Search

Background: We aimed to evaluate the retinal vascular changes in the superficial and deep retinal vascular networks in the fellow eye of patients with central retinal artery occlusion (CRAO) and compare them with controls using optical coherence tomography angiography (OCT-A). Methods: In a cross-sectional study, 27 patients with CRAO and 189 normal controls were included. Ophthalmic examination and OCT-A images were performed on all participants. Results: The total vascular density of the superficial capillary network in the 6-mm scan was significantly lower in the fellow eye of patients with CRAO than in the control group (p = 0.02). No significant difference was observed in the FAZ area of the affected eyes and their fellow eyes compared with the controls. Total vascular density at 300 microns around the fovea was lower in the fellow eye compared with the control group (p = 0.034). Conclusions: The retinal vascular network changes in the fellow eyes of patients with CRAO suggest that persistent microvascular changes may be present before the onset of CRAO. This finding indicates that such changes could serve as an early diagnostic window for systemic vascular changes before catastrophic vascular events occur. [ABSTRACT FROM AUTHOR]

This study was intended to investigate the macular vascular and photoreceptor changes for diabetic macular edema (DME) at the early stage. A total of 255 eyes of 134 diabetes mellitus patients were enrolled and underwent an ophthalmological and systemic evaluation in this cross-sectional study. Early DME was characterized by central subfoveal thickness (CST) value between 250 and 325 μm, intact ellipsoid zone, and an external limiting membrane. While non-DME was characterized by CST < 250 μm with normal retinal morphology and structure. Foveal avascular zone (FAZ) area ≤ 0.3 mm2 (P < 0.001, OR = 0.41, 95% CI 0.26–0.67 in the multivariate analysis) and HbA1c level ≤ 8% (P = 0.005, OR = 0.37, 95% CI 0.19–0.74 in multivariate analysis) were significantly associated with a higher risk of early DME. Meanwhile, no significant differences exist in cone parameters between non-DME and early DME eyes. Compared with non-DME eyes, vessel diameter, vessel wall thickness, wall-to-lumen ratio, the cross-sectional area of the vascular wall in the upper side were significantly decreased in the early DME eyes (P = 0.001, P < 0.001, P = 0.005, P = 0.003 respectively). This study suggested a vasospasm or vasoconstriction with limited further photoreceptor impairment at the early stage of DME formation. CST ≥ 250 μm and FAZ ≤ 0.3 mm2 may be the indicator for early DME detection. [ABSTRACT FROM AUTHOR]

Govetto's staging system (stages 1–4) for epiretinal membrane (ERM) based on optical coherence tomography images is a useful predictor of monocular visual function; however, an association between Govetto's stage and binocular vision has not been reported. This study aimed to investigate the factors associated with Govetto's stage among the monocular and binocular parameters. This retrospective study included consecutive patients with treatment-naïve eyes with unilateral ERM without pseudo-hole. We investigated Govetto's stage, degrees of aniseikonia and metamorphopsia, foveal avascular zone area, central retinal and choroidal thickness, vertical ocular deviation, stereopsis, and binocular single vision (BSV). We compared the parameters between the BSV-present and BSV-absent groups and investigated correlations between Govetto's stage and the monocular and binocular parameters. Twenty-eight eyes of 28 patients were examined (age, 66.6 ± 10.2 years). In multivariate correlation analyses, Govetto's stage correlated with BSV (P = 0.04, β = − 0.36) and central retinal thickness (P < 0.001, β = 0.74). Of the eyes, 18 were assigned to the BSV-present group and 10 to the BSV-absent group. Govetto's stage was significantly more advanced in the BSV-absent group than in the BSV-present group (3.2 ± 0.8 vs 2.5 ± 0.7, P = 0.03). Of the 28 patients, 11 (39%) showed small-angle vertical deviations (1–12Δ). In conclusion, our findings showed that Govetto's stage correlated with binocular vision in patients with monocular ERM. Govetto's staging is a useful parameter for predicting not only monocular but also binocular vision. [ABSTRACT FROM AUTHOR]

Purpose: To study retinal and choroidal microcirculation by optical coherence tomography angiography (OCTA) in pregnant women with unexplained recurrent spontaneous abortion (RSA) and to compare them with healthy pregnant and nonpregnant subjects. Methods: Pregnant women with an unexplained history of RSA (group 1), healthy pregnant (group 2), and healthy non-pregnant women (group 3) were included in the study. After a thorough ophthalmologic examination:best-corrected visual acuity, intraocular pressure,slit-lamp biomicroscopy, fundus examination,autorefractometer, biometry, and axial length measurement; OCT and OCTA measurements were performed with Swept Source OCT-Angiography (Topcon Co, Japan). Results: The nonpregnant group had higher values for central foveal superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density (VD) and lower values for superior, inferior, and mean VD compared with pregnant groups (p < 0.001). Choriocapillaris values (CC) VD were higher in groups 1 and 2 than in group 3 (p < 0.001). The group with unexplained RSA had a relatively smaller FAZ (foveal avascular zone) area than the group of healthy pregnant women (p:0.047). There were no statistically significant differences between groups in the retina, retinal nerve fiber layer, ganglion cell layer, and choroidal thickness (p > 0.05). Conclusion: Although our study did not identify any etiology in pregnant women with RSA, we observed detectable differences in FAZ area and vessel density values using OCTA, when comparing them with healthy pregnant women and healthy nonpregnant controls. We believe that OCTA, as used in many pathologies such as diabetic and hypertensive retinopathy and retinal vascular occlusion, can also be extended to unexplained RSA both to detect etiology and to monitor treatment in studies with a larger number of patients. [ABSTRACT FROM AUTHOR]

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 mm2, which decreased to 0.24 ± 0.07 mm2 1 month postoperatively (p < 0.001) and slightly increased to 0.25 ± 0.06 mm2 12 months postoperatively (p = 1.000). The FAZ area did not differ significantly from that of fellow eyes (0.39 ± 0.06 mm2, 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. [ABSTRACT FROM AUTHOR]

Introduction: Acute leukemia often affects microcirculation perfusion. This study aimed to investigate retinal microvascular changes in patients with acute leukemia without retinopathy during clinical remission using optical coherence tomography angiography (OCTA) and to determine the correlation of these changes with systemic laboratory values. Methods: Thirty-eight patients in remission from acute leukemia with no retinopathy (NLR group) and 36 age-matched healthy individuals (control group) were included in this cross-sectional study. OCTA parameters, including the central foveal thickness (CFT), foveal avascular zone (FAZ) area, FAZ perimeter, acircularity index (AI), foveal density (FD300), and the vessel densities (VDs) of the superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris were analyzed in a 6 × 6 mm2 macular scan. Correlation and multiple linear regression analyses were conducted to identify potential systemic characteristics associated with these OCTA metrics. Results: AI (P = 0.034) and FD300 (P < 0.001) differed significantly between the NLR and control groups. The VD of SCP in the parafovea (P = 0.001) and of DCP in both the parafovea (P = 0.011) and perifovea (P = 0.001) were significantly lower in the NLR group than in the control group. In a multiple linear regression analysis, the reduced VD of the perifoveal DCP was significantly correlated with the increased international normalized ratio (standardized beta [STD β] = − 0.356; P = 0.047). Conclusions: Macular microvascular changes can be observed during remission from acute leukemia antecedent to clinically visible retinal lesions. Hematological disturbances may be associated with microvascular impairments in preclinical leukemic retinopathy. [ABSTRACT FROM AUTHOR]

As retinitis pigmentosa (RP) is chronic and progressive, the chronological sequence of microvascular changes is important for understanding its pathophysiology. We aimed to investigate retinal and choroidal microvascular changes according to the RP stages. The stages of RP were classified into three stages according to the integrity and width of the inner segment ellipsoid zone: early, ≥ 2500 μm; moderate, < 2500 μm; advanced, absence. Using optical coherence tomography angiography, quantitative microvascular parameters were analyzed. In total, 91 eyes from 49 patients were included. For the superficial capillary plexus (SCP) and deep capillary plexus (DCP), perfusion densities (PDs) in the early stage (SCP: 37.32 ± 8.11%; DCP: 21.19 ± 9.15%) were greater than those in moderate (SCP: 34.16 ± 6.65%, P = 0.011; DCP: 15.67 ± 8.85%, P = 0.031) and advanced stages (SCP: 33.71 ± 9.02%, P = 0.030; DCP: 12.83 ± 6.29%, P < 0.001). The choroidal vascularity index in the early stage (0.58 ± 0.03) was greater than those in the moderate (0.57 ± 0.02, P = 0.017) and advanced stage (0.56 ± 0.02, P = 0.033). The area and perimeter of foveal avascular zone (FAZ) in advanced stage (0.44 ± 0.26 mm2, 2.96 ± 0.86 mm, respectively) were larger than those in early (0.26 ± 0.11 mm2, P = 0.020; 2.19 ± 0.53 mm, P = 0.006, respectively) and moderate stage (0.28 ± 0.13 mm2, P = 0.043; 2.24 ± 0.67 mm, P = 0.013, respectively). During RP disease progression, retinal and choroidal microvascular vessel density decreases in the early stage, followed by FAZ enlargement in the advanced stage. [ABSTRACT FROM AUTHOR]

Purpose: Previous studies have demonstrated functional and structural retinal changes in type 2 diabetes (T2DM). However, less is understood in prediabetes, which is an important precursor to T2DM. Here, we evaluate the microvasculature structure of the foveal avascular zone (FAZ) and how it is correlated with retinal function as measured by the multifocal electroretinogram (mfERG) across levels of glucose dysfunction to uncover how T2DM and prediabetes alter this structure–function relationship. Methods: 33 subjects were included: 9 controls, 12 prediabetes, 12 T2DM with no retinopathy or edema. Subjects were aged 30–70 years, had BCVA of 20/25 or better, and had no confounding ocular conditions. Blood was collected via fingerstick to determine Hemoglobin A1c (HbA1c), which was used along with previous diagnosis, to determine study grouping. Optical coherence tomography angiography (OCTA) was used to analyze the FAZ area and was corrected for refractive error. FAZ area was measured by hand using the Heidelberg Spectralis software. mfERG (VERIS 6.3) metrics implicit time (IT) and amplitude were evaluated in the foveal region, macular region, and averaged over the posterior pole of the right eye. Regression analysis was performed between each study group parameter to determine relationships, and t tests with corrections were used to compare groups. Results: FAZ area (superficial plexus) was negatively correlated with mfERG posterior pole amplitude (p < 0.01, R2 = 0.30), foveal amp (p = 0.02 R2 = 0.17) and macular amplitude (p = 0.02 R2 = 0.18) across all 33 study subjects. FAZ and mfERG metrics were not significantly different between study groups in this cohort except for IT, which was more delayed in the diabetes group compared to other groups. Conclusion: FAZ area is correlated with mfERG amplitudes but not IT. This suggests a link between the structural metrics and retinal function. Longitudinal follow-up work would be helpful to determine the timing of these changes in prediabetes. [ABSTRACT FROM AUTHOR]

Purpose: We investigated the differences in displacement of the outer and inner macular retina toward the optic disc after vitrectomy with internal limiting membrane (ILM) peeling for epiretinal membrane (ERM). Foveal avascular zone (FAZ) area changes were also investigated. Study design: Retrospective observational study Methods: This retrospective observational case series included 45 eyes of 43 patients that underwent vitrectomy with ERM and ILM peeling for ERM and 38 normal eyes. The locations of the centroid of the FAZ (C-FAZ, center of the foveal inner retina) and foveal bulge (center of the foveal outer retina) were determined using 3×3mm superficial optical coherence tomography angiography. C-FAZ and foveal bulge displacements, and the pre- and postoperative FAZ areas and their associated factors, were investigated. Results: Postoperative C-FAZ dislocated significantly more toward the optic disc than in pre-operative or normal eyes (P<0.001). C-FAZ and foveal bulge displaced toward the optic disc after surgery; C-FAZ showed significantly greater displacement than foveal bulge (P<0.001). The pre- and postoperative FAZ areas were correlated (P=0.01). Preoperative FAZ areas ≧0.10mm2 were reduced after surgery, and FAZ areas < 0.10mm2 were increased, independent of foveal displacement. Conclusion: ILM peeling during vitrectomy for ERM caused larger displacement of the inner and smaller displacement of the outer retinas, towards the optic disc. Postoperative changes in the FAZ area were dependent on the baseline FAZ area, but not on the foveal displacement. ILM may physiologically exert centrifugal tractional forces on the fovea. [ABSTRACT FROM AUTHOR]

Purpose: We assessed the relationship between acute primary angle closure glaucoma (APACG) severity and macular microcirculation, as well as the diagnostic ability of blood flow and macular structural parameters on optical coherence tomography angiography (OCTA) for APACG. Methods: APACG patients were assigned to mild, moderate, and severe groups in this cross-sectional study. Age-matched primary angle closure suspect (PACS) and healthy control groups were also recruited. The vessel density (VD) and foveal avascular zone (FAZ) in each macular superficial area were measured using OCTA. The retinal nerve fiber layer thickness (RNFLT) and ganglion cell complex thickness (GCCT) of the corresponding regions were measured using OCT. Results: All parameters in the control, PACS, and mild APACG groups differed significantly from those in the moderate and severe APACG groups (all P < 0.05). VD and RNFLT showed high and moderate diagnostic ability, respectively, to distinguish moderate APACG from PACS, with significant differences (P < 0.05) in areas under the receiver operating characteristic curve (AUCs) for VD and RNFLT in six macular areas. The diagnostic abilities of VD and RNFLT for distinguishing severe APACG from PACS were increased, with significant differences in the AUCs for VD and RNFLT in five macular areas (P < 0.05). All macular VDs and GCCTs were similar among the three APACG groups (P > 0.05). Conclusions: Damage to the VD and FAZ in the macula increased with APACG severity. VD in the macular superficial layer showed a higher diagnostic ability than RNFLT, which was equivalent to that of GCCT. [ABSTRACT FROM AUTHOR]

Purpose: Analysis of foveal avascular zone (FAZ) width and vascular density (VD) changes before and after intravitreal dexamethasone implant (IDI) treatment in diabetic macular edema (DME) patients resistant to anti-VEGF treatment. Methods: In this retrospective study, patients who were regularly treated with at least 5 doses of intravitreal Anti-VEGF (bevacizumab, ranibizumab or aflibercept) for DME and whose DME continued were considered resistant to Anti-VEGF and were treated with IDI for the first time. Thirty-four eyes of 34 patients were included in the study. FAZ and VD values of optical coherence tomography angiography (OCT-A) scans at 0, 1 and 3 months were examined. Results: In OCT-A measurements, the pre-IDI superficial plexus FAZ (SFAZ) area (0.350 ± 0.120 mm2) was decreased at 1 (0.292 ± 0.132 mm2, p < 0.001) and at 3 months (0.311 ± 0.153 mm2, p = 0.017). Pre-IDI deep plexus FAZ (DFAZ) area (0.651 ± 0.313 mm2) was decreased at 1-month post-IDI (0.481 ± 0.247 mm2, p < 0.001) while no significant change was observed at 3 months (0.575 ± 0.259 mm2, p = 0.197). There was no significant change in the mean post-IDI total VD rate in both superficial (pre 39.2% ± 2.4; 1st month 39.2% ± 2.6%; 3rd month 39.5% ± 3.4%) and deep retinal plexus (pre 43.3% ± 2.6%; 1st month 43.5 ± 2.8%; 3rd month 43.6% ± 4.6%) (p = 0.408 and p = 0.607, respectively). Conclusion: The study showed that IDI caused a significant decrease in the FAZ area without any change in VD in patients with DME resistant to the anti-VEGF agents. IDI might be related to a decrease in the macular ischemia secondary to diabetic retinopathy. [ABSTRACT FROM AUTHOR]

Aim: To analyse the alterations in retino-choroidal angioarchitecture in eyes with active tubercular serpiginous-like choroiditis (TB-SLC) using swept-source optical coherence tomography angiography (SS-OCTA). Methods: This prospective cross-sectional study enrolled 34 eyes diagnosed with TB-SLC and 34 age-matched healthy controls. Data acquisition with SS-OCTA using the PLEX Elite 9000 (Carl Zeiss Meditec Inc., Dublin, CA, USA) with a 6 × 6 mm pattern centered on the foveal center was done. Automated retinal vessel length density (VLD) and perfusion density (PD) and foveal avascular zone architecture were obtained from the ARI hub. Choroidal vascularity index (CVI) and choriocapillaris flow deficits (CCFD) were obtained using Image J. Results: Eyes with TB-SLC showed significantly reduced vessel indices in all retinal layers (P < 0.05), decreased CVI (P = 0.001) and increased CCFD (P = 0.001) as compared to healthy eyes. CCFD was increased significantly in the involved quadrants in eyes with TB-SLC when compared with the uninvolved quadrants and corresponding healthy quadrants in control subjects. CCFD showed a significant negative correlation with visual acuity (r = − 0.46, P = 0.006). Conclusion: Eyes with TB-SLC manifest reduced VLD and PD, decreased CVI and increased CCFD. The CCFD alterations are non-uniform in these eyes, mainly located under the regions with disease activity. [ABSTRACT FROM AUTHOR]

Aim: Since its relevance on diagnosis and prognosis of diabetic retinopathy (DR), this review will examine a multimodal imaging approach to detect diabetic macular ischemia (DMI). Methods: A PubMed engine search was carried out using the term "macular ischemia" paired with "diabetes," and "diabetic macular ischemia" paired to "fluorescein angiography," "ultra-wide field fluorescein angiography," "optical coherence tomography angiography," "octa," "2D octa," "ultra-wide field octa," "3D octa," "visual acuity." All studies published in English up to October 2021 irrespective of their publication status were reviewed, and relevant publications were included in this review. Results: Recently, new technologies have been proposed as an alternative to fluorescein angiography (FA), which is an actual diagnostic gold standard technique. Nowadays, optical coherence tomography angiography (OCTA) has emerged as the most promising and reliable procedure able to provide a qualitative and quantitative description of DMI. Newer three-dimensional (3D) OCTA approach will be discussed too. Moreover, we will discuss how OCTA might identify preclinical alterations before the onset of DR and allow prediction about the progression of disease. Conclusion: OCTA has significantly expanded our knowledge on diabetic macular ischemia. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the changes in posterior segment hemodynamics caused by horizontal rectus muscle surgeries using the optic coherence tomography angiography (OCTA).Patients who underwent at least one horizontal rectus recession, resection, or combination surgery were included. The patients were evaluated with an OCTA preoperatively and 30 days postoperatively. Postoperative changes in superficial capillary plexus (SCP)-vessel density (VD), deep capillary plexus (DCP)-VD, foveal avascular zone (FAZ) area and choriocapillaris (CC)-flow area parameters were examined. The mean differences (Δ) for the parameters in which significant changes were detected in the whole operated eyes group were compared between the single- and two-muscle surgery groups.Twenty-five eyes of 24 patients with an average age of 16.40 ± 6.75 years (5–29) were included. Of the eyes, 10 underwent single muscle recession surgery. Two-muscle surgeries were performed in 15 eyes. SCP-VD in the superior parafoveal region increased significantly postoperatively (53.23 ± 4.11% vs. 54.54 ± 3.67%, p = 0.032). For DCP-VD, there was a statistically significant increase in all zones, except the superior hemisphere and fovea regions (p < 0.05 for all). FAZ area did not change significantly (p = 0.207). There was a significant increase in the CC-flow area (2.171 ± 0.146 mm2 vs. 2.232 ± 0.115 mm2, p = 0.013). There was a significant difference between the two groups only for the Δ SCP-VD/parafovea superior value (-0.62 ± 0.98 vs. 1.57 ± 3.07, p = 0.019).Conventional horizontal rectus muscle surgeries may cause alterations in posterior segment hemodynamics. The number of muscles incised does not seem to greatly affect the magnitude of changes that occur.What is known• After conventional horizontal rectus muscle surgeries, the anterior ciliary arteries are not recanalized, instead, anterior segment blood flow is maintained by increasing the flow in the long posterior ciliary arteries.• Previous studies using Doppler ultrasonography have shown increased flow in the ophthalmic artery, central retinal artery and long posterior ciliary arteries.What is new• In this study, significant increases were observed in superficial and deep capillary plexus-vessel density and choriocapillaris-flow area parameters in the first postoperative month with optic coherence tomography angiography device.• Hemodynamic increases in both retinal and choroidal vasculature were detected in the early period after conventional horizontal rectus muscle surgeries.• The number of muscles incised does not seem to greatly affect the magnitude of changes that occur.Methods: To investigate the changes in posterior segment hemodynamics caused by horizontal rectus muscle surgeries using the optic coherence tomography angiography (OCTA).Patients who underwent at least one horizontal rectus recession, resection, or combination surgery were included. The patients were evaluated with an OCTA preoperatively and 30 days postoperatively. Postoperative changes in superficial capillary plexus (SCP)-vessel density (VD), deep capillary plexus (DCP)-VD, foveal avascular zone (FAZ) area and choriocapillaris (CC)-flow area parameters were examined. The mean differences (Δ) for the parameters in which significant changes were detected in the whole operated eyes group were compared between the single- and two-muscle surgery groups.Twenty-five eyes of 24 patients with an average age of 16.40 ± 6.75 years (5–29) were included. Of the eyes, 10 underwent single muscle recession surgery. Two-muscle surgeries were performed in 15 eyes. SCP-VD in the superior parafoveal region increased significantly postoperatively (53.23 ± 4.11% vs. 54.54 ± 3.67%, p = 0.032). For DCP-VD, there was a statistically significant increase in all zones, except the superior hemisphere and fovea regions (p < 0.05 for all). FAZ area did not change significantly (p = 0.207). There was a significant increase in the CC-flow area (2.171 ± 0.146 mm2 vs. 2.232 ± 0.115 mm2, p = 0.013). There was a significant difference between the two groups only for the Δ SCP-VD/parafovea superior value (-0.62 ± 0.98 vs. 1.57 ± 3.07, p = 0.019).Conventional horizontal rectus muscle surgeries may cause alterations in posterior segment hemodynamics. The number of muscles incised does not seem to greatly affect the magnitude of changes that occur.What is known• After conventional horizontal rectus muscle surgeries, the anterior ciliary arteries are not recanalized, instead, anterior segment blood flow is maintained by increasing the flow in the long posterior ciliary arteries.• Previous studies using Doppler ultrasonography have shown increased flow in the ophthalmic artery, central retinal artery and long posterior ciliary arteries.What is new• In this study, significant increases were observed in superficial and deep capillary plexus-vessel density and choriocapillaris-flow area parameters in the first postoperative month with optic coherence tomography angiography device.• Hemodynamic increases in both retinal and choroidal vasculature were detected in the early period after conventional horizontal rectus muscle surgeries.• The number of muscles incised does not seem to greatly affect the magnitude of changes that occur.Results: To investigate the changes in posterior segment hemodynamics caused by horizontal rectus muscle surgeries using the optic coherence tomography angiography (OCTA).Patients who underwent at least one horizontal rectus recession, resection, or combination surgery were included. The patients were evaluated with an OCTA preoperatively and 30 days postoperatively. Postoperative changes in superficial capillary plexus (SCP)-vessel density (VD), deep capillary plexus (DCP)-VD, foveal avascular zone (FAZ) area and choriocapillaris (CC)-flow area parameters were examined. The mean differences (Δ) for the parameters in which significant changes were detected in the whole operated eyes group were compared between the single- and two-muscle surgery groups.Twenty-five eyes of 24 patients with an average age of 16.40 ± 6.75 years (5–29) were included. Of the eyes, 10 underwent single muscle recession surgery. Two-muscle surgeries were performed in 15 eyes. SCP-VD in the superior parafoveal region increased significantly postoperatively (53.23 ± 4.11% vs. 54.54 ± 3.67%, p = 0.032). For DCP-VD, there was a statistically significant increase in all zones, except the superior hemisphere and fovea regions (p < 0.05 for all). FAZ area did not change significantly (p = 0.207). There was a significant increase in the CC-flow area (2.171 ± 0.146 mm2 vs. 2.232 ± 0.115 mm2, p = 0.013). There was a significant difference between the two groups only for the Δ SCP-VD/parafovea superior value (-0.62 ± 0.98 vs. 1.57 ± 3.07, p = 0.019).Conventional horizontal rectus muscle surgeries may cause alterations in posterior segment hemodynamics. The number of muscles incised does not seem to greatly affect the magnitude of changes that occur.What is known• After conventional horizontal rectus muscle surgeries, the anterior ciliary arteries are not recanalized, instead, anterior segment blood flow is maintained by increasing the flow in the long posterior ciliary arteries.• Previous studies using Doppler ultrasonography have shown increased flow in the ophthalmic artery, central retinal artery and long posterior ciliary arteries.What is new• In this study, significant increases were observed in superficial and deep capillary plexus-vessel density and choriocapillaris-flow area parameters in the first postoperative month with optic coherence tomography angiography device.• Hemodynamic increases in both retinal and choroidal vasculature were detected in the early period after conventional horizontal rectus muscle surgeries.• The number of muscles incised does not seem to greatly affect the magnitude of changes that occur.Conclusions: To investigate the changes in posterior segment hemodynamics caused by horizontal rectus muscle surgeries using the optic coherence tomography angiography (OCTA).Patients who underwent at least one horizontal rectus recession, resection, or combination surgery were included. The patients were evaluated with an OCTA preoperatively and 30 days postoperatively. Postoperative changes in superficial capillary plexus (SCP)-vessel density (VD), deep capillary plexus (DCP)-VD, foveal avascular zone (FAZ) area and choriocapillaris (CC)-flow area parameters were examined. The mean differences (Δ) for the parameters in which significant changes were detected in the whole operated eyes group were compared between the single- and two-muscle surgery groups.Twenty-five eyes of 24 patients with an average age of 16.40 ± 6.75 years (5–29) were included. Of the eyes, 10 underwent single muscle recession surgery. Two-muscle surgeries were performed in 15 eyes. SCP-VD in the superior parafoveal region increased significantly postoperatively (53.23 ± 4.11% vs. 54.54 ± 3.67%, p = 0.032). For DCP-VD, there was a statistically significant increase in all zones, except the superior hemisphere and fovea regions (p < 0.05 for all). FAZ area did not change significantly (p = 0.207). There was a significant increase in the CC-flow area (2.171 ± 0.146 mm2 vs. 2.232 ± 0.115 mm2, p = 0.013). There was a significant difference between the two groups only for the Δ SCP-VD/parafovea superior value (-0.62 ± 0.98 vs. 1.57 ± 3.07, p = 0.019).Conventional horizontal rectus muscle surgeries may cause alterations in posterior segment hemodynamics. The number of muscles incised does not seem to greatly affect the magnitude of changes that occur.What is known• After conventional horizontal rectus muscle surgeries, the anterior ciliary arteries are not recanalized, instead, anterior segment blood flow is maintained by increasing the flow in the long posterior ciliary arteries.• Previous studies using Doppler ultrasonography have shown increased flow in the ophthalmic artery, central retinal artery and long posterior ciliary arteries.What is new• In this study, significant increases were observed in superficial and deep capillary plexus-vessel density and choriocapillaris-flow area parameters in the first postoperative month with optic coherence tomography angiography device.• Hemodynamic increases in both retinal and choroidal vasculature were detected in the early period after conventional horizontal rectus muscle surgeries.• The number of muscles incised does not seem to greatly affect the magnitude of changes that occur.: To investigate the changes in posterior segment hemodynamics caused by horizontal rectus muscle surgeries using the optic coherence tomography angiography (OCTA).Patients who underwent at least one horizontal rectus recession, resection, or combination surgery were included. The patients were evaluated with an OCTA preoperatively and 30 days postoperatively. Postoperative changes in superficial capillary plexus (SCP)-vessel density (VD), deep capillary plexus (DCP)-VD, foveal avascular zone (FAZ) area and choriocapillaris (CC)-flow area parameters were examined. The mean differences (Δ) for the parameters in which significant changes were detected in the whole operated eyes group were compared between the single- and two-muscle surgery groups.Twenty-five eyes of 24 patients with an average age of 16.40 ± 6.75 years (5–29) were included. Of the eyes, 10 underwent single muscle recession surgery. Two-muscle surgeries were performed in 15 eyes. SCP-VD in the superior parafoveal region increased significantly postoperatively (53.23 ± 4.11% vs. 54.54 ± 3.67%, p = 0.032). For DCP-VD, there was a statistically significant increase in all zones, except the superior hemisphere and fovea regions (p < 0.05 for all). FAZ area did not change significantly (p = 0.207). There was a significant increase in the CC-flow area (2.171 ± 0.146 mm2 vs. 2.232 ± 0.115 mm2, p = 0.013). There was a significant difference between the two groups only for the Δ SCP-VD/parafovea superior value (-0.62 ± 0.98 vs. 1.57 ± 3.07, p = 0.019).Conventional horizontal rectus muscle surgeries may cause alterations in posterior segment hemodynamics. The number of muscles incised does not seem to greatly affect the magnitude of changes that occur.What is known• After conventional horizontal rectus muscle surgeries, the anterior ciliary arteries are not recanalized, instead, anterior segment blood flow is maintained by increasing the flow in the long posterior ciliary arteries.• Previous studies using Doppler ultrasonography have shown increased flow in the ophthalmic artery, central retinal artery and long posterior ciliary arteries.What is new• In this study, significant increases were observed in superficial and deep capillary plexus-vessel density and choriocapillaris-flow area parameters in the first postoperative month with optic coherence tomography angiography device.• Hemodynamic increases in both retinal and choroidal vasculature were detected in the early period after conventional horizontal rectus muscle surgeries.• The number of muscles incised does not seem to greatly affect the magnitude of changes that occur. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the changes in retinal microvasculature in eyes with anterior uveitis (AU) using optical coherence tomography angiography. Methods: Foveal avascular zone (FAZ) of superficial capillary plexus (SCP) and deep capillary plexus (DCP), vessel density (VD) of SCP, DCP, and choriocapillaris, and central macular thickness (CMT) and central foveal thickness (CFT) were calculated from 34 healthy and 41 uveitic eyes. The parameters were compared between the two groups. Results: The deep FAZ was significantly smaller in the eyes with AU during the attack than after recovery and the control group (p = 0.001 and p = 0.003, respectively). The VD in deep capillary plexus (DCP) in eyes with AU during the attack was significantly higher than the control group (p = 0.048). The VD in the foveal sector of DCP in eyes with AU during the attack and after recovery was significantly higher than the control group (p = 0.001 and p = 0.031, respectively). There was no significant difference regarding CMT, CFT, VDs of each segment and each sector, and superficial and deep FAZ between eyes with first uveitis attack and those with recurrent uveitis during the attack and after recovery (p > 0.05). Conclusion: The results of this study show that there is a reduction in the FAZ and an increase in the VD of the DCP of the retina during active AU, and these findings are reversible. Acute AU may affect the macular microvasculature, which is usually temporary, especially in the DCP. [ABSTRACT FROM AUTHOR]

Introduction: To review the existing literature about the optical coherence tomography angiography (OCTA) findings regarding peripapillary and macular vessel density (VD) in patients with pseudoexfoliative glaucoma (PXG). Methods: A comprehensive search of the PubMed database was conducted to include articles up to November 1, 2021, using an appropriate search algorithm. The retrieved articles were assessed for eligibility and filtered manually to exclude duplicates, while articles and book chapters cited in the reference lists of the eligible articles obtained by this method were reviewed so as not to miss any relevant studies. Results: There is consistency among the studies published so far that a significant decrease in peripapillary VD exists in eyes with PXG compared to controls, and macular VD has also been reported to be significantly lower in PXG eyes than controls. However, the existing literature remains controversial regarding OCTA findings in eyes with PXG compared to those with primary open-angle glaucoma (POAG). Several studies have found that peripapillary VD and macular VD were significantly lower in PXG than POAG, while other studies reported no significant difference. Conclusions: Eyes with PXG were found to present decreased peripapillary and macular VD compared to control eyes, suggesting that a vascular component, including optic nerve hypoperfusion, may be implicated in the pathogenesis of PXG. [ABSTRACT FROM AUTHOR]

Using optical coherence tomography angiography (OCTA), we sought to evaluate parafoveal vascular density (VD) in patients with central serous chorioretinopathy (CSCR). Our study included 43 patients with a diagnosis of CSCR and 40 healthy controls. Ophthalmologic examination findings and OCTA measurements of the participants were retrospectively analysed. Of the 43 patients with CSCR, 31 were males (72%) and 12 were females (28%); the control group was 30 males (75%) and 10 females (25%) (p = 0.657). There were significant differences between affected eyes, unaffected eyes and healthy control eyes for all parameters in the superficial capillary plexus (SCP) VD and deep capillary plexus (DCP) VD (p < 0.05 for all values). It was also determined that the affected eyes had lower SCP-VD and DCP-VD than the unaffected eyes and that the unaffected eyes had lower SCP-VD and DCP-VD than the healthy control eyes (p < 0.05 for all values). While there were no significant differences in the deep foveal avascular zone (FAZ) area, the superficial FAZ area was larger in affected eyes than in both unaffected eyes and healthy control eyes (p < 0.05). In most areas, the SCP-VD and DCP-VD values were lower and the FAZ larger in the chronic group than in the acute group (p < 0.05). Retinal vascular changes were found in patients with both acute and chronic CSCR, and the fellow eyes of these patients were also affected. OCTA can therefore be considered an easily applicable, non-invasive screening option for evaluating the microvascular structure in these patients. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the quantitative differences in optical coherence tomography angiography (OCTA) data between type 2 diabetes patients without clinically detectable diabetic retinopathy (DR) and healthy subjects. Methods: Thirty-nine patients with type 2 diabetes without DR and 41 age- and sex-matched healthy controls were recruited. The vessel density and foveal avascular zone (FAZ) area in the superficial capillary plexus and deep capillary plexus were measured using Nidek RS-3000 Advance® and compared between patient cohorts. Foveal vessel density (%) and FAZ (%) were also calculated. Results: A significant decrease in vessel density has been observed in the deep capillary plexus of the patients compared to healthy individuals (5.58 ± 0.98 mm2 versus 6.15 ± 0.89 mm2, p < 0.001). However, there were no significant differences in other parameters between cohorts (p > 0.05 in all parameters). Despite the decrease of deep capillary plexus density in the macular region, there was no significant change observed in foveal vessel density (p:0.44). It has also been observed that the duration of diabetes mellitus correlates with vessel density decrease in deep capillary plexus (R:–0.52; p < 0.001). In both groups, all parameters in deep capillary plexus were significantly higher than superficial capillary plexus (p < 0.001 for all parameters). Conclusions: OCTA can identify quantitative changes in DCP before the manifestation of clinically apparent retinopathy. DCP-VD reduction may be an earlier finding than FAZ enlargement. Despite the reduction of VD, FVD could be preserved for a certain period of time in DM patients. [ABSTRACT FROM AUTHOR]

Purposes: To quantitatively evaluate the vessel density of macular microvasculature, choriocapillary, and foveal avascular zone (FAZ) in both eyes of patients with unilateral retinal vein occlusion (RVO) using the optical coherence tomography angiography (OCTA) compared with the normal controls. Methods: A retrospective review was conducted on 72 patients with unilateral RVO (72 eyes with RVO and 72 RVO fellow eyes) and 72 healthy individuals (72 normal control eyes). The 3 × 3 mm macular angiogram was acquired using the OCTA. The vessel densities of the retinal superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillary plexus (CCP) were measured, and FAZ was quantified. Results: The RVO eyes compared to their fellow eyes, and the fellow eyes compared to the normal controls, showed a significantly lower vessel density in both the SCP and DCP in the whole image and parafovea (P < 0.05) and the CCP (P < 0.05), except for the foveal region (P > 0.05). No significant differences between the RVO eyes and the fellow eyes in the FAZ area and perimeter (P > 0.05) were observed, while the acircularity index in the RVO eyes was significantly higher than the fellow eyes (P < 0.05). Additionally, the FD-300 in the RVO eyes was significantly lower than their fellow eyes (P < 0.05). Conclusions: The OCTA reveals that the macular microvasculature of the RVO fellow eyes can be impaired in both the superficial and deep retinal layer as well as the choriocapillary, suggesting the influence of systemic factors in the development of RVO. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the spatial relationship between macular superficial vessel density (SVD) and macular ganglion cell-inner plexiform layer (GCIPL) thickness in primary angle closure glaucoma (PACG), and to investigate diagnostic abilities of macular SVD and foveal avascular zone (FAZ) parameters. Methods: This was a cross-sectional study on 38 PACG patients (38 eyes) and 25 healthy subjects (25 eyes). Macular region was imaged using a 1050-nm-wavelength swept-source optical coherence tomography (OCT) angiography (OCTA) system (DRI OCT Triton, TOPCON). Vessel density of the macular region was quantified by ImageJ software. The peripapillary retinal nerve fiber layer (pRNFL) thicknesses and macular GCIPL thickness were obtained by swept-source OCT. Pearson correlation analysis was used to evaluate the spatial positional relationship between macular SVD and macular GCIPL thickness. At the same time, the correlation between macular SVD and pRNFL thickness was evaluated. Areas under the receiver operating characteristics curves (AUCs) of OCT, OCTA and FAZ measurement metrics were calculated to assess the diagnostic ability for glaucoma. Results: Macular GCIPL thickness had a moderate correlation with the macular SVD in the inferonasal sector (r = 0.426, P = 0.008). In addition, there was a strong correlation between inferonasal sector of macular vessel density and 5,6,7,8 clock-hour regions of the pRNFL thicknesses (all r > 0.5). Inferoinferior sector of macular SVD and 6,7 clock-hour regions of pRNFL thicknesses also had strong correlation (all r > 0.5). The AUCs of macular SVD ranged between 0.61 (superonasal sector) and 0.76 (inferoinferior sector). The FAZ circularity index showed the highest diagnostic power (AUC = 0.94;95% CI, 0.85–0.99), followed by superotemporal sector of macular GCIPL thicknesses (0.93;95% CI,0.83–0.98). Conclusions: Sector of macular SVD not only had a spatial positional correlation with corresponding macular GCIPL thickness, but also with clock-hour regional pRNFL thicknesses in PACG eyes. FAZ circulation index might be a useful diagnostic parameter. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the retinal microvascular and choroidal thickness changes in eyes with active Behḉet's disease posterior uveitis and post-remission. Patients and methods: A prospective longitudinal observational analytic study where patients with active Behḉet's posterior uveitis (BU) were assessed by optical coherence tomography angiography (OCTA) and enhanced depth imaging OCT during activity and after remission, for retinal microvascular and subfoveal choroidal thickness (SFCT) changes. Results: 26 eyes of 20 patients were included. With remission of active posterior uveitis, capillary density in both layers increased, only being significant in the superficial capillary plexus (SCP) 1.81 ± 3.57% (p = 0.025), while the foveal avascular zone (FAZ) area increased by 0.036 ± 0.069 mm (p = 0.023). Conclusion: OCTA can be used to monitor the activity of Behḉet's posterior uveitis. Comparing the retinal microvascular changes during activity and after remission, the superficial capillary plexus was found to be more indicative of the activity status, while the deep capillary plexus and foveal avascular zone area—being more irreversible—are more useful as prognostic indicators. Subfoveal choroidal thickness, on the other hand, proved to be a consistent indictor of visual function; however, its change doesn't accurately reflect the activity status. [ABSTRACT FROM AUTHOR]

Purpose: In this study, we aimed to determine the alterations in the retina and peripapillary vascular density in patients with vitamin B12 deficiency. Material and method: The patients were divided into two groups regarding their vitamin B12 levels as the low vitamin B12 group (< 200 pg/ml) and the normal vitamin B12 group (≥ 200 pg/ml). The retinal nerve fiber layer thickness (RNFLT) and the central macular thickness (CMT) were measured through an SD-OCT analysis. The foveal avascular zone (FAZ), vessel density (VD) of the superficial capillary plexus (SCP), and deep capillary plexus (DCP) of the macula, and the VD of the radial peripapillary capillary plexus (RPCP) for the optic disk were determined by OCT-A. Results: Thirty-three patients were in the low vitamin B12 group and 54 were in the normal group. The mean RNFLT measurements were significantly lower in the low vitamin B12 group (p = 0.001). The RPCP values in all quadrants were significantly lower in the patients with vitamin B12 deficiency (p = 0.001); moreover, there was a significant increase in the FAZ value with a decrease in both superficial (p = 0.001) and deep (p = 0.001) VDs. There was a significant positive correlation between the serum vitamin B12 levels and the RPCP values and superficial and deep VDs, while the FAZ value was negatively correlated with the vitamin B12 levels. Conclusion: Vitamin B12 deficiency has diverse effects on ocular structures and retinal vasculature. Decreased VDs and increased FAZ may be associated with severe ocular alterations in the long term, which should be further investigated. [ABSTRACT FROM AUTHOR]

Purpose: To describe the foveal avascular zone (FAZ) and vessel density (VD) in the superficial and deep capillary plexus in children with a history of prematurity on optical coherence tomography angiography (OCTA) and their correlation with gestational age (GA) and birth weight (BW). Methods: We enrolled 81 preterm- and eight term-born children in this prospective observational study. The Optovue RTVue AVANTI (Optovue Inc., Fremont, CA) was used to procure the OCTA images. The 3 × 3 mm scan protocol centered on the fovea and the central 1 mm of the grid along with the FAZ of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) was acquired. Results: The mean SCP-VD was comparable between the preterms and term controls (p = 0.315) in the central fovea (1-mm grid). However, the SCP-VD of the 3-mm grid was lower in the preterms born without ROP, with type 1 ROP, and with type 2 ROP (47.61, 47.90, and 48.82 respectively) compared to that in the term group (51.38; p = 0.031). The FAZ in the SCP (p = 0.003) and DCP (p = 0.003) was significantly smaller in the preterms compared to that in the controls. Based on the GA sub-analysis, the FAZ was significantly smaller in the SCP and DCP of preterms born < 31 weeks and > 31 weeks GA (p < 0.000, p < 0.035, respectively). Based on the BW, the difference between the FAZ in the SCP (p = 0.002) and DCP (p = 0.003) was significant. There was no association between the visual acuity and FAZ. Conclusion: Optical coherence tomography angiography findings in this study show an altered foveal morphology and vascularity in preterms with and without ROP. [ABSTRACT FROM AUTHOR]

Purpose: Report the foveal avascular zone (FAZ) area imaged by OCT angiography (OCTA) using a full spectrum probabilistic algorithm in eyes of healthy individuals from Costa Rica without any ocular or systemic pathology. Methods: Retrospective chart review of consecutive healthy patients that were evaluated from January 2018 to October 2018 that underwent OCTA of the macular area. The OCTA consisted of a 10° × 10° cube of 512 A scans separated by 6 µm each with an automated real time mode of 5. The FAZ area of the superficial vascular complex (SVC), the deep vascular complex (DVC), superficial vascular plexus (SVP), intermediate vascular plexus (IVP) and the deep vascular plexus (DVP) were measured manually by 2 different observers at 3 different times. Results: A total of 234 eyes of 121 patients were included in this study. Mean age was 50 years (range, 15–89), 85 patients (70%) were female. Inter- and intra-observer agreements were excellent. The mean FAZ areas in the different layers were 0.258 ± 0.0035 mm2 for the SVC, 0.205 ± 0.01 mm2 for the DVC, 0.415 ± 0.01 mm2 for the SVP, 0.305 ± 0.01 mm2 for the ICP and 0.420 ± 0.01 mm2 for the DCP. The mean FAZ areas in most of the measured layers increased with age and decreased with CMT. Gender and spherical equivalence were not correlated with FAZ area. Conclusion: Manual measurements of the FAZ imaged by OCT-A using a full spectrum probabilistic algorithm are widely reproducible both by the same observer and between observers. The FAZ increases with age and decreases with CMT in normal individuals. [ABSTRACT FROM AUTHOR]

Purpose: To compare retinal capillary plexus vessel densities, choroidal thickness, optic disc vessel densities and foveal avascular zone measurements between normal subjects and subjects with obstructive sleep apnea syndrome (OSAS) using spectral-domain OCT angiography (OCTA). Methods: Forty eyes of patients with overall OSAS, 20 eyes of patients with mild-moderate OSAS, 20 eyes of patients with severe OSAS on polysomnography and 21 controls were evaluated with the RTVue-XR Avanti OCTA (Optovue, Inc., Fremont, CA). Superficial and deep retinal capillary plexus vessel densities, choroidal thickness and foveal avascular zone (FAZ) parameters (area, diameter, acircularity index of the FAZ, foveal density-300) were measured for all subjects. Results: Superficial capillary plexus vessel densities of the groups were similar. Deep capillary plexus (DCP) vessel densities of all three OSAS groups decreased in the parafoveal region (< 0.001). In the perifoveal region, DCP vessel densities were decreased in the Overall OSAS group (p = 0.023) and in the Severe OSAS group (p = 0.021), whereas it was similar in the Mild-moderate OSAS group. Choroidal thickness decreased in all three OSAS groups (p < 0.001). All FAZ measurements and foveal density-300 measurements were similar compared to the control group. Conclusion: Our findings indicate that in severe OSAS patients, deep parafoveal, perifoveal vascular densities decrease and the choroid layer becomes thinner. When evaluating a patient with OSAS, it should be kept in mind that there may be eye involvement due to the disease. [ABSTRACT FROM AUTHOR]

Purpose: The primary aim of our study was to evaluate retinal microvascular anomalies recorded with optical coherence tomography angiography (OCTA) and the retinal metabolic function measured with retinal oximetry (RO) in patients with retinitis pigmentosa (RP). The secondary aim of the study was to link the presence of macular edema to microvascular and metabolic parameters in RP. Methods: OCTA and RO were performed on 94 eyes: 64 eyes diagnosed with RP with (ME-RP) and without (no-ME-RP) macular edema were compared with 30 control eyes. Study end points were as follows: mean superficial (FAZ-S) and deep foveal avascular zone (FAZ-D) determined by OCTA. In addition, we evaluated the mean arterial (A-SO2; %), venular (V-SO2; %) oxygen saturation, their difference (A-V SO2; %), as well as the corresponding mean diameter of the retinal arterioles (D-A; μm) and venules (D-V; μm). Results: RP patients differed from controls by enlarged FAZ-S and FAZ-D (p ≤ 0.001), attenuated retinal vessels (p ≤ 0.001), and increased retinal vessel oxygen saturation (p ≤ 0.010). Subgroup analyses within RP patients revealed more pronounced alterations of microvascular parameters and metabolic function in the presence of macular edema. In the no-ME-RP subgroup, significant interactions were present between FAZ-S, A-SO2, and V-SO2, whereas in the ME-RP subgroup, we found significant correlations between FAZ-D and D-A. Conclusion: A combined microvascular structure–metabolic function approach enhances our understanding of inherited retinal diseases. The presence of macular edema in RP seems to be a result of more altered microvascular–metabolic function. Macular edema should thus be taken into consideration when evaluating microvascular and/or metabolic changes in RP. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the fovea in nanophthalmic eyes using spectral domain optical coherence tomography (SD-OCT) and OCT angiography (OCTA), and to investigate the relationship between the macular microstructure and visual acuity. Methods: This is a retrospective case series of five nanophthalmic patients. The foveal avascular zone (FAZ) area was measured in superficial and deep vascular layers with OCTA. The thickness of the inner retinal layer (IRL) was measured with SD-OCT. The ratio of the foveal and parafoveal IRL thickness (fIRL/pIRL ratio) was calculated. The relationship between these parameters and visual acuity was then investigated. Results: Eight eyes were identified as nanophthalmic with a mean axial length of 17.19 ± 1.44 mm (range: 15.71 to 19.88 mm). The mean best-corrected visual acuity (BCVA) in the logarithm of the minimum angle of resolution (logMAR) was 0.12 ± 0.18 (range: − 0.18 to 0.40). OCTA showed that FAZs were either absent or undeveloped in the superficial and deep capillary plexuses. Two patients did not show any visual impairments despite small FAZ and a shallow foveal depression. Although the BCVA was significantly correlated with the deep FAZ size, it did not correlate with the superficial FAZ size, axial length, or fIRL/pIRL ratio. However, the refractive error, axial length, and deep FAZ size were all significantly correlated with the fIRL/pIRL ratio. Conclusions: The FAZs were commonly found to be small in the superficial and deep capillary plexuses. Although the deep FAZ size correlated with visual acuity, it is unclear whether the retinal microstructure and the FAZ size are responsible for the visual impairments observed in the same individuals. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the early macular microvascular alterations in patients with type 1 and 2 diabetes mellitus (DM) without diabetic retinopathy (DR), using optical coherence tomography angiography (OCT-A), and compare these with nondiabetic patients. Methods: This prospective study involved 93 patients with type 1 diabetes (DM1), 104 patients with type 2 diabetes (DM2) without signs of DR, and 71 healthy subjects for the control group. The foveal avascular zone (FAZ) area and the vessel density (VD) at the superficial capillary plexus (SCP) and deep capillary plexus (DCP) were evaluated. Results: The SCP and DCP FAZ areas were significantly larger in the DM1 group in comparison with the controls (p =.001), while no significant differences were observed between the DM2 group and the healthy control group (p =.12). Additionally, no significant differences in FAZ area were found between the DM1 and DM2 groups (p =.26). The VD was significantly reduced in DM1 and DM2 groups compared to controls. A direct correlation was found between the duration of diabetes and SCP FAZ area (r = 0.44; R2 = 0.19; p =.0001). Statistically significant differences in the FAZ area at SCP and DCP were observed when comparing patients with a diabetes duration > 10 years and < 10 years in the DM2 group (p =.0001, respectively) and only in the FAZ area at the DCP in the DM1 group (p =.0001). Conclusion: Diabetic patients without DR demonstrate early microvascular alteration in the macular area on OCT-A, which is more pronounced in type I DM, and correlates with the duration of the disease. [ABSTRACT FROM AUTHOR]

Purpose: This study searched for early predictive vascular biomarkers for visual outcomes in eyes with macular edema caused by branch retinal vein occlusion (BRVOME). Methods: Twenty-four eyes of 24 subjects with BRVOME were treated with the intravitreal injection of ranibizumab (IVR) for at least 6 months. We measured mean blur rate (MBR) in the optic nerve head (ONH) and vessel density (VD) in the macula with laser speckle flowgraphy and optical coherence tomography angiography, respectively. Results: Six-month post-IVR best-corrected visual acuity (BCVA) was correlated positively with age, pre-IVR BCVA, 1-month post-IVR BCVA, 3-month post-IVR BCVA and pre-IVR systolic blood pressure (P < 0.001, P < 0.001, P < 0.001, P < 0.001 and P = 0.02, respectively) and negatively with pre-IVR overall MBR, 1-month post-IVR overall MBR, 6-month post-IVR overall MBR, 3-month post-IVR deep retinal capillary plexus (DCP) VD and 6-month post-IVR DCP VD (P = 0.03, P = 0.03, P = 0.02, P = 0.01 and P = 0.005, respectively). Furthermore, a multiple regression analysis showed that pre-IVR overall MBR (β = − 0.67, P = 0.009) was among independent prognostic factors predicting 6-month post-IVR BCVA. Six-month post-IVR DCP VD was also correlated with overall MBR at all time points. Conclusion: ONH blood flow may be a pre-IVR biomarker of both visual outcomes and post-IVR deep macular microcirculation in eyes with BRVOME. [ABSTRACT FROM AUTHOR]

Background: The aim of the study was to investigate whether retinal neurovascular structural impairment in children and adolescents with type 1 diabetes mellitus (T1D) without clinical signs of diabetic retinopathy (DR) could be detected early via optical coherence tomography (OCT) and OCT angiography (OCTA). Methods: In the current prospective, cross-sectional, observational clinical study children and adolescents with T1D without DR were evaluated between December 2018 and May 2019. Retinal neurovascular structures in the macular and optic disc regions were examined in detail and quantitatively assessed using OCT and OCTA. Data from subjects with T1D were compared with data from healthy controls. Whether retinal neurovascular structural changes were significantly associated with puberty stage, diabetes duration, and HbA1c level was also investigated. Results: The T1D group included 110 eyes and the control group included 84 eyes. In the T1D group the mean inside disc vessel density (VD) was significantly lower than that of the control group (p < 0.001), as was the mean superior temporal disc VD (p < 0.043). Puberty stage was significantly associated with retinal thickness, parafoveal superficial capillary plexus VD, and peripapillary retinal nerve fiber layer thickness (p < 0.05). Diabetes duration and HbA1c level was significantly correlated with retinal layer thickness, foveal avascular zone diameter, and superficial and deep capillary plexus VDs. Conclusion: In children and adolescents with T1D without clinical signs of DR, the VD of the disc region is affected earlier than the macular region. In these patients, early neurovascular impairment can be detected non-invasively via OCT and OCTA. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to quantify retinal capillary density and foveal avascular zone (FAZ) area in healthy subjects according to their ethnicity, using optical coherence tomography angiography (OCTA). Methods: In this cross-sectional study, all eyes underwent swept-source OCTA (Triton, Topcon, Tokyo, Japan). Macular OCTA scans (3 × 3 mm) were obtained in healthy white Caucasian and black African subjects. The FAZ area and capillary density in both the superficial (SCP) and deep capillary plexuses (DCP) were automatically measured using a custom-made software combining vessel binarization and skeletonization. Results: Twelve eyes of 12 healthy Caucasians and 15 eyes of 15 healthy black Africans were included in the analysis. The mean FAZ area was significantly smaller, and the overall vessel density (VD) was higher in the SCP and DCP of Caucasians compared to black Africans. The mean FAZ area was 0.26 ± 0.008 mm2 in the SCP and 0.25 ± 0.05 mm2 in the DCP in Caucasians versus 0.33 ± 0.08 mm2 in the SCP (p = 0.01) and 0.37 ± 0.1 mm2 in the DCP (p = 0.03) in Africans. In the SCP and DCP, the mean VD was, respectively, 40.5 ± 0.8% and 47.1 ± 0.5% in Caucasians versus 34.3 ± 1% (p = 0.008) and 40.6 ± 0.9% in Africans (p < 0.001). Discussion/conclusion: In the SCP and DCP, VD is lower in black Africans compared to Caucasians. In OCTA studies on vascular diseases, ethnicity-matched measurements from healthy subjects should be used for comparisons. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the retinal microvascular density using optical coherence tomography angiography (OCTA) in patients with systemic lupus erythematosus (SLE) treated with hydroxychloroquine (HCQ). Methods: Nineteen eyes of 19 patients with SLE (study group) without HCQ retinopathy and 19 eyes of 19 healthy subjects (control group) were included in this study. The study group was divided into patients using HCQ for > 5 years (high-risk group) and < 5 years (low-risk group). The VD data of the 3 × 3 mm OCT angiogram of the superficial capillary plexus (SCP) and the choriocapillaris (VD-CC), the foveal avascular zone (FAZ) area and the central retinal thickness (CRT) were extracted and analyzed. Results: VD in the en face SCP was significantly reduced in the high-risk group and the low-risk group compared with that in the control group (p < 0.001, p = 0.001) and in the high-risk group compared with the low-risk group (p = 0.007). Correlation analysis between the cumulative dose of HCQ and the VD of the study group revealed a negative correlation, but no statistical significance (p = 0.074). However, a significant positive correlation was observed for the low-risk group (p = 0.035). In patients with SLE, VD-CC was lower (p = 0.042) and the FAZ area larger (p = 0.019). CRT showed no difference between the groups (p = 0.183). Conclusion: In this study, SLE patients showed a reduced VD in both groups. In patients treated with HCQ < 5 years, HCQ might have a protective effect on retinal microvasculature. Analysis of retinal microvascular density using OCTA could be useful in the diagnosis and monitoring of vascular alteration in patients with SLE. [ABSTRACT FROM AUTHOR]

Background: Rhegmatogenous retinal detachment associated with choroidal detachment (RRDCD) refers to the detachment of the ciliary body and choroid from the sclera along with retinal detachment. The recovery of visual function is often far worse after surgical treatment of RRDCD than following anatomical reduction for complicated reasons. Some scholars have suggested that oxidative stress may cause serious damage to cells when the detached retina becomes reduced to the choroid–retinal pigment epithelium complex and consequentially has an abnormal blood supply, which may limit the recovery of vision after surgery. Aims: To observe changes in the blood flow in the macula in patients with RRDCD who underwent pars plana vitrectomy (PPV) for retinal reattachment and silicone oil filling. Methods: This retrospective, cohort-controlled study included 35 patients with RRDCD who underwent PPV for the first time and whose retinas were successfully reattached from January 2017 to May 2018. Another 36 patients with rhegmatogenous retinal detachment (RRD) who underwent PPV for the first time and had their retina reattached as well as 40 normal eyes were assessed as controls. The best corrected visual acuity (BCVAs; logMAR) and intraocular pressure were recorded at 1 day, 1 week, 1 month, and 3 months after the operation was recorded. Optical coherence tomography angiography was used to measure the area of the foveal avascular zone. Results: At each time point after the operation, the area of the superficial plexus foveal avascular zone was not significantly different between the RRDCD and RRD groups. The area of the deep plexus foveal avascular zone (DFAZ) continued to enlarge after the operation in the RRDCD group but did not significantly change in the RRD group. A comparison of the two groups revealed that the DFAZ area was significantly larger in the RRDCD group than in the RRD group. The changes in DFAZ area in the RRDCD group were significantly different between 1 day to 1 month postoperatively (t = 0.054, P < 0.001), but there was no significant difference in the change from 1 to 3 months postoperatively (t = 0.014, P = 0.063). The correlation between BCVA at 3 months and DFAZ area one day after the operation in the RRDCD group was significant. Conclusion: Choroidal lesions in RRDCD patients may have an acute pathological effect on ischaemia of the deep retinal capillary network. The DFAZ area in RRDCD patients can be used to predict and evaluate postoperative visual acuity. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to compare the macular and peripapillary capillary vessel density (CVD) and foveal avascular zone (FAZ) in amblyopic eyes of adults with their fellow eyes and with eyes of healthy controls using optical coherence tomography-angiography (OCT-A). Methods: A total of 34 eyes of 17 patients with anisometropic amblyopia and 80 eyes of 40 age- and gender-matched healthy controls were included. CVD in superficial (SCP) and deep retinal capillary plexuses (DCP), peripapillary region, and FAZ were analyzed by OCT-A. Results: The median ages were 31 years (range 20–64) in patients with amblyopia and 34.5 years (range 24–65) in healthy controls (p = 0.242). The mean FAZ area measured was 0.329 ± 0.024 mm2 in amblyopic eyes, 0.332 ± 0.025 mm2 in fellow eyes, and 0.269 ± 0.015 mm2 in control eyes (p < 0.05). The amblyopic eye of participants showed a decrease in CVD of SCP and DCP (p < 0.001, for all). The inside optic disk CVD measurements were lower in the amblyopic eyes than in the fellow eyes (p = 0.001) and healthy subjects (p = 0.015). Conclusion: Significant differences in macular and peripapillary microvasculature were found in anisometropic amblyopic patients. The clinical significance of the results requires further investigation. [ABSTRACT FROM AUTHOR]

Purpose: Optical coherence tomography angiography (OCTA) was performed on patients with juvenile-onset type 1 diabetes (T1DM) but with no diabetic retinopathy to measure the foveal avascular zone (FAZ) area. Study Design: Retrospective single-facility study Methods: Twenty-nine patients (58 eyes) with juvenile-onset T1DM were studied. Images (3 mm x 3 mm cube centered on the fovea) were acquired using an OCTA device. Age at examination was 16.1 ± 8.7 years; onset age was 6.4 ± 3.5 years; duration of diabetes was 9.7 ± 8.3 years. Twenty-four age-matched healthy individuals were studied as controls. Results: FAZ area was significantly larger in T1DM patients than in controls (0.29 ± 0.09 vs. 0.25 ± 0.08 mm2, P = 0.0234). Parafoveal vessel density was not significantly different between patients and controls (50.43 ± 4.24 vs. 50.07 ± 4.64, P = 0.8842). By generalized linear model analysis, annual HbA1c (P = 0.0190), number of serious hypoglycemic attacks (P = 0.0210), and onset age (P = 0.0447) were identified as variables significantly associated with FAZ area. Age, gender, duration of disease, total cholesterol, high or low-density lipoprotein, triglycerides, and body mass index were not significantly associated with FAZ area. Conclusion: Patients with juvenile-onset T1DM and no diabetic retinopathy had increased FAZ, but no significant difference in parafoveal vessel density compared to healthy controls. Larger FAZ area was associated with higher annual HbA1c, more episodes of severe hypoglycemic attacks, and older onset age. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the foveal avascular zone (FAZ) in patients with diabetes and no retinopathy vs. controls using OCT angiography (OCT-A). Methods: Prospective, observational clinical study. Type I and II diabetics with no retinopathy and healthy control patients underwent OCT-A. The FAZ size and capillary density were calculated using Image J and Adobe Photoshop CS8. Statistical analysis was performed using one-way ANOVA with Tukey's multiple comparison test and the Pearson correlation test. Results: Fifty-two eyes of 28 diabetic patients and 28 eyes of 16 healthy controls were enrolled. Type I diabetes patients had a longer disease duration than type II (30.3 ± 10.3 vs. 12.3 ± 9.7 years). The mean superficial capillary plexus (SCP) of the FAZ area was 0.27 ± 0.1, 0.36 ± 0.14, and 0.27 ± 0.12 mm2, for the type I, type II, and controls (p = 0.0058) and was significantly larger in type II diabetics (p < 0.05). The mean DCP (deep capillary plexus) FAZ was significantly larger in type II diabetics vs. controls (0.67 ± 0.2 and 0.52 ± 0.16 mm2 respectively) (p < 0.05). Both type I and type II SCP capillary density were significantly lower than the controls (p < 0.05, p < 0.005), and DCP capillary density was significantly lower in type II vs. controls (p < 0.005). Conclusions: Type I patients showed fewer changes in the FAZ than the type II group, although their duration of diabetes was longer. Larger studies are needed to better analyze the differences between type I and type II diabetics. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the reliability of the foveal avascular zone (FAZ) metrics automatically measured using Cirrus optical coherence tomography angiography (OCTA) embedded algorithm compared to human manual measurement. Methods: Thirty-five eyes of 35 healthy subjects were enrolled and scanned four times continuously on Zeiss Cirrus HD-OCT 5000. The FAZ metrics (area, circularity and perimeter) of the superficial capillary plexus were measured automatically using the embedded tool and manually measured by the two independent observers using ImageJ. The repeatability of the four scans within all methods of measurements was calculated. The agreement of the manual vs automated measurement was also analyzed. Results: The repeatability of the automated algorithm was only poor to moderate (intraclass correlation coefficients [ICCs] for the area, perimeter and circularity were 0.600, 0.405 and 0.221, respectively) while the repeatability of the manually measured FAZ area and perimeter was good [([ICCs] ranged from 0.845 to 0.877) except the circularity (ICC = 0.538 to 0.608)]. The ranges of 95% limits of agreement between the manual measurements by the two observers were only 20% to 31% of those of automated–manual agreement. The Cirrus inbuilt algorithm obviously outlined the border of FAZ wrongly in 22.9% cases. Conclusion: Caution should be taken when using the automated measurement results of FAZ metrics in Cirrus OCTA, because of the low repeatability and poor agreement compared with the manual measurement. [ABSTRACT FROM AUTHOR]

Purpose: To compare optical coherence tomography angiography (OCT-A) parameters between type 1 and type 2 diabetic patients with diabetic retinopathy (DR). Methods: A total of 70 patients with type 1 diabetes and 70 with type 2 diabetes were retrospectively analyzed. DR was graded as no DR, mild nonproliferative DR (NPDR), moderate NPDR, severe NPDR, and proliferative DR (PDR). Using OCT-A, the foveal avascular zone (FAZ) area (mm2) and vascular density (VD) (%) were calculated in the superficial capillary plexus (SCP) and deep capillary plexus (DCP). Results: In both type 1 and 2 diabetes patients, the FAZ area (mm2) in both capillary plexuses (CP) increased with DR progression, whereas the VD (%) progressively decreased. The changes in the FAZ area and the VD were significantly greater in the DCP than in the SCP in both types of diabetes patients(p < 0.001). In the analysis of decreasing slope of the VD in the DCP, attenuation was not significant until severe NPDR stage but then abruptly decreased when it progressed to PDR stage in type 1 diabetes. In type 2 diabetes, the DCP VD decreased gradually as DR stage progressed. Conclusions: As DR progression, the increasing in FAZ area and the decreasing in VD are more severe in the DCP than in the SCP in both types of diabetes. In type 1 diabetes eyes, they were remained in relatively healthy until it gets to the advanced stage of DR, while the gradual deterioration of FAZ area and VD was found from the early stage to the advanced stage of DR in type 2 diabetes. [ABSTRACT FROM AUTHOR]

Purpose: To measure the vascular density (VD) and foveal avascular zone (FAZ) area in patients with Behçet's disease (BD) obtained by optical coherence tomography angiography (OCTA). Methods: VD and FAZ area in the deep and superficial retinal vascular networks were measured in all eyes. Results: Thirty BD and 31 control subjects were included in the study. The mean overall VD measured in the entire scan was lower in BD compared with control group in both the superficial (49.52 ± 6.54 vs 53.57 ± 2.87%, respectively; p = 0.003) and deep (53.44 ± 7.44 vs 58.41 ± 3.01%, respectively; p = 0.002) areas. The FAZ in the BD group was significantly increased at the level of the superficial (0.52 ± 0.67 vs 0.28 ± 0.1 mm2, respectively; p = 0.05) and deep (0.91 ± 1.25 vs 0.39 ± 0.14 mm2, respectively; p = 0.024) areas compared with those of the control group. The deep and the superficial FAZ areas were positively correlated with disease duration and negatively with VA. Conclusion: In the patients with BD, OCTA showed decreased VD in both the superficial and deep retinal vascular networks. Besides, the VA was correlated with the VD and FAZ. [ABSTRACT FROM AUTHOR]

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.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.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).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.Clinical Trials.gov Identifier: ChiCTR2100046590Methods: 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.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.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).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.Clinical Trials.gov Identifier: ChiCTR2100046590Results: 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.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.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).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.Clinical Trials.gov Identifier: ChiCTR2100046590Conclusions: 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.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.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).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.Clinical Trials.gov Identifier: ChiCTR2100046590Trial registration: 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.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.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).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.Clinical Trials.gov Identifier: ChiCTR2100046590 [ABSTRACT FROM AUTHOR]

Copyright of Der Ophthalmologe 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.)

Copyright of Der Ophthalmologe 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.)

Purpose: Evaluation of foveal avascular zone (FAZ) in children with diabetes (DM) using OCTA. Methods: We examined 112 diabetic children without DR aged 6–18 years and 30 age-matched controls using Topcon OCT Angiography and measured FAZ in superficial (SCP) and deep capillary plexus (DCP). The study group was divided into three subgroups depending on DM duration group 1: < 5 years (n = 40), group 2: 5–10 years (n = 42), group 3: > 10 years (n = 30). Results: The mean DCP FAZ increased with DM duration from 502.2 μm2 (SD 137.8) in group 1 to 523.9 μm2 (SD 159.2) in group 2 and 539.7 μm2 (SD 189.1) in group 3. Control group differed significantly from group 1 (p = 0.0120), group 2 (p = 0.0019) and group 3 (p = 0.0011). The mean DCP to SCP FAZ surface ratio was 1.88 (SD 0.68) in the study vs 1.58 (SD 0.48) in the control group (p = 0.0232). The DCP and SCP FAZ surface difference was 217.6 μm2 (SD 100.8 μm2) in diabetics vs. 124.2 μm2 (SD 72.8 μm2) in controls (p < 0.0001). In the control group, it was significantly smaller than in group 1 (p < 0.006), group 2 (p < 0.0001) and group 3 (p < 0.0001). Conclusions: Changes can be detected in FAZ of diabetic children before DR development which can be vital for screening. [ABSTRACT FROM AUTHOR]

Purpose: Persistent metamorphopsia, particularly aniseikonia, is a troublesome problem which may occur after epiretinal membrane (ERM) surgery. To clarify if the preoperative foveal avascular zone (FAZ) morphology can be used as a predictor of postoperative residual aniseikonia, the morphological changes in the FAZ and the degree of aniseikonia between before and 12 months after vitrectomy for epiretinal membrane (ERM) were measured and analyzed.Methods: Thirty patients, each with a unilateral idiopathic ERM, who underwent treatment between September 2016 and March 2017 were enrolled for this prospective case series study. Best-corrected visual acuity (BCVA), the degree of aniseikonia, central foveal thickness (CFT), FAZ area (FAZa), perimeter (FAZp), and circularity in ERM eyes were examined before and 1, 3, 6 and 12 months after surgery. The fellow eye without an ERM was also examined and used as the control. The interocular ratios of the CFT, FAZa, and FAZp in ERM eyes with those in control eyes were also calculated. Multiple regression analysis was performed on preoperative parameters that were found to be significantly correlated with the 12-month aniseikonia in univariate analyses.Results: The BCVA in the ERM eyes was significantly improved at 1 month after surgery (P < .0001) The degree of aniseikonia was significantly reduced only after 12 months (P = .004). The CFT had decreased significantly by 3 months after the surgery and continued decreasing thereafter (P < .0001). Both FAZa and FAZp were significantly smaller in the ERM eyes than in the control eyes throughout the study period (P < .0001 and P < .0001, respectively), with no change in either parameter over the study period. Correlation analyses revealed that the degree of aniseikonia was significantly correlated with pre- and postoperative CFT, CFT ratio, FAZa, FAZa ratio, FAZp, and FAZp ratio. Within preoperative OCT parameters, FAZa ratio remained significant after multiple regression analysis was performed (P < .0001).Conclusions: Aniseikonia changed little over the long term following ERM surgery. Preoperative FAZ area ratio was identified as a significant predictor of postoperative aniseikonia. [ABSTRACT FROM AUTHOR]

Purpose: To assess foveal microvascular structure and the correlation between foveal retinal thickness and best corrected visual acuity (BCVA) in children with retinopathy of prematurity (ROP).Methods: This is a retrospective case-control study. A total 42 eyes in 23 patients with history of anti-vascular endothelial factor (VEGF) agent treatment and 51 eyes of 27 healthy age-matched subjects as the control group were analyzed. Foveal avascular zone (FAZ) and foveal vessel density (VD) were measured by optical coherence tomography angiography (OCT-A). Foveal thickness was measured by cross-sectional OCT. Correlations between FAZ area, foveal VD, foveal thickness, BCVA, gestational age (GA), and birth body weight (BBW) were performed.Results: ROP children had a significantly smaller FAZ area and higher foveal VD, and the foveal thickness was significantly higher as compared to controls (all P < 0.0001). We noted a significant negative correlation between FAZ area and foveal thickness. In addition, a significant positive correlation between foveal VD and foveal thickness was identified. With regard to prematurity status, gestational age and birth body weight were both significantly correlated with FAZ area, foveal VD, and fovea inner retinal thickness. Multivariable analysis showed that thicker inner retinal thickness and higher superficial vascular density were associated with suboptimal visual acuity.Conclusion: By using OCT-A, we identified significant foveal microvascular anomalies in ROP children. The correlation between the microvascular anomalies, central foveal thickness, and suboptimal visual acuity was also noted. Because of the retrospective nature, more studies are necessary to further establish the relationship. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the relationship between the foveal avascular zone (FAZ) and the inner nuclear layer (INL)-free zone in the center of the fovea in order to provide an improved approach to evaluation of the FAZ area with optical coherence tomography angiography (OCTA).Methods: Thirty-six healthy individuals (36 eyes) and 15 age-matched patients (15 eyes) with nonproliferative diabetic retinopathy (nPDR) were included in this study. The FAZ, as well as INL-free zone, was measured on OCTA images. The FAZ area, INL-free zone area, and the ratio of the INL-free zone area to the FAZ area were compared between healthy subjects and nPDR patients.Results: The mean FAZ area in healthy subjects and nPDR patients was 0.33 ± 0.1 mm2 and 0.41 ± 0.19 mm2 (p < 0.05), respectively. The mean INL-free zone area in healthy subjects and nPDR patients was 0.33 ± 0.07 mm2 and 0.25 ± 0.09 mm2 (p > 0.05), respectively. The INL-free zone area to the FAZ area ratio in healthy subjects and nPDR patients was 1.08 ± 0.25 and 0.56 ± 0.18 (p < 0.001), respectively. Receiver operating characteristic analysis showed that the INL-free zone area to the FAZ area ratio had a higher area under curve (0.94; 80.0% sensitivity and 97.2% specificity) compared to the FAZ area (0.61; 40.0% sensitivity and 94.4% specificity) for differentiating nPDR from healthy eyes.Conclusion: This study showed that analysis of the FAZ based on the ratio of the INL-free zone area to the FAZ area has better accuracy compared to the conventional FAZ area measurement in differentiating eyes with mild to moderate nPDR without any structural abnormalities in the fovea from healthy eyes. [ABSTRACT FROM AUTHOR]

Background: Pars plana vitrectomy is the standard treatment for several vitreoretinal diseases. Continuous improvements in ophthalmic surgical techniques have led to excellent postoperative recovery of the anatomic structure of the fundus. However, postoperative visual outcomes are not always satisfactory.A literature search of articles published before 31 December 2022 was conducted on PubMed using the following keywords: “diabetic retinopathy,” “rhegmatogenous retinal detachment,” “idiopathic epiretinal membrane,” “idiopathic macular hole,” “vitrectomy,” “optical coherence tomography,” “optical coherence tomography angiography,” “microstructure,” “microstructural,” “hemodynamic,” “hemodynamics,” and “microcirculation.” Additional studies were identified by hand-searching references for relevant studies. Articles were screened for language, repetition, and relevance to the direction of study. Studies with a sample size ≥ 7 and the final follow-up time ≥ 4 weeks after vitrectomy were included in this review. Only articles published in English were included. Articles not related to our topic were excluded. Reviews and single case reports were excluded. We structured this review by disease category. The thickness of the retina and choroid, the area of the foveal avascular zone, the vessel density of the retinal and choroidal capillary plexus, and the potential association of related parameters with postoperative visual outcomes are the main outcome measures of studies included in this review.A total of 48 studies were included in this review. There were contradictory results regarding the association between postoperative microcirculatory parameters and visual acuity in patients with diabetic macular edema, with some studies concluding that improvement in perimacular microcirculation may be an important factor that affects visual acuity, and others concluded that postoperative improvement in visual acuity was not related to changes in macular blood flow. The results of studies on the relationship between postoperative microstructural and microcirculatory parameters and visual acuity in rhegmatogenous retinal detachment, idiopathic epiretinal membrane, and idiopathic macular hole eyes have been inconsistent. In gas tamponade macula-off rhegmatogenous retinal detachment eyes, postoperative best-corrected visual acuity has been reported to correlate positively with vessel density of deep capillary plexus and negatively with foveal avascular zone area of superficial capillary plexus and deep capillary plexus. In silicone oil tamponade macula-off rhegmatogenous retinal detachment eyes, best-corrected visual acuity has been reported to be positively correlated with the retinal thickness of the parafoveal 3 mm temporal quadrant and positively correlated with the vessel density of the superficial capillary plexus in the foveal, parafoveal, and perifoveal area. In addition, best-corrected visual acuity was worse and associated with reduced thickness of the inner retina, ganglion cell layer, outer plexiform layer, and outer nuclear layer in silicone oil tamponade rhegmatogenous retinal detachment eyes compared to gas tamponade. Postoperative best-corrected visual acuity in idiopathic epiretinal membrane eyes was positively correlated with the foveal avascular zone area but negatively correlated with full retinal thickness and inner retinal thickness in the foveal and parafoveal areas. Improvement in postoperative best-corrected visual acuity in idiopathic macular hole eyes was associated with reduced inner retinal thickness and reduced foveal avascular zone area.Microstructural and hemodynamic changes are involved in the recovery process after PPV for different vitreoretinal diseases. The thickness of each retinal layer in different regions of the macula, foveal avascular zone area, and vessel density of different retinal capillary plexuses in different macular regions may be potential prognostic factors for postoperative visual recovery. However, the results of the existing literature are inconsistent and require further study.Methods: Pars plana vitrectomy is the standard treatment for several vitreoretinal diseases. Continuous improvements in ophthalmic surgical techniques have led to excellent postoperative recovery of the anatomic structure of the fundus. However, postoperative visual outcomes are not always satisfactory.A literature search of articles published before 31 December 2022 was conducted on PubMed using the following keywords: “diabetic retinopathy,” “rhegmatogenous retinal detachment,” “idiopathic epiretinal membrane,” “idiopathic macular hole,” “vitrectomy,” “optical coherence tomography,” “optical coherence tomography angiography,” “microstructure,” “microstructural,” “hemodynamic,” “hemodynamics,” and “microcirculation.” Additional studies were identified by hand-searching references for relevant studies. Articles were screened for language, repetition, and relevance to the direction of study. Studies with a sample size ≥ 7 and the final follow-up time ≥ 4 weeks after vitrectomy were included in this review. Only articles published in English were included. Articles not related to our topic were excluded. Reviews and single case reports were excluded. We structured this review by disease category. The thickness of the retina and choroid, the area of the foveal avascular zone, the vessel density of the retinal and choroidal capillary plexus, and the potential association of related parameters with postoperative visual outcomes are the main outcome measures of studies included in this review.A total of 48 studies were included in this review. There were contradictory results regarding the association between postoperative microcirculatory parameters and visual acuity in patients with diabetic macular edema, with some studies concluding that improvement in perimacular microcirculation may be an important factor that affects visual acuity, and others concluded that postoperative improvement in visual acuity was not related to changes in macular blood flow. The results of studies on the relationship between postoperative microstructural and microcirculatory parameters and visual acuity in rhegmatogenous retinal detachment, idiopathic epiretinal membrane, and idiopathic macular hole eyes have been inconsistent. In gas tamponade macula-off rhegmatogenous retinal detachment eyes, postoperative best-corrected visual acuity has been reported to correlate positively with vessel density of deep capillary plexus and negatively with foveal avascular zone area of superficial capillary plexus and deep capillary plexus. In silicone oil tamponade macula-off rhegmatogenous retinal detachment eyes, best-corrected visual acuity has been reported to be positively correlated with the retinal thickness of the parafoveal 3 mm temporal quadrant and positively correlated with the vessel density of the superficial capillary plexus in the foveal, parafoveal, and perifoveal area. In addition, best-corrected visual acuity was worse and associated with reduced thickness of the inner retina, ganglion cell layer, outer plexiform layer, and outer nuclear layer in silicone oil tamponade rhegmatogenous retinal detachment eyes compared to gas tamponade. Postoperative best-corrected visual acuity in idiopathic epiretinal membrane eyes was positively correlated with the foveal avascular zone area but negatively correlated with full retinal thickness and inner retinal thickness in the foveal and parafoveal areas. Improvement in postoperative best-corrected visual acuity in idiopathic macular hole eyes was associated with reduced inner retinal thickness and reduced foveal avascular zone area.Microstructural and hemodynamic changes are involved in the recovery process after PPV for different vitreoretinal diseases. The thickness of each retinal layer in different regions of the macula, foveal avascular zone area, and vessel density of different retinal capillary plexuses in different macular regions may be potential prognostic factors for postoperative visual recovery. However, the results of the existing literature are inconsistent and require further study.Results: Pars plana vitrectomy is the standard treatment for several vitreoretinal diseases. Continuous improvements in ophthalmic surgical techniques have led to excellent postoperative recovery of the anatomic structure of the fundus. However, postoperative visual outcomes are not always satisfactory.A literature search of articles published before 31 December 2022 was conducted on PubMed using the following keywords: “diabetic retinopathy,” “rhegmatogenous retinal detachment,” “idiopathic epiretinal membrane,” “idiopathic macular hole,” “vitrectomy,” “optical coherence tomography,” “optical coherence tomography angiography,” “microstructure,” “microstructural,” “hemodynamic,” “hemodynamics,” and “microcirculation.” Additional studies were identified by hand-searching references for relevant studies. Articles were screened for language, repetition, and relevance to the direction of study. Studies with a sample size ≥ 7 and the final follow-up time ≥ 4 weeks after vitrectomy were included in this review. Only articles published in English were included. Articles not related to our topic were excluded. Reviews and single case reports were excluded. We structured this review by disease category. The thickness of the retina and choroid, the area of the foveal avascular zone, the vessel density of the retinal and choroidal capillary plexus, and the potential association of related parameters with postoperative visual outcomes are the main outcome measures of studies included in this review.A total of 48 studies were included in this review. There were contradictory results regarding the association between postoperative microcirculatory parameters and visual acuity in patients with diabetic macular edema, with some studies concluding that improvement in perimacular microcirculation may be an important factor that affects visual acuity, and others concluded that postoperative improvement in visual acuity was not related to changes in macular blood flow. The results of studies on the relationship between postoperative microstructural and microcirculatory parameters and visual acuity in rhegmatogenous retinal detachment, idiopathic epiretinal membrane, and idiopathic macular hole eyes have been inconsistent. In gas tamponade macula-off rhegmatogenous retinal detachment eyes, postoperative best-corrected visual acuity has been reported to correlate positively with vessel density of deep capillary plexus and negatively with foveal avascular zone area of superficial capillary plexus and deep capillary plexus. In silicone oil tamponade macula-off rhegmatogenous retinal detachment eyes, best-corrected visual acuity has been reported to be positively correlated with the retinal thickness of the parafoveal 3 mm temporal quadrant and positively correlated with the vessel density of the superficial capillary plexus in the foveal, parafoveal, and perifoveal area. In addition, best-corrected visual acuity was worse and associated with reduced thickness of the inner retina, ganglion cell layer, outer plexiform layer, and outer nuclear layer in silicone oil tamponade rhegmatogenous retinal detachment eyes compared to gas tamponade. Postoperative best-corrected visual acuity in idiopathic epiretinal membrane eyes was positively correlated with the foveal avascular zone area but negatively correlated with full retinal thickness and inner retinal thickness in the foveal and parafoveal areas. Improvement in postoperative best-corrected visual acuity in idiopathic macular hole eyes was associated with reduced inner retinal thickness and reduced foveal avascular zone area.Microstructural and hemodynamic changes are involved in the recovery process after PPV for different vitreoretinal diseases. The thickness of each retinal layer in different regions of the macula, foveal avascular zone area, and vessel density of different retinal capillary plexuses in different macular regions may be potential prognostic factors for postoperative visual recovery. However, the results of the existing literature are inconsistent and require further study.Conclusions: Pars plana vitrectomy is the standard treatment for several vitreoretinal diseases. Continuous improvements in ophthalmic surgical techniques have led to excellent postoperative recovery of the anatomic structure of the fundus. However, postoperative visual outcomes are not always satisfactory.A literature search of articles published before 31 December 2022 was conducted on PubMed using the following keywords: “diabetic retinopathy,” “rhegmatogenous retinal detachment,” “idiopathic epiretinal membrane,” “idiopathic macular hole,” “vitrectomy,” “optical coherence tomography,” “optical coherence tomography angiography,” “microstructure,” “microstructural,” “hemodynamic,” “hemodynamics,” and “microcirculation.” Additional studies were identified by hand-searching references for relevant studies. Articles were screened for language, repetition, and relevance to the direction of study. Studies with a sample size ≥ 7 and the final follow-up time ≥ 4 weeks after vitrectomy were included in this review. Only articles published in English were included. Articles not related to our topic were excluded. Reviews and single case reports were excluded. We structured this review by disease category. The thickness of the retina and choroid, the area of the foveal avascular zone, the vessel density of the retinal and choroidal capillary plexus, and the potential association of related parameters with postoperative visual outcomes are the main outcome measures of studies included in this review.A total of 48 studies were included in this review. There were contradictory results regarding the association between postoperative microcirculatory parameters and visual acuity in patients with diabetic macular edema, with some studies concluding that improvement in perimacular microcirculation may be an important factor that affects visual acuity, and others concluded that postoperative improvement in visual acuity was not related to changes in macular blood flow. The results of studies on the relationship between postoperative microstructural and microcirculatory parameters and visual acuity in rhegmatogenous retinal detachment, idiopathic epiretinal membrane, and idiopathic macular hole eyes have been inconsistent. In gas tamponade macula-off rhegmatogenous retinal detachment eyes, postoperative best-corrected visual acuity has been reported to correlate positively with vessel density of deep capillary plexus and negatively with foveal avascular zone area of superficial capillary plexus and deep capillary plexus. In silicone oil tamponade macula-off rhegmatogenous retinal detachment eyes, best-corrected visual acuity has been reported to be positively correlated with the retinal thickness of the parafoveal 3 mm temporal quadrant and positively correlated with the vessel density of the superficial capillary plexus in the foveal, parafoveal, and perifoveal area. In addition, best-corrected visual acuity was worse and associated with reduced thickness of the inner retina, ganglion cell layer, outer plexiform layer, and outer nuclear layer in silicone oil tamponade rhegmatogenous retinal detachment eyes compared to gas tamponade. Postoperative best-corrected visual acuity in idiopathic epiretinal membrane eyes was positively correlated with the foveal avascular zone area but negatively correlated with full retinal thickness and inner retinal thickness in the foveal and parafoveal areas. Improvement in postoperative best-corrected visual acuity in idiopathic macular hole eyes was associated with reduced inner retinal thickness and reduced foveal avascular zone area.Microstructural and hemodynamic changes are involved in the recovery process after PPV for different vitreoretinal diseases. The thickness of each retinal layer in different regions of the macula, foveal avascular zone area, and vessel density of different retinal capillary plexuses in different macular regions may be potential prognostic factors for postoperative visual recovery. However, the results of the existing literature are inconsistent and require further study. [ABSTRACT FROM AUTHOR]

Copyright of Der Ophthalmologe 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.)

Purpose: To compare the superficial (FAZ-S) and deep foveal avascular zones (FAZ-D) of non-infectious anterior and posterior uveitis to healthy controls, using optical coherence tomography angiography (OCTA).Methods: OCTA was performed on 74 eyes: 34 eyes with non-infectious posterior uveitis (with (post+CME) and without macular edema (post−CME)), 11 eyes with non-infectious anterior uveitis (with (ant+CME) and without macular edema (ant−CME)), and the control group which included 29 healthy eyes.Results: Eyes suffering from non-infectious posterior uveitis presented with significantly larger FAZ-D when compared to healthy controls, both in the presence or in the absence of macular edema (p < 0.001). In the presence of macular edema, eyes presenting with anterior uveitis (ant+CME) also showed significantly larger FAZ-S (p = 0.03) and FAZ-D (p < 0.001), when compared to healthy controls. In the absence of macular edema, eyes with anterior uveitis cannot be distinguished from controls (p > 0.6).Conclusion: The deep retinal foveal avascular zone seems to be enlarged in eyes presenting with non-infectious posterior uveitis, both in the presence or absence of macular edema. [ABSTRACT FROM AUTHOR]

Purpose: To examine the vascular density in different retinal layers and in the choriocapillaris in eyes with retinal vein occlusions (RVO).Methods: Applying optical coherence tomography angiography (OCTA), we examined patients with unilateral RVOs and normal individuals of a control group.Results: The study group included 48 patients with unilateral RVO and the control group 17 normal individuals. Eyes affected by RVO as compared to the contralateral unaffected eyes (all P < 0.001), and the contralateral unaffected eyes as compared to the eyes of the control group (P < 0.05), showed a lower vessel density in the superficial and deep retinal layers in all regions except for the foveal region. Choriocapillaris density was lower (P < 0.001), foveal retinal thickness and subfoveal choroidal thickness (P < 0.001) were thicker, and the foveal avascular zone was larger (P = 0.003) in the RVO eyes than in the contralateral eyes. For 29 eyes undergoing OCTA and fluorescein angiography, two examiners independently rated the retinas to be ischemic in fluorescein angiography in 14 eyes and in OCTA in 9 of these 14 eyes.Conclusions: Upon OCTA, unaffected eyes of patients with unilateral RVOs showed vascular abnormalities in the superficial and deep retinal layers when compared to those of healthy individuals. [ABSTRACT FROM AUTHOR]