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Background: Cerebral microvascular dysfunction is a promising area for research into the pathogenesis of major depressive disorder (MDD) and bipolar disorder (BD). Despite the scientific and clinical potential of studying microvascular dysfunction, progress in this area has long been hampered by the lack of methods to study microvessels intravitally., Aims: The aim of the present study was to search for potential optical coherence tomography (OCT) and OCT-angiography (OCTA) biomarkers of BD and MDD., Methods: One hundred and five consecutive patients with a current depressive episode were enrolled in the study (39 - BD and 66 - MDD). In addition, forty-one generally healthy subjects were enrolled as a control group. Only the right eye was examined in all subjects. Structural OCT and OCTA scans with signal strength ≥7 were included., Results: Structural OCT measurements showed no significant differences between the groups. OCTA measurements of foveal avascular zone (FAZ), area and skeleton density showed a decrease in the retinal capillary bed in BD patients, whereas OCTA values in MDD patients did not differ from the control group. Several significant differences were found between the BD and control groups. In the BD group, the FAZ of the deep capillary plexus was increased, reflecting a reduction in capillary perfusion in the central subfield of this plexus., Conclusions: OCTA measurements of FAZ, area and skeleton density showed a decrease in the retinal capillary bed in BD patients, whereas OCTA values in MDD patients did not differ from the control group., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could appear to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Purpose: This study is to investigate the relationship between long-term changes in the foveal avascular zone (FAZ) and visual function of eyes with macular hole (MH) and compare the relationship between the FAZ of MH eyes and fellow eyes., Methods: This study included 31 patients with unilateral MH who underwent vitrectomy and their fellow eyes. Best-corrected visual acuity (BCVA) and metamorphopsia were measured preoperatively and at 1, 3, 6, and 12 months postoperatively. We evaluated retinal parameters using optical coherence tomography (OCT) and the superficial FAZ using OCT angiography. The FAZ ratio was defined as follows: (preoperative FAZ area of the MH eye)/(FAZ area of the fellow eye)., Results: The preoperative FAZ area of MH eyes was 0.42 ± 0.08 mm 2 , which decreased to 0.24 ± 0.07 mm 2 1 month postoperatively (p < 0.001) and slightly increased to 0.25 ± 0.06 mm 2 12 months postoperatively (p = 1.000). The FAZ area did not differ significantly from that of fellow eyes (0.39 ± 0.06 mm 2 , p = 0.281). The FAZ area of MH eyes was not associated with visual function at any time point. The FAZ ratio showed a correlation with the preoperative, 6-month, and 12-month BCVA (r = 0.604, p < 0.001; r = 0.510, p = 0.003; and r = 0.475, p = 0.007, respectively)., Conclusions: A larger FAZ in the MH eye than that in the fellow eye is associated with poorer long-term visual acuity. The preoperative comparison of the FAZ of the MH eye with that of the fellow eye may be a biomarker for predicting long-term visual acuity., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Migraine, classified as a neurovascular disease, has been identified as a potential risk factor for ocular vascular complications. Our study aimed to compare retinal vessel density and perfusion density between subjects with migraine and healthy subjects using optical coherence tomography angiography (OCTA). In this cross-sectional case-control study, we enrolled 30 migraine subjects with aura (MWA), 30 migraine subjects without aura (MWOA) and 30 age and gender-matched healthy controls (HC). The foveal avascular zone (FAZ) in superficial capillary plexus (SCP), Vessel density (VD) and perfusion density (PD) in SCP and deep capillary plexus (DCP) were assessed in a 3 × 3 mm scan of the macula with the swept source OCT. Results indicated that the FAZ of MWA and MWOA subjects was significantly larger from HC. Also, FAZ of MWA was larger from MWOA. VD and PD in both SCP and DCP were significantly reduced in both MWA and MWOA groups compared to HC. However, VD and PD did not show significant differences among MWA and MWOA. Additionally, the duration of disease was the main determinant of the FAZ. In conclusion, the FAZ in the SCP, VD and PD in the SCP and DCP of the macula were affected in both MWA and MWOA. FAZ, specifically, was increased with the evolution of the disease. These findings might contribute to an increased risk of ocular vascular complications among subjects with migraine and could potentially use OCTA as a biomarker for this population., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background/aims: To investigate the association between longitudinal changes of foveal avascular zone (FAZ) area and the rate of structural and functional progression in glaucoma., Methods: A longitudinal cohort included 115 eyes (46 glaucoma suspect and 66 primary open-angle glaucoma) of 81 patients having ≥2 year follow-up, and ≥4 visits with optical coherence tomography angiography and visual field (VF). Eyes in the longitudinal cohort with a slope greater than that found in 95 percentile of separate healthy test-retest series for FAZ area were categorised into FAZ progressors; all other eyes were defined as FAZ non-progressors. A generalised linear mixed-effect model was used to investigate the association of FAZ progressors with demographic and clinical characteristics., Results: Faster ganglion cell complex (GCC) thinning and faster VF mean deviation (MD) loss were found in eyes with FAZ progressors compared with FAZ non-progressors (mean difference: -0.7 (95% CI, -1.4 to -0.1) µm/y; p=0.026, -0.3 (-0.5 to -0.1) dB/y; p=0.017, respectively), while whole image vessel density was not associated with FAZ progressors (p=0.929). SD of intraocular pressure (IOP) and IOP range were also associated with FAZ progressors in separate multivariable models (OR: 1.54 (1.02 to 2.32) per 1 mm Hg higher, p=0.041; OR: 1.20 (1.01 to 1.41) per 1 mm Hg higher; p=0.035, respectively)., Conclusions: Significant FAZ increase was weakly associated with moderately faster rates of both GCC thinning and VF MD loss, but not macular vessel density change in glaucoma eyes. Additional studies are needed to elucidate the pathophysiological associations between macula GCC thinning and FAZ area increases in glaucoma., Competing Interests: Competing interests: TN: consultant—Topcon; SM: consultant—Topcon; EW: none; GG: none; J-HW: none; AK: Fight for sight, LMZ: consultant—Topcon, Abbvie; financial support—Carl Zeiss Meditec, Heidelberg Engineering, OptoVue. Patent: AISight Health (co-founder), RNW: consultant—Abbvie, Aerie Pharmaceuticals, Allergan, Amydis, Editas, Equinox, Eyenovia, Iantrek, IOPtic, Implandata, iSTAR Medical, Nicox, Santen, Tenpoint and Topcon; financial support—Heidelberg Engineering, Carl Zeiss Meditec, Optovue, Centervue, Zilia and Topcon., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To investigate the preoperative choriocapillaris perfusion (CCP) as a biomarker in patients with idiopathic epiretinal membrane (iERM)., Materials and Methods: 28 patients (28 eyes) with unilateral iERM who received pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling were included for retrospective observational study. Optical coherence tomography (OCT) and angiography (OCTA) was performed before and after PPV. Area, perimeter, and circularity of superficial foveal avascular zone (FAZ) were analyzed preoperatively in both eyes using OCTA. Preoperative CCP was also analyzed with binarized en-face OCTA images. Measurements of best-corrected visual acuity (BCVA) and central foveal thickness (CFT) by OCT were conducted at the baseline and 6 months following the surgery. The correlations of preoperative OCT parameters with postoperative BCVA and CFT reduction were analyzed., Results: CCP was significantly lower (p < 0.001) and FAZ had shrunk (p < 0.001) in eyes with iERM compared to unaffected fellow eyes before surgery. BCVA and CFT became significantly improved after surgery (p = 0.001, p < 0.001). Multiple regression analysis revealed that preoperative CCP was significantly related with BCVA improvement (β = 0.185, p = 0.005), postoperative BCVA (β = 0.108, p = 0.023) and ratio of post- to preoperative CFT (β = 0.106, p = 0.044)., Conclusions: Preoperative CCP is a biomarker for poor functional and anatomical prognosis after surgery in iERM., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Kim et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Purpose: To explore the characteristics of macular structure, microcirculation, and foveal avascular zone (FAZ) morphology in pathological myopia and to research the associations between these factors and pathological myopia., Methods: This is a cross-sectional study. The study included 103 eyes with non-high myopia and 206 eyes with high myopia (139 with simple high myopia and 67 with pathological myopia). Macular structural and microcirculation parameters were determined using optical coherence tomography angiography (OCTA). The FAZ morphological parameters were measured manually using Image J software. Correlations between pathological myopia and various factors were analyzed., Results: Patients with pathological myopia had a thinner retinal thickness (RT) and choroidal thickness (CT) and a lower retinal superficial vascular density (SVD), retinal deep vascular complex density (DVD), choriocapillaris perfusion area (CCPA), and choroidal vascularity index (CVI) (all P < 0.05). Patients with pathological myopia had a larger FAZ area, perimeter, major axis, minor axis, acircularity index (AI), and lower circularity index (CI) (all P < 0.01). The axial length (AL), the major axis of the superficial FAZ, CI, and AI were significantly correlated with myopia severity (all P < 0.05)., Conclusions: Patients with pathological myopia exhibited worse macular microcirculation and thinner macular retina and choroid. The FAZ in pathological myopia was larger and more irregular. The AL, CI, and AI were significantly associated with myopia severity. Thus, CI and AI might serve as new indicators for monitoring the progression of myopia. Further investigations should be performed., Trial Registration: Clinical Trials.gov Identifier: ChiCTR2100046590., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To investigate changes in foveal avascular zone parameters in individuals with prediabetes compared to normoglycemic controls. PUBMED, Scopus and Cochrane Library were searched for published articles comparing the foveal avascular zone between prediabetic individuals and normoglycemic controls as assessed by optical coherence tomography angiography (OCTA). Standardised Mean Difference (SMD) with 95% confidence interval (CI) was computed for the comparison. A total of seven studies were included in our analysis, 6 provided data for the superficial capillary plexus from 345 eyes of individuals with prediabetes and 347 eyes of controls and 4 provided data on the deep capillary plexus from 285 eyes from individuals with prediabetes and 325 eyes of controls. Foveal avascular zone (FAZ) area in the superficial capillary plexus was enlarged in individuals with prediabetes compared to normoglycemic controls (SMD = 0.23, 95% CI = 0.03-0.44, p = 0.03, I 2  = 27%, 6 studies). There was no statistically significant change in the deep capillary plexus FAZ area between the two groups (SMD = 1.14, 95% CI = -0.06-2.34, p = 0.06, I 2  = 97%, 4 studies). FAZ area in the superficial capillary plexus was larger in individuals diagnosed with prediabetes compared to normoglycemic controls. This finding suggests that prediabetes could induce retinal microvascular changes before the onset of clinical diabetes. More original studies are needed to validate the results of the current meta-analysis., (© 2024. The Author(s), under exclusive licence to The Royal College of Ophthalmologists.)

Purpose: In aging and early-intermediate age-related macular degeneration (AMD), rod-mediated dark adaptation (RMDA) slows more at 5° superior than at 12°. Using optical coherence tomography angiography (OCTA), we asked whether choriocapillaris flow deficits are related to distance from the fovea., Methods: Persons ≥60 years stratified for AMD via the Age-Related Eye Disease Study's nine-step system underwent RMDA testing. Two adjacent 4.4° × 4.4° choriocapillaris OCTA slabs were centered on the fovea and 12° superior. Flow signal deficits (FD%) in concentric arcs (outer radii in mm, 0.5, 1.5, 2.2, 4.0, and 5.0 superior) were correlated with rod intercept time (RIT) and best-corrected visual acuity (BCVA)., Results: In 366 eyes (170 normal, 111 early AMD, 85 intermediate AMD), FD% was significantly worse with greater AMD severity in all regions (overall P < 0.05) and poorest under the fovea (P < 0.0001). In pairwise comparisons, FD% worsened with greater AMD severity (P < 0.05) at distances <2.2 mm. At greater distances, eyes with intermediate, but not early AMD differed from normal eyes. Foveal FD% was more strongly associated with longer RIT at 5° (r = 0.52) than RIT at 12° (r = 0.39) and BCVA (r = 0.21; all P < 0.0001). Choroidal thickness was weakly associated with longer RIT at 5° and 12° (r = 0.10-0.20, P < 0.05) and not associated with AMD severity., Conclusions: Reduced transport across the choriocapillaris-Bruch's membrane-retinal pigment epithelium complex, which contributes to drusen formation under the macula lutea (and fovea), may also reduce retinoid resupply to rods encircling the high-risk area. FD% has potential as a functionally validated imaging biomarker for AMD emergence.

Purpose: To evaluate the findings and the correlation of optical coherence tomography angiography and pattern and flash electroretinography in diabetes mellitus without retinopathy., Methods: Seventy-six eyes of 38 diabetic patients and age- and gender-matched control subjects were included in the study. The foveal avascular zone (FAZ), whole, foveal, parafoveal and perifoveal vascular densities of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillary plexus (CCP) layers were analyzed using optical coherence tomography angiography (OCTA). The amplitudes and implicit times of P50 and N95 waves of the pattern ERG (pERG) and the amplitudes and implicit times of the scotopic and photopic b-waves and oscillatory potentials (OP) of the flash ERG (fERG) tests were evaluated using the Metrovision brand monpack model device., Results: The mean age of the patients was 59.7 ± 7.9 [range 43-79] years. Eighteen (47%) of the patients were female and 20 (53%) were male. The mean duration of diabetes was 7.45 ± 6.2 [range 1-20] years. No significant difference in FAZ area was found between study subjects and controls. Vascular density (VD) values of the superficial capillary plexus (SCP) layer were significantly lower (whole VD, 44.7 ± 3.3 vs. 46.6 ± 3.2%, p  = 0.01, foveal VD 16.8 ± 6.4 vs. 24.9 ± 6.1%, p  < 0.01, parafoveal VD 45.6 ± 4.5 vs. 47.1 ± 4.4%, p  = 0.27 and perifoveal VD 45.5 ± 3.3 vs. 47.3 ± 3.1%, p  = 0.01, respectively) in the diabetic group except the parafoveal area. VD measurements in deep and choriocapillary plexuses did not significantly differ between the groups ( p  > 0.05). ERG tests revealed significantly lower scotopic b-wave amplitudes (130.2 ± 39.3 µV vs.163.3 ± 47.8 µV, p  < 0.01) and photopic b-wave amplitudes (83.2 ± 20.7 µV vs. 99.6 ± 29.4 µV, p  < 0.01) in the diabetic patients. The implicit time of the photopic responses was significantly prolonged (28.9 ± 1.3 ms vs. 27.8 ± 2.1 ms, p  = 0.01) in the patients. Oscillatory potentials in all components consisting of O1 to O4 and the sum of the OP potentials were lower in the diabetic group than the control subjects ( p  < 0.001). The P50 and N95 amplitudes and implicit times were comparable between the groups ( p  > 0.05). Correlation analysis showed a positive correlation between N95 amplitudes in pERG and the superficial vessel densities in OCTA ( r  = 0.26, p  = 0.04). A negative correlation was found between photopic implicit times in fERG and the choriocapillary vessel densities (r=-0.27, p  = 0.03)., Conclusion: OCTA revealed decreased superficial vascular densities with the onset of the metabolic process of diabetes mellitus. As a result of these structural changes, lower scotopic and photopic amplitudes, decreased OP amplitudes, and prolonged implicit times in flash ERG were obtained.

Purpose: The aim of this study is to analyse whether optical coherence tomography angiography (angio-OCT, OCTA) measurements can be a useful tool to differentiate central nervous system (CNS) involvement in rheumatic disorders (RD) from multiple sclerosis (MS)., Methods: A total of 85 patients- 41 with MS, 21 with RD with CNS involvement and 23 healthy controls were included in the study. All individuals underwent OCTA and the following parameters were measured in each eye separately: average foveal and parafoveal vessel density (VD), average foveal and parafoveal vessel length (VL) of the superficial capillary plexus (SCP) and deep capillary plexus (DCP), as well as area, perimeter, and circularity of the foveal avascular zone., Results: OCTA showed a VD reduction in the foveal region of the SCP in eyes of RD patients when compared to MS patients (21.96 ± 3.39 vs.23.88 ± 3.05 (p = 0.003)). There have been no significant differences in any of the assessed parameters that is average VD and total average VL in the foveal area of the SCP as well as of the DCP in the general population comprising healthy controls, MS and RD groups (p > 0.05 for all)., Conclusions: Our results suggest that an OCTA finding of decreased VD in the foveal region of the SCP may be considered as a potentially useful biomarker of RD in comparison with MS patients., (© 2024. The Author(s).)

Purpose: To evaluate microvascular intereye differences in diabetic patients with same-stage diabetic retinopathy (DR) in both eyes as assessed using optical coherence tomography angiography (OCTA)., Methods: In this cross-sectional study, fovea-centered swept-source 6 × 6 mm OCTA scans were acquired using a 200 kHz OCTA device. Vessel density (VD) and fractal dimension were calculated on binarized, vessel-segmented images in the superficial capillary plexus (SCP) and deep capillary plexus (DCP). Foveal avascular zone (FAZ) area (FAZA) and perimeter (FAZP) was measured and FAZ circularity (FAZC) calculated. Absolute difference (δabs) and asymmetry index between eyes was assessed and compared across DR stages. Differences of VD, FD, and FAZ parameters between left and right eye were evaluated using linear mixed models., Results: A total of 336 eyes of 168 diabetic patients without DR and with DR stages ranging from mild nonproliferative to proliferative DR were included for analysis. The intereye comparison revealed significantly lower VD in the SCP (estimate [95% CI] = -0.009 [-0.01; -0.006], P < 0.01), as well as a significantly lower FD in the SCP (-0.007 [-0.009; -0.005], P < 0.01) of the left compared to the right eye. FAZC of the left compared to the right eye was lower in eyes without DR, moderate DR, and PDR (P < 0.05). FAZ δabs and asymmetry index were higher in more advanced disease stages (P < 0.05)., Conclusions: OCTA metrics provide important information on the retinal microvasculature in systemic diseases such as DR. Our results reveal a significant intereye difference with lower VD and FD in the SCP as well as higher FAZ impairment of the left compared to the right eye.

Purpose: To develop Choroidalyzer, an open-source, end-to-end pipeline for segmenting the choroid region, vessels, and fovea, and deriving choroidal thickness, area, and vascular index., Methods: We used 5600 OCT B-scans (233 subjects, six systemic disease cohorts, three device types, two manufacturers). To generate region and vessel ground-truths, we used state-of-the-art automatic methods following manual correction of inaccurate segmentations, with foveal positions manually annotated. We trained a U-Net deep learning model to detect the region, vessels, and fovea to calculate choroid thickness, area, and vascular index in a fovea-centered region of interest. We analyzed segmentation agreement (AUC, Dice) and choroid metrics agreement (Pearson, Spearman, mean absolute error [MAE]) in internal and external test sets. We compared Choroidalyzer to two manual graders on a small subset of external test images and examined cases of high error., Results: Choroidalyzer took 0.299 seconds per image on a standard laptop and achieved excellent region (Dice: internal 0.9789, external 0.9749), very good vessel segmentation performance (Dice: internal 0.8817, external 0.8703), and excellent fovea location prediction (MAE: internal 3.9 pixels, external 3.4 pixels). For thickness, area, and vascular index, Pearson correlations were 0.9754, 0.9815, and 0.8285 (internal)/0.9831, 0.9779, 0.7948 (external), respectively (all P < 0.0001). Choroidalyzer's agreement with graders was comparable to the intergrader agreement across all metrics., Conclusions: Choroidalyzer is an open-source, end-to-end pipeline that accurately segments the choroid and reliably extracts thickness, area, and vascular index. Especially choroidal vessel segmentation is a difficult and subjective task, and fully automatic methods like Choroidalyzer could provide objectivity and standardization.

Purpose: To analyze FAZ superficial (s) and deep (d) area and dimensions by using spectral-domain optical coherence tomography angiography (OCTA) in healthy eyes and to assess effect of age, gender, axial length (AL), central foveal thickness (CFT), and central choroidal thickness (CCT) on FAZ. We aimed to study FAZ dimensions with OCTA in healthy Indian eyes with the purpose of creating a normative database., Settings and Design: Observational cross-sectional study., Methods: In total, 200 healthy eyes in the age group of 20-60 years having best corrected visual acuity better than 6/12 (Snellen's) with no systemic illness/intraocular surgery were included. FAZ parameters were calculated using OCTA, and the same was evaluated for any correlation with different ocular parameters mentioned above. The data were reported as frequencies/percentages and mean ± SD. The association between quantitative variables was evaluated using Pearson's correlation coefficient., Results: The dFAZ area (0.56 ± 0.12 mm 2 ) was larger than the sFAZ area (0.42 ± 0.13 mm 2 ). Females had larger FAZ than males. AL and CFT had a negative correlation, whereas CCT had a positive correlation with FAZ. Age did not influence FAZ. sFAZ and dFAZ varied significantly in healthy eyes., Conclusion: FAZ parameters calculated using OCTA in healthy Indian eyes suggested that the area and dimensions in both SCP and DCP are larger in individuals from the Indian subcontinent when compared to other parts of the world. FAZ area and dimensions, when compared to previous studies, were variable. Thus, there is a need to establish normative data for ethnicity for proper interpretation of FAZ using OCTA., (Copyright © 2024 Copyright: © 2024 Indian Journal of Ophthalmology.)

Significance: An understanding of factors that affect the foveal avascular zone (FAZ) in healthy eyes may aid in the early identification of patients at risk of retinal pathology, thereby allowing better management and preventive measures to be implemented., Purpose: The size and shape of the FAZ can change due to retinal diseases associated with oxidative stress, including diabetic retinopathy, glaucoma, and macular degeneration. This study aimed to assess the relationship, if any, between factors that may affect the superficial FAZ (i.e., vessel density, vessel perfusion, overweight/obesity) and possible links with macular pigment optical density in young, healthy participants., Methods: One hundred thirty-nine participants aged 18 to 35 years were recruited to this cross-sectional study. The superficial FAZ area, foveal vascularity, and central macular thickness (CMT) were assessed using the Cirrus 5000. Health parameters, body mass index, trunk fat %, and macular pigment were analyzed to determine possible associations with the superficial FAZ., Results: Mean FAZ area was 0.23 ± 0.08 mm2. Females had a significantly larger mean FAZ area than males (p=0.002). The FAZ area was positively correlated with body mass index (Pearson's r = 0.189, p=0.026). Significant correlates of the FAZ area in the multivariate model included vessel perfusion (central), CMT, and trunk fat %, collectively explaining 65.1% of the overall variability., Conclusions: Study findings suggest that reduced vessel perfusion, thinner CMT, and higher trunk fat % are plausible predictors of a larger FAZ area in healthy Caucasian adults. Low macular pigment optical density was, however, not associated with increased FAZ size in young healthy eyes. Noninvasive optical coherence tomography angiography testing, in association with these predictors, may aid in the early detection and monitoring of retinal diseases associated with oxidative stress., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest., (Copyright © 2024 American Academy of Optometry.)

Purpose: To evaluate anatomical changes in the low-stage partial attachment-type idiopathic epiretinal membrane (iERM) over 2 years., Methods: Data from patients with low-stage partial attachment-type iERM (stage 2) were analyzed. The main outcome measures were anatomical changes, including changes in the foveal avascular zone (FAZ) area, vessel density (VD) in the vascular plexus, and thickness of retinal sublayers during the follow-up period., Results: Thirty patients (mean age: 68±12 years) were included in the study. The FAZ area on the superficial vascular plexus (SVP) significantly decreased from baseline (0.12±0.08 mm 2 ) to month 24 (0.10±0.08 mm 2 , p=0.024). However, the FAZ area on the deep vascular plexus (DVP) did not significantly decrease from baseline (0.15±0.13 mm 2 ) to month 24 (0.14±0.14 mm 2 , p=0.099). VDs on both the SVP and DVP did not show significant change from baseline (29.51±8.14% vs. 28.35±5.63%) to month 24 (29.79±9.77%, p=0.564 vs. 28.17±5.75%, p=0.417). Parafoveal ganglion cell and inner plexiform layer (GCIPL) thickness decreased from baseline (108.77±13.61 μm) to month 24 (103.03±15.54 μm, p=0.004). The central total retinal layer thickness did not significantly change from baseline (396.07±64.86 μm) to month 24 (392.04±72.72 μm, p=0.570)., Conclusion: Even in low-stage ERM, inner retinal changes, including GCIPL thickness, occurred during follow-up periods, which might be owing to degenerative changes or centrifugal movement., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: To evaluate the repeatability and diurnal variation of the retinal vessel density and foveal avascular zone parameters using optical coherence tomography angiography., Methods: Forty-one healthy individuals were measured twice in the morning and once in the evening. Foveal avascular zone area, perimetry, foveal density; superficial and deep capillary plexus (superficial capillary plexus, deep capillary plexus) vessel density, and central macular thickness were evaluated with the intraclass correlation coefficient, coefficient of repeatability, and Bland-Altman plots., Results: Repeatability was evaluated with two consecutive scans taken in the morning. The coefficient of repeatabilities (%) was 5.4; 4.3, and 8.8 for the foveal avascular zone area, perimetry, and foveal density, respectively, with excellent intraclass correlation coefficients. Intraclass correlation coefficient was poor for parafovea (0.33), whereas excellent for fovea (0.97) in superficial capillary plexus-vessel density. Coefficient of repeatability for fovea and parafovea was 19.19% and 10.43%, respectively. Intraclass correlation coefficient values were poor (0.3-0.4) with 10% to 16% measurement differences in deep capillary plexus-vessel density parameters. Coefficient of repeatabilities for central macular thickness was between 1% and 2% with excellent intraclass correlation coefficient. The analysis on diurnal variation yielded comparable results., Conclusion: Except for the parafoveal vessel density, optical coherence tomography angiography is a highly reproducible device for measuring foveal avascular zone and vessel density using 6 × 6 scans with undilated pupils. However, variation in optical coherence tomography angiography parameters observed throughout the day could be attributed to test-retest variation rather than diurnal rhythm.

Objective: To evaluate the macular microvascular changes using optical coherence tomographic angiography (OCT-A) in children with unilateral amblyopia and their reversibility during treatment., Methods: Patients with unilateral strabismic or anisometropic amblyopia or residual amblyopia from early congenital cataract surgery, examined between October 2019 and March 2021, were included. Vessel density and perfusion density in the superficial capillary plexus and area, perimeter and circularity of the foveal avascular zone (FAZ) were analysed using OCT-A in amblyopic eyes, contralateral eyes and control group healthy eyes. Correlation analyses between the microvascular parameters and the visual acuity were performed. In a pilot study on a few patients from the amblyopic cohort, longitudinal follow-up during treatment was also performed., Results: A total of 128 eyes of 64 patients were included: 32 amblyopic eyes compared with 32 contralateral eyes and 64 control eyes. Vessel density and perfusion density in the superficial capillary plexus were significantly lower in amblyopic eyes compared to control eyes in 6 × 6 mm ( p  < 0.02) and 3 × 3 mm ( p  < 0.01) scans. Correlation analyses showed a linear decrease in vessel density and perfusion density with decreasing visual acuity. The microvascular changes observed were reversible with the occlusion treatment of amblyopia ( p  < 0.001)., Conclusions: The study found a decrease in vessel density and perfusion density in the macula of children with unilateral functional amblyopia. These microvascular changes were correlated with visual acuity and appeared to be reversible with treatment of amblyopia. On the whole, OCT-A appears to be a relevant complementary examination when it comes to diagnosing and monitoring functional amblyopia., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Purpose: To characterize an epiretinal neovascular membrane (ERNM) through multimodal imaging in the context of a patient with Macular Telangiectasia type 2 (MacTel) and ipsilateral concomitant ocular ischemic syndrome (OIS)., Methods: Case report, with ultra-wide field (UWF) retinography, fluorescein angiography (FA), swept source optical coherence tomography (ss-OCT), and OCT-angiography (OCTA). Written informed consent for patient information and images to be published was provided by the patient. Approval from the Research Ethics Committee of the Hospital was obtained for publication., Case Report: Yearly follow up of a 51 year-old-female patient with advanced bilateral MacTel showed new punctate hemorrhages in all four quadrants of her right eye (OD). OCTA showed an ERNM in the superficial capillary plexus of the same eye and FA confirmed the ERNM and demonstrated peripheral ischemia. Carotid ultrasound was performed and complete right carotid artery occlusion was confirmed. These findings allowed the diagnosis of an ERNM associated with Mactel and OIS., Conclusions: Interestingly, this case shows an ERNM diagnosed by multimodal imaging in a patient with advanced MacTel and a concomitant OIS. Mactel is a neurodegenerative disease which in its neovascular stage has been associated with macular neovascular membranes, but also ERNM have recently been described by OCTA., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Purpose: This study was performed to assess the prevalence of the vascularized foveal zone, including macular-foveal capillaries (MFC) and congenital retinal macrovessels (CRM), and to analyze the structural characteristics of the macular area in patients with MFC., Material and Methods: The first phase of the study evaluated the prevalence of MFC and CRM. Optical coherence tomography angiography (OCT-A) was performed, and OCT-A images of the foveal avascular zone were analyzed. In the second phase, two groups were formed: the MFC group (12 eyes, 9 patients, mean age 43.8±10.7 years) and the control group (18 eyes, 17 patients, mean age 43.0±11.8 years). A comparative analysis was performed assessing central retinal thickness (CRT), thickness of retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer (INL), outer plexiform layer (OPL), outer nuclear layer (ONL), and foveal pit depth., Results: MFCs were detected in 45 eyes from a total sample of 1031 eyes of 536 patients. The presence of CRM was recorded in three eyes of three patients. RNFL thickness was significantly higher in the MFC group in the inferior parafoveal sector (26.50 [26.00; 29.50] and 24.50 [21.75; 26.50] μm; p =0.022) and in the foveal zone (15.50 [14.00; 16.00] and 12.00 [11.00; 14.00] μm; p =0.017). Additionally, patients with MFC had a higher thickness of GCL and IPL in the fovea, inferior, nasal, and temporal parafoveal sectors. The depth of the foveal pit was significantly lower in the MFC group compared to the control group (83.0 [77.4; 101.6] and 128.0 [107.5; 147.05] μm; p =0.001)., Conclusion: The prevalence of MFC was 4.36% (calculated per number of eyes), while the prevalence of CRM - 0.29%. The macular area in patients with MFC had increased thickness of the inner retinal layers and decreased depth of the foveal pit, suggesting potential disruption in the natural process of ganglion cell migration and apoptosis during embryogenesis.

Aim: The present study evaluates the possible effects of COVID-19 on choroid thickness, the Foveal Avascular Zone (FAZ) and retinal vascular indices in the same individuals who had Optical Coherence Tomography (OCT) and Optical Coherence Tomography Angiography (OCTA) data prior to the COVID-19 pandemic., Methods: The OCT and OCTA images of the same individuals with no known ophthalmic pathology who developed a COVID-19 infection were obtained were retrieved retrospectively from the database and compared with the repeated images of OCT and OCTA images 1-2 months after COVID-19 infection., Results: Eighty eyes of 40 patients (26 female [65%], 14 male [35%]) who had developed a prior Covid-19 infection were included in the study. When comparing the measurements of the same participants before and after Covid-19 infection, no significant difference was detected in the mean average choroidal thicknesses (p=0.998), average superficial (p=0.425) and deep (p=0.333) retinal vascular densities, and superficial (p=0.991) and deep (p=0.075) FAZ measurements., Conclusions: No significant effect of COVID-19 on choroid thickness, FAZ or retinal vascular densities was noted in the present study, although there are some studies in literature with equivocal results., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest. They are responsible for the content and writing of this article., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Objective: To investigate the correlation between the cross-sectional area of the macular hole (MH) cavity and the blood flow density in different retinal layers, as well as the impact of cavity size on preoperative and postoperative retinal function in patients with idiopathic macular holes (IMH). Methods: A retrospective cohort study was conducted. Clinical data were collected from 18 patients (18 eyes) diagnosed with IMH who underwent vitrectomy combined with internal limiting membrane peeling at Shanxi Eye Hospital affiliated to Shanxi Medical University from August 2019 to December 2021. Visual acuity, best-corrected visual acuity (BCVA), spectral-domain optical coherence tomography (SD-OCT), optical coherence tomography angiography (OCTA), and multifocal electroretinography (mfERG) were performed preoperatively and at 1, 3, and 6 months postoperatively. Blood flow density data were collected for the overall retina, macular center fovea, and parafoveal regions, and the cavity cross-sectional area was measured using ImageJ software. Ten healthy subjects without retinal abnormalities who underwent mfERG at Shanxi Eye Hospital affiliated to Shanxi Medical University during the same period were included as a control group. One eye was randomly selected for each subject, with 5 left eyes and 5 right eyes. Statistical analysis was performed using Pearson correlation analysis, independent samples t-test, and repeated measures analysis of variance. Results: All 18 IMH patients had unilateral disease, including 3 males and 15 females, with an average age of (64.22±4.33) years and a duration of illness of 75 (38, 120) days. In the control group, consisting of 10 subjects, 4 were male and 6 were female, with an average age of (63.67±6.96) years. Preoperatively, all 18 affected eyes exhibited a macular hole cavity, which closed and disappeared one month postoperatively. The total cavity cross-sectional area was (4.84±2.28) mm2, with an average area of (0.27±0.13) mm 2 . The cavity cross-sectional area was positively correlated with the MH height ( r =0.82, P <0.001), ellipsoid zone disruption diameter ( r =0.74, P <0.001), and preoperative BCVA ( r =0.62, P =0.006). The cavity cross-sectional area was positively correlated with the blood flow density of the superficial macular center fovea ( r =0.47, P =0.049) and negatively correlated with the blood flow density of the deep retina ( r =-0.50, P =0.033) and deep parafoveal blood flow density ( r =-0.65, P =0.003). Compared to healthy eyes in the control group, IMH eyes showed decreased amplitudes of P1 and N1 waves in mfERG, prolonged P1 wave latency except at ring 1 (2.18° outward from the foveal center), and prolonged N1 wave latency except at ring 2 (7.46° outward from the foveal center) and 5 (29.75° outward from the foveal center) (all P <0.05). The cavity cross-sectional area was only related to the preoperative latency of the N1 wave at ring 2 ( r =0.64, P =0.004) and had an effect on the changes in the preoperative and postoperative latency of P1 and N1 waves at ring 1 and 5 ( F =4.94, 5.96; P =0.042, 0.027). Time changes had no effect on the preoperative and postoperative amplitudes and latencies of mfERG P1 and N1 waves (all P >0.05), but the interaction between cavity cross-sectional area and time had statistical significance for the amplitudes of P1 at ring 1 and N1 at ring 2( F =6.89, 3.76; P =0.003, 0.035). Conclusions: In patients with IMH, a larger macular hole cavity cross-sectional area is associated with lower blood flow density, particularly in the deep parafoveal region, poorer visual acuity, and decreased retinal function at 7.46° outward from the foveal center.

Purpose: To assess the capillary non-perfusion in different concentric sectors on widefield optical coherence tomography angiography (WF-OCTA) and to correlate the ratio of non-perfusion (RNP) to the severity of sickle cell retinopathy (SCR)., Methods: This retrospective, cross-sectional study included eyes of patients with various sickle cell disease (SCD) genotypes having undergone WF-OCTA and ultra-widefield color fundus photography (UWF-CFP). Eyes were grouped as no SCR, non-proliferative SCR or proliferative SCR. RNP was assessed on WF-OCTA montage in different field-of-view (FOV) sectors centered on the fovea: 0-10-degrees circle excluding the foveal avascular zone, the 10-30-degrees circle excluding the optic nerve, the 30-60-degrees circle, and the full 60-degrees circle., Results: Forty-two eyes of twenty-eight patients were included. Within each SCR group, mean RNP of the FOV 30-60 sector was higher than all other sectors (p < 0.05). Mean RNP of all sectors were significatively different between no SCR group and proliferative SCR group (p < 0.05). To distinguish no SCR versus non-proliferative SCR FOV 30-60 had a good sensitivity and specificity of 41.67% and 93.33%, respectively (cutoff RNP > 22.72%, AUC = 0.75, 95% CI 0.56-0.94, p = 0.028). To differentiate non-proliferative versus proliferative SCR, FOV 0-10 had good sensitivity and specificity of 33.33% and 91.67%, respectively (cutoff RNP > 18.09, AUC = 0.73, 95% CI 0.53 to 0.93, p = 0.041). To discern no SCR versus proliferative SCR, all sectors had optimal sensitivity and specificity (p < 0.05)., Conclusion: WF OCTA-based RNP provides non-invasive diagnostic information regarding the presence and severity of SCR, and correlates with disease stage in certain FOV sectors., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: To examine the association between optical coherence tomography angiography (OCTA) retinal measurements and Parkinson's disease (PD)., Methods: We searched MEDLINE and EMBASE from inception up to November 5th, 2021 for studies examining the differences between OCTA retinal measurements in PD patients and healthy controls. We used the Hartung-Knapp-Sidik-Jonkman random-effects method to combine study-specific standardized mean differences (SMD) in pooled effect estimates and a meta-analytic extension of the E-value metric to quantify the confounding bias capable of nullifying the pooled estimates., Results: Nine eligible studies for our systematic review were identified through our search strategy. The pooled SMD between the retinal vessel density of PD patients and healthy participants in the whole superficial vascular plexus (SVP), foveal SVP, parafoveal SVP and foveal avascular zone (FAZ) was -0.68 (95% CI: -1.18 to -0.17, p value = 0.02, n = 7 studies), -0.14 (95% CI: -0.88 to 0.59, p value = 0.62, n = 5 studies), -0.59 (95% CI: -1.41 to 0.23, p value = 0.12, n = 5 studies) and -0.20 (95% CI: -0.79 to 0.38, p value = 0.39, n = 5 studies), respectively. An unmeasured confounder would need to be associated with a 3.01-fold, 1.54-fold, 2.81-fold and 1.70-fold increase in the risk of PD and OCTA retinal measurements, in order for the pooled SMD estimate of vessel density in whole SVP, parafoveal SVP and FAZ, respectively, to be nullified., Conclusions: Our results provide evidence on an inverse association between whole SVP vessel density and PD., (© 2023. The Author(s), under exclusive licence to The Royal College of Ophthalmologists.)

Purpose: To compare the angle of retinal arteries and macular vessel density and foveal avascular zone (FAZ) in early stage familial exudative vitreoretinopathy (FEVR) patients with inner retinal layer (IRL) persistence with FEVR patients without IRL persistence and normal people., Methods: This study enrolled 113 early stage FEVR patients and 55 age-matched normal subjects. FEVR patients were divided into IRL group and non-IRL group based on the presence or absence of IRL in fovea. The angle of superior temporal and inferior temporal branch retinal arteries on ultra-wide-field fundus images were measured. Superficial and deep vessel density of whole image, fovea and parafovea, the area and perimeter of FAZ, A-circularity index (AI, perimeter/standard circle perimeter with equal area) and vessel density around the 300-μm width of the FAZ (FD), central macular thickness (CMT) on 3 mm × 3mm OCTA were measured., Results: 30 FEVR patients in IRL group, 83 FEVR patients in non-IRL group, 55 normal people in control group were evaluated. BCVA were worst in IRL group ( p  < .001). The angle of retinal arteries was smaller in FEVR groups ( p  < .001) and were smallest in IRL group ( p  < .001). Superficial and deep vessel density of whole and parafovea area in FEVR patients were significantly lower than that in normal people ( p  < .05), AI were biggest ( p  = .01) and FD were smallest in IRL group ( p  < .001). CMT in IRL group were thicker than non-IRL group and control group ( p  < .05)., Conclusion: Worse BCVA, smaller angle of retinal arteries (more vessels traction), lower macular vessel density, smaller and more irregular FAZ and thicker CMT were observed in FEVR patients with IRL persistence even in early stage.

Purpose: Recent studies have questioned the traditional view, which regards Coats disease as a strictly unilateral entity. Applying optical coherence tomography angiography, this prospective, monocentric study investigates quantitative capillary changes of the macula associated with Coats disease., Methods: Twenty-four eyes (4 untreated, 8 pre-treated) of 12 patients with stage 2 Coats disease (age range: 9-61 years) and 15 eyes of healthy, age-matched controls from the University of Muenster Medical Center, Germany received macular optical coherence tomography angiography measurements of the superficial, deep, and choriocapillary capillary plexus. Flow density and parameters related to the foveal avascular zone were compared between Coats eyes and fellow eyes, and between fellow eyes and control eyes. Additional subanalyses investigated changes based on disease stage., Results: Flow density did not differ between fellow eyes of Coats disease patients and control eyes in any of the parameters investigated. Comparison of Coats eyes to their respective fellow eyes revealed Coats disease to be associated with lower flow density in superficial, deep, and choriocapillary capillary plexus regions, irrespective of disease stage (all P < 0.03). There were no noticeable differences regarding the size or symmetry of the foveal avascular zone., Conclusion: In light of the recent discussion around the unilateral character of Coats disease, this trial provides evidence against a bilateral presentation of vascular changes in the macula., Competing Interests: The authors report no conflict of interest., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the Opthalmic Communications Society, Inc.)

We analyzed whether macular superficial vascular density (SVD) and foveal vascular zone (FAZ) on optical coherence tomography angiography (OCTA) can distinguish between bilateral ametropic and anisometropic amblyopia. We included 42, 33, and 50 eyes in the bilateral ametropic amblyopia, anisometropic amblyopia, and normal control groups, respectively. Using macular swept-source optical coherence tomography angiography, we measured and analyzed the superficial FAZ areas and five sectoral macular SVDs after magnification correction. The anisometropic amblyopic eye group showed significantly increased foveal SVDs (p < 0.001) and significantly decreased superficial FAZ areas (p < 0.001), compared with the remaining groups. Additionally, the bilateral ametropic amblyopia group had significantly decreased nasal SVDs. SVDs and superficial FAZ areas differed among hyperopic amblyopia subtypes. These findings may reflect vascular distribution differences and macular changes in hyperopic amblyopia subtypes compared with normal eyes., (© 2023. Springer Nature Limited.)

Purpose: During routine eye examinations, we noticed widened and flattened foveal pits with loss of normal V-shaped foveal profile and a pseudohole-like appearance in some otherwise healthy hypermetropic children. Our purpose was to describe clinical significance and multimodal imaging features of this incidental finding., Methods: Prospectively, 25 eyes of 13 hypermetropic children with these foveal changes and 36 eyes of 19 hypermetropic children with normal foveal appearance were enrolled. The macular thickness measurements and foveal parameters including pit diameter, depth, base, and area obtained by optical coherence tomography (OCT) (Heidelberg Spectralis, Heidelberg Engineering, Heidelberg, Germany), macular superficial and deep vessel density (VD) and foveal avascular zone values obtained by optical coherence tomography angiography (Avanti RTVue‑XR; Optovue, Fremont, CA, USA) were noted. The correlations of these parameters with visual function were evaluated., Results: In the study group, significantly widened and flattened pit contours with decreased central foveal thickness (p = 0.01), and increased distance between foveal edges (p < 0.001) were observed. While the whole image superficial macular VD was similar between the groups (p = 0.74), a significant decrease in deep macular VD was observed in the study group (p = 0.01). None of these changes were correlated with visual acuity., Conclusion: Wider and flattened foveal pits described here represent a newly defined variation in healthy hypermetropic children. Although a correlation with visual acuity was not evident, these changes in foveal profile are shown to be related with macular microvascular changes in deep capillary plexus. Awareness of these morphologic changes will help clinicians in the differential diagnosis of macular pseudohole., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Objective: The foveal avascular zone (FAZ) is altered in patients with retinal vein occlusion (RVO) and correlates inversely with visual acuity. Optical coherence tomography angiography (OCTA) is an imaging tool to visualize FAZ safely and easily. Automated measurements can facilitate interpretation of OCTA images. In this comparative cross-sectional study, we compare the results of manual measurement of the FAZ with automated measurement by built-in application (Metrix)., Methods: The study included patients with RVO who underwent OCTA. Manual measurement was compared with automated evaluation by Metrix in 3 mm x 3 mm and 6 mm x 6 mm scan sizes and correlations of the circularity, circumference, and size of the FAZ were calculated., Results: Forty-seven eyes were included in the study. A reliable measurement result in both Metrix 3 mm x 3 mm and 6 mm x 6 mm was found in only 25 of 47 eyes. The mean FAZ in these eyes by manual measurement was 0.50 mm 2 compared with 0.20 mm 2 and 0.24 mm 2 , respectively, by automated measurement. A statistically significant inverse correlation was found in both the automated 3 mm x 3 mm and 6 mm x 6 mm measurements for FAZ circumference with FAZ circularity but not FAZ area., Conclusion: The two automated measurements showed no significant bias regarding the size of the FAZ, but the plausibility of the data should be checked on a case-by-case basis. The manual measurements were higher, indicating limited agreement of manual and automated measurements. The information on circularity can point to ischemic maculopathy early in the course of the disease. [ Ophthalmic Surg Lasers Imaging Retina 2023;54:462-469.] .

Purpose: To evaluate the changes in macular blood flow after cataract surgery through optical coherence tomography angiography (OCT-A)., Methods: In this prospective case series, 50 patients who underwent uncomplicated cataract surgery by the resident were included. OCT-A images and complete ocular examinations were performed at baseline, 1 and 3 months postoperatively. The changes in OCT-A parameters including foveal avascular zone (FAZ) area, vessel density (VD) of superficial and deep plexus, and central macular thickness were assessed before and after surgery. Cataract grading, intraocular inflammation, and duration of surgery were analyzed., Results: FAZ was significantly reduced from 0.36 ± 0.13 mm 2 at baseline to 0.32 ± 0.12 mm 2 at month 1 (P < 0.001) and this reduction continued until month 3. In the superficial layer, vessel density of the fovea, parafovea, and whole image significantly increased from 13.9 ± 6.8, 43.7 ± 4.7, and 43.2 ± 4.4 at baseline to 18.4 ± 7.9, 45.7 ± 4.9, and 44.9 ± 4.5 at month 1. The increase in the vessel density of the deep layer was similar to the superficial layer. Accordingly, CMT at the fovea was significantly increased from 240.5 ± 21.99 µm at baseline to 253.1 ± 23.2 microns at month 1 (P < 0.001) and the increase significantly continued and reached 259.5 ± 22.6 µm at month 3 (P < 0.001). Accordingly, the FAZ area significantly reduced one month postoperatively. In regression analysis, CMT changes positively correlated with cataract grading. FAZ area negatively correlated with intraocular inflammation on the first postoperative day., Conclusion: The present study shows that CMT and vessel density of the macula significantly increase after uncomplicated cataract surgery, while the FAZ area reduces. Postoperative inflammation could be the possible explanation for the findings of this study., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: We aim to characterise the ophthalmic findings and retinal vasculature changes in patients with WS, and to analyse the correlation between ophthalmic manifestations and the associated systemic diseases., Methods: This retrospective case-control study included 27 WS patients and 28 age-matched healthy participants. Stellate pattern of iris, central macular thickness (CMT), foveal width, retinal vessel diameter, superficial vascular density (SVD) of macula and foveal avascular zone (FAZ) were compared between WS patients and healthy participants., Results: Twenty-five patients (93%) had the classic stellate iris presentation. Compared with healthy controls, WS patients had decreased CMT, increased foveal width and a lower SVD of macula (all P < 0.001). Significantly decreased mean retinal arterial (117.9 ± 9.9 µm vs. 133.0 ± 6.7 µm in WS and controls, respectively; p < 0.001) and venous (158.9 ± 11.2 µm vs. 174.0 ± 8.0 µm in WS and controls, respectively; p < 0.001) outer diameters, as well as mean arterial wall thickness (11.2 ± 1.3 µm vs. 12.2 ± 0.8 µm in WS and controls, respectively; p < 0.01) were found in WS. Stellate iris grading was significantly associated with CMT, foveal width, retinal vessel diameter (all p < 0.05), and a significant increase in the odds of having hypertension (Odds ratio (OR), 5.63; P < 0.05). The severity of stellate iris in WS seemed to have the trend of increasing risk of having pulmonary stenosis, tricuspid regurgitation and mitral regurgitation., Conclusions: This study provides the first in vivo evidence reflecting current knowledge on vessel morphology in WS patients that deficient circumferential growth is the predominant pathophysiologic changes resulting from elastin deficiency. The ophthalmic characteristics may serve as a complementary tool to diagnose and follow-up patients suffering from WS., (© 2022. The Author(s), under exclusive licence to The Royal College of Ophthalmologists.)

Purpose: To investigate foveal photoreceptor configuration in Alport syndrome, a rare inherited disease characterized by Collagen IV dysfunction., Methods: Adaptive optics scanning laser ophthalmoscope (AOSLO) in vivo imaging of the foveal center and quantitative analysis of cone photoreceptor topography in a 17-year-old male patient with Alport syndrome presenting absence of a foveal avascular zone (FAZ) and foveal hypoplasia in both eyes., Results: Cone density analysis based on AOSLO images revealed an unusual linear cone topography profile displaying supernormal densities within the fovea (z-scores up to + 3.57 and + 2.97 in right and left eyes, respectively)., Conclusion: Foveal hypoplasia has previously been associated with normal or reduced cone density. Our observation is the first case of disease-related supernormal cone density within the foveola, shedding light upon the role of Collagen IV in foveal maturation.

Purpose: To establish an analysis method using diffeomorphic image registration and evaluate microvascular displacement through epiretinal membrane (ERM) removal., Methods: Medical records of eyes that underwent vitreous surgery for ERM were reviewed. Postoperative optical coherence tomography angiography (OCTA) images were converted to the corresponding preoperative images according to a configured algorithm using diffeomorphism., Results: Thirty-seven eyes with ERM were examined. Measured changes in the foveal avascular zone (FAZ) area showed a significant negative correlation with central foveal thickness (CFT). The average amplitude of microvascular displacement calculated for each pixel was 69 ± 27 µ m in the nasal area, which was relatively smaller than that in other areas. The vector map, which included both the amplitude and the vector of microvasculature displacement, showed a unique vector flow pattern called the rhombus deformation sign in 17 eyes. Eyes with this deformation sign showed less surgery-induced changes in the FAZ area and CFT and a milder ERM stage than those without this sign., Conclusion: The authors calculated and visualized microvascular displacement using diffeomorphism. The authors found a unique pattern (rhombus deformation) of retinal lateral displacement through ERM removal, which was significantly associated with the severity of ERM.

To investigate the preoperative morphology of the foveal avascular zone (FAZ) for prediction of the postoperative visual acuity in advanced idiopathic epiretinal membrane (ERM). 28 patients (28 eyes) with unilateral idiopathic ERM who underwent pars plana vitrectomy with internal limiting membrane peeling were included. Superficial FAZ was measured preoperatively in both eyes using optical coherence tomography angiography. Area, perimeter, and circularity of FAZ were achieved, and the differences between the ERM eyes and the contralateral eyes were evaluated to analyze the degree of FAZ distortion in diseased eyes. The best-corrected visual acuity (BCVA) and central foveal thickness (CFT) were measured at baseline and more than 6 months after surgery. The correlations of the preoperative FAZ with BCVA and CFT were assessed. The FAZ in the eyes with ERM was significantly reduced, and the BCVA was significantly correlated with the FAZ area (FAZa) (P = 0.001) and the FAZ perimeter (FAZp) (P < 0.001) before surgery. LogMAR BCVA and CFT were significantly improved from 0.550 ± 0.221 to 0.354 ± 0.229 (P = 0.008), and from 524.393 ± 93.575 µm to 400.071 ± 75.979 µm (P < 0.001) after surgery. The preoperative FAZa and FAZp were significantly associated with letter score gain (P < 0.001, P < 0.001) and the postoperative final BCVA (P = 0.026, P = 0.006). The preoperative FAZp had correlation with ratio of postoperative to preoperative CFT (P = 0.016). The preoperative FAZp is a predictor of visual acuity and morphological prognosis after surgery in advanced idiopathic ERM., (© 2023. The Author(s).)

Aim: The present study explores the effects of Body Mass Index (BMI) on choroidal thickness, the deep and superficial retinal capillary plexuses, and the foveal avascular zone (FAZ)., Methods: The subjects in this prospective study were divided into five groups based on their calculated BMI. Choroidal thickness, superficial and deep retinal capillary plexuses, and FAZ were measured using enhance depth imaging (EDI) and optical coherence tomography angiography (OCTA). The groups were then compared and correlations with BMI were evaluated., Results: The study included 210 eyes of 105 subjects. The comparison of the BMI groups revealed a significant decrease in the mean choroidal thicknesses in the obese groups (p = 0.001), and a significant negative correlation between BMI and mean choroidal thickness (p = 0.02). The results of the analysis of the mean superficial and deep retinal capillary plexuses did not differ between the groups (p = 0.089, p = 0.808 respectively), while the deep FAZ measurements revealed a significant decrease in the obese groups (p = 0.003)., Conclusion: Choroidal thickness and deep FAZ are significantly negatively correlated with BMI, suggesting potential choroidal and retinal microvascular effects of obesity., Competing Interests: Declaration of Competing Interest The authors declare no conflicts of interest, and are fully responsible for the content and writing of this article., (Copyright © 2023. Published by Elsevier B.V.)

Purpose: To investigate changes in retinal microcirculation in patients recovered from COVID-19 infection compared to healthy controls, using optical coherence tomography-angiography., Methods: Meta-analysis of eligible studies comparing retinal microcirculation between patients recovered from COVID-19 infection and healthy controls up to 7th of September 2022 was performed, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2009 guidelines. The following search algorithm was used: (COVID-19 OR coronavirus) AND (retina OR optical coherence tomography OR optical coherence tomography angiography OR vessel density OR foveal avascular zone). Standardized Mean Difference (SMD) with 95% confidence interval (CI) was calculated to compare continuous variables. Revman 5.3 was used for the analysis., Results: 12 studies were included in our analysis. Foveal avascular zone (FAZ) area was larger in patients recovered from COVID-19 infection compared to healthy controls, while there was no statistically significant difference in FAZ perimeter between the two groups. The foveal, parafoveal and whole image vessel density in the superficial capillary plexus showed no significant difference between the two groups. The foveal, parafoveal and whole image vessel density in the deep capillary plexus was statistically lower in patients recovered from COVID-19 compared to healthy controls., Conclusion: FAZ area was enlarged and foveal, parafoveal and whole image vessel density in deep capillary plexus were reduced in patients recovered from COVID-19 infection compared to healthy controls, suggesting that COVID-19 infection may induce long-term retinal microvascular changes in patients recovered from the virus infection., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Purpose: There is evidence of decreased vessel density in optical coherence tomography angiography (OCTA) after Covid-19. We aimed to investigate whether the outcome of retinal vasculopathy would be worse if patients with diabetes mellitus (DM) were infected with coronavirus using OCTA to assess retinal vessels., Methods: One eye of each subject was included in the study. Diabetic patients without retinopathy and non-diabetic controls were divided into four groups according to their Covid-19 history: group 1=DM(-)Covid-19(-); group 2=DM(+)Covid-19(-); group 3=DM(-)Covid-19(+); and group 4=DM(+)Covid-19(+). All Covid-19 patients were not hospitalised. Macular OCTA scans were performed in a 6 × 6 mm area., Results: Diabetes had no effect on the area of the foveal avascular zone (FAZ), but Covid-19 caused an increase in FAZ area. Diabetes and Covid-19 had an effect on both the superficial capillary plexus (SCP) and the deep capillary plexus (DCP) in the fovea. Eta squared (ƞ2) is a measure of effect size. The effect size of Covid-19 (ƞ2=0.180) was found to be greater than that of diabetes (ƞ2=0.158) on the SCP, whereas the effect size of diabetes (ƞ2=0.159) was found to be greater than that of Covid-19 (ƞ2=0.091) on the DCP., Conclusions: The percentage of vessel density was lower in the fovea and the FAZ area was enlarged in the diabetic patients who recovered from Covid-19. In diabetic patients Covid-19 may lead to deterioration of vascular metrics., Competing Interests: Declaration of Competing Interest The authors have no relevant financial of non-financial interest to disclose., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Objective: To analyze the influence factors of the area of superficial plexus foveal avascular zone (FAZ) and related indexes of fovea measured with optical coherence tomography angiography (OCT-A) in normal subjects., Methods: This was a cross-sectional study from November 2020 to May 2021 in the Inner Mongolia Autonomous Region, China. Each subject received related eye examination. The correlation between all the factors and superficial plexus FAZ were analyzed under univariable and multivariable linear regression analysis., Results: Finally, 239 subjects with sufficient data were recruited in the study, including 108 males and 131 females, aged 27.41±4.63 years. The area of superficial plexus FAZ was 0.33±0.16 mm 2 . In the univariate regression, gender (β = 41.702, 95%CI: 9.152 to 74.253, P = 0.012), drinking (β = -66.074, 95%CI: -99.197 to -32.951, P = 0.001) and axial length (β = -15.874, 95%CI: -29.562 to -2.185, P = 0.023) were associated with superficial plexus FAZ area. In multivariate regression analysis results, drinking (β = -42.410, 95%CI = -79.388 to -5.432, P = 0.025) was significantly correlated with superficial plexus FAZ area., Conclusion: The area of superficial plexus FAZ was not affected by age, gender, systematical and biochemical indicators, but related to the status of drinking., Competing Interests: Declaration of Competing Interest The authors declare no conflicts of interest in relation to this work., (Copyright © 2023. Published by Elsevier B.V.)

Background: To demonstrate the associations between the morphology of macular retinal vasculature and disease severity of idiopathic epiretinal membrane (ERM)., Methods: Macular structures were assessed using optical coherence tomography (OCT), and were classified as "with pseudohole" or "without pseudohole". The 3 × 3 mm macular OCT angiography images were analyzed using the Fiji software to obtain the vessel density, skeleton density, average vessel diameter, vessel tortuosity, fractal dimension, and foveal avascular zone (FAZ)-related parameters. The correlations between these parameters and ERM grading as well as visual acuity were analyzed., Results: For ERM with or without a pseudohole, increased average vessel diameter, decreased skeleton density, and decreased vessel tortuosity were all associated with inner retinal folding and thickened inner nuclear layer, indicating more severe ERM. In 191 eyes without a pseudohole, the average vessel diameter increased, fractal dimension decreased and vessel tortuosity decreased with increasing ERM severity. The FAZ was not associated with ERM severity. Decreased skeleton density (r = -0.37), vessel tortuosity (r = -0.35), and increased average vessel diameter (r = 0.42) were correlated with worse visual acuity (All P < 0.001). In 58 eyes with pseudoholes, a larger FAZ was associated with a smaller average vessel diameter (r = -0.43, P = 0.015), higher skeleton density (r = 0.49, P < 0.001), and vessel tortuosity (r = 0.32, P = 0.015). However, none of the retinal vasculature parameters correlated with visual acuity and central foveal thickness., Conclusion: Increased average vessel diameter, decreased skeleton density, decreased fractal dimension and decreased vessel tortuosity were good indicators of ERM severity and associated visual impairment., (© 2023. The Author(s).)

Purpose: To identify the characteristics of the retinal microvasculature in epiretinal membrane patients with ectopic inner foveal layer (EIFL)., Methods: Patients were classified into two groups: those without EIFL (Group 1) and those with EIFL (Group 2). The vessel density (VD), perfusion density (PD), and the foveal avascular zone (FAZ) parameters were compared using optical coherence tomography angiography. Linear regression analysis was performed to identify the optical coherence tomography angiography parameters associated with best-corrected visual acuity., Results: The VD of the central area in Group 1 and Group 2 was 11.6 ± 3.3 and 17.2 ± 2.8 mm -1 , respectively ( P < 0.001), the PD of the central area was 21.7 ± 6.2 and 32.0 ± 5.5%, respectively ( P < 0.001), and the FAZ area was 0.24 ± 0.11 and 0.09 ± 0.08 mm 2 , respectively ( P < 0.001). Based on the linear regression analysis, the VD of the central area (B = 0.018, P = 0.003), the PD of the central area (B = 0.009, P = 0.004), and FAZ area (B = -0.489, P = 0.013) were significantly associated with best-corrected visual acuity in patients with epiretinal membrane., Conclusion: The VD and PD of the foveal area were significantly higher in patients with EIFL, and the FAZ area was lower in patients with EIFL than in those without EIFL. In addition, the VD and PD of the foveal area were negatively associated with best-corrected visual acuity, and the FAZ area was positively associated with best-corrected visual acuity in patients with epiretinal membrane.

Purpose: To analyze the vascular structure of the healthy pediatric population using optical coherence tomography angiography (OCTA), and to investigate its relationship with ocular parameters., Materials and Method: This cross-sectional, prospective study included 142 eyes of 71 healthy subjects aged 8-18 years. All patients underwent a complete ocular assessment, biometric evaluation and OCTA analysis. Anterior chamber depth, axial length, corneal thickness values were also reported and their relationship with OCTA measurements was evaluated., Results: There was no statistical difference between girls and boys in terms of demographic characteristics (p>0.05). Neither vascular density in the deep and superficial capillary plexus nor FAZ area was significantly related to the ocular parameters or age of any patient in the study., Conclusions: Despite the relatively small number of participants, this study may represent normative data for the Turkish pediatric population. It was also shown that vascular density and FAZ area in childhood are not affected by age, axis length, anterior chamber depth, cornea and foveal thickness., Competing Interests: Declaration of Competing Interest No potential conflict of interest relevant to this article was declared., (Copyright © 2023. Published by Elsevier B.V.)

Purpose: To compare macula vascular parameters in optical coherence tomography angiography (OCTA) of children with history of retinopathy of prematurity (ROP) who were treated with laser photocoagulation (LPC) or intravitreal Bevacizumab therapy., Methods: Forty eyes of 28 ROP children treated with LPC and 36 eyes of 22 ROP children treated with intravitreal Bevacizumab and 40 eyes of 40 age-gender matched term children were included the study. Capillary plexus densities in macula, FAZ parameters, outer retina and choriocapillaris flow rates, and central foveal thickness were measured., Results: Foveal superficial and deep capillary plexus densities were found significantly higher in LPC and intravitreal Bevacizumab injection (IBI) groups compared to control group. FAZ area was found significantly lower in LPC and IBI groups compared to control group (p ‹ 0.001). Higher foveal superficial capillary plexus density, higher central foveal thickness, and lower FAZ area were found to be associated with poorer visual acuity in correlation analysis (p ‹ 0.05). In IBI group, earlier anti-VEGF therapy was found to be associated with lower foveal superficial capillary plexus density., Conclusion: Microvascular characteristics such as FAZ area and capillary plexus densities of macula are deteriorated in ROP. There is no significant difference between the treatment alternatives of ROP in terms of macular microvascular parameters., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background and Objectives: Myopia is the most common refractive eye anomaly with a prevalence that is constantly increasing. High myopia is associated with numerous complications that can lead to permanent vision loss. It is believed that the basis of these complications lies in changes in the microvasculature of the retina caused by an increase in the longitudinal axis of the eye. Materials and Methods: Optical coherence tomography angiography (OCTA) was used to analyze differences in macular zone vascular and perfusion density and foveal avascular zone (FAZ) parameters in myopic subjects. The following OCTA parameters were analyzed: the vessel and perfusion density of retinal blood vessels in the superficial plexus; the area, perimeter, and index of circularity of the foveal avascular zone (FAZ); and foveal and ganglion cell complex (GCC) thickness. Results: Subjects with low myopia did not show statistically significant differences compared to the control for any of the analyzed parameters. Groups with moderate and high myopia showed a significant decrease in vessel and perfusion density in the parafoveal and the entire 3 × 3 mm analyzed field. Foveal vessel and perfusion densities in the myopic groups were similar to those of the control regardless of the degree of myopia. The area and perimeter of the FAZ, as well as foveal and mean GCC thickness, did not differ significantly no matter the degree of myopia, while the index of circularity was lower in highly myopic subjects. The minimal thickness of the GCC was also lower in the high myopia group. Conclusions: High and moderate myopia led to a loss of blood vessels in the macular region. Perfusion and vascular densities were preserved in the foveal region and were not affected by different degrees of myopia. The FAZ was not significantly larger in myopic subjects, but its circularity was lower in subjects with high myopia.

In this study, foveal, parafoveal, peripapillary anatomical, and microvascular anomalies in prematurely born children aged 4-12 years with a history of retinopathy of prematurity (ROP) were evaluated. Seventy-eight eyes of 78 prematurely born children ([tROP]: ROP with laser treatment, [srROP]: spontaneously regressed ROP) and 43 eyes of 43 healthy children were included. Foveal and peripapillary morphological parameters (including ganglion cell and inner plexiform layer (GCIPL) thickness, peripapillary retinal nerve fiber layer (pRNFL) thickness) and vasculature parameters (including foveal avascular zone area, vessel density from superficial retinal capillary plexus (SRCP), deep retinal capillary plexus (DRCP), and radial peripapillary capillary (RPC) segments) were analyzed. Foveal vessel densities in SRCP and DRCP were increased and parafoveal vessel densities in SRCP and RPC segments vessel density were decreased in both ROP groups compared with those of control eyes. The best-corrected visual acuity was negatively correlated with pRNFL thickness in the tROP group. Refractive error was negatively correlated with vessel density of RPC segments in the srROP group. In children born preterm with a history of ROP, it was found that foveal, parafoveal, and peripapillary structural and vascular anomalies and redistribution were accompanied. These retinal vascular and anatomical structure anomalies showed close relationships with visual functions., (© 2023. The Author(s).)

Purpose: The primary objective of the study was to assess the macular retinal vessel density, subfoveal choroidal thickness, and retinal layer metrics by optical coherence tomography angiography (OCTA), enhanced-depth imaging optical coherence tomography (EDI-OCT), and spectral domain optical coherence tomography (SD-OCT), respectively, in recovered COVID-19 patients and its comparison with the same in control subjects. The secondary objective was to evaluate differences in OCTA parameters in relation with the severity of COVID-19 disease and administration of corticosteroids., Methods: A case-control study was performed that included patients who had recovered from COVID-19 and age-matched healthy controls. Complete ocular examination including OCTA, SD-OCT, and EDI-OCT were performed three months following the diagnosis., Results: Three hundred sixty eyes of 180 subjects were enrolled between the two groups. A decreased mean foveal avascular zone area in both superficial capillary plexuses (P = 0.03) and deep capillary plexuses (P < 0.01), reduced average ganglion cell layer-inner plexiform layer thickness (P = 0.04), and increased subfoveal choroidal thickness (P < 0.001) were observed among cases in comparison to the control group. A significant correlation was found between sectoral macular vessel density in relation to disease severity and a decrease in vessel density with greater severity of the disease., Conclusion: OCTA detected retinal microvascular alterations following SARS-CoV-2 infection in subjects with the absence of any clinical ocular manifestation or systemic thrombotic events. These parameters could be used to help identify patients with a higher incidence of systemic thromboembolism on longer follow-ups and identify the impact of corticosteroids on retinal architecture., Competing Interests: None

Purpose: To investigate the effect of blunt ocular trauma (BOT) on foveal circulation, and in particular the foveal avascular zone (FAZ), using optical coherence tomography angiography (OCTA)., Methods: This retrospective study consisted of 96 eyes (48 traumatized eyes and 48 nontraumatized eyes) from 48 subjects with BOT. We analyzed the FAZ area of deep capillary plexus (DCP) and superficial capillary plexus (SCP) immediately after BOT and at 2 weeks after BOT. We also evaluated the FAZ area of DCP and SCP in patients with and without blowout fracture (BOF)., Results: There were no significant differences in FAZ area between traumatized and nontraumatized eyes at DCP and SCP in the initial test. In traumatized eyes, the FAZ area at SCP was significantly reduced on follow-up when compared to initial test (p = 0.01). In case of eyes with BOF, there was no significant differences in FAZ area between traumatized and nontraumatized eyes at DCP and SCP on initial test. No significant difference of FAZ area was found on follow-up relative to the initial test, whether in the DCP or SCP. In case of eyes without BOF, there was no significant differences of FAZ area between traumatized and nontraumatized eyes at DCP and SCP in initial test. Also, no significant difference of FAZ area at DCP was found on follow-up test compared to initial test. However, the FAZ area at SCP was significantly reduced in follow-up test compared with that in the initial test (p = 0.04)., Conclusions: Temporary microvascular ischemia occurs in the SCP of patients after BOT. Patients should be warned of transient ischemic changes that may occur after trauma. OCTA can provide useful information regarding the subacute changes in the FAZ at SCP after BOT, even without evident findings of structural damage on fundus examination.

Aim: : To evaluate any abnormalities on retinal examination and retinal microvascularity in patients recovered from COVID-19., Materials and Methods: : Cross-sectional, case- control study. Patients between 18 and 65 years old with PCR-confirmed SARS-CoV-2 infection and age matched controls were included. Macular and retinal nerve fiber layer thickness, vessel density of the superficial (SCP) and the deep retinal capillary plexus (DCP) and the foveal avascular zone (FAZ) were measured and compared with controls., Results: : This study included 200 eyes of 200 cases totally. Of them 105 cases were patients and 95 cases were controls. Retinal abnormalities were detected by indirect ophthalmoscopic examination in ten patients of 105 cases (10.5%). There was no statistically significant difference in the vessel density of the SCP and the DCP and the mean FAZ measurements., Conclusion: : There isn't any relevant difference between early post-COVID-19 patients and general population in terms of retinal microvascularity.

Purpose: The aim of this study was to investigate possible vascular changes in pediatric patients infected with COVID-19 and to compare these with an age-matched control group., Methods: All patients underwent an ocular assessment and optical coherence tomography angiography examination. Two vascular networks were analyzed as the superficial and deep regions., Results: Evaluation was made of 40 eyes of 20 patients who had recently recovered from COVID infection and 80 eyes of 40 healthy individuals. The DCP-VD values of the COVID group were significantly lower than the control group in most quadrants. The FAZ PERIM and FAZ area values in the COVID patients were higher than the control group, but not statistically significant (p>.05)., Conclusion: Pediatric cases of COVID-19 may differ from adults based on structural and immune response differences, and that OCTA can be a noninvasive guide for analysis of the end-organ effects of pediatric COVID disease.