Capillary Plexus Vessel Density Research Articles

Investigation of the effects of single and two-muscle horizontal rectus surgeries on macular microvasculature.

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 30days 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 ± 6.75years (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.

Effect of Buerger’s disease on ocular microvascular structure

ABSTRACT Clinical relevance Buerger’s disease, being a systemic inflammatory vasculopathy, may present with ocular findings. Background This study aims to understand the potential role of optical coherence tomography and angiography findings in evaluating the course of Buerger’s disease. Methods This was a prospective, cross-sectional study that included 25 patients with Buerger’s disease (Group 1) and 51 healthy control participants, of whom 27 were smokers (Group 2) and 24 were non-smokers (Group 3). Following a detailed ophthalmic examination, optical coherence tomography and angiography measurements were conducted on participants. The values of macular superficial and deep capillary plexus, peripapillary capillary plexus vessel density measurements were taken into account from optical coherence tomography angiography measurements. Furthermore, measurements were taken for the parameters of the foveal avascular zone, including its area, perimeter and acircularity index. Additionally, the choriocapillaris flow area was assessed between radii of 1 mm, 2 mm, and 3 mm. Results In patients with Buerger’s disease, the area and perimeter of the foveal avascular zone were higher than in both smoker and non-smoker healthy groups (p < 0.001 for all). The vessel densities in superficial capillary plexus were found to be lower in patients with Buerger’s disease compared to both smokers and non-smokers in all regions except the parafovea (p < 0.05 for all). The radial peripapillary capillary plexus vessel densities in the whole retina and peripapillary region were lower than those in the non-smoker group (p < 0.001 and p = 0.008). The choriocapillaris flow areas in all three radius were lower in the smoker group than in the non-smoker group (1 mm, p = 0.01; 2 mm, p = 0.005; 3 mm, p = 0.011) Conclusions Buerger’s disease extends beyond the extremities, affecting vascular density and tissue perfusion in the optic disc and macula, making it a systemic condition. This disease can have ocular involvement without causing serious ocular findings.

Optical coherence tomography angiography evaluation of retinal and choroidal microvascular changes in pregnant women with a history of unexplained recurrent spontaneous abortions.

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. 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). 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). 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.

Choroidal and retinal vascular changes in HLA-B27-associated anterior uveitis.

To quantitatively analyze choroidal and retinal vascular changes in HLA-B27-associated anterior uveitis. A retrospective study. Medical records of 51 eyes with unilateral HLA-B27-associated anterior uveitis, their fellow eyes and 47 sex and age-matched healthy eyes were retrospectively reviewed. Their choroidal and retinal vasculature were analyzed using swept-source (SS) optical coherence tomography (OCT) and OCT angiography (OCTA) scans. Deep capillary plexus (DCP) vessel density (VD) (p < 0.001), choroidal vascularity index (CVI) (p = 0.012), and choriocapillary flow deficit (CCFD) (p < 0.001) of uveitic and fellow eye group were significantly higher than those of control group. On the contrary, superficial capillary plexus (SCP) VD (p < 0.001) of uveitic and fellow eye group were significantly lower than of control group. The vascular parameters of uveitis and fellow eye group showed no significant difference between uveitic and resolution period. Certain choroidal and retinal vascular parameters were significantly changed in both HLA-B27-associated anterior uveitis without posterior segment involvement and the quiet fellow eyes, suggesting their possible effects as a systemic inflammatory disorder.

Assessment of OCT-Based Macular Curvature and Its Relationship with Macular Microvasculature in Children with Anisomyopia.

To evaluate the intraocular differences in optical coherence tomography (OCT)-based macular curvature index (MCI) among children with anisomyopia and to investigate the relationship between MCI and the macular microvasculature. Fifty-two schoolchildren with anisometropia > 2.00 D were enrolled and underwent comprehensive examinations including cycloplegic refraction, axial length (AL), and swept source OCT/OCT angiography. OCT-based MCIs were determined from horizontal and vertical B-scans by a customized curve fitting model in MATLAB R2022 at 1-mm-, 3-mm-, and 6-mm-diameter circles at fovea. Characteristics and topographic variation of MCI was analyzed, and the relationships with microvascularity and its associated factors were investigated. MCI achieved high reliability and repeatability. There were overall larger MCIs in the more myopic eyes than the less myopic eyes in 1-mm-, 3-mm-, and 6-mm-diameter circles at fovea (all p < 0.001). For the topographic variation, horizontal MCI was significantly greater than vertical MCI (all p < 0.001), and was the largest in 6-mm circle, followed by 3-mm and 1-mm circles. Stronger correlation of horizontal MCI with myopic severity than vertical MCI was found. Partial Pearson's correlation found MCI was negatively associated with deep capillary plexus (DCP) vessel density (p = 0.016). Eyes with a higher MCI in a 6-mm circle were more likely to have longer AL (p < 0.001), lower DCP vessel density (p = 0.037), and thinner choroidal thickness (ChT) (p = 0.045). Larger MCI was found in the more myopic eyes of children with anisomyopia and was significantly associated with smaller DCP density, suggesting that MCI was an important indicator of myopia-related retinal microvascularity change, and it could be a valuable metric for myopia assessment in children.

Longitudinal Assessment of Intraretinal Microvascular Abnormalities in Diabetic Retinopathy Using Swept-Source Optical Coherence Tomography Angiography.

To longitudinally investigate the changes in intraretinal microvascular abnormalities (IRMAs) over time, employing swept-source optical coherence tomography angiography in eyes with diabetic retinopathy. In this retrospective, longitudinal study, we evaluated 12 × 12-mm swept-source optical coherence tomography angiography centered on the macula at baseline and last available follow-up visit for (1) IRMA changes during follow-up, defined as (a) stable, (b) regressed, (c) obliterated, and (d) progressed; and the (2) development of new neovascularization (NV) and their origins. Competing-risk survival analysis was used to assess the factors associated with these changes. In total, 195 eyes from 131 participants with diabetic retinopathy were included. Stable, regressed, obliterated, and progressed IRMA were observed in 65.1%, 12.8%, 11.3%, and 19% of eyes with diabetic retinopathy, respectively. Anti-VEGF injections during the follow-up periods and a slower increase of foveal avascular zone were associated with IRMA regression (P < 0.001 and P = 0.039). Obliterated IRMA were correlated with previous panretinal photocoagulation (P < 0.001) and a lower deep capillary plexus vessel density at baseline (P = 0.007), as well as with follow-up anti-VEGF injections (P = 0.025). A higher baseline ischemia index (ISI) and panretinal photocoagulation during the follow-up periods were associated with IRMA progression (P = 0.049 and P < 0.001). A faster increase in ISI predicted the development of NV elsewhere (NVE) from veins (P < 0.001). No significant factors were found to be associated with NVE originating from IRMA. Changes in IRMA closely correlated with the severity of retinal ischemia and treatment. Notably, our study confirmed the potential, yet relatively rare, development of NVE from IRMA in a large cohort; however, the risk factors associated with this transformation require further exploration.

Race/Ethnicity Analysis of Vascular Alterations in Optical Coherence Tomography Angiography in Diabetic Patients

ABSTRACT Purpose Racial and ethnic minorities have a higher prevalence of diabetic retinopathy (DR) and present at advanced stages of disease. In an urban hospital population, we investigated microvascular differences in optical coherence tomography angiography (OCTA) between racial/ethnic groups while adjusting for socioeconomic status (SES). Methods 3 × 3 mm2 macular OCTA scans were obtained for analysis of foveal avascular zone (FAZ) area, FAZ perimeter as well as superficial (SCP) and deep capillary plexus (DCP) vessel density (VD), vessel length density (VLD), and adjusted flow index (AFI). SES was measured using the Area Deprivation Index. Multivariable regression models were used to adjust estimates for relevant confounders. Results 217 non-diabetic and 1,809 diabetic patients were included in the study, consisting of 42.2% Hispanic, 24.9% non-Hispanic (NH) Asian, 6.8% NH Black, 9.7% NH White and 16.3% Other patients. NH White was used as the reference group. Hispanic, NH Asian, and NH Black patients had significantly greater FAZ areas and FAZ perimeters, and lower DCP VD and VLD, among both non-diabetic and diabetic patients (Benjamini-Hochberg adjusted P-values <0.05). The addition of SES scores in the models did not modify any regressions significantly. Conclusions In patients with and without diabetes, racial and ethnic minorities have significant retinal microvasculature differences when compared to NH White patients, regardless of SES. These differences are pronounced in DCP and may predispose racial/ethnic minorities to worse outcomes in DR, thus widening disparities in ophthalmic care.

CHANGES IN OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY MEASURES THROUGHOUT THE DAY: Diurnal Variation or Test-Retest Variability?

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

Optical coherence tomography angiography for the assessment of retinal microvasculature characteristics in preterm-born children: A systematic review and meta-analysis.

This study aimed to evaluate the usefulness of optical coherence tomography angiography (OCTA) in assessing retinal microvascular structural changes in preterm-born children and compare them with those in term-born children. The Web of Science Library, Cochrane Library, PubMed, Embase, CNKI, Wanfang, VIP, and Sino Med databases were searched systematically to extract studies published till April 25, 2023. Two independent reviewers searched all the literature and completed the data extraction and quality assessment. Mean differences (MDs) with 95% confidence intervals (CIs) were used to assess the continuous estimates. STATA software (v15.1; StataCorp, College Station, TX) was used to analyze the data. Twelve published studies were eligible for inclusion in this study. The meta-analysis revealed that the foveal avascular zone (FAZ) area of preterm-born children was remarkably smaller than that of term-born children, with the laser photocoagulation (LP)-ROP group showing the most pronounced reduction. The foveal superficial capillary plexus vessel density (SCP-VD) and deep capillary plexus vessel density (DCP-VD) were remarkably higher in the preterm-born group than in the control group, with variations in subgroups (LP-ROP, anti-VEGF-ROP, SR-ROP, and Pre-T-ROP). The parafoveal SCP-VD was remarkably lower in preterm-born children compared to that of the controls, while no significant difference was identified in the parafoveal DCP-VD. Preterm-born children had a smaller FAZ area, higher foveal SCP-VD and DCP-VD, and lower parafoveal SCP-VD compared to their term-born counterparts. The parafoveal DCP-VD did not differ substantially between preterm- and term-born children. OCTA is an effective modality for assessing alterations in the retinal microvasculature in preterm children.

Imaging the Retinal Vascular Mural Cells In Vivo: Elucidating the Timeline of Their Loss in Diabetic Retinopathy.

Vascular mural cells (VMCs) are integral components of the retinal vasculature with critical homeostatic functions such as maintaining the inner blood-retinal barrier and vascular tone, as well as supporting the endothelial cells. Histopathologic donor eye studies have shown widespread loss of pericytes and smooth muscle cells, the 2 main VMC types, suggesting these cells are critical to the pathogenesis of diabetic retinopathy (DR). There remain, however, critical gaps in our knowledge regarding the timeline of VMC demise in human DR. In this study, we address this gap using adaptive optics scanning laser ophthalmoscopy to quantify retinal VMC density in eyes with no retinal disease (healthy), subjects with diabetes without diabetic retinopathy, and those with clinical DR and diabetic macular edema. We also used optical coherence tomography angiography to quantify capillary density of the superficial and deep capillary plexuses in these eyes. Our results indicate significant VMC loss in retinal arterioles before the appearance of classic clinical signs of DR (diabetes without diabetic retinopathy versus healthy, 5.0±2.0 versus 6.5±2.0 smooth muscle cells per 100 µm; P<0.05), while a significant reduction in capillary VMC density (5.1±2.3 in diabetic macular edema versus 14.9±6.0 pericytes per 100 µm in diabetes without diabetic retinopathy; P=0.01) and capillary density (superficial capillary plexus vessel density, 37.6±3.8 in diabetic macular edema versus 45.5±2.4 in diabetes without diabetic retinopathy; P<0.0001) is associated with more advanced stages of clinical DR, particularly diabetic macular edema. Our results offer a new framework for understanding the pathophysiologic course of VMC compromise in DR, which may facilitate the development and monitoring of therapeutic strategies aimed at VMC preservation and potentially the prevention of clinical DR and its associated morbidity. Imaging retinal VMCs provides an unparalleled opportunity to visualize these cells in vivo and may have wider implications in a range of diseases where these cells are disrupted.

Oxidative stress and optical coherence tomography angiography evaluation of choriocapillaris and retinal vessel density in children with obstructive sleep apnea.

To investigate the vascular networks of the retina and choroid using optical coherence tomography angiography (OCTA) to identify early biomarkers of obstructive sleep apnea (OSA) severity and to evaluate correlations with blood levels of oxidative stress. Patients with OSA were diagnosed based on video-polysomnography (PSG) and blood samples were collected to evaluate oxidative stress markers: total antioxidant status (TAS), biological antioxidant potential (BAP) test, Diacron reactive oxygen metabolites (d-ROMs) test. The eyes of children with OSA were evaluated and compared with eyes of healthy age-matched children. OCTA imaging was carried out to evaluate the choroidal and retinal vascular network density indices. A total of 31 children with OSA were recruited and compared with 10 healthy children. Choriocapillaris flow area decreased (p = 0.006) and superficial capillary plexus vessel density increased (p=0.01) with increasing severity of OSA. Children with OSA showed significant differences in TAS and d-ROMs test when compared to normal pediatric values (p<0.05). In calculating the correlations between PSG, oxidative stress, and OCTA variables, there was a negative correlation between choriocapillaris flow area and apnea hypopnea index (AHI) (p = 0.02, r2 -0.5) and between choriocapillaris flow area and the d-ROMs test (p 0.03; r2 0.5). The severity of OSA was associated with the choroidal and retinal capillary vascular networks. The correlation of the choriocapillaris flow area with AHI and the d-ROMs test indicates the connection of the choroidal microvasculature with the number of obstructive apnea and hypopnea events and oxidative stress.

Effect of perfluoropropane (C3F8) versus sulfurhexafluoride (SF6) tamponades on the retinal microvasculature after macular hole surgery

PurposeTo determine the effects of C3F8 and SF6 gasses by using optical coherence tomography angiography (OCTA) in patients with surgically closed idiopathic full-thickness macular holes (FTMH). MethodsA prospective, comparative study, in which 38 eyes of 38 patients with an idiopathic FTMH were studied. Twenty patients were randomized to the C3F8 group and 18 patients to the SF6 group. All patients underwent pars plana vitrectomy, internal limiting membrane peeling with 14 % C3F8 or 20 % SF6 gasses. The superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel densities (VD), foveal avascular zone (FAZ) area in SCP, the choriocapillaris flow area; and subfoveal choroidal thickness (SFCT) were examined at preoperative and postoperative first- and third-month controls using OCTA. ResultsWhen the changes in the FAZ, SFCT, SCP and DCP VDs were compared, no significant differences were found between the groups (p>0.05 for all). It was determined that the 1-mm radius flow area increases in the C3F8 group at the first and third months after the surgery were significantly higher than in the SF6 group (p<0.05). A significant gain was observed in the BCVA values compared to their preoperative values for both groups; however any differences between the C3F8 and SF6 groups in terms of BCVA were not detected in this study. ConclusionThis is the first report to compare the effects of C3F8 and SF6 gasses on idiopathic FTMH surgery by using OCTA. C3F8 and SF6 gasses may have similar effect on the remodeling process of vascular tissues.

Quantitative evaluation of retinal and choroidal microcirculation in inactive ocular sarcoidosis.

To evaluate retinal and choroidal alterations in eyes with inactive ocular sarcoidosis and to compare the findings with healthy controls. This cross-sectional study included 11 patients with inactive ocular sarcoidosis (study group) and 11 healthy individuals (control group). Retinal and choroidal vascular differences were evaluated using optical coherence tomography angiography (OCTA) and enhanced depth imaging-optical coherence tomography (EDI-OCT). A total of 21 eyes of ocular sarcoidosis patients without active inflammation and 22 eyes of healthy controls were analyzed. The mean whole-image deep capillary plexus vessel density was significantly lower in the study group than in the control group (P = 0.03). The acircularity index values were significantly higher, and the foveal density-300 values were significantly lower in the study group than in the control group (P = 0.01, both). The flow areas of the choriocapillaris at 1-, 2-, and 3-mm radius areas were also significantly lower in the study group (all P < 0.01). The mean choroidal thickness (CT) was significantly lower in all regions between nasal and temporal at 3000 μm in the study group (all P < 0.05). The choroidal vascularity index (CVI) values were also significantly lower in the study group (P < 0.01). Ocular sarcoidosis was associated with a reduction in CT and the CVI with a decrease in retinal vessel density and choriocapillary flow parameters. The combination of OCTA and EDI-OCT imaging may be useful in monitoring ocular sarcoidosis eyes to detect alterations in the retinal and choroidal layers.

Retinal Microvascular Changes in Internal Carotid Artery Stenosis.

Purpose: We aimed to analyze retinal microvascular parameters, measured by optical coherence tomography angiography in patients with internal carotid artery stenosis compared to healthy individuals. Materials and Methods: A total of 41 eyes from 30 patients who had varying degrees of carotid stenosis, and 42 eyes from 42 healthy controls, were enrolled in this study. Depending on the degree of stenosis evaluated by Doppler ultrasonographic imaging, the patient group was further subclassified into mild, moderate, and severe carotid artery stenosis. Superficial and deep capillary plexus vessel densities, radial peripapillary capillary vessel density, foveal avascular zone, and flow densities in the choriocapillaris and outer retina were evaluated by optical coherence tomography angiography. Results: The superficial and deep capillary plexus vessel densities were significantly reduced among the groups, only sparing the foveal region. The mean superficial plexus vessel density was 45.67 ± 4.65 and 50.09 ± 4.05 for the patient and control group, respectively (p = 0.000). The mean deep capillary plexus density was 46.33% ± 7.31% and 53.27% ± 6.31% for the patient and control group, respectively (p = 0.000). The mean superficial and deep capillary vessel densities in the foveal region did not show any statistical difference between the patient and control groups (p = 0.333 for the superficial and p = 0.195 for the deep plexus vessel density). Radial peripapillary capillary vessel density was decreased in the patient group (p = 0.004). The foveal avascular zone area was wider in the patient group but this difference did not show a significant difference (p = 0.385). Conclusions: Retinal microvascular changes are a prominent outcome of internal carotid disease, and even mild stenosis can lead to alterations in the retinal microvascular bed which could be detected by OCTA. By early detection of microvascular changes in the retina in this patient group, we might speculate the overall vascular condition.

Longitudinal Assessment of Macular Thickness and Microvascular Changes in Children with Sickle Cell Disease

To longitudinally assess macular thickness and microvascular changes in children with sickle cell disease (SCD). A retrospective consecutive series. Children with SCD aged ≤ 18 years who had an ophthalmic examination at Boston Children's Hospital between January 1998 and August2022. Qualitative and quantitative analyses of both OCT and OCT angiography (OCTA) images were performed. Total retinal thickness measured on macular OCT, superficial capillary plexus and deep capillary plexus (DCP) vessel density (VD), and foveal avascular zone (FAZ) area measured on 6-× 6-mm OCTA scans. International Classification of Diseases, 10th Revision, code search identified 303 pediatric SCD patients who underwent ophthalmic examination during the study period. OCT and OCTA images were acquired on 104 (17.2%) and 60 (9.9%) eyes at presentation and on 159 (26.2%) and 100 (16.5%) eyes at final visit, respectively. Overall, temporal retinal thinning was noted qualitatively in 35.6% of SCD patients at presentation and 39.6% at final visit. Of those patients with macular thinning, 94.6% and 90.5% had peripheral sickle cell retinopathy (SCR) at presentation and final visit. On quantitative OCT analysis, HbSS eyes had a lower retinal thickness in the fovea and temporal parafovea compared with HbSC (P < 0.05). Eyes with peripheral SCR had a larger FAZ at presentation compared with eyes without peripheral SCR (P= 0.004), a lower DCP VD at final visit in the inferior temporal macula (P= 0.03), and a higher DCP VD at final visit in the superior nasal macula (P= 0.01). Eighty eyes of 40 patients had OCT, and 34 eyes of 20 patients had both OCT and OCTA images acquired at both initial and final visits. At final visit, retinal thickness decreased at the fovea, inferior perifovea, and temporal perifovea compared with presentation (P < 0.05). In parallel, VD DCP in the superonasal quadrant increased at final visit (P= 0.03). Macular retinal thinning was progressive and observed in eyes with and without peripheral SCR. Over time, there was a compensatory increase in DCP VD in the nasal macula on OCTA. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Optical Coherence Tomography Angiography Is a Useful Tool for Distinguishing Primary Raynaud's Phenomenon from Systemic Sclerosis and/or Very Early Disease of Systemic Sclerosis.

This cross-sectional study aimed to compare optical coherence tomography angiography (OCT-A) findings in patients with primary Raynaud's phenomenon (PRP; n = 22), very early disease of systemic sclerosis (VEDOSS; n = 19), and systemic sclerosis (SSc; 25 patients with limited cutaneous SSc (lcSSc) and 13 patients with diffuse cutaneous SSc (dcSSc)). Whole, parafoveal, and perifoveal superficial capillary plexus (SCP) vessel densities (VDs), deep capillary plexus VDs, and whole, inside, and peripapillary VDs were significantly higher in the PRP group (p < 0.001). In the lcSSc group, the FAZ perimeter was significantly higher than that in the VEDOSS group (p = 0.017). Retinal nerve fiber layer VDs were significantly lower in the lcSSc group than in the PRP and VEDOSS groups (p < 0.001). The whole and peripapillary optic disc VDs of the VEDOSS group were significantly higher than in the lcSSc group (p < 0.001). Whole SCP VDs (94.74% sensitivity, 100.00% specificity) and parafoveal SCP VDs (89.47% sensitivity, 100.00% specificity) showed the best performance in distinguishing patients with SSc from those with PRP. OCT-A seems to have potential diagnostic value in differentiating patients with PRP from patients with SSc and VEDOSS, and there is potential value in assessing prognostic roles, since findings from OCT-A images could be early indicators of retinal vascular injury long before overt SSc symptoms develop.

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.

Optical coherence tomography angiography characteristics of retinochoroidal and optic nerve head microcirculation in cryptogenic organizing pneumonia

BackgroundTo assess retinochoroidal and optic nerve head microcirculation alterations in cryptogenic organizing pneumonia. MethodsThirty cryptogenic organizing pneumonia patients in the resolution phase (group 1, 30 right eyes) and 33 healthy subjects (group 2, 33 right eyes) were compared. Patients had 40 mg/day corticosteroids for 8–10 days, and a pulmonary function test, which revealed only minimally restrictive ventilation features. After gathering demographic data, a comprehensive ophthalmological exam and optical coherence tomography angiography were performed three months following maximum disease resolution with corticosteroid therapy ResultsGroups 1 and 2 had mean ages of 54.37±14.87 and 49.61±12.36 years, respectively (P = 0.171). Despite the lack of statistical significance, superficial and deep capillary plexus vessel densities in all macular regions were lower in group 1, as were foveal avascular zone parameters (P>0.05). However, the outer retinal and choriocapillaris flows increased significantly in group 1, especially in select areas (P<0.001, for both). There were no significant differences in whole image (P = 0.346), inside disk (P = 0.438), or peripapillary (P = 0.185) optic nerve head vessel densities between the two groups; however, nasal (P<0.001) and inferior quadrant (P = 0.006) vessel densities differed significantly. Global retinal nerve fiber layer thickness did not differ significantly between groups 1 and 2 (112.83±14.71 versus 111.45±12.74 µm, respectively; P = 0.692). Group 1, however, had significantly higher superior, nasal, and inferior quadrant, and significantly lower temporal quadrant retinal nerve fiber layer thickness (P<0.001, for all). ConclusionsConcerning the impact of probable cryptogenic organizing pneumonia-induced hypoxia on ocular tissues, optical coherence tomography angiography assessments of retinochoroidal and optic nerve head microcirculation could be employed as a biomarker for cerebral microcirculation.

Multimodal imaging features of acute macular retinopathy in patients with COVID-19

Objective: To investigate the multimodal imaging characteristics of acute macular retinopathy (AMR) and/or parafoveal acute middle maculopathy (PAMM) in patients with coronavirus disease 2019 (COVID-19). Methods: It was a cross-sectional study. Eight patients (15 eyes) diagnosed with AMN and/or PAMM, who presented for their initial visit at Kaifeng Eye Hospital between December 17 and December 31, 2022 and were also confirmed positive for COVID-19, were enrolled as the observation group. The patients were classified into four types based on swept-source optical coherence tomography (SS-OCT) findings. Fifteen healthy volunteers (15 eyes) without ocular or systemic diseases were recruited as the healthy control group, and one eye was randomly selected for analysis. All participants underwent detailed ophthalmic examinations, including best-corrected visual acuity (BCVA), slit-lamp biomicroscopy, fundus photography (FP), intraocular pressure measurement, fundus infrared imaging, OCT and OCT angiography (OCTA). The foveal avascular zone (FAZ) area of the macular center was measured. General information and multimodal imaging findings were collected and analyzed. The superficial capillary plexus vessel density (SCP-VD) and deep capillary plexus vessel density (DCP-VD) were measured in circular areas with diameters of 1.0 mm, >1.0 mm and ≤3.0 mm, and>3.0 mm and ≤6.0 mm centered on the foveal center, recorded as SCP-VD1.0, 3.0, 6.0 and DCP-VD1.0, 3.0, 6.0. Statistical analyses were performed using t-tests, Mann-Whitney U tests, and chi-square tests. Results: The observation group consisted of 6 males (11 eyes) and 2 females (4 eyes) with a mean age of (26.87±11.56) years. The healthy control group included 11 males (11 eyes) and 4 females (4 eyes) with a mean age of (28.75±12.30) years. There were no statistically significant differences in age and gender distribution between the two groups (all P>0.05). All patients in the observation group experienced high fever (≥39.0 ℃) and developed ocular symptoms during the febrile period or within 24 hours after fever resolution. Among all patients, there were 5 cases (7 eyes) of Type Ⅰ, 1 case (1 eye) of Type Ⅱ, 3 cases (4 eyes) of Type Ⅲ, and 2 cases (3 eyes) of Type Ⅳ. In Type Ⅲ and Ⅳ, 3 cases (4 eyes) exhibited weakly reflective cystic spaces in the outer plexiform or outer nuclear layers, and fundus photography revealed multiple gray or reddish-brown lesions in the macular region. One case (1 eye) showed retinal superficial hemorrhage. Cotton wool spots were observed in 2 cases (4 eyes). Fundus infrared imaging showed that Type Ⅰ manifested as weak reflectivity lesions in the parafoveal central zone, with the tip pointing towards the fovea. Type Ⅱ showed no apparent abnormalities in the macular region, while Type Ⅲ and Ⅳ displayed map-like weak reflective lesions spanning the foveal center. OCTA findings demonstrated that SCP-VD1.0 in the observation group was 6.93% (4.77%, 6.93%), significantly lower than the healthy control group's 10.66% (8.05%, 10.55%) (U=174.00, P=0.016). SCP-VD3.0 in the observation group was 37.14% (32.15%, 43.48%), also lower than the healthy control group's 43.06% (38.95%, 46.55%) (U=174.00, P=0.016). DCP-VD3.0 in the observation group was 48.20% (46.11%, 50.33%), lower than the healthy control group's 51.10% (50.04%, 53.02%) (U=188.00, P=0.009). DCP-VD6.0 in the observation group was 49.27% (47.26%, 51.67%), lower than the healthy control group's 52.43% (50.07%, 53.82%) (U=70.00, P=0.004). There were no significant differences in SCP-VD6.0 and DCP-VD1.0 between the two groups (both P>0.05). Conclusions: Acute macular retinopathy in patients with COVID-19 can involve all retinal layers and present as segmental hyper-reflectivity on SS-OCT. Fundus infrared imaging reveals weak reflectivity in the affected area, fundus photography shows multiple gray or reddish-brown lesions in the macular region, and OCTA demonstrates a decrease in SCP-VD and DCP-VD.

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