Foveal Vessel Density Research Articles

Changes of retinal vessel density in low to moderate myopic eyes with orthokeratology evaluated by optical coherence tomography angiography.

To explore the effect of orthokeratology (OK) fitting on retinal vessel density in low to moderate myopia adolescents by using optical coherence tomography angiography. Children aged 10 to 14y with a cycloplegic spherical equivalent refraction of -0.50 diopter (D) to -5.00 D and astigmatism with more than -1.50 D were recruited. The enrolled adolescents were divided into OK group and spectacle group. During regular follow-up, adolescents were measured respectively at pre-wear, 1, 3, and 6mo after treatment. The follow-up included uncorrected distance visual acuity (UDVA), axial length (AL), superficial capillary plexus density (SCPD), deep capillary plexus density (DCPD), central retinal thickness (CRT), foveal avascular zone area (FAZ-A), foveal avascular zone perimeter (FAZ-P) and foveal vessel density in a 300-µm-wide region around foveal avascular zone (FD-300). The collected data were analyzed using statistical methods. By one month, SCPD significantly increased in the fovea and superior retina, and DCPD significantly increased inferiorly in OK group compared to spectacle group (P<0.05). By three months, there were significant increases in SCPD in the fovea and inferior retina, and DCPD in the parafovea, superior, and inferior retina in OK group (P<0.05), while the increase in SCPD and DCPD in the fovea were observed by six months (P<0.05). The FD-300 significantly increased at every follow-up in OK group compared to spectacle group (P<0.05). No significant differences in the CRT, FAZ-A and FAZ-P and FD-300 were observed between two groups (P>0.05). OK group showed a significant improvement in UDVA after wearing OK, compared to spectacle group (P<0.01), while the AL did not show a significant difference between two groups (P>0.05). Short-term OK worn can increase local retinal vessel density in adolescents with low-to-moderate myopia.

Epiretinal membrane related vascular changes in diabetic eyes evaluated with optical coherence tomography angiography.

To evaluate the retinochoroidal microvascular circulation and anatomical structure of diabetic and non-diabetic patients with epiretinal membrane (ERM) with the help of optical coherence tomography angiography (OCT-A) and compare them with healthy control subjects. In this prospective, cross-sectional study, a total of 165 eyes were evaluated, including 50 eyes of patients with diabetic ERM, 54 eyes of idiopathic ERM (iERM) patients, and 61 eyes of healthy controls. Macula and disc angiography was performed by OCT-A. Macular vessel density (VD) ratio was evaluated by dividing the VD of the foveal region by the VD of the parafoveal region. Statistical calculations were evaluated at the 95% confidence interval. Macula superficial VD values of ERM cases were lower than that in the control group, while foveal VD was higher in ERM cases. Macula deep VD values of ERM cases were lower in all quadrants, except the fovea. The width of the foveal avascular zone (FAZ) area was significantly lower in the ERM groups, and the FAZ width was lowest in iERM group. Macula superficial VD ratio was significantly higher in the ERM groups, but there was no significant difference between ERM groups. Macula deep VD ratio was significantly higher in the iERM group than in the control group. Diabetic and idiopathic ERMs differ in their mechanism of formation and clinical presentation, as well as their effect on retinal vascular structures. If the relationship of increase of retinal thickness with vascular integrity can be demonstrated with OCT-A, then, OCT-A can be used as a guide for ERM prognosis.

Optical coherence tomography angiography metrics in diabetes: Focusing on diabetic retinopathy and carotid atherosclerosis

BackgroundTo explore the value of Optical Coherence Tomography Angiography (OCTA) metrics in the early diagnosis of vascular complications in diabetes. MethodsAll participants underwent OCTA with a swept-source OCT device. Automated measurements of the foveal avascular zone (FAZ) area, vessel density (VD), and blood flow density (BFD) of both 3 × 3 and 6 × 6 windows were then obtained after a quality check. ResultsDiagnostic models based on multiple risk factors were developed separately for diabetic retinopathy and carotid atherosclerosis using random forest and multivariate logistic regression methods. The addition of specific OCTA metrics improved the diagnostic prediction of DR compared with the models of risk factors alone (Inner Retinal Blood Flow Density in 3 × 3 window, IRBFD; Brier score 0.124 vs. 0.149; AUC, 0.887 vs. 0.836) (Central Retinal Blood Flow Density in 3 × 3 window, CRBFD; Brier score 0.142 vs. 0.149; AUC, 0.851 vs. 0.836). Adding diabetic peripheral vascular disease (DPVD) indicator improved the prediction of carotid atherosclerosis (Brier score, 0.180 vs. 0.192; AUC, 0.802 vs. 0.781. The FAZ in the 3 × 3 window also achieved this effect when targeting only T2DM patients (AUC, 0.797 vs. 0.766; Brier score, 0.183 vs. 0.195). ConclusionsFocusing on IRBFD and CRBFD in the 3 × 3 window of OCTA allows for a more sensitive prediction of the occurrence of DR in diabetic patients. Meanwhile, the quantitative microvascular information provided by OCTA and the occurrence of DPVD may be crucial for diagnosing carotid atherosclerosis. For T2DM patients, we also propose the possibility of FAZ in the 3 × 3 window as a potential diagnostic indicator.

Short-term effects of occlusion therapy and optical correction on microvasculature in monocular amblyopia: a retrospective case–control study

This retrospective longitudinal case–control study investigated the short-term effects of patch occlusion treatment compared with optical correction on the microvasculature in monocular amblyopia. We included patients with monocular amblyopia treated for 2–12 months; they were classified into two groups according to the treatment regimen: patch occlusion or optical correction. Children aged < 12 years who presented to our clinic for examination without amblyopia diagnosis were enrolled as the control group. Changes in retinal and choroid microvasculature according to treatment were examined, and the correlation between changes in microvasculature and improvement in best-corrected visual acuity (BCVA) was evaluated. There were 57, 35, and 41 patients in the patch occlusion, optical correction, and control groups, respectively (mean age, 6.4 ± 2.0 years). Both amblyopic groups showed changes in the foveal and parafoveal deep capillary plexus vessel density (DCPD), choroidal thickness, and choroidal vascularity index (CVI) following short-term treatment (mean, 4.5 months). In the patch occlusion group, BCVA improved as the foveal DCPD increased (P = 0.013) and the CVI decreased (P = 0.037). In the optical correction group, BCVA improved as the foveal and parafoveal DCPD increased (P = 0.009). Increased foveal DCPD following amblyopia treatment and decreased CVI by patch occlusion were associated with improved BCVA.

Epiretinal Membrane of Combined Hamartoma of Retina and Retinal Pigment Epithelium Versus Idiopathic Epiretinal Membrane

Purpose: To evaluate the postoperative changes in macular vessel density and the multifocal electroretinogram (mfERG) in the epiretinal membrane (ERM) of a combined hamartoma of the retina and retinal pigment epithelium (CHRRPE). And we compared these results with those of idiopathic ERM.Method: We retrospectively reviewed the records of 15 patients (15 eyes) with an epiretinal membrane of a CHRRPE, and 21 patients (21 eyes) with idiopathic ERM who were treated with pars plana vitrectomy and removal of the ERM. The best corrected visual acuity, central macula thickness, foveal and perifoveal vessel density, foveal avascular zone (FAZ), and mfERG rings 1 and 2 P1 amplitudes were analyzed before and 6 months after ERM removal.Results: The average macular vessel density in the CHRRPE with ERM was reduced (p = 0.047) compared to an idiopathic epiretinal membrane, but the central foveal vessel density was significantly increased (p = 0.003). In CHRRPE, the preoperative FAZ was significantly reduced, and while it increased significantly 6 months postoperatively. After removing the ERM, the P1 amplitude increased significantly on mfERG, but there was no significant difference compared to the idiopathic ERM.Conclusions: The macular mean superficial capillary plexus (SCP) vascular density was reduced in CHRRPE and the foveal SCP vascular density and FAZ were increased. Considering the increased size of the FAZ area after surgery, physical removal of the ERM affected the structural recovery of the fovea, but resulted in no significant improvement of the macular superficial microvascular system.

Optical coherence tomography angiography aspects of the retinal and optic disc microvascular morphology in erythemato-telangectatic rosacea

BackgroundTo investigate retinal and optic disc (OD) microvascular morphological changes in erythemato-telangiectatic rosacea (ETR) patients using optical coherence tomography angiography (OCTA), and compare the findings to age- and gender-matched healthy individuals. MethodsThis study included newly diagnosed 31 ETR patients (31 right eyes, group 1) who were clinically diagnosed by two experienced dermatologists. A control group had 32 healthy individuals (32 right eyes, group 2). Demographic data, including age and gender were collected, followed by a thorough ophthalmologic exam. A 6 × 6 mm macular OCTA analysis of superficial and deep capillary plexus (SCP and DCP) vessel densities (VDs), as well as foveal avascular zone (FAZ) area, FAZ perimeter (PERIM), foveal VDs 300 µm area around FAZ (FD-300), and flow areas in the outer retinal and choriocapillaris, was then performed. ResultsMean age in groups 1 and 2 was 43.70 ± 13.02 and 43.62 ± 12.30 years, respectively (p=0.979). Male-to-female ratio in group 1 was 4:27 and 4:28 in group 2. Capillary flow analysis revealed slightly higher values in group 1 than in group 2, with the former having a significantly higher select area in the outer retinal layer (p=0.001) and flow area in the choriocapillaris (p=0.002). Despite slightly higher values in group 1, there were no significant differences in SCP and DCP VDs (p > 0.05), FAZ area (p=0.471), PERIM (p=0.778), or FD-300 (p=0.527). ConclusionsETR appears to be associated with posterior segment changes, especially retinal microvascular morphology, even in asymptomatic ocular conditions. Given the disease's high rate of misdiagnosis, understanding rosacea-induced ocular manifestations is critical for ophthalmologists

Longitudinal changes of parafoveal vessel density in diabetic patients without clinical retinopathy using optical coherence tomography angiography

Purpose The purpose of this study was to identify the rate of parafoveal vessel density (VD) changes associated with the progression from non-diabetic retinopathy (NDR) to early stages of DR over a year. Methods This longitudinal cohort study enrolled diabetic patients from the Guangzhou community in China. The patients with NDR at baseline were included and underwent comprehensive examinations at baseline and after 1 year. A commercial OCTA device (Triton Plus, Topcon, Tokyo, Japan) was employed to quantify the foveal VD in the superficial and deep capillary plexuses. The rates of change in parafoveal VD over time in the incident DR and NDR groups were compared after a year. Results A total of 448 NDR patients were included in the study. Among them, 382 (83.2%) were stable and 66 (14.4%) developed incident DR during the 1-year follow-up. The average parafoveal VD in the superficial capillary plexus (SCP) reduced significantly more quickly in the incident DR group than in the NDR group (-1.95 ± 0.45%/year vs. -0.45 ± 0.19/year, P= 0.002). The VD reduction rate for the deep capillary plexus was not significantly different for the groups (P = 0.156). Conclusions The incident DR group experienced a significantly faster reduction in parafoveal VD in the SCP compared with the stable group. Our findings further provide supporting evidence that parafoveal VD in the SCP may be used as an early indicator of the pre-clinical stages of DR.

Comparison of Retinal and Choroidal Microvasculature Changes in Monocular Amblyopic and Non-amblyopic Eyes following Short-term Patch Occlusion Treatment

Purpose Our objective was to investigate whether there were differences in the short-term changes of retinal and choroidal microvasculature between amblyopic and non-amblyopic eyes after patch occlusion treatment in patients with monocular amblyopia. Additionally, we aimed to determine if these changes were associated with improvements in clinical parameters. Methods We conducted a retrospective, longitudinal paired-eye case-control study by analyzing the medical records of patients under the age of 12 who had monocular amblyopia and underwent patch occlusion treatment for a duration of 2 to 12 months. Using optical coherence tomography angiography images, we compared the foveal avascular zone width, retinal blood vessel density (VD), choroidal thickness (CT), and choroidal vascularity index (CVI) in amblyopic and non-amblyopic eyes before and after patch occlusion treatment. We analyzed the correlations between the aforementioned parameters and changes in best-corrected visual acuity (BCVA) and stereopsis. Results Overall, 114 eyes from 57 patients were enrolled. At baseline, parafoveal superficial plexus VD, foveal and parafoveal deep capillary plexus VD (DCPD) were lower by 0.994 ± 3.312% (p = .026), 2.403 ± 8.273% (p = .033), and 2.469 ± 4.095% (p < .001), respectively; CT was thicker by 30.6 ± 90.7 μm (p = .014); and CVI was higher by 1.920 ± 3.432% (p < 001) in the amblyopic eyes than in the non-amblyopic eyes. Following short-term patch occlusion treatment, foveal and parafoveal DCPD increased by 1.264 ± 3.829% (p = .017) and 1.028 ± 3.662% (p = .036), respectively, CT thinned by 15.5 ± 51.5 μm (p = .019), and CVI decreased by 1.296 ± 3.997% (p = .018) in the amblyopic eyes. Following patch occlusion treatment, as the foveal DCPD decreased and CVI increased, the BCVA improved (p = .017 and .035, respectively). Conclusion Following patch occlusion treatment, increased foveal DCPD and decreased CVI were associated with improved BCVA.

Association of OCT and OCT angiography measures with the development and worsening of diabetic retinopathy in type 2 diabetes.

To assess if optical coherence tomography (OCT) and OCT angiography (OCTA) measures are associated with the development and worsening of diabetic retinopathy (DR) over four years. 280 participants with type 2 diabetes underwent ultra-wide field fundus photography, OCT and OCTA. OCT-derived macular thickness measures, retinal nerve fibre layer and ganglion cell-inner plexiform layer thickness and OCTA-derived foveal avascular zone area, perimeter, circularity, vessel density (VD) and macular perfusion (MP) were examined in relation to the development and worsening of DR over four years. After four years, 206 eyes of 219 participants were eligible for analysis. 27 of the 161 eyes (16.7%) with no DR at baseline developed new DR, which was associated with a higher baseline HbA1c and longer diabetes duration. Of the 45 eyes with non-proliferative DR (NPDR) at baseline, 17 (37.7%) showed DR progression. Baseline VD (12.90 vs. 14.90 mm/mm2, p = 0.032) and MP (31.79% vs.36.96%, p = 0.043) were significantly lower in progressors compared to non-progressors. Progression of DR was inversely related to VD ((hazard ratio [HR] = 0.825) and to MP (HR = 0.936). The area under the receiver operating characteristic curves for VD was AUC = 0.643, with 77.4% sensitivity and 41.8% specificity for a cut-off of 15.85 mm/mm2 and for MP it was AUC = 0.635, with 77.4% sensitivity and 25.5% specificity for a cut-off of 40.8%. OCTA metrics have utility in predicting progression rather than the development of DR in individuals with type 2 diabetes.

Оценка макулярного кровотока с помощью оптической когерентной томографии-ангиографии у беременных женщин, страдающих сахарным диабетом

Purpose. To study retinal blood flow in pregnant women with disorders of carbohydrate metabolism using optical coherence tomography angiography (OCTA) in order to determine the criteria for the manifestation and progression of diabetic retinopathy (DR). Material and methods. 203 pregnant women in the third trimester were examined: 24 – with type 1 and 2 diabetes (T1D and T2D), 143 – with gestational diabetes (GD), and 36 apparently healthy women with physiological pregnancy, who consisted the control group. OCTA imaging was performed using the RTVue XR Avanti OCT 6 mm × 6 mm «Angio Retina» scan protocols (Optovue, USA). The whole image vessel density (wiVD), foveal vessel density (FVD), and foveal avascular zone (FAZ) area in the superficial capillary plexus were studied. Results. FVD in pregnant women with diabetes was significantly less than in pregnant women with GD and in the control group. In this connection, it can be assume changes of the retinal microvascular regulation, due to chronic disorders of carbohydrate metabolism in patients with diabetes, and development of microangiopathy. Enlargement of FAZ area and decrease of wiVD were revealed in patients with DR, relative to datas obtained in the group of pregnant women with diabetes and absence of DR, in the absence of differences in FVD indexes. In 2 patients with T1D and the absence of ophthalmoscopic signs of DR, OCTA revealed areas of nonperfusion in the posterior pole of the eye. Conclusion. OCTA helps to identify areas of retinal nonperfusion in the posterior pole of the eye in pregnant women with diabetes in the absence of ophthalmoscopic signs of DR and allows determining objective indications for timely retinal laser coagulation. Keywords: optical coherence tomography angiography, pregnancy, diabetic retinopathy, gestational diabetes, foveal avascular zone, retinal blood flow

Microvascular involvement in migraine: an optical coherence tomography angiography study.

The aim of this study was to evaluate the microvasculature of the macula and the optic nerve in patients affected by migraine with aura (MA) and without aura (MO) by optical coherence tomography angiography (OCTA), comparing the findings with healthy controls (HC). We collected data from ocular and orthotic examinations, including eye motility, intraocular pressure measurement, best-corrected visual acuity (BCVA) measurement, objective refraction measurement, fundus examination, macular and optic disk OCTA examination. All subjects were imaged with solix fullrange OCT. The following OCTA parameters were recorded: macular vessel density (VD), inside disc VD, peripapillary VD, disc whole image VD, fovea choriocapillaris VD, fovea VD, parafovea VD, peripapillary thickness, fovea thickness, parafovea thickness, macular full retinal thickness, and foveal avascular zone (FAZ) parameters. Clinical and demographical data about migraine patients were collected by a neurologist. We included 56 eyes from 28 patients with a diagnosis of MO, 32 eyes from 16 patients with a diagnosis of MA, and 32 eyes from 16 HC subjects. The FAZ area was 0.230 ± 0.099 mm2 in the MO group, 0.248 ± 0.091 mm2 in the MA group and 0.184 ± 0.061 mm2 in the control group. The FAZ area was significantly larger in the MA group than in the HC group (p = 0.007). The foveal choriocapillaris VD was significantly lower in MA patients (63.6 ± 2.49%) when compared with MO patients (65.27 ± 3.29%) (p = 0.02). An impairment of retinal microcirculation can be detected in patients with MA, as demonstrated by the enlargement of FAZ. Moreover, the study of choroid circulation may reveal microvascular damage in patients with migraine with aura. OCTA is a useful non-invasive screening tool for the detection of microcirculatory disturbance in patients with migraine.

Racial differences in quantitative optical coherence tomography angiography findings between older non-diabetics with co-morbidities.

This cross-sectional study compared optical coherence tomography angiography (OCTA) parameters between older Black and White adults with systemic comorbidities in an effort to further understand racial differences in the retinal microvasculature. We analyzed vessel density at the superficial (SCP), intermediate (ICP), and deep capillary plexuses (DCP), foveal avascular zone (FAZ) parameters, and blood flow area (BFA) at the choriocapillaris. We used a mixed-effects linear regression model, controlling for hypertension and two eyes from the same subject, to compare OCTA parameters. Black subjects had lower foveal vessel density at the SCP and ICP, while no differences were observed at the parafovea or 3x3 mm macular area of any capillary layer. Black subjects had greater FAZ area, perimeter, and FD-300, a measurement of vessel density in a 300 μm wide ring around the FAZ. Black subjects also had lower BFA at the choriocapillaris. Within a cohort of subjects without hypertension, these differences remained statistically significant, with the exception of foveal vessel density at the SCP and foveal BFA of the choriocapillaris. These findings suggest that normative databases of OCTA parameters must strive to be diverse in nature to adequately capture differences across patient populations. Further study is required to understand if baseline differences in OCTA parameters contribute to epidemiological disparities in ocular diseases.

Quantitative Measurements of Macular and Optic Nerve Head Blood Flow Parameters Following Cataract Surgery in Eye Department, Red Cross Tertiary General Hospital, Athens, Greece

Objective: To evaluate the effect of uncomplicated cataract surgery on macular and optic nerve head blood flow with Optical Coherence Tomography Angiography (OCT-A). Retinal vascular changes and macular vessel remodeling following cataract surgery is an area of interest, as the effect, cause and duration of such changes remain debatable.&#x0D; Setting: Eye Department, Red Cross Tertiary General Hospital, Athens, Greece.&#x0D; Methods: In this study, we recruited cataract surgery candidates who had regular post operative visits and underwent longitudinal OCT-A examinations before and after surgery.&#x0D; Results: Macular vessel density increased in the post operative visits both in the superficial (SCP) and deep capillary network (DCP) (P&lt;0.001) and showed a persistent effect over 3 months follow-up. Macular thickness increased over the first postoperative month, but returned to preoperative values at 3 months. Foveal avascular zone (FAZ) measurements and vessel density at radial peripapillary capillaries (RPC) were unaffected.&#x0D; Conclusions: OCT-A enables a quantitative analysis of blood flow by regular patient monitoring. In this study, we found that after cataract surgery, macular blood flow increased significantly. The reason for this could be attributed to post operative inflammatory process or vascular remodeling due to change in retinal metabolic demands.

Continuous Glucose Monitoring-Derived Metrics and Capillary Vessel Density in Subjects with Type 1 Diabetes without Diabetic Retinopathy.

Optical coherence tomography angiography (OCTA) is an innovative and reliable technique detecting the early preclinical retinal vascular change in patients with diabetes. We have designed our study to evaluate whether an independent relationship exists between continuous glucose monitoring (CGM)-derived glucose metrics and OCTA parameters in young adult patients with type 1 diabetes without diabetic retinopathy (DR). Inclusion criteria were age ≥ 18 years, diagnosis of type 1 diabetes from ≥ 1 year, stable insulin treatment in the last three months, use of real-time CGM, and CGM wear time ≥ 70%. Each patient underwent dilated slit lamp fundus biomicroscopy to exclude the presence of DR. A skilled operator performed OCTA scans in the morning to avoid possible diurnal variation. CGM-derived glucose metrics from the last 2 weeks were collected through the dedicated software during OCTA. Forty-nine patients with type 1 diabetes (age 29 [18; 39] years, HbA1c 7.7 ± 1.0%) and 34 control subjects participated in the study. Vessel density (VD) of the whole image and parafoveal retina in the superficial (SCP) and deep capillary plexus (DCP) was significantly lower in patients with type 1 diabetes compared to controls. The coefficient of variation of average daily glucose, evaluated by CGM, significantly correlated with foveal and parafoveal VD in SCP and with foveal VD in DCP. High glucose variability might be responsible for the early increase of VD in these areas. Prospective studies may help understand if this pattern precedes DR. The difference we detected between patients with and without diabetes confirms that OCTA is a reliable tool for detecting early retinal abnormalities.

Optical Coherence Tomography Angiography Assessment in Congenital Aniridia

This study aims to characterize foveal vasculature assessed by optical coherence tomography angiography (OCT-A) in congenital aniridia which is hallmarked by foveal hypoplasia (FH). Cross-sectional case-control analysis. At the National Referral Center for congenital aniridia, patients with confirmed PAX6-related aniridia and FH diagnosed on spectral-domain OCT (SD-OCT) with available OCT-A and matched control subjects were included. OCT-A was performed in patients with aniridia and control subjects. Foveal avascular zone (FAZ) and vessel density (VD) were collected. VD in the foveal and parafoveal areas at the level of the superficial and deep capillary plexi (SCP and DCP, respectively) were compared between the 2 groups. In patients with congenital aniridia, correlation between VD and the grading of FH was assessed. Among 230 patients with confirmed PAX6-related aniridia, high-quality macular B-scans and OCT-A were available in 10 patients. On the foveal area, mean VD was higher in aniridia patients (41.10%, n=10) than in control subjects (22.65%, n=10) at the level of the SCP and the DCP (P=.0020 and P=.0273, respectively). On the parafoveal area, mean VD was lower in patients with aniridia (42.34%, n=10) than in healthy subjects (49.24%, n=10) at the level of both plexi (P=.0098 and P=.0371, respectively). In patients with congenital aniridia, a positive correlation was found between the grading of FH and the foveal VD at the SCP (r=0.77, P=.0106). Vasculature is altered in PAX6-related congenital aniridia, higher in foveal and lower in parafoveal areas, especially when FH is severe, which is consistent with the concept that the absence of retinal blood vessels is essential for foveal pit development.

Assessment of macular microvascular changes in children following treatment of anisometropic myopic amblyopia using optical coherence tomography angiography

PurposeTo evaluate macular microvascular changes in the form of foveal avascular zone (FAZ) area and vessel density in the superficial, deep capillary plexuses, and choriocapillaris using optical coherence tomography angiography (OCTA) in children with anisometropic myopic amblyopia before and after treatment.MethodsThis prospective observational study included 32 patients younger than 12 years old with anisomyopic amblyopia. OCTA was done before patients’ treatment with optical correction with or without patching and was repeated after successful amblyopia treatment. Outcomes included superficial, deep, and choriocapillaris vessel density (VD) and superficial and deep FAZ areas.ResultsThe study included 13 males (40.6%) and 19 females (59.4%), and the mean age was 9.52 ± 1.33 years. Fifty-three percent (53%) of patients needed only optical correction, and the remaining 47% needed additional patching therapy. After successful treatment, there was a significant improvement in amblyopic eyes in best-corrected visual acuity (p < 0.001), with higher VD values in superficial capillary plexuses (p < 0.001), deep capillary plexuses (p < 0.001), and foveal choriocapillaris (p = 0.030). In the glasses with patching subgroup, the difference between pre-treatment and post-treatment parameters revealed a significant improvement in vessel density in superficial retinal plexuses (foveal and parafoveal; p values 0.023 and < 0.001, respectively) and deep retinal plexuses (whole image, foveal, and parafoveal; p values 0.003, < 0.001, and 0.002, respectively). While amblyopic eyes treated with glasses alone had a significantly greater difference in choriocapillaris foveal VD (p value = 0.022).ConclusionAfter effective amblyopia treatment, amblyopic eyes exhibited improved best-corrected visual acuity and better macular perfusion along the superficial, deep vascular density, and choriocapillaris foveal VD.Clinical trial registrationCinicalTrials.gov Identifier: NCT05223153.

Comparison of the vessel density measurements of the macula, optical disc, and peri-papillary region between ocular hypertension patients and healthy controls

ObjectiveTo evaluate Optical Coherence Tomography Angiography (OCT-A) findings in patients with Ocular Hypertension (OHT) and compare them with healthy individuals. MethodsThirty-four patients with ocular hypertension (OHT) and 22 healthy individuals were included in the study. Foveal thickness, retinal vascular density in superficial and deep capillary plexus and choriocapillaris, foveal avascular zone (FAZ), acircularity index (AI), foveal vessel density (FD), non-flow area, capillary and all vessel densities in the peripapillary area and the disc were automatically measured using the Angiovue software of OCT-A and compared between groups. ResultsThe comparison of the macular OCT-A findings did not reveal a significant difference between the two groups in terms of central macular thickness, superficial and deep capillary plexus vessel density (p>0.05). The foveal avascular zone width was significantly higher in OHT subjects compared to the control group (0.30±0.08 µ and 0.25±0.11 µ, respectively; p = 0.04). The comparison of optic nerve OCT-A findings revealed that the whole-field vessel density (wVD) (p = 0.007), peripapillary vessel density (pVD) (p = 0.001), inferior, superior and temporal radial peripapillary capillary plexus vessel density (p = 0.006, p = 0.008, p = 0.02) and the mean retinal nerve fiber layer thickness (p = 0.02) were significantly lower in the OHT group. ConclusionsOur findings suggest that the decrement in the optic disc vascular density and foveal avascular zone width was significantly higher in OHT subjects. The possible effect or role of these microvascular changes in terms of glaucoma development should be examined through further studies.

Long-Term Effect of SARS-CoV-2 Infection on the Retinal and Choroidal Microvasculature

The purpose of this study was to evaluate the persistent changes in microvascular parameters based on optical coherence tomography angiography (OCTA) in patients hospitalized due to COVID-19 bilateral pneumonia. The case-control prospective study was carried out among 49 patients with COVID-19 and 45 healthy age- and gender-matched 2 and 8 months after hospital discharge. We found a significantly decreased vessel density (VD) in superficial capillary plexus (SCP) in COVID-19 patients. Significantly decreased vessel density (VD) in the superficial capillary plexus (SCP), the deep capillary plexus (DCP), and choriocapillaris (CC), with significantly increased vessel density observed in the choriocapillaris in the foveal area (FCC). The foveal avascular zone in DCP (FAZd) was significantly increased in the COVID-19 group. We found differences between OCTA parameters according to gender. The foveal VD in SCP and DCP was significantly decreased in women compared to men. The FAZ area in SCP (FAZs) and superior VD in the choriocapillaris (SCC) were significantly increased in women. In conclusion, we noticed persistent changes in the ocular parameters of OCTA in COVID-19 patients. At the second follow-up visit, we observed a widened FAZ zone in SCP and decreased VD in some regions of the retina and choroid.

Is it useful to do OCTA in coronary artery disease patients to improve SYNTAX-based cardiac revascularization decision?

BackgroundTo investigate retinal and optic disk microcirculation using optical coherence tomography angiography (OCTA) in order to predict related outcomes based on the SYNergy between PCI with TAXUS and Cardiac Surgery (SYNTAX) score (SS) system in coronary artery disease patients. Methods104 patients were grouped based on coronary angiography results: 32 chronic coronary syndrome (CCS) patients, 35 acute coronary syndrome (ACS) patients, and 37 healthy controls. The SS system determined atherosclerosis degree and lesion-related mortality risk, followed by scoring as SYNTAX I score (SS-I) and SYNTAX II score (SS-II). Patients were further subdivided into SS-I, SS-II percutaneous coronary intervention (PCI), and SS-II coronary artery by-pass grafting (CABG) groups. Following a thorough ophthalmological examination, an OCTA Angio Retina mode (6 × 6 mm) automatically quantified retinal and optic disk microcirculation. ResultsThe mean ages did not differ significantly among groups (p = 0.940). The outer retinal select area varied significantly among groups, with the highest values found in ACS patients (p = 0.040). Despite non-significant differences between SS-I patients and healthy controls, the former had lower capillary plexus vessel densities in all regions and in foveal vessel density 300 μm around foveal avascular zone (FD-300) (p>0.05). Vessel densities were lowest in SS-II PCI≥28.5 patients, particularly in whole (p = 0.034) and parafoveal (p = 0.009) superficial capillary plexus, and in FD-300 (p = 0.019). Vessel densities were lowest in SS-II CABG (p = 0.020), and perifoveal (p = 0.017) deep capillary plexus, and in FD-300 (p = 0.003). The outer retina flow area increased the most in SS-II CABG≥25.1 patients (p = 0.020). ConclusionsUsing OCTA, a non-invasive imaging technique, to assess retinal and optic disk microcirculation appears to have the potential to yield significant clinical results in the early diagnosis or prognosis of cardiovascular diseases.

Inner retinal layers' alterations of the microvasculature in early stages of Parkinson's disease: a cross sectional study.

To investigate microcirculation characteristics of the inner retinal layers at the macula and the peripapillary area using Optical Coherence Tomography Angiography (OCT-A) of patients in early stages of Parkinson's disease (PD). 32 PD patients and 46 age- and gender-matched healthy controls were included in this cross sectional study. OCT-A imaging was performed to analyze microcirculation characteristics at each separate macular region (fovea, parafovea, and perifovea) and the peripapillary area of the inner retinal layers. Individuals with PD had significantly lower parafoveal, perifoveal and total vessel density (VD) in the superficial capillary plexus (SCP) than controls (all p < 0.001), while foveal VD was higher in PD eyes than that of controls, though not statistically significant. Similarly, individuals with PD had significantly lower parafoveal, perifoveal and total perfusion in the SCP than control eyes (all p < 0.001), while foveal perfusion was significantly higher in PD eyes than that of controls (p = 0.008). PD eyes had significantly smaller FAZ area and perimeter accompanied by decreased circularity at the SCP as compared to controls (all p < 0.001). Concerning the peripapillary area, individuals with PD had significantly lower radial peripapillary capillary perfusion density and flux index at the SCP than controls (all p < 0.001). All p values remained statistically significant even after using the Bonferroni correction for multiple comparisons, except for that of foveal perfusion. Our study indicates alterations of the inner retinal layers at the macula and the peripapillary area at the preliminary stages of PD. OCT-A parameters could potentially comprise imaging biomarkers for PD screening and improve the diagnostic algorithms.