Evaluation of macular and optic disc radial peripapillary vessel density with optical coherence tomography angiography in iron deficiency anemia

PurposeTo investigate effect of iron deficiency anemia (IDA) on macular and radial peripapillary capillary (RPC) vascular changes by optical coherence tomography angiography (OCTA).MethodsThirty-three patients with IDA and 33 healthy controls were enrolled in the study. Foveal avascular zone (FAZ) area, macular superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density and RPC vessel density were evaluated by the AngioVue Imaging System. Hemoglobin (Hb), hematocrit (Hct), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), red cell distribution width (RDW), serum iron, total iron-binding capacity (TIBC), serum ferritin and transferrin saturation values were also recorded.ResultsThere were no statistically significant differences between the two groups in terms of FAZ area and FAZ perimeter while foveal density (FD) was significantly decreased in the IDA group. Compared to control group, IDA group revealed significantly decreased macular vessel density in all macular regions except fovea in both SCP and DCP. RPC vessel density was significantly decreased in whole image, peripapillary and superior-hemifield area wihout RNFL thinning. Hemoglobin level was positively correlated with SCP whole and RPC whole vessel density and serum iron level was also positively correlated with SCP whole vessel density.ConclusionMacular and optic disc vessel density were reduced in IDA patients. OCTA may be useful in detecting retinal ischemia before clinically visible signs of retinopathy associated with IDA appear.     

Evaluation of the effect of obstructive sleep apnea syndrome on retinal microvascularity by optical coherence tomography angiography

PurposeUsing optical coherence tomography angiography (OCTA), we sought to determine whether there are retinal microvascular changes in patients with obstructive sleep apnea syndrome (OSAS).MethodThe study included 56 patients diagnosed with OSAS by polysomnography [21 patients with mild OSAS (group 1), 14 with moderate OSAS (group 2) and 21 with severe OSAS (group 3)], and 26 healthy individuals as a control group (group 4). The vascular densities of the superficial capillary plexus and deep capillary plexus of the retinal segmentations, together with the foveal avascular zone (FAZ) width, were measured for all participants, using OCTA.ResultCompared with the control group, vascular densitiy in whole image of superficial capillary plexus were found to be significantly lower in group 2. In addition, vascular densitiy in fovea region of superficial capillary plexus was significantly lower in group 1 than the control group. In deep capillary plexus, vascular densitiy of whole image, superior hemi and nasal regions were found to be significantly lower in group 2 and group 3 compared with the control group. Parafoveal region in group 3 had significantly lower vascular densities than the controls. A significantly larger FAZ was also found in group 1 and group 3 in the deep capillary plexus, compared with the controls.ConclusionWe detected smaller vascular densities in both the superficial capillary plexus and deep capillary plexus and a larger deep capillary plexus FAZ in OSAS patients. Therefore, OCTA may be useful as a non-invasive method to understand the systemic effects of OSAS.     

Normative data assessment of age-related changes in macular and optic nerve head vessel density using optical coherence tomography angiography

ObjectiveTo investigate macular and optic nerve head vessel density in healthy individuals using optical coherence tomography angiography (OCTA), and determine their relationship with age.MethodThis retrospective study included 153 eyes of 153 individuals aged between 20 and 80 years, who had no systemic diseases, optic disk, or retinal pathologies. The retinal (6 × 6 mm) and optic disk (4.5 × 4.5 mm) OCTA images were evaluated for superficial capillary plexus (SCP), deep capillary plexus (DCP) and radial peripapillary capillary plexus (RPCP) vessel density, foveal avascular zone (FAZ) area, and choriocapillaris flow area and compared among 5 age groups.ResultsThe SCP vessel density was significantly associated with age for the whole image (P = 0.001), parafovea (P = 0.038), and perifovea (P/ce:italic>= 0.001). The DCP vessel density significantly varied with age in the whole image (P = 0.004), parafovea (P = 0.001), and perifovea (P = 0.002). The SCP and DCP vessel densities were significantly lower in the older age groups, and more prominently so after 50 years of age. The FAZ area increased with age; however, this finding was not statistically significant (P = 0.660). The choriocapillaris flow area decreased with age (P = 0.002). The RPCP vessel density in the inside disk significantly decreased with age (P = 0.038).ConclusionAge should be taken into consideration when using OCTA in the diagnosis and follow-up of retinal and optic nerve diseases. It is believed that the results here in can be used as a reference baseline for future studies.     

Ozone-induced retinal vascular reactivity as assessed by optical coherence tomography angiography

BackgroundThis study aimed to investigate the retinal vascular reactivity (RVR) of the macular and peripapillary capillary network in response to ozonated autohemotherapy (AHT) using optical coherence tomography angiography (OCTA).MethodsThis was a single-centre prospective study. All participants that were planned to have a combination of major and minor ozone AHT underwent a complete ocular examination and OCTA imaging before and after the ozone AHT. Foveal avascular zone (FAZ) metrics and vessel density (VD) of superficial (SCP), deep capillary plexus (DCP), and radial peripapillary capillary (RPC) plexus were assessed using the built-in software.ResultsA total of 40 right eyes of 40 individuals were included. No significant differences were observed for the mean values of the FAZ metrics and choriocapillaris flow area following ozone AHT compared with baseline values (p > 0.05). The mean whole VD of SCP and DCP was 47.80 ± 2.18% and 53.09 ± 3.00% before treatment, which decreased to 47.68 ± 2.7% and 52.38 ± 3.07% after treatment (p = 0.660 and p = 0.097, respectively). No significant differences were observed in the vascular densities of both SCP and DCP in any quadrant (p > 0.05). The RPC density did not show significant alterations compared with baseline values, except the inferior-hemi region. The VD in the inferior-hemi peripapillary quadrant was significantly increased after ozone AHT (p = 0.034).ConclusionThe ozone AHT did not cause evident RVR in the macular area, whereas the peripapillary area showed a partial response.     

The role of optical coherence tomography angiography in reticular pseudodrusen

BackgroundTo investigate the changes in retinal and choriocapillaris vessel density (VD) in patients effected by early age-related macular degeneration (AMD) and reticular pseudodrusen (RPD), using Optical Coherence Tomography Angiography (OCTA).MethodsA total of seventy-eight eyes of 78 patients (43 male, 35 female, mean age 72.61 ± 5.15) with non-neovascular AMD (38 eyes with early AMD and 40 eyes with RPD) was recruited in this observational prospective study. Forty eyes of 40 healthy subjects represented the control group. The VD was measured in superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris in different macular regions.ResultsThere were no significant differences in VD of the SCP and DCP among the controls and the two study groups (p > 0.05). The VD of the choriocapillaris revealed a statistically significant reduction in early AMD and RPD groups respect to controls (p < 0.001). Furthermore, the patients with RPD showed a significantly decreased VD respect to patients with early AMD in different macular regions (p < 0.001).ConclusionsThe quantitative analysis of retinal and choriocapillaris blood flow by OCTA provided useful information regarding the vascular changes in non-neovascular AMD patients suggesting that the choriocapillaris loss is mainly involved in the pathogenesis of RPD.     

Choriocapillary regional characteristics in idiopathic macular holes using optical coherence tomography angiography

Purpose: To evaluate the characteristics of vascular density (VD) of the retinal capillary plexuses in idiopathic macular hole (IMH), the fellow eye, and healthy control eyes by optical coherence tomography angiography (OCTA).Methods: A retrospective cases series study involving 20 unilateral eyes (20 patients) with IMH, the unaffected fellow eyes (n = 20) and 20 health controls, with age- and sex-matched, was conducted in Shanxi Eye Hospital from January 2019 to December 2021. VD of the retinal capillary plexuses measurements were obtained by OCTA.Results: Four quadrants of superficial capillary plexuses (SCP) in IMH eyes were not significant compared with that in the unaffected fellow eyes (all P > 0.05). The four quadrants of deep capillary plexuses (DCP) in IMH eyes were lower than that in the unaffected fellow eyes (all P < 0.05). Different regions retinal thickness in the IMH eyes was higher than that in the unaffected fellow eyes (all P < 0.05). a significant negative correlation between deep vessel density and retinal thickness in different quadrants among IMH eyes (all P < 0.05). Additionally, the correlation between the vascular density of SCP and retinal thickness was significant in macular fovea area (= 0.519, P = 0.019). <0.001.Conclusions: The morphology of retina and choroid in idiopathic macular hole is different from that in fellow eye. The thickness of choroid in the fovea area of the unaffected eye also showed a decreasing trend. Taken together, the mechanism of macular hole may be further understood, that is, the decrease of choroid thickness may occur before the macular hole formation. It was verified again that the choroidal blood flow area in macular fovea of IMH patients was significantly lower than that in fellow eyes and healthy eyes.     

OCT and OCTA evaluation of vascular and morphological structures in the retina in recovered pediatric patients with COVID-19

BackgroundUsing OCT and OCTA imaging, we aimed to determine whether COVID-19 induces pathological changes in vascular and morphological structures in the pediatric retina.MethodsThe current prospective, cross-sectional, observational clinical study included recovered pediatric patients with COVID-19 evaluated between May 2020 and June 2020. Retinal vascular (radial peripapillary, superficial, and deep capillary plexus vessel densities) and morphological (peripapillary retinal nerve fiber, ganglion cell layer, retinal, and choroidal thickness) in the optic disk and macula regions were quantitively assessed using OCT and OCTA. Data were compared between COVID-19 patients and age-matched controls.ResultsThe COVID-19 group included 32 eyes of 16 patients and the control group included 32 eyes of 16 cases. Fundus and biomicroscopic examinations revealed no signs of pathology in the COVID-19 group. Mean peripapillary retinal nerve fiber, ganglion cell layer, and choroidal thickness values were significantly greater in the COVID-19 group than in the control group (p<0.05). OCTA indicated that mean superficial and deep capillary plexus vessel densities, and choriocapillaris flow area values were significantly lower in the COVID-19 group than in the control group, whereas mean radial peripapillary capillary plexus vessel density values were significantly higher (p<0.05).ConclusionsEven if fundus examination results appear normal in pediatric patients with COVID-19, vascular and morphological changes may be observed in the retina. Further studies with larger numbers of patients are needed to elucidate the clinical significance of vascular and morphological changes in this population.     

Foveal avascular zone in normal human eyes by optical coherence tomography angiography

ObjectiveTo analyze the influence factors of the area of superficial plexus foveal avascular zone (FAZ) and related indexes of fovea measured with optical coherence tomography angiography (OCT-A) in normal subjects.MethodsThis was a cross-sectional study from November 2020 to May 2021 in the Inner Mongolia Autonomous Region, China. Each subject received related eye examination. The correlation between all the factors and superficial plexus FAZ were analyzed under univariable and multivariable linear regression analysis.ResultsFinally, 239 subjects with sufficient data were recruited in the study, including 108 males and 131 females, aged 27.41±4.63 years. The area of superficial plexus FAZ was 0.33±0.16 mm². In the univariate regression, gender (β = 41.702, 95%CI: 9.152 to 74.253, P = 0.012), drinking (β = -66.074, 95%CI: -99.197 to -32.951, P = 0.001) and axial length (β = -15.874, 95%CI: -29.562 to -2.185, P = 0.023) were associated with superficial plexus FAZ area. In multivariate regression analysis results, drinking (β = -42.410, 95%CI = -79.388 to -5.432, P = 0.025) was significantly correlated with superficial plexus FAZ area.ConclusionThe area of superficial plexus FAZ was not affected by age, gender, systematical and biochemical indicators, but related to the status of drinking.     

Retinal microvascular changes in patients recovered from COVID-19 compared to healthy controls: A meta-analysis

PurposeTo investigate changes in retinal microcirculation in patients recovered from COVID-19 infection compared to healthy controls, using optical coherence tomography-angiography.MethodsMeta-analysis of eligible studies comparing retinal microcirculation between patients recovered from COVID-19 infection and healthy controls up to 7th of September 2022 was performed, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2009 guidelines. The following search algorithm was used: (COVID-19 OR coronavirus) AND (retina OR optical coherence tomography OR optical coherence tomography angiography OR vessel density OR foveal avascular zone). Standardized Mean Difference (SMD) with 95% confidence interval (CI) was calculated to compare continuous variables. Revman 5.3 was used for the analysis.Results12 studies were included in our analysis. Foveal avascular zone (FAZ) area was larger in patients recovered from COVID-19 infection compared to healthy controls, while there was no statistically significant difference in FAZ perimeter between the two groups. The foveal, parafoveal and whole image vessel density in the superficial capillary plexus showed no significant difference between the two groups. The foveal, parafoveal and whole image vessel density in the deep capillary plexus was statistically lower in patients recovered from COVID-19 compared to healthy controls.ConclusionFAZ area was enlarged and foveal, parafoveal and whole image vessel density in deep capillary plexus were reduced in patients recovered from COVID-19 infection compared to healthy controls, suggesting that COVID-19 infection may induce long-term retinal microvascular changes in patients recovered from the virus infection.     

Association between macular and papillary vessel density by optical coherence tomography angiography in a large healthy population

PurposeTo provide a normative data set of the relationship between macular and papillary vessel density (VD) using swept-source optical coherence tomography angiography (SS-OCTA) in a large healthy population.MethodsCross-sectional study conducted on 346 right eyes of healthy subjects. Macular and papillary SS-OCTA VD measurements of the retinal superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris (CC) in the central area and the four quadrants were obtained. Correlations between macular and papillary VD among different quadrants were assessed.ResultsThe mean participant age was 37.7 ± 19.8 years (range 5–83); 59% were women. No correlation was detected neither for the global SCP (R = 0.050; P = 0.040), DCP (R = -0.056; P = 0.038) nor CC (R = 0.102; P < 0.001) between macular and papillary VD. In a subanalysis, there was also no correlation in any of the quadrants studied (R ≤ 0.180; P < 0.001). In a subgroup of 45 left eyes, there was no correlation in the different plexus and layers studied between macular and papillary vasculature. No differences in SCP, DCP and CC were found according to gender, age or axial length in the relationship between macular and papillary VD.ConclusionThere is no association between macular and papillary VD neither in the SCP, DCP or CC in any of the regions studied. Hence, macular and optic nerve head vascularization should be investigated separately to identify which structure is more relevant in each disease.     

Quantitative assessment of retinal vessel density and thickness changes in internal carotid artery stenosis patients using optical coherence tomography angiography

ObjectiveTo quantitatively assess the retinal features of patients with different degrees of internal carotid artery stenosis (ICAS), particularly mild ICAS patients, utilizing optical coherence tomography angiography (OCTA).MethodsThirty-two mild ICAS patients (mild ICAS group), 34 moderate to severe ICAS patients (nonmild ICAS group), and 40 controls were enrolled in this study. Retinal vessel density was quantitatively measured by OCTA, including radial peripapillary capillary vessel density (RPC-VD), superficial and deep capillary plexus vessel density (SCP/DCP-VD). Structural parameters were collected from optical coherence tomography (OCT), including retinal thickness and subfoveal choroidal thickness (SFCT). Furthermore, LASSO-penalized logistic regression was used to construct the diagnostic model based on retinal parameters. ROC curves and nomogram plots were used to assess the diagnostic ability of this model for ICAS.ResultsThe macular SCP-VD of mild ICAS patients was significantly lower than that of controls and lower than that of nonmild ICAS patients (all p < 0.05). However, there was no difference among the three groups in terms of DCP-VD (p > 0.05). RPC-VD could effectively discriminate between the mild ICAS group and the nonmild ICAS group (p = 0.005). For structural OCT, only the SFCT decreased as the ICAS degree increased (p < 0.05). Diagnostic scores based on retinal parameters showed a strong diagnostic capability for mild ICAS (AUC = 0.8656).ConclusionMild ICAS patients exhibited distinct retinal features compared to nonmild ICAS patients and control subjects. OCTA potentially represents a promising method for the early detection of ICAS patients and the noninvasive surveillance of haemodynamic changes in those patients.     

The assesment of retina and optic disc vascular structures in people who received CoronaVac vaccine

IntroductionSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus that is responsible for the current coronavirus disease pandemic and the vaccines currently developed are administered to prevent this infection. CoronaVac is a vaccine produced by the inactivated virus method. Ocular side effects such as anterior uveitis, optic neuritis, vision loss, episcleritis, allergic reaction and paracentral acute middle maculopathy have been reported after receiving CoronaVac vaccine. We assume that with this study, we can identify potential changes in posterior segment structures and posterior segment vascular density of people who received CoronaVac vaccine with optical coherence tomography angiography (OCTA) device.Material methodForty healthcare professionals who applied to the Health Sciences University Antalya Training and Research Hospital Ophthalmology Clinic for routine eye control were included in the study. The subjects who do not have any systemic condition and would be administered CoronaVac vaccine were chosen to assess. OCTA images of the patients before and within 1 week after vaccination were captured, then retinal and optic disc vascular values, foveal avascular zone (FAZ), choriocapillary blood flow (CBF), subfoveal choroidal thickness (SCT) and retinal thickness were analyzed and compared.ResultsTwo of the 40 patients had burning and stinging in the eye (5%), two of the 40 patients had redness (5%) and itching (5%) in the eye. 36 patients did not have any ocular symptoms.No statistically significant difference was found in the retinal and optic disc vascular density values, FAZ, CBF, SCT and retinal thickness values ​​of the patients before and after vaccination.ConclusionThis is among the first studies in the literature to evaluate the changes in retinal and optic disc vascular values ​​in people who received CoronaVac vaccine. In this study, we observed that CoronaVac vaccine did not effect retinal and optic disc vascular density significantly.     

The association between decreased choriocapillary flow and electroretinogram impairments in patients with diabetes

PurposeTo evaluate the association between choriocapillary flow (CCF) and electroretinogram (ERG) in patients with diabetes.MethodThis was a cross-sectional study. Patients with type 2 diabetes and healthy controls who had undergone both flicker ERG and optical coherence tomography angiography (OCTA) were included, while patients with severe diabetic retinopathy (DR) and macular edema were excluded. Correlations among OCTA and ERG parameters were conducted by generalized linear mixed models (GLMM).ResultOne hundred ninety-four eyes of 102 patients with diabetes and fifty-six eyes of 28 controls were included. The implicit time of 30-Hz flicker ERG successively increased, while the amplitudes, inner-retina vessel density and CCF were decreased from the control to the nondiabetic retinopathy (NDR) to DR group. In patients with diabetes, all GLMM models of ERG parameters had statistically significance (P<0.05), and CCF was correlated with ERG parameters (coefficient index=-0.601, P< 0.001 with 16 Td-s implicit time; coefficient index=-0.687, P< 0.001 with 32 Td-s implicit time; coefficient index=0.933, P=0.035 with 32 Td-s amplitude) and the thickness of retinal pigment epithelium, while in the GLMM model of CCF, it was correlated with the thickness of retinal pigment epithelium and the level of glycosylated hemoglobin(both P= 0.001).ConclusionCCF decreased in patients with diabetes, and it was related with ERG. Choroidopathy and its functional impairment in the retina may occur very early in patients with diabetes by influencing the outer retina.     

Evaluation of peripapillary - macular microvascularity and choroidal vascularity index after refractive surgery

BackgroundTo evaluate the microvascularity and choroidal vascularity index (CVI) using optical coherence tomography angiography (OCTA) and OCT following femtosecond laser-assisted in-situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) procedures.MethodsPatients with myopia (<-6.0D sphere) or myopic astigmatism (<-4.0D astigmatism) were enroled. The percentage of vessel density and foveal avascular zone (FAZ) size, optic disc flux index and perfusion were noted and the CVI was calculated before and after surgery.ResultsTwenty-nine eyes of 16 patients in the FS-LASIK group and 30 eyes of 16 patients in the SMILE group were enroled. Macular vessel density, FAZ size, and optic disc flux index were significantly higher on postoperative 1st day compared to preoperative day (p = 0.001, p = 0.007, and p < 0.001, respectively). There was no significant difference in terms of macular and peripapillary CVI between postoperative 1st day and preoperative day (p > 0.05). All microvascular parameters were similar on postoperative 7th day and preoperative day (p > 0.05).ConclusionsIt was detected that there is a transient alteration in macular and peripapillary microvascularity after FS-LASIK/SMILE, whereas choroidal circularity is not significantly affected by these refractive surgeries.     

Impacts of Glycemic Control on Intracranial Plaque in Patients with Type 2 Diabetes Mellitus: A Vessel Wall MRI Study

BACKGROUND AND PURPOSE:The relationship between glycemic control in patients with type 2 diabetes mellitus and intracranial atherosclerotic plaque features has remained understudied. This study aimed to investigate the association of type 2 diabetes mellitus and glycemic control with the characteristics of intracranial plaques using vessel wall MR imaging.MATERIALS AND METHODS:In total, 311 patients (217 [69.8%] men; mean age, 63.24 ± 11.44 years) with intracranial atherosclerotic plaques detected on vessel wall MR imaging were enrolled and divided into 3 groups according to type 2 diabetes mellitus and glycemic control statuses: the non-type 2 diabetes mellitus group, the type 2 diabetes mellitus with good glycemic control group, and the type 2 diabetes mellitus with poor glycemic control group. The imaging features of intracranial plaque were analyzed and compared among the groups. The clinical risk factors for atherosclerosis were also analyzed using logistic regression analysis.RESULTS:The plaque length and thickness were significantly higher in the type 2 diabetes mellitus with poor glycemic control group than in the non-type 2 diabetes mellitus group. The prevalence of strongly enhanced plaques was significantly higher in the type 2 diabetes mellitus with poor glycemic control group than in the non-type 2 diabetes mellitus and type 2 diabetes mellitus with good glycemic control groups (92.9%, 63.4%, and 72.7%, respectively; P < .001). Multivariate logistic regression analysis showed a significant association of poor glycemic control with the plaque length (OR = 1.966; 95% CI, 1.170–3.303; P = .011), plaque thickness (OR = 1.981; 95% CI, 1.174–3.340; P = .010), and strongly enhanced plaque (OR = 5.448; 95% CI, 2.385–12.444; P < .001).CONCLUSIONS:Poor glycemic control, compared with the history of diabetes, might have a greater impact on the burden and vulnerability of intracranial atherosclerotic plaques.

Type 2 diabetes mellitus (T2DM) is a highly prevalent disease associated with an increased risk of coronary artery disease, peripheral artery disease, and cerebrovascular disease, which are major causes of mortality.¹ Diabetes alters the function of multiple cell types, including the endothelium, smooth muscle cells, and platelets, thus contributing to atherosclerosis and its complications.^2-4 Diabetes also increases the breakdown and decreases the synthesis of collagen, so that the stability of the plaque fibrous cap may decrease and the plaques may rupture more readily.⁴The association between glycemic control and extracranial atherosclerosis in patients with T2DM has been extensively investigated.^5-7 Patients with T2DM or poor glycemic control have a predisposition to a higher burden and vulnerability of extracranial atherosclerotic disease. Compared with the extracranial arteries, intracranial arteries exhibit different histologic features, including denser internal elastic lamina, thinner media, less abundant adventitia, only a few elastic fibers, without an external elastic lamina.^8,9 These unique histologic structures of the intracranial arteries may lead to different characteristics of intracranial atherosclerosis (ICAS) compared with extracranial atherosclerosis. However, few studies have analyzed the association between glycemic control and the properties of intracranial atherosclerotic plaques in patients with T2DM.In recent years, high-resolution vessel wall (VW) MR imaging has been used to demonstrate the characteristics of intracranial plaques, including plaque morphology, plaque components, and inflammation.¹⁰ In this study, the association between glycemic control and characteristics of intracranial atherosclerotic plaques in patients with T2DM was investigated by imaging plaques with VW MR imaging. The risk factors for the heavy burden and vulnerability of intracranial atherosclerotic plaques in patients with T2DM were also investigated. The findings of this study provided novel insights into the role of glycemic control status of patients with T2DM in the progression of ICAS, which, in turn, provided necessary information to educate patients about the importance of glycemic control.     

Optical coherence tomography angiography findings in transfusion-dependent beta-thalassemia patients with and without splenectomy

BackgroundOcular involvement is common in transfusion-dependent beta-thalassemia (TDβ-T) patients. We aimed to investigate the effect of splenectomy on optical coherence tomography angiography (OCTA) findings in TDβ-T patients.MethodsThe study is a prospective cross-sectional study. A total of 45 eyes of 23 patients with splenectomy (34.04±8.83 years), 18 eyes of 9 patients without splenectomy (27.44±5.43 years), and 54 eyes of 27 controls (33.22±6.44 years) were included. Vessel density in superficial capillary plexus, deep capillary plexus and radial peripapillary capillary, foveal avascular zone, choriocapillaris flow area, choroidal and retinal thickness detected by OCTA were evaluated. p < 0.05 was considered significant.ResultsVessel density of superficial capillary plexus and deep capillary plexus were similar in patients with and without splenectomy, and controls. Choriocapillaris flow area was significantly decreased in patients with splenectomy than that in those without splenectomy and controls (2.02±0.12 vs. 2.17±0.1 and 2.14±0.12; p < 0.001). Choroidal thickness was significantly lower in patients without splenectomy than in patients with splenectomy and controls (260.05±61.02 vs. 305.11±42.13 and 298.89±29.14, p = 0.008). Parafoveal and perifoveal thickness of the full retina and outer retina were significantly lower in patients without splenectomy than in patients with splenectomy and controls (301.06±10.0, 279.78±10.28 vs. 311.04±14.89, 290.87±13.67 and 316.63±13.57, 289.56±9.31, p < 0.001 and p = 0.002; 174.72±7.81, 167.17±6.21 vs. 182.87±8.81, 173.60±7.09 and 185.11±9.26, 173.96±6.79, p = 0.001 and p < 0.001, respectively).ConclusionsOCTA findings can provide information about the microvascular effects of splenectomy on the retina of patients with TDβ-T.     

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.     

Investigation of changes in retinal vascular parameters and choroidal vascular index values during the early recovery period of COVID-19: The COVID-OCTA study

BackgroundCOVID-19 effects microvasculature in many tissues. This study investigated whether the choroidal structure is also affected.MethodsThis cross-sectional study included 80 patients with COVID-19 and the same number of age- and gender-matched healthy individuals. All participants' right eye measurements were examined. Optical coherence tomography angiography (OCTA) was used for imaging. Otherwise, two independent researchers used the Choroidal vascular index (CVI) for choroidal parameters calculation.ResultsSuperior and deep flow values were lower in the COVID-19 group than in the control group, and vascular density (VD) values were lower in all regions in this group. Except for the superior mean VD, there was no statistically significant difference (p = 0.003). However, the COVID-19 group had significantly lower subfoveal choroidal thickness (SFChT) measurements than the control group (p = 0.001). In addition, no significant difference was observed between the groups in evaluating mean CVI values (p>0.05).ConclusionNoninvasive diagnostic tools such as OCTA and EDI-OCT can be used to monitor early changes in diseases affecting microvessels, such as from COVID-19.     

Associations between body mass index and choroidal thickness,superficial and deep retinal vascular indices,and foveal avascular zone measured by OCTA

AimThe present study explores the effects of Body Mass Index (BMI) on choroidal thickness, the deep and superficial retinal capillary plexuses, and the foveal avascular zone (FAZ).MethodsThe subjects in this prospective study were divided into five groups based on their calculated BMI. Choroidal thickness, superficial and deep retinal capillary plexuses, and FAZ were measured using enhance depth imaging (EDI) and optical coherence tomography angiography (OCTA). The groups were then compared and correlations with BMI were evaluated.ResultsThe study included 210 eyes of 105 subjects. The comparison of the BMI groups revealed a significant decrease in the mean choroidal thicknesses in the obese groups (p = 0.001), and a significant negative correlation between BMI and mean choroidal thickness (p = 0.02). The results of the analysis of the mean superficial and deep retinal capillary plexuses did not differ between the groups (p = 0.089, p = 0.808 respectively), while the deep FAZ measurements revealed a significant decrease in the obese groups (p = 0.003).ConclusionChoroidal thickness and deep FAZ are significantly negatively correlated with BMI, suggesting potential choroidal and retinal microvascular effects of obesity.