Optical Coherence Tomography Angiography Research Articles

Effect of reduced saturation and elevated D-dimer and interleukin 6 levels on vessel density and foveal avascular zone in patients with COVID-19 bilateral pneumonia.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can affect multiple organs, including the eyes. This study aimed to identify associations between vascular density (VD) and the foveal avascular zone (FAZ), assessed using optical coherence tomography angiography (OCTA), and baseline levels of D-dimers and interleukin 6 (IL-6) in patients with bilateral COVID-19 pneumonia, depending on oxygen saturation (SpO2) on admission. The study included patients with COVID-19 bilateral pneumonia due to SARS-CoV-2 infection who were hospitalized between March and May 2021. Ophthalmological examination was performed 2 months after hospitalization. Optical coherence tomography angiography was used for the automatic assessment of the central retinal VD and the manual assessment of FAZ. A significant monotonic negative relationship was observed between SpO2 . 90% and VD in some areas of the superficial capillary plexus (SCP) (p = 0.048) and choriocapillaris (p = 0.021), and the mean VD in the deep capillary plexus (DCP) (p = 0.048). No significant monotonic negative relationship was noted between SpO2 . 90% and the FAZ in the SCP (p = 0.075). However, there was a significant monotonic positive relationship between VD in the nasal choriocapillaris and D-dimer levels in patients with SpO2 . 90% (p = 0.003, respectively). Finally, a monotonic negative relationship was identified between foveal VD in the DCP and IL-6 levels in patients with SpO2 . 90% (p = 0.027). An OCTA study conducted 2 months after hospitalization for COVID-19 bilateral pneumonia showed reduced VD in those with SpO2 . 90% and elevated levels of D-dimers and IL-6 during hospitalization. Optical coherence tomography angiography testing can provide monitoring of ocular status in patients following SARS-CoV-2 infection, especially those who report visual disturbances.

Evaluation of retinal and choroidal microvascular alteration after ICL V4c implantation based on OCTA.

To evaluate the changes of retinal and choroidal microvascular including the superficial retinal capillary plexus (SCP), deep retinal capillary plexus (DCP), choriocapillaris (CC), and central retinal thickness (CRT) in high myopic eyes after the implantable collamer lens with a central hole (ICL V4c) implantation using optical coherence tomography angiography (OCTA). This retrospective study included 30 eyes of 30 patients (14 males and 16 females) who underwent ICL V4c implantation in Tianjin Aier Eye Hospital from October 2022 to May 2023. Uncorrected distant visual acuity (UDVA), best corrected distance visual acuity (BDVA), intraocular pressure (IOP), spherical equivalent (SE), axial length (AL), and optical coherence tomography angiography (OCTA) were measured and assessed before surgery, and 1 week, 1 month, and 3 months after surgery. OCTA was used to image and measure several key indicators: the foveal avascular zone (FAZ), vascular density (VD) of the SCP and DCP, blood flow density (BD) of the CC, and CRT. All measurement data were obtained utilizing the instrument's proprietary software, ensuring accuracy and consistency. UDVA were significant improvements at the 1 week, 1 month, and 3 months after ICL V4c implantation surgery. BDVA, FAZ, and CRT maintained stable, however, IOP was higher at 1 week and 3 months post-operation compared to 1-month post-operation. The statistically significant difference was identified within the S3, S7, and S9 of SCP at each time point before and after the surgery (P1 = 0.004; P2 = 0.014; P3 = 0.037). However, paired analyses showed that there was a significant decrease in VD of S3 at 1 week after ICL V4c implantation surgery (P<0.05), which then returned to preoperative levels by 1 month (P>0.05), and the increase in VD of the S7 region at 1 month after ICL V4c implantation, which is significant compared to 1 week post-surgery, but not compared to preoperative levels. An overall comparison of the BD of the CC (2mm) at each time point showed a statistically significant difference (P = 0.029). ICL V4c implantation offers a safe and efficient therapy to the high myopic patients. However, the retinal and choroidal microvascular changes need to be paid attention to in post-ICL implantation patients.

112° field of view high-resolution swept-source OCT angiography for rat retinas

This study introduces an ultra-wide field (UWF) and high-resolution swept-source optical coherence tomographic angiography (OCTA) system for rat retinal imaging. Using an asymmetrical optics design, the system achieves unprecedented details of retinal structures and vascular plexuses over a large field of view (112°) in a single-shot acquisition. Views of single-nerve fiber bundles and single capillary vessels are consistently visible over a 112° field of view. The system has a long imaging range and high penetration and allows a full view of vitreous hyaloid vessels, retina, choroid, sclera, and posterior ciliary arteries, down to sub-sclera connective tissues. In a longitudinal study of oxygen-induced retinopathy (OIR) in rats, the system successfully revealed the progression and regression of OIR-related vascular pathologies, such as ischemia, neovascularization, and tortuosity. To our knowledge, this novel UWF-OCT/OCTA prototype designed for rat retinal imaging will be a vital tool for monitoring disease progression and evaluating therapeutic interventions in preclinical models.

Barriers in Healthcare to the Use of Optical Coherence Tomography Angiography in Multiple Sclerosis.

Optical coherence tomography angiography (OCT-A) is a state-of-the-art imaging technique for the retinal vasculature to accurately segment the capillary network and assign it to retinal layers. OCT-A is a promising technique to better understand neurological diseases with visual system manifestations, such as multiple sclerosis (MS), and to identify and characterize vascular biomarkers. Initial studies suggested vascular changes in MS and its differential diagnoses such as myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and neuromyelitis optica spectrum disorder (NMOSD). Here we review clinical and technical aspects of OCT-A imaging and discuss the potential for the MS field as well as barriers that need to be overcome before OCT-A can be established in clinical application.

Safety of and chorioretinal circulation during repeated low-level red-light therapy for myopic children.

To evaluate the safety of repeated low-level red-light (RLRL) therapy in children, and the dynamic evolution of choroidal and retinal blood flow. This is a single-centre, randomised, single-blind, parallel-group clinical trial. Seventy myopic children were randomly assigned to either the intervention group [receiving RLRL therapy plus single-vision spectacle (SVS)] or the control group (wearing SVS). Participants underwent comprehensive ophthalmic examinations following their first irradiation, 9 months continuous RLRL therapy and stop of treatment. Quantitative analyses of choroidal and retinal microcirculation were analysed via optical coherence tomography angiography. Over 9 months of treatment, while the RLRL treatment demonstrated significantly less increases in refractive error and axial length compared with the SVS treatment (ps < 0.05), no abnormalities in fundus structure or visual function (mfERG, VEP and microperimetry) were detected (ps > 0.05). A single red-light exposure did not exert a significant influence on choroidal thickness (ps > 0.05). Upon continuous treatment, the RLRL group achieved peak values in these circulations at 9 months (ps < 0.05). Following cessation of exposure, all circulations exhibited a declining trend, reaching similar levels in both groups (ps > 0.05). As the frequency of red-light exposures intensified, there was a consistent surge in these circulations (ps < 0.05). Nine months of continuous RLRL exposure does not cause toxic side effects on retinal or optic nerve functions, and there is a time-dependent cumulative response in choroidal and retinal circulation.

Analysis of retinal and choroidal microvasculature in systemic sclerosis using optical coherence tomography angiography: A systematic review and meta-analysis.

Optical coherence tomography angiography (OCTA) is an emerging technique to investigate retinal and choroidal microvascular alterations in patients with systemic sclerosis (SSc). This systematic review and meta-analysis aimed to evaluate the features of retinal and choroidal microvasculature using OCTA among SSc patients. The methodology of the study was based on PRISMA guidelines. PubMed, Scopus, Web of Science, and Embase were searched systematically on November 25, 2023, for relevant studies utilizing OCTA as the main diagnostic tool to assess the retinal and choroidal microvasculature in SSc patients versus healthy controls. Random-effect or fixed model meta-analysis was used based on the heterogeneity of studies. Eleven observational comparative studies, including 366 patients with SSc and 350 healthy controls, conducted between 2020 and 2023, were included in this review. Meta-analysis findings revealed a significant decrease in vessel densities in both the superficial and deep capillary plexuses (SCP and DCP) among SSc patients compared to controls. However, there were no significant differences observed in the foveal avascular zone (FAZ) area and choriocapillary flow area (CCFA) between SSc patients and controls. Moreover, central macular thickness (CMT) consistently exhibited a decrease in SSc patients, while retinal nerve fiber layer (RNFL) thickness showed no significant differences. Although radial peripapillary capillary (RPC) vessel density, subfoveal choroidal thickness (CMT), and cup/disc ratio yielded mixed results, with some studies indicating significant changes in the SSc group, meta-analysis could not be performed due to variations in the OCTA machines used across the included studies. This systematic review demonstrates retinal and choroidal microvascular abnormalities in SSc using OCTA. Longitudinal studies are needed to understand how these abnormalities evolve over time in patients with SSc and whether these abnormalities correlate with the clinical features of SSc.

Early Choriocapillaris Dysfunction in Fellow Eyes of Patients with Unilateral Neovascular Age-Related Macular Degeneration.

To investigate early changes in AMD by evaluating and comparing choriocapillaris (CC) flow in fellow eyes of patients with unilateral neovascular age-related macular degeneration (nAMD) and in healthy controls using swept-source optical coherence tomography angiography (SS-OCTA). Patients with unilateral nAMD and no/early/intermediate AMD (no/e/iAMD) in their fellow eye and normal controls who underwent SS-OCT and OCTA where included. CC perfusion was assessed on MATLAB as percentage of flow deficits (FD%) in the central 4.5 × 4.5 mm macular region, after removing artifacts. 81 eyes/patients (22 eyes with noAMD, 30 with eAMD, 29 with iAMD) with unilateral nAMD and 24 controls were analyzed. Median FD% was 8.97 (IQR 8.58-9.53) in AMD group, 8.92 (IQR 8.64-9.27) in noAMD group, 8.96 (IQR 8.46-9.38) in eAMD group, 9.05 (IQR 8.58-9.8) in iAMD group, and 8.22 (IQR 7.78-8.55) in controls. A statistically significant difference in FD% was observed between controls and AMD group (p < 0.001), as well as between each AMD subgroup and controls (noAMD vs controls p = 0.0037; eAMD vs control p = 0.0012; iAMD vs controls p = 0.0002). This study suggests that CC dysfunction may occur in fellow eyes of patients with unilateral nAMD before visible AMD signs, potentially preceding RPE changes. Further longitudinal studies are needed to confirm these findings and explore the correlation with AMD development/progression.

Midperipheral Microvascular Defects and Their Associations With Vitreoretinal Abnormalities in Early-Stage Familial Exudative Vitreoretinopathy.

To investigate microvascular growth defects in the temporal midperipheral retina and their correlations with vitreoretinal microstructural abnormalities (VRMAs) in early-stage familial exudative vitreoretinopathy (FEVR). We enrolled 127 patients (127 eyes) with early-stage FEVR and 31 healthy subjects (31 eyes). Widefield optical coherence tomography angiography was conducted for all enrolled eyes. Vessel density (VD), vessel diameter index (VDI), and vessel index (VI; VD/VDI) of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) in temporal midperiphery were further evaluated. The distance from the vessel sprouting point of the optic disc to the avascular area margin (Optic-AVA) was measured to assess retinal vascular dysplasia. In early-stage FEVR, 61.42% of eyes showed retinal microvascular abnormalities (MVAs) in the temporal midperiphery, all combined with VRMAs. Common MVAs presented disordered vascular anastomoses in the SCP and capillary loss in the DCP, corresponding to deficient neuroretina. The preretinal vasculature (PRV) was detected in 36 eyes. VD and VI were lower in FEVR eyes compared to controls, whereas the VDI in the SCP was larger (all P < 0.001). Optic-AVA was positively correlated with VD and VI in both plexuses and negatively correlated with the VDI in the SCP. PRV existence was independently correlated with decreased VI in the DCP (odds ratio [OR] = 0.322; P < 0.001), and VRMA existence was independently correlated with decreased VI in SCP and DCP (SCP OR = 0.282, P = 0.010; DCP OR = 0.562, P = 0.002). MVAs in the temporal midperipheral retina were revealed. Microvascular loss may be correlated with Optic-AVA reduction, PRV, and the presence of VRMAs.

Retinal microvascular phenotypes can track small vessel disease burden and CPAP treatment effectiveness in obstructive sleep apnoea.

Optical coherence tomography angiography (OCT-A) retinal imaging enables in vivo visualization of the retinal microvasculature that is developmentally related to the brain and can offer insight on cerebrovascular health. We investigated retinal phenotypes and neuroimaging markers of small vessel disease (SVD) in individuals with obstructive sleep apnoea (OSA). We enrolled 44 participants (mean age 50.1 ± SD 9.1 years) and performed OCT-A imaging before and after continuous positive airway pressure (CPAP) therapy. Pre-treatment analyses using a generalized estimating equations model adjusted for relevant covariates, revealed perivascular spaces (PVS) volume in basal ganglia associated with greater foveal vessel density (fVD) (p-value < 0.001), and smaller foveal avascular zone area (p-value = 0.01), whereas PVS count in centrum semiovale associated with lower retinal vessel radius (p-value = 0.02) and higher vessel tortuosity (p-value = 0.01). A reduction in retinal vessel radius was also observed with increased OSA severity (p-value = 0.05). Post-treatment analyses showed greater CPAP usage was associated with a decrease in fVD (p-value = 0.02), and increased retinal vessel radius (p-value = 0.01). The findings demonstrate for the first time the potential use of OCT-A to monitor CPAP treatment and its possible impact on both retinal and brain vascular health.

In vivo assessment of cone loss and macular perfusion in children with myopia

This study evaluated cone density (CD) in the macular region and assess macular perfusion in children with varying degrees of myopia. This was a prospective, cross-sectional, observational study. Children underwent confocal scanning laser ophthalmoscopy (cSLO), optical coherence tomography (OCT), and OCT angiography (OCTA) imaging. A built-in software was used to measure mean CD (cells/mm2), retinal vessel density, choriocapillaris perfusion area, and choroidal thickness (CT). The study included 140 eyes from children categorized into four groups: emmetropia (31 eyes), low myopia (44 eyes), moderate myopia (31 eyes), and high myopia (34 eyes). The high myopia group exhibited significantly lower macular CD than the emmetropia group (P < 0.05). Additionally, the high myopia group showed thinner CT and higher choriocapillaris perfusion area in the macular region than the emmetropia group (all P < 0.01). Macular CD was significantly correlated with age, spherical equivalent, axial length, and CT (all P < 0.05). Generalized linear models revealed CT as the independent factor associated with macular CD (Wald χ2 = 9.265, P = 0.002). Children with high myopia demonstrate reduced CD in the macular region, accompanied by reduced CT. These findings may have important implications for future myopia prevention and management strategies.

Exploring retinal vessel density alterations in prolactinoma patients: Insights from OCTA imaging.

To investigate microvascular changes in the macular and peripapillary area in prolactinoma patients by using optical coherence tomography angiography (OCTA). A retrospective study. This study included 40 patients with treatment-naive prolactinoma and 42 healthy controls. Participants underwent comprehensive ophthalmic examinations, visual field testing, and optical coherence tomography (OCT) assessments, including retinal nerve fiber layer (RNFL) thickness, macular, and peripapillary region OCTA by using the Topcon DRI OCT Triton Swept Source-OCT system. The OCTA results were evaluated between groups and then correlated with PRL levels. The differences in best-corrected visual acuities were statistically significant among the groups. The RNFL thickness in the superior and nasal quadrants was significantly lower in the prolactinoma group. The prolactinoma group showed significant reductions in macular vessel density (VD) across all layers than the control group, except in the deep retinal capillary plexus temporal quadrants. The radial peripapillary capillary (RPC) temporal VD in the prolactinoma group was significantly lower. In patients with optic neuropathy, correlations were observed between the RPC temporal and RNFL temporal sectors (r = 0.650, P = 0.03), and between the RPC inferior and RNFL inferior sectors (r = -0.612, P = 0.045). Between PRL levels and OCTA parameters, negative correlations were observed (RPC inferior: r = -0.452, P = 0.003; DCP superior: r = -0.379, P = 0.016). Our study revealed reduced VD in the macula and RPC temporal regions in patients with treatment-naive prolactinoma. OCTA holds significant importance in detecting potential retinopathies and vasculopathies. Future research should focus on examining pre- and post-treatment changes in treatment-naive patients without ON to better understand the impact of prolactinoma.

Ocular manifestations of West Nile virus.

Over the past two decades, the ophthalmic manifestations of West Nile virus have been more clearly established in the literature. This review aims to summarize its diagnosis and pathogenesis, with a focus on its clinical appearance, characteristic imaging features, and management. Ocular manifestations of West Nile virus present early in the disease course and are more common in cases with severe neurological involvement. The use of optical coherence tomography (OCT), optical coherence tomography angiography (OCT-A), fundus autofluorescence (FAF), fluorescein angiogram (FA), and indocyanine green angiography (ICGA) can aid in its diagnosis and management. West Nile virus infection may present with ocular findings that include anterior uveitis, vitritis, retinitis, chorioretinitis, and optic neuropathy; visual prognosis can range from excellent to poor depending on severity of involvement and the presence of secondary complications, such as occlusive vasculitis and macular ischemia. Diagnosis may be aided by multimodal imaging assessment. The ophthalmologist should have a high clinical suspicion for ocular involvement in cases of severe systemic disease.

The effects of topical latanoprost 0.005% treatment on microvascular changes in the optic nerve head and macula.

This prospective study aimed to assess the impact of topical latanoprost 0.005% treatment on the microvasculature of the macula and optic nerve head (ONH) in primary open-angle glaucoma (POAG). Fifty-seven eyes of 31 subjects were enrolled. ONH whole-image (wiVD), peripapillary (ppVD), and macular vascular density (VD) parameters were measured using optical coherence tomography angiography before treatment, at the 1st month, and at the 3rd month of treatment. There was a significant reduction in IOP post treatment, with a decrease of 17.0 ± 2.3 mmHg in the 1st month and 16.3 ± 2.5 mmHg in the 3rd month (P < 0.001 for both). ONH wiVD and ppVD significantly increased at the post-treatment 1st month (P = 0.001 for both) but decreased by the 3rd month, returning to baseline levels (P < 0.001 for both), indicating a return to pre-treatment levels (P > 0.05 for both). Similarly, macular wiVD and perifoveolar VD (pefVD) increased significantly at the 1st month (P = 0.013 and P < 0.001, respectively) but returned to baseline by the 3rd month (P < 0.001 for both). No significant difference was observed between before-treatment and post-treatment 3rd month regarding the macular wiVD and pefVD (P > 0.05 for both). Deep capillary plexus and foveal avascular zone parameters did not change during follow-up (P > 0.05 for both). The initial increase in ONH and peripapillary VD, as well as macular VD, is attributed to the acute reduction in IOP from topical latanoprost 0.005%. However, the diminishment of sustained differences by the 3rd month indicates adaptation of the ONH and retinal microvasculature to decreased IOP through compensatory mechanisms.

Morphometrics of polypoidal choroidal vasculopathy lesions and choroidal vascular associated with treatment response using swept-source optical coherence tomography angiography

PurposeTo evaluate quantitative metrics of neovascularization lesions and choroidal vascular using swept-source optical coherence tomography angiography (SS-OCTA) in polypoidal choroidal vasculopathy (PCV) eyes, and investigate the relationship between imaging biomarkers and treatment outcomes of intravitreal anti-vascular endothelial growth factor (VEGF). MethodsWe retrospectively recruited 56 PCV patients. Choroidal features included subfoveal choroidal thickness (SFCT) and choroidal vascularity index (CVI). Quantitative metrics of neovascularization lesions included total vessel length (TVL), average vessel length (AVL), junction density (JD), total number of endpoints (TNE), and mean lacunarity (ML). We performed multivariate logistic and linear regression models to determine the prognostic factors for functional and morphological outcomes. ResultsBy comparison, functional good-responders had poorer best corrected visual acuity, higher TNE, and lower ML at baseline. Morphological good-responders had higher central retinal thickness, higher TNE, lower TVL and AVL, lower ML, lower SFCT and CVI. High-shrinkage of vessel area subgroup had higher JD and TNE, lower TVL and AVL, lower ML, lower SFCT and CVI. Multivariate analysis showed good morphological response was correlated with lower SFCT (P < 0.01). High-shrinkage subgroup was correlated with lower AVL (P = 0.017) and higher TNE (P < 0.01). ConclusionQuantitative metrics of neovascularization lesions and choroidal characteristics using SS-OCTA had the potential to be imaging biomarkers for predicting the response to anti-VEGF treatment. PCV lesions with higher TNE and lower AVL tended to appear higher shrinkage of vessel area, and lower SFCT was correlated with good morphological response.

Peripapillary vessels density is closely related to cerebral white matter hyperintensities: An OCTA study.

Chronic cerebral hypoperfusion triggers the development of white matter hyperintensities (WMHs), common in cerebral small vessel disease (CSVD). However, conventional imaging techniques cannot visualize cerebral small vessels. The retina, a direct extension of the central nervous system, has an unclear correlation with WMHs. This study employs Optical coherence tomographic angiography (OCTA) to investigate vascular changes in the retina and explore its correlation with WMHs, aiming to provide a new method for assessing perfusion in early ischemic brain WMHs. Forty-nine patients with WMHs were stratified into mild and moderate/severe WMHs groups based on MRI findings, utilizing the Fazekas and Scheltens scales. OCTA assessed fundus vessel microcirculation. Logistic regression analyzed the correlation between ocular fundus microcirculation and WMH severity and location. Additionally, ROC curves evaluated the diagnostic efficacy of each fundus vascular microcirculation index in determining WMH severity. After adjusting for multiple confounders, finding consistently indicated that the moderate/ severe WMHs group exhibited lower vessel density (VD) in the superior quadrant of the inner peripapillary region compared to the mild group [OR = 0.487, CI (0.255,0.929), p < 0.05]. ROC curves revealed that when combined with age, diabetes, and superior quadrant VD of the inner peripapillary region, specificity could be increased to 94.1%. Peripapillary vessel density correlates closely with the severity of cerebral WMHs. Early morphological changes due to chronic hypoperfusion may initiate from the inner layer of the optic disc, and OCTA could offer a novel method for evaluating blood perfusion in ischemic WMHs.

Assessing Preclinical Diabetic Retinopathy: The Role of Optical Coherence Tomography Angiography

Assessing Preclinical Diabetic Retinopathy: The Role of Optical Coherence Tomography Angiography

Optical Coherence Tomography Angiography in Macular Neovascularization Secondary to Focal Choroidal Excavation

Purpose: To highlight the use of multimodal imaging for detecting and monitoring macular neovascularization (MNV) in the presence of focal choroidal excavation. Methods: A case and its findings were analyzed. Results: Spectral-domain optical coherence tomography (OCT) and OCT angiography (OCTA) were performed in a 30-year-old Asian woman with metamorphopsia in the left eye. Imaging showed striking MNV secondary to focal choroidal excavation, and an impressive response to antivascular endothelial growth factor therapy was seen throughout the follow-up. Conclusions: OCTA is a noninvasive, useful imaging modality for diagnosing and monitoring patients with MNV secondary to focal choroidal excavation.

Association of Peripapillary Arterial Circle of Zinn-Haller with Glaucoma in Highly Myopic Eyes.

The visualization of circle of Zinn-Haller (CZH) on optical coherence tomography angiography (OCTA) or its pattern does not have a clear effect on glaucoma, while the location of CZH is associated with axial length in highly myopic eyes. To investigate the association between the CZH and the presence of glaucoma using swept-source optical coherence tomography angiography (SS-OCTA) images of the optic nerve of patients with high myopia (HM). This retrospective case series included 227 eyes with HM, comprising 134 and 93 eyes with and without glaucoma, respectively. The characteristics of CZH, including visualization, pattern, and location, were assessed using SS-OCTA. Vascular parameters, such as vessel density and microvascular dropout (MvD), were quantified. The factors affecting the presence of glaucoma and the correlations between the CZH distance and axial length (AXL) were identified using logistic regression analysis and Pearson correlation analysis, respectively. CZH was detected more frequently in HM patients with glaucoma (71.6%) than in patients without glaucoma (51.6%) (P<0.002). However, the visualization of CZH was not related to the presence of glaucoma in multivariate regression analysis (odds ratio [OR], 0.688; 95% confidence interval [CI], 0.328-1.444; P=0.322). Moreover, compared to the annular pattern used as a reference, triangular and irregular patterns were not associated with the presence of glaucoma (OR: 1.043, 95% CI: 0.101-10.763, P=0.971; OR: 0.527, 95% CI: 0.255-1.092, P=0.085, respectively). MvD was significantly higher in patients with glaucoma (61.2%) than that in patients without glaucoma (2.2%) (P<0.001) and was identified as a significant factor affecting the presence of glaucoma (OR, 42.120; 95% CI, 9.416-188.413; P<0.001). AXL showed a significant correlation with CZH distance in all patients (R=0.399; P<0.001). CZH was more commonly detected in HM patients with glaucoma. However, no clear associations of glaucoma with the visualization, pattern, or location of CZH were observed in the present study. The correlation between AXL and CZH distance in eyes with HM warrants further investigation. These results may offer insights into the pathogenesis of glaucoma in eyes with HM as OCTA technology advances.

Optical coherence tomography angiography of peripapillary vessel density in non-arteritic anterior ischemic optic neuropathy and demyelinating optic neuritis

BackgroundIn cases of optic disc edema or a pale optic disc, distinguishing an episode of optic neuritis (ON) from that of non-arteritic anterior ischemic optic neuropathy (NAION) during a clinical examination is challenging. Optical coherence tomography angiography (OCTA) can reveal differences in peripapillary vascular network structures and provide biomarkers for differential diagnosis.MethodsA total of 23 eyes with NAION, 22 eyes with demyelinating ON (DON), and 27 eyes from healthy participants were imaged using OCTA to observe the radial peripapillary capillaries (RPCs). Optical coherence tomography was used to measure peripapillary retinal nerve fiber layer (RNFL) thickness and the macular ganglion cell complex (mGCC). Data for all patients were recorded at 2–3 weeks and more than 3 months after the symptom onset.ResultsA total of 23 affected eyes from 23 patients with NAION (average age 52.17 ± 7.92 years), 22 eyes from 22 patients with demyelinating optic neuritis (DON) (average age 47.88 ± 19.24 years), and 27 eyes from 27 healthy individuals (average age 46.43 ± 14.08 years) were included in the study. There were no significant differences in sex, age, and eye laterality between any two groups (F = 0.968, 0.475, 0.870; p &amp;gt; 0.05). Throughout the course of NAION and DON, the superior RPC, superior mGCC, and peripapillary RNFL decreased with time (p &amp;lt; 0.05). In contrast, the inferotemporal RPC and inferior mGCC did not decrease from the acute to chronic stage in NAION (t = 1.639, 0.834, p = 0.117, 0.413). Compared with the normal group, patients with NAION and DON exhibited a sharp reduction in the average RPC, RNFL, and GCC from the acute to the chronic stage (p &amp;lt; 0.05). Patients with DON exhibited a significant decrease in the inferotemporal RPC and inferior mGCC compared with the patients with NAION (p &amp;lt; 0.05). In contrast, there were no significant differences in the inferior mGCC at the chronic stage between the patients with NAION and those with ON (t = 2.547, p = 0.093).ConclusionVarious structural and microvascular changes were observed in patients with NAION and ON, indicating distinct features of the optic nerve during the different stages of NAION and ON. Peripapillary vascular density, measured using spectral domain OCT (SD-OCT), may be a biomarker to distinguish NAION from ON.

Longitudinal OCTA vessel density loss in macula and optic nerve head in healthy, glaucoma suspect and established glaucoma eyes.

To examine longitudinal optical coherence tomography angiography (OCTA) changes in macula and optic nerve head (ONH) in healthy, glaucoma suspect (GS) and primary open-angle glaucoma (POAG) eyes. Healthy, GS and POAG eyes from Diagnostic Innovations in Glaucoma Study with ≥2 years follow-up and four visits of macular/ONH OCTA imaging were included. Rates of macular wiVD (whole-image vessel density) and ONH wiCD (whole-image capillary density) changes were calculated for each diagnosis group using join mixed-effect modelling. Differences in wiVD/wiCD change rates across diagnoses were examined through pairwise comparison. Relationships of baseline 24-2 visual field (VF) mean deviation (MD) with wiVD/wiCD change rates were evaluated for POAG eyes. There were 36, 57 and 79 eyes (25, 38 and 50 subjects) in healthy, GS and POAG groups, respectively. Rates of wiVD (range:-0.72 to -0.92 %/year) and wiCD (range:-0.28 to -0.66 %/year) loss were different from zero in all groups (p<0.05). The rates of wiCD loss differed across all diagnosis groups (p<0.001), while wiVD change rates did not increase when comparing healthy to GS eyes (p=0.167). Baseline VF MD showed a significant but modest correlation with the rates of both wiVD and wiCD loss (p<0.05), and the correlation with wiCD change rate was slightly stronger (R2=0.27 vs 0.16). In glaucoma, there is earlier microvasculature loss in the ONH than in the macula. Moreover, ONH VD loss shows a slightly stronger association with baseline VF than macular VD. Observing ONH VD loss with OCTA may help to monitor early glaucoma, which should be confirmed by future larger studies.