. 9% and 8% of area affected for IS/OS and COST, respectively). Mean reduction of PR signal density in affected areas compared to those with intact superficial capillary plexus (SCP) and deep capillary plexus (DCP) perfusion of similar eccentricity was -38% at the level of IS/OS (P = 0.01) and -39% at the level of COST (P = 0.01). Mean retinal sensitivity was 10.8 ± 5.4 in areas affected by DCP nonperfusion and 28.2 ± 1.5 outside these areas (P < 0.001). Conclusions: Cone PR morphology and signal density are severely altered in areas of capillary nonperfusion. These structural changes are accompanied by a severe reduction of retinal sensitivity, indicating the importance of preventing impaired capillary circulation in patients with DR.

Optical Coherence Tomography Angiography Assessment of the Peripapillary Vessel Density and Structure in Patients with Nonarteritic Anterior Ischemic Optic Neuropathy: A Meta-Analysis.

BACKGROUND: This meta-analysis is aimed at assessing the peripapillary vessel density (VD) and structural outcomes using optical coherence tomography angiography (OCTA) in patients with nonarteritic anterior ischemic optic neuropathy (NAION). METHODS: A comprehensive search of PubMed, Embase, Cochrane Library, and Web of Science databases for literature comparing VD and structural outcomes in patients with NAION and controls was performed. Mean differences (MDs) and its 95% confidence interval (CI) were calculated for continuous estimates. Review Manager (V5.30) was used for analysis. RESULTS: Fourteen published studies met the requirement. The radial peripapillary capillary (RPC) whole enface VD measured by OCTA was significantly lower in patients with NAION compared to that of the controls (MD = -10.51, P < 0.00001). The RPC inside disc VD was significantly decreased in the NAION group than that in the control group (MD = -8.47, P < 0.00001). For RPC peripapillary VD, there was a statistically significant difference between patients with NAION and the controls (MD = -12.48, P < 0.00001). The peripapillary retinal nerve fibre layer (p-RNFL) thickness was significantly lower in patients with NAION in comparison to the controls (MD = -22.18, P = 0.004). The ganglion cell complex (GCC) thickness in the macular zone of NAION patients was remarkably reduced compared to that in the controls (MD = -17.18, P = 0.0002). CONCLUSIONS: The findings suggested that the peripapillary VD and RNFL thickness were attenuated, and the macular GCC thickness was reduced in patients with NAION. OCTA, in the future, may facilitate the diagnosis and monitoring of patients with NAION.

Assessment of Perfused Peripapillary Capillaries and Peripapillary Capillary Density Maps in Glaucoma Patients.

INTRODUCTION: Monitoring and diagnosing glaucoma until 2017 included funduscopy, IOP measurements, gonioscopy, pachymetry, as well as visual field tests, optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A). Radial peripapillary capillaries (RPC) can be observed by fluorescein angiography, as well as histologically - superficial and deep capillary layer. AIM: To correlate density of radial peripapillary capillary network (RPC) and retinal nerve fiber layer (RNFL) thickness in eight peripapillary segments in patients with a primary open angle glaucoma (POAG) which have the disease under 10 years of duration, over 10 years of duration and in a group of healthy patients. METHODS: This is a cross-sectional review which included three groups of patients: POAG patients under 10 years of disease duration, over 10 years of disease duration and control group of patients. The study is performed on the commercial optical coherence tomography angiography system (AngioVue, Avanti RTVue-XR, Optovue, CA). Sectoral RPC density values, RPC maps and RNFL thickness were analyzed in three groups of patients, data was compared and correlation between parameters was examined. RESULTS: Mean RPC Density values in both superior segments (S1, S2) were significantly lower in patients with glaucoma over 10 years of disease duration compared to patients with glaucoma under 10 years of disease duration (p<0.05). Statistically significant positive correlation was established between RNFL thickness and RPC density in all eight peripapillary segments. CONCLUSION: Analysis of radial peripapillary capillary network density on optical coherence tomography angiography may provide an earliest functional sign of progressive optic nerve disease and new insights into the pathophysiology of glaucomatous damage.

Assessment of superficial and deep retinal vessel density in systemic lupus erythematosus patients using optical coherence tomography angiography.

PURPOSE: The aim of this study is to evaluate the retinal microvascular density in SLE patients using optical coherence tomography angiography (OCTA) and to correlate vascular density with the disease activity and damage risk. METHODS: Twenty eyes of 20 SLE patients were compared with 20 eyes of normal subjects. The retinal capillary plexuses were examined by OCTA. The disease activity and damage risk were evaluated by the SLEDAI-2 K and SLICC/ACR SDI scoring systems. RESULTS: No difference was found between SLE patients' central foveal thickness (CFT) and foveal avascular zone (FAZ) area and the normal (P > 0.05). SLE patients had slightly lower superficial vessel densities than normal in the upper and lower macular regions (P < 0.05), sparing the middle sectors (P > 0.05). In the deep plexus, vessel density loss was detected in all sectors (P < 0.001). The vessel density in 300-µm-wide region around the FAZ (FD-300) and the acircularity index (AI) were affected in the SLE in comparison to the normal group (P < 0.05). No significant correlation was found between the SLEDAI-2 k and the retinal vessel density in either layer, while the SLICC/SDI had moderate inverse correlation with vessel density in some sectors (P < 0.05). Receiver operating characteristic (ROC) curve analysis showed that the deep capillary plexus had high sensitivity and specificity for detecting vascular damage in SLE patients. CONCLUSIONS: OCTA permits noninvasive quantitative assessment of retinal vessel density in SLE, allowing early detection of altered retinal circulation. Vessel density could be included in future assessment of SLE activity and damage scores.

Quantitative assessment of the retinal microvasculature and choriocapillaris in myopic patients using swept-source optical coherence tomography angiography.

PURPOSE: To study the retinal capillary microvasculature and the choriocapillaris (CC) in myopic eyes using swept-source optical coherence tomography angiography (SS-OCTA). METHODS: Patients with high myopia (≥ - 6D; axial length ≥ 26.5 mm), moderate myopia (≥ - 3D, < - 6D), and age-matched healthy subjects presenting to the Shanghai General Hospital and Doheny-UCLA Eye Centers were enrolled in this prospective, multicenter study. Any subjects with evidence of macular abnormalities suggestive of pathologic myopia were excluded. SS-OCTA at both sites was performed using a Zeiss PLEX Elite instrument with a 6 × 6 mm scan pattern centered on the fovea. Two repeated volume scans were acquired for image averaging. The instrument pre-defined en face slab of the superficial and deep retinal capillary microvasculature was used to isolate and display the superficial and deep retinal capillaries. A slab spanning from 21 to 31 µm deep to the RPE fit line was used to isolate and display the CC. The OCTA images were exported for averaging using Image J. Littmann's method and the Bennett formula were applied to adjust for the impact of magnification in the high and moderate myopia groups. The resultant images were then binarized. Though projection artifact removal software was used, regions below the large superficial retinal vessels were excluded for quantitative analyses of the deep retinal capillary plexus and the CC. Vessel density (VD) and vessel length density (VLD) of the superficial and deep retinal capillary plexus (SCP, DCP) and CC flow deficit (FD) were analyzed, quantified, and compared between different groups. RESULTS: Twenty-five eyes of 25 patients with high myopia, 25 eyes of 25 patients with moderate myopia, and 25 eyes of 25 normal age-matched controls were included in this study. The VD of the SCP was lower in the high myopia group compared with the emmetropic control groups (p < 0.05), but the VD of the DCP demonstrated no significant difference among the three groups (p > 0.05). The VLDs of the SCP were lower in the high and moderate myopia groups compared with the control group (p < 0.05), while the VLD of the DCP was lower in the high myopia group compared with the moderate myopia and emmetropic control group (p < 0.05). The CC FD% in the high myopia group was significantly greater than both the control and moderate myopia subjects (p < 0.05). Of note, the severity of the CC flow deficit was not correlated with choroidal thickness (p > 0.05). CONCLUSION: The retinal microvasculature may demonstrate alterations in highly myopia eyes. The CC in macular regions shows greater impairment in eyes with high myopia compared with eyes with lesser degrees of myopia, and these deficits are already present in the absence of features of pathologic or degenerative myopia. The threshold of CC FD leading to myopic maculopathy remains to be defined.

Quantitative Assessment of Retinal Capillary Vessel Density and Foveal Avascular Zone Area in Central Serous Chorioretinopathy Using OCTA.

PURPOSE: To quantitatively assess the retinal capillary vessel density (VD) and foveal avascular zone (FAZ) area in acute and chronic central serous chorioretinopathy (CSC) patients compared to healthy subjects using optical coherence tomography angiography (OCTA) and determine their correlation with visual acuity (VA). METHODS: This was a cross-sectional, case-control study. All subjects were divided into three groups: acute CSC, chronic CSC, and healthy controls. The best-corrected VA test, optical coherence tomography, and OCTA were performed on the same day. In this study, we recorded and compared the main data of FAZ and VD in 3 × 3 mm OCTA images among three groups, also calculated the correlation between OCTA variables and VA in CSC patients. RESULTS: A total of 148 subjects (148 eyes) were included in this study, with 50 eyes in acute CSC, 48 eyes in chronic CSC, and 50 eyes in control groups. The mean age was 50.11 ± 8.14 years. Chronic CSC had the significantly lowest VD both on the superficial and deep retina and the largest FAZ (0.39 ± 0.13 mm2) compared to acute CSC and controls (all p < 0.05). There was no statistical difference between acute CSC and controls on VD or FAZ (both p > 0.05). In chronic CSC, both the decreased VD on deep retina and expanded FAZ were correlated with a worse VA (both p < 0.05). CONCLUSIONS: OCTA could serve as a reliable tool to evaluate different courses of CSC quantitively. In 3 × 3 mm OCTA images, both decreased VD and expanded FAZ were observed in chronic CSC patients.

Glomerular Endothelial Cells: Assessment of Barrier Properties In Vitro.

Endothelial cells form the inner lining of all blood vessels and play a vital role in regulating vascular permeability. This applies to the circulation in general and also to specific capillary beds including the renal glomerular capillaries. Endothelial dysfunction, including increased permeability, is a key component of diabetes-induced organ damage. Endothelial cells together with their glycocalyx, grown on porous membranes, provide an excellent model to study endothelial permeability properties. Here we describe the measurement of two characteristics of glomerular endothelial cell (GEnC) monolayers: electrical resistance and macromolecular passage. Trans-endothelial electrical resistance provides a measure of small-pore pathways across the endothelium and provides an index of monolayer confluence and cell-cell junction integrity. Measurement of macromolecular passage provides an index of large-pore pathways and use of labeled albumin provides direct relevance to the clinically important parameter of albuminuria. The combination of the two approaches provides a fantastic tool to elucidate endothelial barrier function in vitro including in response to cytokines, pathological stimuli, and potential therapeutic agents.

Normative Data Assessment of Vessel Density and Foveal Avascular Zone Metrics Using AngioScan Software.

Purpose: To establish a normative database for macular and peripapillary vessel densities (VD) and foveal avascular zone (FAZ) metrics in healthy subjects with the new version of AngioScan software of RS-3000 Advance (Nidek Co, Ltd) optical coherence tomography angiography (OCT-A) device.Methods: The study design was prospective and cross-sectional. VDs of the SCP, deep capillary plexus (DCP), retinal peripapillary capillary plexus (RPCP) and FAZ area, perimeter and circularity index (CI) along with the structural OCT measurements were scanned by using the Nidek's RS-3000 Advance OCT-A device in healthy subjects. The new version of the AngioScan software was used for analytics. The relations between the OCT-A parameters with age, gender and OCT parameters were analyzed.Results: A total of 128 right eyes of 128 subjects (50% female) were included in this study. We divided subjects into 3 groups in accordance with age; 19-39 years to Group 1, 40-59 years to Group 2, >60 y. to Group 3. The mean SCP and DCP VDs were 41.25 ± 2.51% and 36.01 ± 5.07% respectively (P < .001). The DCP VD was significantly different between groups (P = .001). The mean FAZ area, perimeter and CI were 0.33 ± 0.12 mm2, 2.68 ± 0.6 mm and 0.47 ± 0.09 respectively. Only FAZ CI significantly differed between groups (P = .003). The FAZ area was significantly greater in female subjects than males (P = .025). The SCP and DCP VDs were inversely correlated with FAZ area and perimeter (P < .05).Conclusion: Our study provided for the first time the normative data of the recently updated AngioScan software of Nidek. Additional studies are needed to define pathological vascular changes in ocular and systemic diseases with this new software.

Quantitative Assessment of Choriocapillaris Flow Deficits in Eyes with Advanced Age-Related Macular Degeneration Versus Healthy Eyes.

PURPOSE: To compare choriocapillaris (CC) flow deficits in eyes with geographic atrophy (GA) or choroidal neovascularization (CNV) associated with age-related macular degeneration (AMD) and age-matched healthy control subjects. DESIGN: Cross-sectional study. METHODS: Patients with GA due to AMD, CNV due to AMD, and age-matched healthy subjects presenting to the Doheny-UCLA Eye Centers were enrolled in this cross-sectional institutional review board-approved study. Swept-source optical coherence tomography angiography was performed using a Zeiss PLEX Elite instrument with a 6 × 6-mm scan pattern centered on the fovea. Two repeated volume scans were acquired to allow for image averaging. The instrument predefined en face slab of the CC was used to isolate and display the CC. Both the structural and optical coherence tomography angiography slabs from this location were exported for averaging and signal compensation using Image J. The resultant image was then binarized. The CC flow deficit percentage (FD%) was computed in 4 peripheral 1 × 1-mm squares located at the corners of the images to allow comparison between equidistant regions unaffected by atrophy or CNV. RESULTS: Twenty eyes of 20 subjects were enrolled in each of the 3 groups (CNV, GA, normal) for this study. The average CC FD% of the 4 peripheral squares was 17.24% ± 2.86% in GA eyes, 15.55% ± 1.03% in CNV eyes, and 15.31% ± 0.93% in healthy controls of a similar age. The FD% in GA eyes was significantly greater than in both normal eyes and eyes with CNV (p= 0.012 and 0.038 respectively). The difference in FD% was not significantly different between CNV eyes and normal eyes for the tested peripheral macular regions (P = .678). CONCLUSIONS: The CC in peripheral macular regions in eyes with GA shows greater impairment than in eyes with CNV.

Assessment of macular vascular plexus density using optical coherence tomography angiography in cases of strabismic amblyopia.

PURPOSE: To evaluate the superficial retinal vascular plexus density using optical coherence tomography angiography (OCTA) in cases of strabismic amblyopia. METHODS: Ten eyes of 10 patients with purely strabismic amblyopia underwent detailed ocular evaluation followed by the assessment of the superficial retinal plexus vascular density using OCTA (Topcon DRI OCT Triton, Swept Source OCT, Topcon, Japan). Ten contralateral normal eyes of the same patients were considered as control. All these 20 eyes underwent a 4.5 × 4.5 mm cube scan OCTA centered at the fovea. Using the Topcon propriety software all 20 eyes were assessed for the capillary plexus density of the superficial retinal vascular plexus along the superior, inferior, nasal, and temporal quadrants centered at the fovea. The numerical values were statistically assessed using a paired t-test with respect to each quadrant between the normal and the pathological eyes. RESULTS: The average age of patients was 16 years and eight patients were males. The mean superficial retinal vascular plexus density along the superior, inferior, nasal, and temporal quadrants in normal and pathological eyes were 49.25 ± 30.34 and 48.93 ± 2.85, 47.22 ± 4.11 and 47.37 ± 4.8, 45.54 ± 1.55 and 43.81 ± 4.21, and 46.26 ± 4.63 and 46.38 ± 5.40, respectively. Similarly, the capillary densities along the central were 17.84 ± 3.49 and 17.24 ± 2.44 in normal and pathological eyes. The differences among all these four quadrants and central area were not statistically significant (P-values > 0.05 for all four quadrants and central area) as compared with the normal eyes. CONCLUSION: The superficial retinal vascular plexus density of a 4.5 × 4.5 mm cube centered at the fovea of eyes of cases of strabismic amblyopia is similar to that of normal eyes.

An integrative approach for the assessment of peritubular capillaritis extent and score in low-grade microvascular inflammation-associations with transplant glomerulopathy and graft loss.

Background: Peritubular capillaritis (ptc), reported by the ptc score, is a major feature of kidney allograft rejection and microvascular inflammation (MVI). MVI sum scores (ptc + glomerulitis score ≥2) are accepted diagnostic surrogates of human leucocyte antigen (HLA)-antibody interaction. However, low-grade inflammation is common and ptc scores (number of leucocytes/capillary) may not mirror all aspects of ptc morphology. Recently we observed a relationship of the diffuse extent of ptc (inflammation of >50% of the renal cortex) with graft loss and significantly higher donor-specific antibody levels, suggesting potential inclusion of diffuse ptc as an additional surrogate of antibody-antigen interaction. Methods: We sought to assess how a combination of ptc score and extent in low-grade inflammation (ptc1) affects transplant glomerulopathy (TG) and graft loss risk. Patients (n = 616) were assessed for MVI in first indication biopsies. Cases with a ptc score of 1 but diffuse extent (ptc1diffuse, g-score = 0, n = 26) were considered additional surrogates of HLA-antibody interaction and compared with MVI ≥2 and MVI <2. Results: The ptc1diffuse and MVI score ≥2 subjects had worse graft survival (42% and 59%) compared with an MVI score <2 (70%) (P = 0.002). The incorporation of ptc1diffuse in the MVI score ≥2 increased the receiver operating characteristics curve for TG [area under the curve (AUC) 0.602; P = 0.008] compared with a Banff MVI score ≥2 (AUC 0.56; P = 0.12); cases with baseline TG were excluded. In multivariate analysis, ptc1diffuse remained independently related to TG (odds ratio 3.89; P = 0.008) and graft loss (hazard ratio 2.64; P = 0.001) even after inclusion of all rejection episodes. Conclusion: An integrated view of ptc morphology including diffuse ptc in MVI is superior for TG and graft loss risk assessment.

Quantitative Assessment of the Choriocapillaris in Patients With Retinitis Pigmentosa and in Healthy Individuals Using OCT Angiography.

BACKGROUND AND OBJECTIVE: To characterize the choriocapillaris (CC) vasculature in patients with retinitis pigmentosa (RP) and healthy controls using optical coherence tomography angiography (OCTA). PATIENTS AND METHODS: The CC of patients with RP and controls was analyzed using OCTA. Areas of no-flow, termed flow voids (FVs), were denoted in both. Comparisons between groups were done using Wilcox tests and generalized estimating equations. RESULTS: Fifty-four patients were included. There was a significant difference in spherical equivalent (P < .001). The number of FV was 55.5 ± 20.1 in the RP eyes versus 30.7 ± 16.3 in the controls (P < .001). The average FV area was 0.33 ± 0.12 mm2 in the RP eyes and 0.18 ± 0.10 mm2 in the controls (P < .001). CONCLUSIONS: There are significantly more FV in patients with RP than in healthy subjects, suggesting it is vital to understanding pathophysiology of RP. Further studies should be done to determine if the compromised CC is a result or cause of RP. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:e122-e128.].

Assessment of capillary dropout in the superficial retinal capillary plexus by optical coherence tomography angiography in the early stage of diabetic retinopathy.

BACKGROUND: To assess capillary dropout in the superficial retinal capillary plexus (SCP) by optical coherence tomography angiography (OCTA) in the early stage of diabetic retinopathy (DR). METHODS: This study was a cross-sectional observational study. Patients that underwent OCTA examinations in our hospital between November 2015 and May 2016 were included in the study. The subjects were divided into two groups: A) normal controls (41 eyes of 41 subjects) and B) the DR patients (49 eyes of 49 patients with mild non-proliferative DR (NPDR)). The retinal thickness and SCP vessel density were analyzed using built-in software in nine sections of the macular area; whole scan area; fovea; parafovea; and sub-sections of the parafovea, superior-hemi, inferior-hemi, temporal, superior, nasal, and inferior. The correlation between vessel density and retinal thickness was also analyzed. RESULTS: The SCP density was significantly lower (P < 0.05) in mild NPDR patients than in normal controls in all areas, with the exception of the fovea (P > 0.05). In the parafovea, superior-hemi, inferior-hemi, temporal, and nasal sectors of group B, the SCP density was negatively correlated with the corresponding retinal thickness (P < 0.05). Specifically, as the SCP density decreased, retinal thickness increased. CONCLUSIONS: In the early stage of NPDR, retinal capillary dropout and retinal thickness changes can be clearly captured and analyzed by OCTA. The results confirm a negative correlation between vessel density and retinal thickness in diabetic patients. This noninvasive technique could be applied for DR detection and monitoring. Further study with a larger sample size is warranted.

Numerical modeling of fluid and oxygen exchanges through microcirculation for the assessment of microcirculation alterations caused by type 2 diabetes.

Type 2 diabetes mellitus (DM2) is frequently accompanied by microcirculation complications, including structural and functional alterations, which may have serious effects on substance exchanges between blood and interstitial tissue and the health of organs. In this paper, we aim to study the influence of microcirculation alterations in DM2 patients on fluid and oxygen exchanges through a model analysis. A fluid flow and oxygen transport model were developed by considering the interplay between blood in capillary network and interstitial tissue. The two regions were separately represented by 1D network model and 3D volume model, and the immersed boundary method (IBM) was adopted to solve fluid and mass transfer between these two regions. By using the model, the steady flow field and the distributions of oxygen in capillary network and surrounding tissue were firstly simulated. In the interstitial volume, fluid pressure and oxygen tension decreased with the increase of distance from the network; in the network, oxygen tension in blood plasma dropped from 100 mm Hg at the entrance to about 40 mm Hg at the exit. We further tested several structural and functional disorders related to diabetic pathological conditions. Simulated results show that the impaired connectivity of the network could result in poor robustness in maintaining blood flow and perfused surface; under high fluid permeability conditions of capillary walls, the pressure gradient was much larger around the capillary bed, and this alteration led to a saturation level of the interstitial pressure when lymphatic flow drainage can't work effectively; the variations in network connectivity and permeability of capillary wall also had unfavorable influence on oxygen distributions in interstitial tissue. In addition, when the oxygen releasing capacity of hemoglobin was confined by glycosylated hemoglobin (HbA1) in the case of diabetes, the plasma could not be complemented with adequate oxygen and thus the hypoxic tissue range will be extended. This study illustrates that when microcirculation disturbances, including the structure of capillary network, the wall osmosis property and the capacity of blood binding oxygen occur in DM2, some negative impacts are raised on microvascular hemodynamics and metabolism circumstance of interstitial tissue.

Differential microvascular assessment of retinal vein occlusion with coherence tomography angiography and fluorescein angiography: a blinded comparative study.

PURPOSE: To compare the imaging of retinal vein occlusion (RVO) with optical coherence tomography angiography (OCTA) and fluorescein angiography (FA) and evaluate their roles in clinical management. METHODS: RVO patients who underwent imaging with both FA and OCTA from 1 June 2015-31 December 2015 were enrolled. An independent retinal specialist blinded from patient identity assessed the FA and OCTA reports. The pixel counting technique was used for FAZ size measurement. A significant level of p < 0.05 was taken for correlation and agreement analysis. RESULTS: On OCTA, the mean FAZ size was 0.382 ± 0.152 mm2 and 0.606 ± 0.136 mm2 for the superficial and deep retinal layers, respectively, with significant correlation (p = 0.004). On FA, the mean FAZ size was 0.352 ± 0.158 mm2, better correlated with OCTA at the superficial (p = 0.062) than the deep retinal layer (p = 0.122). Between FA and OCTA, good agreement was found for microaneurysms (100%, p = 0.001) and venous congestion (83.33%, p = 0.028), but not capillary non-perfusion (p = 0.217) and venous tortuosity (p = 0.546). OCTA also revealed more capillary non-perfusion than FA (91.67 vs. 58.33%). The presenting best-corrected visual acuity was significantly correlated with capillary non-perfusion on OCTA (p = 0.001). CONCLUSION: OCTA and FA are complementary tools in RVO assessment. While OCTA is more precise in the assessment of FAZ and capillary non-perfusion, FA offers better vascular imaging of the peripheral retina.

Retinal Microvasculature in Nonproliferative Diabetic Retinopathy: Automated Quantitative Optical Coherence Tomography Angiography Assessment.

PURPOSE: To perform a qualitative and quantitative assessment of the foveal microvasculature in eyes with diabetic maculopathy using optical coherence tomography angiography (OCT-A). METHODS: Retrospective case series of 48 eyes with diabetic maculopathy and 47 healthy eyes evaluated by Spectralis OCT-A. Perifoveal arcade disruptions, linear vascular dilations, microaneurysms, intraretinal microvascular abnormalities and flow-void areas were qualitatively analyzed on OCT angiograms both for the superficial (SCP) and deep (DCP) capillary plexuses. A fully automated microstructural analysis of the foveal avascular zone (FAZ) metrics, vascular and avascular surfaces was performed. Quantitative values from diabetic patients were compared with those of healthy subjects. RESULTS: A moderate agreement between SCP and DCP in terms of diabetes-induced vascular lesions in the qualitative assessment was shown. The comparative quantitative analysis between SCP and DCP in diabetic patients revealed a statistically significant difference (p < 0.05) in terms of FAZ perimeter and FAZ surface. No statistically significant difference was shown in total vascular and avascular surfaces. A statistically significant difference between the diabetic and control groups was noticed both for SCP and DCP considering FAZ metrics and vascular surfaces. CONCLUSIONS: A qualitative and quantitative OCT-A approach on retinal vascular perfusion may offer an objective and reliable method for monitoring disease progression in diabetic retinopathy.

Integration of capillary microscopy and dermoscopy into the rheumatology fellow curriculum.

OBJECTIVES: This study evaluates a novel, three-part nailfold capillaroscopy training curriculum for adult and paediatric rheumatology fellows. METHODS: All rheumatology fellows training at an academic medical centre took part in the three-part nailfold capillaroscopy curriculum. Tests of fellows' usage, interest, confidence, and ability in nailfold capillaroscopy were taken at multiple time-points throughout the curriculum. RESULTS: Fellows self-reported high levels of interest, increased confidence in delineating normal and abnormal nailfold capillaries (p=0.03) and increased usage of nailfold capillaroscopy (p=0.09). The ability of fellows to identify normal nailfold capillaries (p=0.03) and systemic sclerosis-specific nailfold capillary changes, such as neoangiogenesis (p<0.001), also increased. CONCLUSIONS: The curriculum was feasible and led to improved ability of learners to distinguish normal from abnormal and to recognise and describe systemic sclerosis-specific nailfold capillary changes. This curriculum also led to improved confidence in examining nailfold capillaries and increased usage of this skill in rheumatologic consultation.

CHOROIDAL THICKNESS IN PATIENTS WITH CENTRAL SEROUS CHORIORETINOPATHY: Assessment of Haller and Sattler Layers.

PURPOSE: To investigate subfoveal choroidal thickness and subanalyze Haller and Sattler layers in eyes with central serous chorioretinopathy (CSC), uninvolved fellow eyes, and eyes of healthy controls using enhanced depth imaging optical coherence tomography. METHODS: Ocular findings and clinical features of 31 eyes with CSC, 24 fellow eyes and eyes of 30 healthy controls were analyzed retrospectively from October, 2014 to March, 2015. Subfoveal choroidal thickness was measured using enhanced depth imaging optical coherence tomography, and the thicknesses of Haller and Sattler layers were analyzed. RESULTS: Mean subfoveal choroidal thickness and mean thickness of Haller layer were significantly greater in CSC than in fellow eyes (P = 0.043 and P = 0.036, respectively) and in normal control eyes (P < 0.001 each), and those of fellow eyes in CSC patients were significantly thicker than those in normal control eyes (P = 0.018 and P = 0.017, respectively). The thickness of Sattler layer did not differ significantly among these groups (P = 0.519). CONCLUSION: Subfoveal choroidal thickness and the thickness of Haller layer were increased not only in affected but also in uninvolved fellow eyes of CSC patients. Nonvascular smooth muscle cells of the choroid may play a role in the pathophysiology of CSC, in response to increased sympathetic tone.