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Purpose: To determine the changes of the microvasculature and microstructure in the inner intra-retinal layers in systemic lupus erythematosus (SLE) patients without lupus retinopathy (LR)., Methods: Thirty-two SLE patients (58 eyes) without LR (NLR), 14 patients (22 eyes) with LR and 50 healthy subjects (50 eyes) were enrolled. Spectral domain optical coherence tomography equipped with Angiovue was used to obtain three-dimensional retinal thickness maps and microvascular images of the superficial and deep retinal capillary plexuses (SRCP/DRCP) around the macula. Quantitative analyses were performed using a custom automated algorithm. Disease activity of patients was assessed using the SLE disease activity index (SLEDAI)., Results: Retinal capillary skeleton density of the SRCP in SLE patients without LR was significantly lower than the controls in almost all regions, which further decreased in the LR group (P < .05). No significant changes were evident in DRCP of the NLR group (P > .05). The inner retina in the LR group was significantly thinner than the controls in most regions, though there were only a few regions that were different between the NLR and the control groups (P < .05). There were significant differences of the SLEDAI scores between the two SLE groups., Conclusion: Significantly lower density in SRCP and regional thinning in inner retina were observed in the SLE patients without clinical fundus changes. OCT equipped with Angiovue might be useful in evaluating the microvascular and microstructural disorders of the inner retinal layers in SLE patients, which may contribute a quantitative approach to the early diagnosis and progression of LR., (Copyright © 2019. Published by Elsevier Inc.)

Purpose: To evaluate macular microvascular changes in neuromyelitis optica spectrum disorders (NMOSD) by using optical coherence tomography angiography (OCT-A) and investigate their correlations with neuroaxonal structural damage evaluated with spectral-domain OCT (SD-OCT)., Design: Cross-sectional study., Methods: Twenty eyes of 20 patients with NMOSD and 21 eyes from 21 healthy controls were enrolled. OCT-A was used to obtain microvascular network images of the whole, superficial, and deep retinal capillary plexuses (WRCP, SRCP, and DRCP) in a 3-mm-diameter area around the macula. SD-OCT was used to obtain the intraretinal thickness. Custom automated algorithms quantified the thickness of the intraretinal layers as well as microvascular density of the retinal capillary layers., Results: NMOSD patients showed significantly decreased microvascular density in both SRCP and DRCP (P < .05) compared to controls. The decreased microvascular density in SRCP and DRCP significantly correlated with the frequency of optic neuritis attack (P < .05). Both SRCP and DRCP microvascular density significantly correlated (P < .05) with retinal nerve fiber layer and ganglion cell layer with inner plexiform layer. SRCP microvascular density moderately correlated with visual acuity, while a stronger correlation was found between DRCP and visual acuity., Conclusions: Decreased microvascular density in NMOSD patients correlated with the worsening of their visual acuity. Correlation between microvascular impairment and neuroaxonal thinning revealed that retinal microvascular alteration may contribute to neuroaxonal loss in NMOSD patients. OCT-A with measurable analysis offers a new path of study and will likely be useful as an objective biomarker for detecting microvascular impairment in NMOSD., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Purpose: To assess macular microstructure in eyes with tilted disk syndrome (TDS) and determine the relationship between TDS foveal morphology and visual function., Methods: Twenty-six TDS eyes from 19 children (aged 5∼15 years) with a spherical equivalent refraction (SER) of -3.1 ± 1.3 diopter (D) and 28 control eyes from 14 children (aged 7∼12 years) with a SER of -3.0 ± 0.7 D were recruited. Horizontal and vertical optical coherence tomography scans through the fovea produced images that were segmented into eight intraretinal layers. Thicknesses of the total retina and each layer were measured at the foveal center and 12 other macular locations: 500 μm, 1,000 μm, and 1,500 μm along the horizontal and vertical meridians. The relationships between TDS best correct visual acuity (BCVA) and the presence of photoreceptor inner/outer segment (IS/OS) junction line, IS/OS foveal bulge, and cone outer segment tip (COST) line were evaluated., Results: The thickness of TDS central fovea, 218.94 ± 22.20 μm, was not significantly different from controls. The total retinal thickness in TDS eyes was thinner than controls at all peripheral locations (P < 0.05) except at 500 μm and 1,000 μm superiorly, and 1,500 μm temporally. Tilted disk syndrome intraretinal layer thicknesses in the nasal and inferior regions varied significantly from controls (P < 0.05). Only 80.7% and 23.1% of TDS eyes had a normal foveal bulge and continuous COST line, respectively, compared with 100% and 96.4% of controls. The BCVA of TDS eyes was similar whether or not the foveal bulge or COST line was abnormal., Conclusion: Differences in intraretinal layer thickness may be correlated with defective vision.

Purpose: To identify macular intraretinal layer changes of patients in remission from Behcet's disease (BD) of short and long duration and evaluate the associations with visual acuity (VA)., Methods: Thirty-two eyes from 26 BD patients were enrolled, including 16 eyes with a duration less than 3 years (0.5-2.5 years; BD1) and 16 eyes of longer duration (3-12 years; BD2). Their intraretinal layer thicknesses and integrity of ellipsoid zone (EZ) and interdigitation zone (IZ) were evaluated by spectral-domain optical coherence tomography (SD-OCT). Associations between VA and retinal structural changes were analyzed., Results: Compared to controls, the inner retina was significantly thicker in BD groups, especially the nerve fiber layer (NFL). The outer retinal layer (ORL) was thicker in BD1 in the central and temporal regions and thinner in BD2 compared to controls in all regions. In BD2, there were more eyes with disruption of the EZ and IZ. Worsening VA was correlated with thickening of the NFL and inner nuclear layer (INL), thinning of the ORL, and greater disruption of the EZ and IZ. Multiple linear regression analysis revealed EZ disruption, nasal ORL, inferior NFL, and temporal and nasal INLs were independent predictors of best-corrected (BCVA)., Conclusions: Behcet's disease patients in remission had significant changes in the inner and outer retinal structures, associated with worse VA. Thickness and integrity of the intraretinal layers by SD-OCT and segmentation might be useful predictors for the degree of VA damage in BD remission.

Age-related Macular Degeneration (AMD) and Diabetic Macular Edema (DME) are two common retinal diseases for elder people that may ultimately cause irreversible blindness. Timely and accurate diagnosis is essential for the treatment of these diseases. In recent years, computer-aided diagnosis (CAD) has been deeply investigated and effectively used for rapid and early diagnosis. In this paper, we proposed a method of CAD using vision transformer to analyze optical coherence tomography (OCT) images and to automatically discriminate AMD, DME, and normal eyes. A classification accuracy of 99.69% was achieved. After the model pruning, the recognition time reached 0.010 s and the classification accuracy did not drop. Compared with the Convolutional Neural Network (CNN) image classification models (VGG16, Resnet50, Densenet121, and EfficientNet), vision transformer after pruning exhibited better recognition ability. Results show that vision transformer is an improved alternative to diagnose retinal diseases more accurately. [ABSTRACT FROM AUTHOR]

Introduction. Retinal structural and microvascular damages reflect damage to cerebral microvasculature and neurons. We aimed to investigate neovascular unit abnormalities among patients with large-artery atherosclerosis (LAA) or small-vessel occlusion (SAA) and control subjects. Methods. Twenty-eight LAA patients, forty-one SAA patients, and sixty-five age- and gender-matched controls were recruited. Based on optical coherence tomography angiography (OCTA), retinal capillary vessel density was assessed in the general and local sectors, and the thickness of individual retinal layer was extracted from retinal structural images. The differences between structural and microvascular were analyzed. Results. The superior peripapillary retinal nerve fiber layer (pRNFL) thickness was significantly different among the three groups, and the LAA group had the thinnest thickness. Compared to the control group, the deep retinal capillary vessel density in other two stroke subgroups were significantly reduced in all regions except in the inferior region (P < 0.05), and the fractal dimension in C2 and C4 regions of deep retina was significantly lower in the LAA group (P < 0.05). Discussion. Compared with superficial microvascular network, deep microvascular network is more sensitive to ischemic stroke. In addition, we have demonstrated quadrant-specific pRNFL abnormalities in LAA and SAA patients. Superior quadrant pRNFL thickness differences between stroke subgroups may suggest that changes in retinal nerve fiber layer are more sensitive to subtype identification than changes in retinal microvascular structure. All in all, the alteration in retinal structural and microvascular may further elucidate the role of the neovascular unit in ischemic stroke, suggesting that the combination of these two indicators could be used for subtype identification to guide prognosis and establish a risk prediction model. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the repeatability, reproducibility, and agreement of thickness profile measurements of eight intra-retinal layers determined by an automated algorithm applied to optical coherence tomography (OCT) images from two different instruments. Methods: Twenty normal subjects (12 males, 8 females; 24 to 32 years old) were enrolled. Imaging was performed with a custom built ultra-high resolution OCT instrument (UHR-OCT, ∼3 µm resolution) and a commercial RTVue100 OCT (∼5 µm resolution) instrument. An automated algorithm was developed to segment the macular retina into eight layers and quantitate the thickness of each layer. The right eye of each subject was imaged two times by the first examiner using each instrument to assess intra-observer repeatability and once by the second examiner to assess inter-observer reproducibility. The intraclass correlation coefficient (ICC) and coefficients of repeatability and reproducibility (COR) were analyzed to evaluate the reliability. Results: The ICCs for the intra-observer repeatability and inter-observer reproducibility of both SD-OCT instruments were greater than 0.945 for the total retina and all intra-retinal layers, except the photoreceptor inner segments, which ranged from 0.051 to 0.643, and the outer segments, which ranged from 0.709 to 0.959. The CORs were less than 6.73% for the total retina and all intra-retinal layers. The total retinal thickness measured by the UHR-OCT was significantly thinner than that measured by the RTVue100. However, the ICC for agreement of the thickness profiles between UHR-OCT and RTVue OCT were greater than 0.80 except for the inner segment and outer segment layers. Conclusions: Thickness measurements of the intra-retinal layers determined by the automated algorithm are reliable when applied to images acquired by the UHR-OCT and RTVue100 instruments. [ABSTRACT FROM AUTHOR]

The retina provides a window to study the pathophysiology of cerebrovascular diseases. Pathological retinal microvascular changes may reflect microangiopathic processes in the brain. Recent advances in optical imaging techniques have enabled the imaging of the retinal microvasculature at the capillary level, and the generation of high-resolution, non-invasive capillary perfusion maps (nCPMs) with the Retinal Function Imager (RFI). However, the lack of quantitative analyses of the nCPMs may limit the wider application of the method in clinical research. The goal of this project was to demonstrate the feasibility of automated segmentation and fractal analysis of nCPMs. We took two nCPMs of each subject in a group of 6 healthy volunteers and used our segmentation algorithm to do the automated segmentation for monofractal and multifractal analyses. The monofractal dimension was 1.885±0.020, and the multifractal dimension was 1.876±0.010 (P =0.108). The coefficient of repeatability was 0.070 for monofractal analysis and 0.026 for multifractal analysis. This study demonstrated that the automatic segmentation of nCPMs is feasible for fractal analyses. Both monofractal and multifractal analyses yielded similar results. The quantitative analyses of microvasculature at the capillary level may open up a new era for studying microvascular diseases such as cerebral small vessel disease. [ABSTRACT FROM AUTHOR]