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Copyright of Arquivos Brasileiros de Oftalmologia is the property of Arquivos Brasileiros de Oftalmologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The small retinal vessels reflect cerebral microcirculation and its fractal dimension (D f), representing the complexity of the retinal microcirculation. However, the connection between retinal circulation and cognitive function lacked consistent and longitudinal evidence. This study aimed to explore the association between retinal vascular complexity and cognitive impairment over time in non-demented community-dwelling older adults. This four-year prospective cohort study (2015–2019) is part of the ongoing Taiwan Initiative for Geriatric Epidemiological Research (TIGER, 2011 to present). Of the 434 older adults (age >65) recruited, 207 participants were included for analysis. The retinal vascular D f was assessed by baseline images from fundus photography (2015–2017). Global (Montreal Cognitive Assessment-Taiwanese version, MoCA-T) and domain-specific cognition were assessed at the baseline and 2-year follow-up (2017–2019). The multivariable linear regression models and generalized linear mixed models were used to evaluate the association of D f with cognitive decline/impairment over time. Decreased left retinal vascular complexity was associated with poor attention performance (β = −0.40). As follow-up time increased, decreased vascular complexity was associated with poor memory performance (right: β = −0.25; left: β = −0.19), and decreased right vascular complexity was associated with poor attention performance (β = −0.18). Low retinal vascular complexity of the right or left eye may be differentially associated with cognitive domains in community-dwelling older adults over two years. The retinal vascular D f of either eye may be served as a screening tool for detecting cognitive impairment in the preclinical phase of dementia. [ABSTRACT FROM AUTHOR]

Copyright of Arquivos Brasileiros de Oftalmologia is the property of Arquivos Brasileiros de Oftalmologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives: To collect information about the retinal blood flow variations and other choroidal and retinal parameters during a prolonged effort such as marathon running.Design: Non-randomized prospective cohort study.Methods: Patients were recruited through an information campaign at the Rothschild Foundation Hospital (Paris, France). A first visit (V1) was planned in the month before the marathon. All participants underwent blood pressure measurement, fundus photography, spectral domain-optical coherence tomography (SD-OCT) and OCT-angiography (OCT-A). A second visit (V2) was scheduled within one hour of crossing the finish line. The same tests were repeated, using the same equipment.Results: Of the 31 runners who were included, 29 finished the marathon and attended V2. At baseline, various ophthalmological abnormalities were found in 45.2% of the 58 eyes, among which almost a third concerned the optic nerve and a quarter the pachychoroid spectrum. A significant decrease in retinal vascular plexus density was found between V1 and V2 (p<0.01). While median macular and retinal nerve fiber layer (RNFL) thicknesses significantly increased after the marathon (p<0.01), median choroidal thickness significantly decreased (p<0.01). Both systolic and diastolic blood pressures significantly decreased (p<0.01 and p=0.021 respectively).Conclusions: Prolonged physical effort impacts the structure and vascularization of the retina and the choroid. Hypoxia and dehydration due to such an effort may induce a low ocular blood flow rate resulting in a choroidal thinning, contrasting with a transient subclinical ischemic edema of the inner retina and optic nerve head.Clinical Trial Registration Number: NCT03864380. [ABSTRACT FROM AUTHOR]

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The prevalence of high childhood blood pressure (BP) is rising globally and has been associated with subclinical vascular impairments in children. Longitudinal data on the association of microvascular alterations with the development of high BP in children are lacking. We aimed to analyze the association of central retinal arteriolar (CRAE) and venular (CRVE) diameters with development of higher BP over 4 years in young school children. In 2014, 391 children aged 6 to 8 years were screened for BP and retinal vessel diameters using standardized protocols. Retinal vessel analysis was performed using a retinal vessel analyzer to determine CRAE and central retinal venular equivalent. In the follow-up of 2018, all parameters were assessed in 262 children using the same standardized protocols. During follow-up, systolic and diastolic BP increased significantly (Δ 3.965±8.25 and 1.733±7.63 mm Hg, respectively), while CRAE decreased by Δ -6.325±8.55 µm without significant changes in central retinal venular equivalent (Δ -0.163±7.94 µm). Children with narrower CRAE at baseline developed higher systolic BP after four years (β [95% CI] 0.78 [0.170-1.398] mm Hg per 10 µm decrease, P=0.012). Children with increased systolic or diastolic BP at baseline developed narrower CRAE (β [95% CI] -0.154 [-0.294 to -0.014] µm per 1mmHg, P=0.031 and β [95% CI] -0.02 [-0.344 to -0.057] µm per 1 mmHg, P=0.006, respectively) at follow-up. Narrowing of retinal arterioles predicted evolution of systolic BP. In turn, higher initial systolic and diastolic BP was associated with subsequent development of microvascular impairments. Our results give good evidence for a bivariate temporal relationship between BP and microvascular health in children. [ABSTRACT FROM AUTHOR]

Aging of the human retina is accompanied by oxidative stress that exerts profound changes in the retinal neurons. It is unknown if oxidative stress influences the cellular components of the retinal vessels in some ways. We examined changes in retinal vessels in human donor eyes (age: 35–94 years; N = 18) by light and transmission electron microscopy, TUNEL and immunohistochemistry for biomarkers of vascular smooth muscle cells (SMC; actin), oxidative stress (4-hydroxy 2-nonenal [HNE] and nitrotyrosine), microglia (Iba-1) and vessels (isolectin B 4). The earliest changes in the endothelium and pericytes of capillaries are apparent from the seventh decade. With aging, there is clear loss of organelles and cytoplasmic filaments, and a progressive thickening of the endothelial and pericyte basal lamina. Loss of filaments, accumulation of lipofuscin and autophagic vacuoles are significant events in aging pericytes and SMC. Actin immunolabelling reveals discontinuity in arterial SMC layers during eighth decade, indicating partial degeneration of SMC. This is followed by hyalinization, with degeneration of the endothelium and SMC in arteries and arterioles of the nerve fibre layer (NFL) and ganglion cell layer in ninth decade. Iba-1 positive microglia were in close contact with the damaged vessels in inner retina, and their cytoplasm was rich in lysosomes. HNE immunoreactivity, but not of nitrotyrosine, was detected in aged vessels from seventh decade onwards, suggesting that lipid peroxidation is a major problem of aged vessels. However, TUNEL positivity seen during this period was limited to few arteries and venules of NFL. This study shows prominent age-related alterations of the pericytes and SMC of retinal vessels. These changes may limit the energy supply to the neurons and be responsible for age-related loss of neurons of the inner retina. [ABSTRACT FROM AUTHOR]

Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cardiovascular disease often develops during childhood, but the determinants of vascular health and disease in young children remain unclear. The study aimed to investigate the association of obesity and hypertension, as well as physical fitness with retinal microvascular health and large artery stiffness, in children. In this cross-sectional study, 1171 primary school children (aged 7.2±0.4 years) were screened for central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) diameters, pulse wave velocity (PWV), body mass index, blood pressure (BP), and cardiorespiratory fitness by standardized procedures for children. BP was categorized according to the reference values of the population-based German KiGGS study (Kinder- und Jugendgesundheitssurvey [Children- and Adolescents Health Survey]) and the American Academy of Pediatrics guidelines. Overweight (mean [95% CI]: CRAE, 200.5 [197.9-203.2] µm; CRVE, 231.4 [228.6-234.2] µm; PWV, 4.46 [4.41-4.52] m/s) and obese children (CRAE, 200.5 [196.4-204.7] µm; CRVE, 233.3 [229.0-237.7] µm; PWV, 4.51 [4.43-4.60] m/s) had narrower CRAE, wider CRVE, and higher PWV compared with normal-weight children (CRAE: 203.3 [202.5-204.1] µm, P<0.001; CRVE: 230.1 [229.1-230.9] µm, P=0.07; PWV: 4.33 [4.31-4.35] m/s, P<0.001). Children with high-normal BP (CRAE, 202.5 [200.0-205.0] µm; PWV, 4.44 [4.39-4.49] m/s) and BP in the hypertensive range (CRAE, 198.8 [196.7-201.0] µm; PWV, 4.56 [4.51-4.60] m/s) showed narrower CRAE, as well as higher PWV, compared with normotensive peers (CRAE: 203.7 [202.9-204.6] µm, P<0.001; PWV: 4.30 [4.28-4.32] m/s, P<0.001). With each unit increase of body mass index and systolic BP, CRAE decreased and PWV increased significantly. Children with the highest cardiorespiratory fitness had wider CRAE, narrower CRVE, and lower PWV compared with least fit children. Childhood obesity and hypertension, even at preclinical stages, are associated with microvascular and macrovascular impairments in young children. Primary prevention programs targeting physical activity behavior may have the potential to counteract development of small and large vessel disease early in life. Clinical Trial Registration- URL: http://www.clinicaltrials.gov . Unique identifier: NCT02853747. [ABSTRACT FROM AUTHOR]

Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: To determine the predictive value of retinal microvascular abnormalities for cerebrovascular ischemic diseases (CVDs), we aimed to investigate the quantitative association between retinal microvascular changes and CVD subcategories: white matter hyperintensities (WMHIs), lacunar infarcts (LIs), and cerebral infarctions (CIs).Methods: Using Meta-analyses Of Observational Studies in Epidemiology guidelines, we searched 6 databases through September 2016 for studies evaluating the linkage between retinal microvascular abnormalities and WMHI, and LI and CI. Studies were included if they reported odds ratios (ORs) and 95% confidence intervals or raw patient level data (that were computed into ORs). Unadjusted and vascular risk-factor adjusted ORs were pooled into meta-analysis using DerSimonian Laird random effects model. Study quality and dissemination biases were assessed and integrated.Results: From 24,444 search-identified records, 28 prospective studies encompassing 56,379 patients were eligible for the meta-analysis. After vascular risk-factor adjustment, focal arteriolar narrowing was associated with WMHI (OR, 1.24 [1.01-1.79]), LI (OR, 1.77 [1.14-2.74]), and CI (OR, 1.75 [1.14-2.69]). Venular dilation was associated with LI (OR, 1.46 [1.10-1.93]), and retinal hemorrhages with WMHI (OR, 2.23 [1.34-3.70]). Any retinopathy exhibited significant association with CI (OR, 1.96 [1.65-2.50]). Heterogeneity was significant (I2>50%) for all syntheses except retinal hemorrhages and WMHI, and retinopathy and CI (I2=0 ⋅ 0%). Associations remained significant after adjustments for quality and publication bias.Conclusions: We found the most significant association between retinal hemorrhages and WMHI. Focal arteriolar narrowing and retinopathy predicted CVD subtypes after risk-factor adjustment, suggesting that features different than traditional vascular risk factors, are involved in CVD pathophysiology. [ABSTRACT FROM AUTHOR]

Objective: To identify the characteristics of retinal vessels that are associated with recurrent cerebral infarction and to establish predictive model for recurrent cerebral infarction in further study.Methods: Up to 196 patients with cerebral infarction were included in our study, including 137 patients with new onset cerebral infarction and 59 patients with recurrent cerebral infarction. Retinal vessel characteristics of all patients were analyzed and reported by an automated retinal image analysis system. Retinal and clinical characteristics were compared between recurrent and new onset subjects. Multivariate logistic regression was used to identify risk factors associated with recurrent ischemic stroke within the year after an initial stroke onset.Results: Every unit increase in the vessel caliber measures of central retinal artery and vein equivalent was found to give coronary heart diseases an additional 4.28 times (95% confidence interval 1.204-15.215) the risk of stroke recurrent whereas every increased unit of arterial and venous angles would be associated with 3.9 and 13.7 times increase in such risk among atrial fibrillation subjects. Measures such as bifurcation coefficient of arterioles showed opposite effects when interacted with different clinical factors. Negative integrations were found between venous asymmetry index and various factors such as atrial fibrillation (odds ratio .73, 95% confidence interval .61-.88), coronary heart diseases (odds ratio .79, 95% confidence interval .70-.89), and bifurcation coefficient of arterioles (odds ratio .38, 95% confidence interval .21-.72), indicating a decreased recurrent risk among these subjects when venous asymmetry level increases.Conclusions: Retinal vessel characteristics interacted with each other as well as traditional clinical risk factors in affecting the risk of stroke recurrence. [ABSTRACT FROM AUTHOR]

Background and aims The relationship between dairy food consumption and dietary calcium intake, and vascular risk factors during adolescence remains unclear. We aimed to prospectively assess whether dairy food consumption (milk, cheese, yoghurt) is associated with blood pressure (BP) and retinal microvascular signs among adolescents. Methods and results As many as 2353 and 1216 participants aged 12 and 17, respectively, were examined. Longitudinal analyses involved 888 subjects with complete baseline and follow-up data. Dairy consumption was assessed from validated semi-quantitative food frequency questionnaires. BP information was collected and retinal vessel caliber was quantified from digital photographs using computer software. In girls, after multivariable adjustment, each serve/day increase in total dairy intake was concurrently associated with 1.04 ( p = 0.03) and 1.10 mm Hg ( p = 0.02) decreases in mean diastolic and arterial BP, respectively. Also in girls, each serve/day increase in cheese intake over 5 years was concurrently related to 7.18 ( p = 0.001), 5.28 ( p = 0.002) and 5.79 mm Hg ( p = 0.001) decrease in mean systolic, diastolic and arterial BP, respectively. Among girls, each 100 mg/day increase in dietary calcium intake was associated with a concurrent 0.5 ( p = 0.01) and 0.3 mm Hg ( p = 0.02) decrease in mean systolic and arterial BP, respectively. Cross-sectionally, adolescents in the highest versus lowest tertile of yoghurt intake had ∼1.3 μm wider retinal arterioles ( p = 0.05) and ∼2.0 μm narrower venules ( p = 0.04). Conclusions Consumption of dairy products, particularly cheese, could have a beneficial effect on BP, particularly among girls. [ABSTRACT FROM AUTHOR]

Copyright of Zentralblatt fuer Arbeitsmedizin, Arbeitsschutz und Ergonomie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wall-to-lumen ratio of retinal arterioles might serve as an in vivo parameter of vascular damage. We analyzed the impact of brachial clinic blood pressure (BP), of central BP, and of 24-hour BP on wall-to-lumen ratio (WLR) of retinal arterioles. In 295 subjects (147 men; age range, 22-72 years; mean age, 54±7 years), WLR of retinal arterioles was assessed in vivo using scanning laser Doppler flowmetry. In addition, clinic and 24-hour BP values were measured. Central hemodynamics was assessed by pulse wave analysis. In treated patients with essential hypertension (n=100), a higher WLR (0.29±0.18 versus 0.23±0.13; P=0.009) was observed in comparison with normotensive individuals (n=119); no significant differences were observed between treated and untreated hypertensive patients (0.29±0.18 versus 0.28±0.18; P=0.7). WLR of retinal arterioles was significantly related to clinic systolic (r=0.18; P=0.002) and pulse pressure (r=0.20; P=0.001), to 24-hour systolic (r=0.25; P=0.0001) and pulse pressure (r=0.17; P=0.005), and to central systolic (r=0.16; P=0.006) and pulse pressure (r=0.18; P=0.002). Multiple regression analysis revealed that only mean systolic 24-hour BP was independently associated with an increased WLR of retinal arterioles. In this large group of hypertensive patients and normotensive individuals, 24-hour systolic BP seems to be the strongest determinant of increased WLR of retinal arterioles. [ABSTRACT FROM AUTHOR]

Background and objective: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary arteriolar small-vessel disease caused by Notch3 mutations. A detailed definition of the neuro-ophthalmologic spectrum of CADASIL might provide new insights in the pathophysiology of small-vessel diseases. Therefore, this study aims to precisely delineate the features and the prevalence of the visual system impairment in CADASIL. Methods: A cohort of 34 genetically confirmed CADASIL patients was enrolled in an observational cross-sectional study. Subjects underwent a complete neuro-ophthalmological evaluation. Clinical features and common cardiovascular risk factors were also considered. Data were compared with those already reported in previous studies. Results: Both afferent and efferent visual structures were commonly impaired in CADASIL patients. Retinal microvascular changes such as arteriolar narrowing and arteriovenous nicking, described in most patients and detected also in asymptomatic carriers, reflect the typical hemodynamic changes of CADASIL. However, less frequent findings, like early macular and lens changes, would indicate a possible further role played by susceptibility to premature aging and degeneration. Cotton wool spots and vessel occlusions were not common. Finally, eye movement abnormalities suggest that the brainstem is particularly vulnerable to damage in CADASIL. Conclusions: Although no specific or prominent neuro-ophthalmologic finding can be considered as hallmark of the disease, afferent and efferent visual system abnormalities could be accounted as complementary markers to study cerebral small-vessel diseases. [Copyright &y& Elsevier]

Cerebral small-vessel disease is thought to contribute to brain atrophy, but it remains unclear whether it affects the gray matter and white matter atrophy differentially. Retinal vessels pro-vide a direct measure to study cerebral small-vessel disease in vivo. In a cohort of 1065 persons (mean age, 67.5 y and 51% women), from the population-based Rotterdam Study, we investigated how retinal vascular calibers relate to brain atrophy and to gray matter and white matter atrophy separately. Retinal arteriolar and venular calibers were semiautomatically measured on digitized fundus transparencies. Using automated quantification of MRI scans, we obtained whole-brain volume and volumes of gray matter and white matter. Both narrower arteriolar and wider venular calibers were associated with smaller brain volume, independent from each other. These associa-tions were primarily driven by smaller white matter volume, whereas no associations were seen for gray matter volume. Adjustments for cardiovascular risk factors attenuated the results, but wider venular caliber remained borderline significantly associated with smaller white matter volume. Our data provide evidence that cerebral small-vessel disease contributes to brain atrophy primarily by affecting the cerebral white matter. [ABSTRACT FROM AUTHOR]

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Summary: ADAM17 (a disintegrin and metallopeptidase domain 17) is crucial for eye morphogenesis. In this study we analysed the expression pattern of ADAM17 during mouse eye development. ADAM17 expression in adult retina was examined using the reverse transcription-polymerase chain reaction (RT-PCR) and verification of the RT-PCR products by DNA sequencing. Immunohistochemistry was performed to evaluate the ADAM17 expression pattern in mouse eyes at developmental stages of embryonic day (E) 12, E14, E16, E18, postnatal day (P) 0, P1, P4, P7, P14, P 30 and P175 (adult). We detected ADAM17 mRNA in adult retina tissue. ADAM17 protein was expressed in non-pigmented ciliary epithelial cells and in retinal vessels from P7 onwards during eye development. In corneal epithelial cells and endothelium, ADAM17 protein was present from P14 onwards. Although, mice in which the functional ADAM17 gene is significantly reduced develop multiple eye malformations, the expression of ADAM17 is not ubiquitous over the entire eye. Its expression pattern during development suggests that not only TNF-alpha but additional membrane-anchored substrates of ADAM17 play an important role in eye formation. [Copyright &y& Elsevier]

The article discusses the microangiopathic changes in retinal vessels that comprise of traditional risk factors including the eye blindness diseases, the cerebrovascular risk factors and the systemic diseases such as metabolic syndrome, arterial hypertension and stroke.

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Abstract: Objective: To investigate the association of retinal vascular calibers with hyperuricemia in a middle-aged and elderly population. Methods: A cross-sectional design was applied in this study and 869 participants aged =40 years from a high-risk group for diabetes were recruited. All participants received the anthropometrical measurements and laboratory tests. Retinal arteriolar and venular caliber of the participants were measured with a semi-automated system. Hyperuricemia was defined as a serum uric acid level >420 μmol/L in men and >360 μmol/L in women. Linear regression models were used to assess the association of hyperuricemia with retinal vascular calibers. These models were additionally adjusted for age, central obesity, hypertension, dyslipidemia, weekly activity, smoking status, and education. Results: Among the 869 participants, 133 (15.3%) suffered from hyperuricemia. The crude mean serum uric acid level was 312.3 μmol/L (Standard Deviation 79.5); mean concentration was 355.0 μmol/L (SD 75.5) in male participants, and 288.0 μmol/L (SD 71.1) in female participants (age-adjusted difference 58.1 μmol/L, 95% Confidence Internal 48.5, 67.6). After adjusting for additional covariates, male participants with hyperuricemia had 3.77 μm (95% CI −0.46, 8.00) smaller arteriolar caliber and 6.20 μm (95% CI 0.36, 12.04) larger venule than those without hyperuricemia; the corresponding numbers among female participants were 1.57 μm (95% CI −1.07, 4.21) for retinal arteriolar caliber and 2.28 μm (95% CI −1.72, 6.27) for retinal venular caliber. Conclusion: Hyperuricemia was associated with smaller retinal arteriolar caliber and larger venular caliber mainly in male participants in this study. [Copyright &y& Elsevier]

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Copyright of Arquivos Brasileiros de Oftalmologia is the property of Arquivos Brasileiros de Oftalmologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• In patients with severe COVID-19, there are changes in thickness of the choroid and retinal vessel walls. • These changes occur particularly in the vessel walls and are thought to be due to endothelitis. • Reversible inflammation affecting all systems can be demonstrated in retinal vessels, the window of the vascular system. : To compare the differences in retinal vascular structure and choroidal thickness between the active disease and post-recovery periods in COVID-19 patients and healthy controls. : This prospective, cross-sectional study included 30 eyes from 30 patients with severe COVID-19 and 30 eyes of 30 sex-matched healthy controls. Central macular thickness (CMT), subfoveal choroidal thickness (CT) and retinal vascular changes of patients were measured after positive polymerase chain reaction (PCR) (where the patient had COVID-19-related symptoms) and then three months after two negative PCRs. Laboratory parameters, including C-reactive protein and d -dimer levels, were also recorded. : The mean age of the patients was 47.90 ± 9.06 years in patients group, 49.07 ± 8.41 years in control goups (p = 0.467). In terms of choroidal thicknesses subfoveal, nasal and temporal region were significantly higher in the active disease period than control group (p = 0.019, p = 0.036, p = 0.003, respectively). When the after recovery period was compared with the control group in terms of choroidal thickness, although the choroidal thickness was higher in all regions, this difference was not found statistically significant. There was no statistically significant difference in CMT between groups (p = 0.506).The mean venous and arterial wall thicknesses were significantly higher in the active period than after recovery (p = 0.023, p = 0.013, respectively) but there were no differences between after recovery and control groups in the pairwise comparison (p = 0.851, p = 0.715, respectively). : In patients with severe COVID-19, there are changes in thickness of the choroid and retinal vessel walls. While vascular wall thickness increases due to inflammation, the absence of lumen changes may be associated with hemodynamic variables. [ABSTRACT FROM AUTHOR]

• Small and large vessels are detected separately based on their unique characteristics. • A directional triple-stick filtering are used to boost the detection of tiny vessels. • BM3D filter is used to enhance specificity of the multi-scale line detection approach. • Boundary compensation and morphological opening are used as key post processing steps. Vessel local characteristics such as noise, illumination, and direction vary significantly in a fundus image, making it difficult to segment the vessel tree structure as a whole. To facilitate vessel detection, an alternative procedure proposed here, whereby retinal vessels first classified into two categories, large and small. Then, for its unique characteristics, each group has been processed with its own enhancement and detection filter. The sensitivity of the proposed method is boosted by capturing tiny vessels through a directional filter bank followed by its associated triple-stick filtering. Additionally, the specificity of the proposed method is enhanced through noise suppression attributed largely to the proposed BM3D filtering and multi-scale line detection approach. As a result, the detection accuracy on the DRIVE, STARE, and CHASE DB1 datasets is significantly improved, with scores of 0.9610, 0.9586, and 0.9578, respectively. [ABSTRACT FROM AUTHOR]

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• Although the intravitreal anti-VEGF treatments have been demonstrated to be beneficial in the treatment of DME, the physiologic functions of VEGF (such as increased production of nitric oxide (NO), a well-known vasodilator) may also be restricted, causing unwanted effects that could disrupt the regulation of retinal vessel diameters and blood flow in addition to other functions. • The vasoconstrictor effect of intravitreal anti-VEGF treatments on the retinal vessels could primarily lead to ocular blood flow disruption, so we hypothesized that the retinal vessels diameters might be altered after these treatments. • This study aims to compare retinal vessel diameter changes after administering three consecutive monthly loading doses of two different intravitreal anti-VEGF agents in patients with DME. To evaluate and compare the effects of intravitreal ranibizumab and aflibercept treatment on retinal vessel diameters in patients with diabetic macular edema (DME). Thirty initial-treatment naïve patients with DME who received three loading doses at monthly intervals of intravitreal ranibizumab or aflibercept were retrospectively reviewed. The diameters of the central retinal artery and vein sections at a distance of 1500 microns from the optical disc boundary were measured and evaluated at baseline and after the first, second, and third month of the treatment, using infrared images from optical coherence tomography (OCT) (Heidelberg Engineering, Heidelberg, Germany). In the superotemporal artery (STA) measurements, the mean basal vessel diameter decreased from 110.00 ± 17.25 μm to 102.60 ± 16.90 μm (p = 0.001) in the third month of the treatment in the ranibizumab group. In the aflibercept group, measurements of the basal STA vessel diameter decreased from 110.20 ± 21.25 μm to 103.93 ± 19.03 μm (p = 0.001) at the third month. The mean basal inferotemporal artery (ITA) vessel diameter was significantly decreased at the third month in both ranibizumab (p = 0.001) and aflibercept groups (p = 0.005). In the superotemporal vein (STV) and inferotemporal vein (ITV) measurements, vessel diameters were found significantly decreased at the end of the third month compared with basal measurements in both the ranibizumab (p = 0.001; p = 0.001, respectively) and aflibercept (p = 0.001; p = 0.004, respectively) treatment groups. The retinal vessel measurements were not found to differ significantly between the two intravitreal treatment agents (p > 0.05). Both intravitreal ranibizumab and aflibercept agents cause a significant narrowing in the retinal vessel diameters in patients with DME after three loading doses at monthly intervals. [ABSTRACT FROM AUTHOR]

• COVID-19, lead to vasculopathy and retinal vascular pathologies. • The ability of OCTA to provide vascular mapping of separate layers is an important advantage. • Very limited report is available about superficial and deep capillary plexus in patients with COVID 19 disease. • Vascular densities of both superficial and deep capillary network are affected in COVID 19 disease. • Foveal avascular zone is not affected in patients who have recovered from mild to moderate COVID-19 disease. The purpose is to evaluate macular vascular densities (VDs) using optical coherence tomography angiography (OCTA) in patients effected by coronavirus disease-2019 (COVID-19). The superficial (SF) and deep macular VD of 50 patients with SARS CoV2 pneumonia who had positive polymerase chain reaction (PCR) tests and who recovered after receiving treatment and 55 healthy age- and gender-matched controls were compared using OCTA. Blood inflammation parameters were also recorded. There was no statistically significant difference between the two groups in terms of age and gender (p = 0.147 and p = 0.504, respectively). Nor was there a difference with respect to smokers between the two groups (p = 0.231). In COVID-19 patients, the VDs in superior hemi quadrant, superior quadrant and inferior quadrant, were significantly lower (p = 0.033, p = 0.029 and p = 0.042, respectively) in superficial plexus. It was also significantly lower in parafovea, superior hemi and superior quadrants (p = 0.026, p < 0.001 and p = 0.004, respectively) in deep plexus. In addition, white blood cell and neutrophil counts were significantly negatively correlated with the VD of the deep parafovea, deep superior quadrant and deep superior hemi quadrant (p < 0.05). There was no difference between the patient and control groups in both superficial and deep foveal avascular zone (FAZ) (p = 0.101 and p = 0.691 respectively). In COVID-19 disease, VD is low in some sectors in both SF and deep layers, but no change in FAZ. The effect of COVID 19 disease on the retina and whether it makes the retina sensitive to damage can only be understood with long-term follow-up. [ABSTRACT FROM AUTHOR]

Retinal Vessels segmentation is an important procedure for detecting and diagnosing a variety of pathological diseases. However, the inherent complex properties around the disc make it challenging to improve the segmenting accuracy of capillaries and the retinal blood vessels at the ends. In this paper, we proposed a multi-scale channel importance sorting and important spatial information positioning (MSCS) encoder–decoder for segmentation in Retinal Vessels. Firstly, the fully convolutional encoder–decoder is formed to implement a series of linear and non-linear transformation and achieve end-to-end segmentation tasks. Then, the channel importance sorting module is employed to suppress useless feature responses during the process of encoding and to identify effective channels, whose information is utilized to recognize capillaries and the retinal vessels at the ends. Finally, in the decoding stage, the spatial attention mechanism module is designed to extract the positioning information of multi-scale feature maps. The spatial information of retinal vessels is collected to better locate the position of the vessels. In addition, aiming at taking fully advantage of the network, the multi-scale asymmetric cascade convolution module is proposed to reduce the parameters of the model and increase the operation rate. Experimental results on DRIVE, STARE datasets indicate that the proposed method outperforms other state-of-the-art strategies. This system, as demonstrated, can greatly decrease false positive rate of the blood vessels at the ends and enhance the sharpness of retinal vessels. • Fully convolutional encoder-decoder enhances the global correlation between pixels. • Multi-scale cascaded convolution modules promote the computationally of network. • Channel importance sorting module improves the segmenting accuracy of capillaries. • Spatial attention mechanism enhances the sharpness of retinal vessels. [ABSTRACT FROM AUTHOR]

Objective The branching pattern of retinal vessels may be affected in Behçet’s Disease (BD). Fractal analysis can be used as a new method to quantify the changes of the vascular branching pattern. In this study, we examined, for the first time, the relationship between retinal fractal dimension ( D f ) and retinal vascular changes seen in patients with BD. Methods We conducted a retrospective study of 10 new cases of BD with clinically ocular involvement. Color fundus images taken from both eyes of the participants have been analyzed, and D f of the whole retinal vasculature was quantified using a novel computer-based program. The resultant D f was compared with that of healthy individuals. Results The mean D f , calculated from 20 fundus images of cases with BD, was 1.59 ± 0.064. It was lower than that of healthy participants (1.65 ± 0.060) significantly ( P = 0.013). Conclusion Retinal fractal analysis of cases with BD has been performed for the first time, and the results showed that early retinal vascular changes seen in new cases of BD are associated with lower retinal D f . Retinal fractal analysis in BD can be practically utilized as a potential tool for screening of retinal involvement, evaluating the prognosis and the response to treatment. [ABSTRACT FROM AUTHOR]

The article presents the case of a man with cold hemagglutinin disease and no referred visual symptoms. A routine optometrist examination found the man to have scattered retinal hemorrhages, abnormal retinal vasculature resembling neovascularization and aggregated flowing of material in the retinal vessels. There has been no published material describing retinopathy related to cold hemagglutinin disease and it is suggested that the abnormalities derive from retinal ischemia areas that result in the development of a type of collateral circulation.