Retinal and choroidal vascular changes in coronary heart disease: an optical coherence tomography angiography study

Association of retinal microvascular curve tortuosity and multiple sclerosis: A cross-section analysis from the UK Biobank

BACKGROUND

There is growing evidence supporting that vascular abnormalities contribute to multiple sclerosis (MS), and retinal microvasculature functions as a visible window to observe vessels. We hypothesized that retinal vascular curve tortuosity is associated with MS, which this study aims to address.

METHODS

Participants from the UK Biobank with complete clinical records and gradable fundus photos were included in the study. Arteriolar and venular curve tortuosity and vessel area density are quantified automatically using a deep learning system. Individuals with MS were matched to healthy controls using propensity score matching (PSM). Conditional logistic regression was used to investigate the association between retinal vascular characteristics and MS. We also used a receiver operating characteristic (ROC) curve to assess the diagnostic performance of MS.

RESULTS

Venular curve tortuosity (VCT) was found to be significantly associated with MS. And patients with multiple sclerosis were probable to have lower VCT than the non-MS group (OR = 0.22 [95 % CI, 0.05 to 0.92], P < 0.05).

CONCLUSIONS

Our study reveals a significant association between vessel curve tortuosity and MS. The lower curve tortuosity of the retinal venular network may indicate a higher risk of incident multiple sclerosis.

Synthetic Optical Coherence Tomography Angiographs for Detailed Retinal Vessel Segmentation Without Human Annotations

Optical coherence tomography angiography (OCTA) is a non-invasive imaging modality that can acquire high-resolution volumes of the retinal vasculature and aid the diagnosis of ocular, neurological and cardiac diseases. Segmenting the visible blood vessels is a common first step when extracting quantitative biomarkers from these images. Classical segmentation algorithms based on thresholding are strongly affected by image artifacts and limited signal-to-noise ratio. The use of modern, deep learning-based segmentation methods has been inhibited by a lack of large datasets with detailed annotations of the blood vessels. To address this issue, recent work has employed transfer learning, where a segmentation network is trained on synthetic OCTA images and is then applied to real data. However, the previously proposed simulations fail to faithfully model the retinal vasculature and do not provide effective domain adaptation. Because of this, current methods are unable to fully segment the retinal vasculature, in particular the smallest capillaries. In this work, we present a lightweight simulation of the retinal vascular network based on space colonization for faster and more realistic OCTA synthesis. We then introduce three contrast adaptation pipelines to decrease the domain gap between real and artificial images. We demonstrate the superior segmentation performance of our approach in extensive quantitative and qualitative experiments on three public datasets that compare our method to traditional computer vision algorithms and supervised training using human annotations. Finally, we make our entire pipeline publicly available, including the source code, pretrained models, and a large dataset of synthetic OCTA images.

Oculomics: A Crusade Against the Four Horsemen of Chronic Disease

Chronic, non-communicable diseases present a major barrier to living a long and healthy life. In many cases, early diagnosis can facilitate prevention, monitoring, and treatment efforts, improving patient outcomes. There is therefore a critical need to make screening techniques as accessible, unintimidating, and cost-effective as possible. The association between ocular biomarkers and systemic health and disease (oculomics) presents an attractive opportunity for detection of systemic diseases, as ophthalmic techniques are often relatively low-cost, fast, and non-invasive. In this review, we highlight the key associations between structural biomarkers in the eye and the four globally leading causes of morbidity and mortality: cardiovascular disease, cancer, neurodegenerative disease, and metabolic disease. We observe that neurodegenerative disease is a particularly promising target for oculomics, with biomarkers detected in multiple ocular structures. Cardiovascular disease biomarkers are present in the choroid, retinal vasculature, and retinal nerve fiber layer, and metabolic disease biomarkers are present in the eyelid, tear fluid, lens, and retinal vasculature. In contrast, only the tear fluid emerged as a promising ocular target for the detection of cancer. The retina is a rich source of oculomics data, the analysis of which has been enhanced by artificial intelligence-based tools. Although not all biomarkers are disease-specific, limiting their current diagnostic utility, future oculomics research will likely benefit from combining data from various structures to improve specificity, as well as active design, development, and optimization of instruments that target specific disease signatures, thus facilitating differential diagnoses.

Ocular endothelial dysfunction in pediatric inflammatory bowel disease

OBJECTIVES

To assess ocular microvasculature changes using optical coherence tomography angiography (OCTA) in pediatric patients with inflammatory bowel disease (IBD).

METHODS

Patients (aged 6-18 years) with IBD were recruited between September 2021 and May 2023. All eligible participants underwent comprehensive clinical assessment and laboratory investigation. Patients with functional gastrointestinal disorders served as the controls. This study assessed specific IBD phenotypes, disease duration, clinical and endoscopic activity indices, laboratory markers, and medication histories. OCTA was utilized to evaluate ocular microvasculature changes in both groups.

RESULTS

A total of 63 children (mean age 12.9 ± 3.3 years) were enrolled, comprising 38 in the IBD group (16 ulcerative colitis, 22 Crohn's disease, and 25 in the control group). Most patients in the IBD group were in remission or had mild-to-moderate disease activity at enrollment. Analysis of the OCTA results revealed significant differences in the choroidal luminal area and total choroidal area between the IBD and control groups.

CONCLUSIONS

The study identified distinct ocular microvasculature changes in pediatric IBD patients through OCTA, suggestive of potential systemic endothelial dysfunction. These findings underscore the utility of OCTA in evaluating microvascular alterations associated with pediatric IBD, offering insights into potential systemic complications linked to inflammation in IBD patients.

Retinal microcirculation: A window into systemic circulation and metabolic disease

The retinal microcirculation system constitutes a unique terminal vessel bed of the systemic circulation, and its perfusion status is directly associated with the neural function of the retina. This vascular network, essential for nourishing various layers of the retina, comprises two primary microcirculation systems: the retinal microcirculation and the choroidal microcirculation, with each system supplying blood to distinct retinal layers and maintaining the associated neural function. The blood flow of those capillaries is regulated via different mechanisms. However, a range of internal and external factors can disrupt the normal architecture and blood flow within the retinal microcirculation, leading to several retinal pathologies, including diabetic retinopathy, macular edema, and vascular occlusions. Metabolic disturbances such as hyperglycemia, hypertension, and dyslipidemia are known to modify retinal microcirculation through various pathways. These alterations are observable in chronic metabolic conditions like diabetes, coronary artery disease, and cerebral microvascular disease due to advances in non-invasive or minimally invasive retinal imaging techniques. Thus, examination of the retinal microcirculation can provide insights into the progression of numerous chronic metabolic disorders. This review discusses the anatomy, physiology and pathophysiology of the retinal microvascular system, with a particular emphasis on the connections between retinal microcirculation and systemic circulation in both healthy states and in the context of prevalent chronic metabolic diseases.

The impact of serum BNP on retinal perfusion assessed by an AI-based denoising optical coherence tomography angiography in CHD patients

Background

To investigate the correlation between retinal vessel density (VD) parameters with serum B-type natriuretic peptide (BNP) in patients with coronary heart disease (CHD) using novel optical coherence tomography angiography (OCTA) denoising images based on artificial intelligence (AI).

Methods

OCTA images of the optic nerve and macular area were obtained using a Canon-HS100 OCT device in 176 patients with CHD. Baseline information and blood test results were recorded.

Results

Retinal VD parameters of the macular and optic nerves on OCTA were significantly decreased in patients with CHD after denoising. Retinal VD of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and radial peripapillary capillary (RPC) was strongly correlated with serum BNP levels in patients with CHD. Significant differences were noted in retinal thickness and retinal VD (SCP, DCP and RPC) between the increased BNP and normal BNP groups in patients with CHD.

Conclusion

Deep learning denoising can remove background noise and smooth rough vessel surfaces. SCP,DCP and RPC may be potential clinical markers of cardiac function in patients with CHD. Denoising shows great potential for improving the sensitivity of OCTA images as a biomarker for CHD progression.

Evaluation of retinal and choroidal thickness changes in overweight and obese adults without ocular symptoms by swept-source optical coherence tomography

AIM

To evaluate the relationship of overweight and obesity with retinal and choroidal thickness in adults without ocular symptoms by swept-source optical coherence tomography (SS-OCT).

METHODS

According to the body mass index (BMI) results, the adults enrolled in the cross-sectional study were divided into the normal group (18.50≤BMI<25.00 kg/m2), the overweight group (25.00≤BMI<30.00 kg/m2), and the obesity group (BMI≥30.00 kg/m2). The one-way ANOVA and the Chi-square test were used for comparisons. Pearson's correlation analysis was used to evaluate the relationships between the measured variables.

RESULTS

This research covered the left eyes of 3 groups of 434 age- and sex-matched subjects each: normal, overweight, and obesity. The mean BMI was 22.20±1.67, 26.82±1.38, and 32.21±2.35 kg/m2 in normal, overweight and obesity groups, respectively. The choroid was significantly thinner in both the overweight and obesity groups compared to the normal group (P<0.05 for all), while the retinal thickness of the three groups did not differ significantly. Pearson's correlation analysis showed that BMI was significantly negatively correlated with choroidal thickness, but no significant correlation was observed between BMI and retinal thickness.

CONCLUSION

Choroidal thickness is decreased in people with overweight or obesity. Research on changes in choroidal thickness contributes to the understanding of the mechanisms of certain ocular disorders in overweight and obese adults.

Associations between the retinal/choroidal microvasculature and carotid plaque in patients with CAD: An OCTA study

Background

To investigate the associations between retinal/choroidal microvasculature and carotid plaque in patients with CAD assessed by optical coherence tomography angiography (OCTA).

Methods

This study included 127 CAD patients with and 79 without carotid plaque. Each patient had both OCTA taken and digitized to determine retinal/choroidal thickness, vessel density and flow area and carotid ultrasound for carotid plaque size and stability measurement. The superficial capillary plexus (SCP), deep capillary plexus (DCP), out retina and choriocapillaris vessel density, out retina and choriocapillaris flow area, and full retina thickness were analyzed in the fovea centered 6 × 6 mm area. The association between OCTA measurements and carotid plaque characteristics in patients with CAD were evaluated.

Results

The duration of hypertension and diabetes mellitus (DM) was significantly longer in CAD patients with carotid plaque than that without (p < 0.001). The mean values for vessel density SCP and DCP (except fovea zone), and choriocapillaris nasal zone were significantly lower in plaque group (p < 0.05). Negative correlations between the carotid plaque width and vessel density SCP and DCP (except fovea zone) (p < 0.05) were also found in this study.

Conclusions

In patients with CAD, carotid plaque, a risk factor and marker of atherosclerosis and stenosis, is significantly and independently associated with retinal and choroidal microvascular changes by OCTA.

Retinal Structural and Vascular Changes in Patients with Coronary Artery Disease: A Systematic Review and Meta-Analysis

BACKGROUND

Retinal microvascular anomalies have been identified in patients with cardiovascular conditions such as arterial hypertension, diabetes mellitus, and carotid artery disease. We conducted a systematic review and meta-analysis (PROSPERO registration number CRD42024506589) to explore the potential of retinal vasculature as a biomarker for diagnosis and monitoring of patients with coronary artery disease (CAD) through optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA).

METHODS

We systematically examined original articles in the Pubmed, Embase, and Web of Science databases from their inception up to November 2023, comparing retinal microvascular features between patients with CAD and control groups. Studies were included if they reported sample mean with standard deviation or median with range and/or interquartile range (which were computed into mean and standard deviation). Review Manager 5.4 (The Cochrane Collaboration, 2020) software was used to calculate the pooled effect size with weighted mean difference and 95% confidence intervals (CI) by random-effects inverse variance method.

RESULTS

Eleven studies meeting the inclusion criteria were incorporated into the meta-analysis. The findings indicated a significant decrease in the retinal nerve fiber layer (WMD -3.11 [-6.06, -0.16]), subfoveal choroid (WMD -58.79 [-64.65, -52.93]), and overall retinal thickness (WMD -4.61 [-7.05, -2.17]) among patients with CAD compared to controls (p < 0.05). Furthermore, vascular macular density was notably lower in CAD patients, particularly in the superficial capillary plexus (foveal vessel density WMD -2.19 [-3.02, -1.135], p < 0.0001). Additionally, the foveal avascular zone area was statistically larger in CAD patients compared to the control group (WMD 52.73 [8.79, 96.67], p = 0.02). Heterogeneity was significant (I2 > 50%) for most features except for subfoveal choroid thickness, retina thickness, and superficial foveal vessel density.

CONCLUSION

The current meta-analysis suggests that retinal vascularization could function as a noninvasive biomarker, providing additional insights beyond standard routine examinations for assessing dysfunction in coronary arteries.

Inflammatory mechanisms contributing to retinal alterations in HIV infection and long-term ART

People living with HIV (PLWH) may face an increased risk of eye complications associated with ageing, chronic inflammation, and the toxicity arising from long-term antiretroviral therapy (ART). This review aims to understand how inflammatory pathways contribute to retinal alterations observed in PLWH on long-term ART. This review was conducted using four electronic database searches, namely Scopus, Hinari, Google Scholar, and PubMed; from 1996 (when ART became available) until January 2022, without language restriction. Sources from clinical trials, meta-analyses, randomised controlled trials, and systematic reviews were used. Dysregulated para-inflammation (chronic inflammation) damages the blood-retina barrier, resulting in the altered retinal immune privilege and leading to the development of retinal and blood vessel changes. There is an interplay between the effects of the disease versus ART. ART causes mitochondrial toxicity, which affects the retinal ganglion cells and retinal pigment epithelium (RPE) due to oxidative stress. Infection by HIV also affects retinal microglia, which contributes to RPE damage. Both of these mechanisms affect the blood vessels. Assessing the integrity of the inner and outer blood-retina barrier is a pivotal point in pinpointing the pathogenesis of inner retinal alterations. Optical coherence tomography is a valuable tool to assess these changes. There is a paucity of research to understand how these structural changes may affect visual function, such as contrast sensitivity and colour vision.

Quantitative evaluation of choroidal and retinal microvasculature post-alcohol consumption: A pilot study

PURPOSE

The aim of this study was to assess the impact of acute, heavy alcohol consumption on the ocular microvasculature, providing insight into the largely unexplored response of microvascular structures to excessive drinking.

METHODS

Healthy volunteers in this prospective pilot study were tasked with consuming spirits, wine, and water at different times. Alcohol intake was measured according to body weight (g/kg). The ocular microvascular parameters primarily including choroidal volume (CV) and choroidal vessel volume (CVV) reflecting arteriolovenularity, and choroidal capillary density (CCD) reflecting capillary, were evaluated using swept-source optical coherence tomography angiography at baseline and 0.5-, 1-, 2-, and 3-hour post-consumption.

RESULTS

A total of 34 eyes underwent 170 successful examinations in this study. After consuming spirits or wine, we observed significant decreases in CV and CVV values (all P < 0.01 for 0.5-, 1-, 2-, and 3-hour post-consumption), along with significant increase in CCD (P < 0.05 at 0.5-, 1-, 2-hour post-spirits consumption and 1-hour post-wine consumption). The most pronounced changes occurred 1-hour after spirits or wine consumption (all P < 0.001 in both univariate and multivariate model). However, post-consumption changes in the ocular microvasculature showed no significant differences between spirits and wine (P > 0.05). Additionally, no significant differences were observed in any parameters after water intake (all P > 0.05).

CONCLUSIONS

Excessive alcohol consumption leads to ocular arteriolovenular vasoconstriction and capillary vasodilation, most evident 1-hour post-consumption of spirits and wine. Our research provides insight into alcohol's immediate ocular microvascular effects, hinting at systemic microvascular effects.

Ocular microvascular alteration in patients with myocardial infarction-a new OCTA study

Myocardial infarction is defined as a sudden decrease or interruption in blood flow to the coronary arteries, causing ischemic necrosis of the corresponding cardiomyocytes. It is unclear whether systemic macrovascular alterations are associated with retinal microvascular changes. This study utilized optical coherence tomography angiography (OCTA) to compare variations in conjunctival vascular density and fundus retinal vessel density between patients with myocardial infarction (MI) and healthy controls. This study recruited 16 patients (32 eyes) with MI and 16 healthy controls (32 eyes). The superficial retinal layer (SRL), deep retinal layer (DRL) and conjunctival capillary plexus in each eye were evaluated by OCTA. Parameters measured included the density of the temporal conjunctival capillary, retinal microvascular (MIR) and macrovascular (MAR) alterations and total MIR (TMI). The microvascular density of each retinal region was evaluated by the hemisphere segmentation (SR, SL, IL, and IR), annular partition (C1, C2, C3, C4, C5 and C6), and modified early treatment of diabetic retinopathy study (R, S, L, and I) methods. In the macular area, the superficial and deep retinal microvascular densities displayed notable variations. In the superficial layers, the superficial TMI, superficial MIR, and superficial MAR, as well as densities in the SL, IL, S, L, C1, C2, C5 and C6 regions, were significantly lower in MI patients (p < 0.05 each). In the deep layers, the deep MIR and deep TMI), as well as densities in the SL, IL, L, C1, C2 and C6 regions were significantly lower in MI patients (p < 0.05 each). In contrast, the conjunctival microvascular density was significantly higher in MI patients than in healthy controls (p < 0.001). The microvascular densities measured in the deep and superficial retinal layers and in the conjunctiva differ in MI patients and healthy controls. OCTA is effective in detecting changes in the ocular microcirculation.

Coronary artery disease, its associations with ocular, genetic and blood lipid parameters

BACKGROUND/OBJECTIVES

To investigate the associations between ophthalmic parameters, CYP4F2 (rs2108622) and ABCA1 (rs1883025) polymorphisms and coronary artery disease, considering the accessibility, non-invasive origin of retinal examination and its possible resemblance to coronary arteries.

SUBJECTS/METHODS

Overall 165 participants divided into groups based on the coronary angiography results and clinical status: control group (N = 73), MI group (N = 63), 3VD (three vessel disease) (N = 24). All the participants underwent total ophthalmic examination - optical coherence tomography (OCT) and OCT angiography of the macula region were performed and evaluated. Total cholesterol, high-density lipoprotein, low-density lipoprotein and triglyceride cholesterol (Tg-C) were tested. A standard manufacturer's protocol for CYP4F2 (rs2108622) and ABCA1 (rs1883025) was used for genotyping with TaqMan probes.

RESULTS

GCL+ layer was thicker in control group vs. 3VD group (74.00; 62.67-94.67 (median; min.-max.) vs. 71.06; 51.33-78.44, p = 0.037). T allele carriers under ABCA1 rs1883025 dominant model were shown to have ticker retina and smaller foveal avascular zone in superficial capillary plexus and smaller Tg-C concentration. ABCA1 rs1883025 was associated with retinal thickness (OR = 0.575, 95% CI 0.348-0.948, p = 0.030). Univariate logistic regression showed that ABCA1 rs1883025 CT genotype is associated with decreased risk for coronary artery disease development under overdominant genetic model (OR = 0.498, 95% CI 0.254-0.976; p = 0.042) and codominant genetic model (OR = 0.468, 95% CI 0.232-0.945, p = 0.034).

CONCLUSIONS

Results of this study confirmed that non-invasive methods such as OCT of eye might be used for identification of patients at risk of CAD.

Internal Carotid Artery Stenosis and Ipsilateral Subretinal Drusenoid Deposits

Purpose

Subretinal drusenoid deposits (SDDs) in age-related macular degeneration (AMD) are strongly associated with vasculopathies such as myocardial infarction and ischemic stroke. This study evaluates ischemic stroke subjects for SDDs to determine whether ocular hypoperfusion from internal carotid artery (ICA) stenosis is associated with ipsilateral SDDs.

Methods

A cross-sectional study at Mount Sinai Hospital recruited 39 subjects with ischemic stroke (aged 52-90; 18 women, 21 men); 28 completed all study procedures. Computed tomography (CT) of the head and neck evaluated 54/56 ICAs for stenosis criteria: none (n = 33), mild (n = 12), moderate (n = 3), severe (n = 3), and complete (n = 3). Spectral-domain optical coherence tomography (SD-OCT) scans were read to consensus by two masked graders for soft drusen, SDDs and choroidal thickness (CTh; choroidal thinning = CTh < 250 µm). Univariate testing was done with Fisher's exact test. Multivariate logistic regression models tested age, gender, and ICA stenosis as covariates.

Results

Moderate or more ICA stenosis (≥50%-69%) was significantly associated with ipsilateral choroidal thinning (P = 0.021) and ipsilateral SDDs (P = 0.005); the latter were present distal to six of nine stenosed ICAs versus five of 33 normal ICAs. Mild ICA stenosis (≥1%-49%) was not significantly associated with ipsilateral SDDs. Multivariate regression found that older age (P = 0.015) and moderate or more ICA stenosis (P = 0.011) remained significant independent risks for ipsilateral SDDs.

Conclusions

At least moderate ICA stenosis (≥50%-69%) is strongly associated with ipsilateral SDDs and choroidal thinning, supporting downstream ophthalmic artery and choroidal hypoperfusion from ICA stenosis as the mechanism for SDD formation. SDDs may thus serve as sensitive biomarkers for ischemic stroke and other vascular diseases.

RETINAL MICROVASCULAR CHANGES AND RISK OF CORONARY HEART DISEASE: A Systematic Review and Meta-Analysis

PURPOSE

To quantify associations between various retinal microvascular changes and the risk of the development of coronary heart disease (CHD).

METHODS

PubMed, Embase, Web of Science, and Cochrane Library databases were searched for cohort studies on the association between retinal microvascular changes and incident CHD up to July 31, 2023. The summary risk estimates were estimated using the random-effects model. Subgroup and sensitivity analyses were performed to investigate the potential source of heterogeneity.

RESULTS

The authors identified 21 studies that met the inclusion criteria of this meta-analysis through database searching. This study yielded significant associations between retinal microvascular changes, including arteriolar narrowing, venular widening, vessel occlusion, and other retinal vascular signs, and the risk of CHD, with pooled adjusted hazard ratios of 1.20 (95% confidence interval: 1.13-1.27). In sex- and age-stratified analyses, retinal microvascular changes were associated with a greater risk of developing CHD in female patients and younger adults.

CONCLUSION

A range of retinal microvascular changes was associated with the risk of CHD, particularly in female patients and younger ages. The results of this study support the concept that retinal microvascular abnormalities may be markers for future CHD. Noninvasive retinal microvascular assessments may be helpful in screening patients with increased CHD risk.

Optical Coherence Tomography Angiography Changes in Patients Diagnosed With Acute Coronary Syndrome: A Systematic Review and Meta-Analysis

We conducted a systematic review and meta-analysis to assess the association between optical coherence tomography angiography (OCTA) parameters and acute coronary syndrome (ACS). Two independent reviewers searched the electronic databases (MEDLINE (Medical Literature Analysis and Retrieval System Online), Scopus, Embase (Excerpta Medica Database), Cochrane Library, ClinicalTrials.gov, and World Health Organization International Clinical Trials Registry Platform) from inception until April 2023. According to the inclusion criteria of this review, eligible were observational studies, randomized control trials, and registry/database studies that included the eyes of adult ACS patients and assessed OCTA parameters within the macula. The pooled standardized mean differences (SMD) between patients diagnosed with ACS and healthy controls with a confidence interval (CI) of 95% were calculated using the Hartung-Knapp-Sidik-Jonkman random-effects method. The heterogeneity was assessed by I2 and the Cochran Q and a random effects model was applied. Seven studies were eligible and included in our systematic review (n = 898), of which three were included in the meta-analysis (n = 341). The pooled SMD in the superficial vascular plexus (SVP), deep vascular plexus (DVP), and foveal avascular zone (FAZ) were -0.46 (95% CI: -0.94 to 0.01, p = 0.05, I2 = 0%, three studies), -0.10 (95% CI: -3.20 to 3.00, p = 0.75, I2 = 67%, two studies), and 0.43 (95% CI: -1.22 to 2.09, p = 0.38, I2 = 92%, three studies), respectively. Our findings suggest that there are no differences in OCTA metrics between ACS patients and healthy individuals.

A prospective observation of influence of anti-VEGF on optic disc vasculature in nAMD patients

BACKGROUND

This study aims to investigate the short-term changes in relatively normal retinal vessels following anti-vascular endothelial growth factor (anti-VEGF) therapy in nAMD patients, an area that currently represents a research gap.

METHODS

In this prospective study, we enrolled patients newly diagnosed with neovascular age-related macular degeneration (nAMD) and received standardized monthly anti-VEGF therapy for three months. Follow-ups were conducted at baseline and 1-week, 1-month, 2-months and 3-months post first injection. Assessment indicators included radial peripapillary capillary vascular density (RPC-VD) and retinal nerve fiber layer (RNFL) thickness in different optic disk regions using optical coherence tomography angiography, as well as intraocular pressure (IOP).

RESULTS

68 nAMD patients (68 eyes) were included in this study. Significant reductions of RPC-VD and increases of RNFL thickness primarily in the nasal regions were observed 1-week post anti-VEGF (adjusted P < 0.05). Significant negative correlations were found between 1-week changes in RPC-VD and RNFL thickness in the nasal sectors (P < 0.05). From 1 to 3 months post-injection, RPC-VD and RNFL thickness essentially returned to baseline levels. Throughout the follow-up periods, IOP remained stable (P > 0.05).

CONCLUSION

Anti-VEGF treatments transiently influence the relatively normal retinal vessels, which might lead to nerve fiber edema, predominantly on the nasal side of the optic disk.

The Eye as the Window to the Heart: Optical Coherence Tomography Angiography Biomarkers as Indicators of Cardiovascular Disease

Alterations in microvasculature represent some of the earliest pathological processes across a wide variety of human diseases. In many organs, however, inaccessibility and difficulty in directly imaging tissues prevent the assessment of microvascular changes, thereby significantly limiting their translation into improved patient care. The eye provides a unique solution by allowing for the non-invasive and direct visualization and quantification of many aspects of the human microvasculature, including biomarkers for structure, function, hemodynamics, and metabolism. Optical coherence tomography angiography (OCTA) studies have specifically identified reduced capillary densities at the level of the retina in several eye diseases including glaucoma. This narrative review examines the published data related to OCTA-assessed microvasculature biomarkers and major systemic cardiovascular disease. While loss of capillaries is being established in various ocular disease, pilot data suggest that changes in the retinal microvasculature, especially within the macula, may also reflect small vessel damage occurring in other organs resulting from cardiovascular disease. Current evidence suggests retinal microvascular biomarkers as potential indicators of major systemic cardiovascular diseases, including systemic arterial hypertension, atherosclerotic disease, and congestive heart failure.

Evaluation of retinal and peripapillary vessel density and subfoveal choroidal thickness changes in patients undergoing cardiopulmonary bypass: An OCTA study

PURPOSE

We aimed to investigate hemodynamic changes in the retina, peripapillary area, and choroid in patients undergoing coronary artery bypass grafting (CABG).

METHODS

This prospective case series included 35 eyes of 35 patients. Vessel density (VD) of superficial capillary plexus, deep capillary plexus, radial peripapillary capillary, foveal avascular zone area, and subfoveal choroidal thickness changes were evaluated using optical coherence tomography angiography (OCTA) 1 day before and 2 weeks after surgery. The correlation of these parameters with aortic cross-clamp (ACC) duration and cardiopulmonary bypass (CPB) duration was evaluated.

RESULTS

There were no differences in the OCTA measurements of the patients after CABG compared to before surgery (P > 0.05). Inside-disc VD showed a negative correlation with both ACC (P = 0.036) and CPB duration (P = 0.048); peripapillary inferior hernia showed a negative correlation with both ACC (P = 0.042) and CPB duration (P = 0.027). Another negative correlation was observed between mean peripapillary VD and CPB duration (P = 0.039).

CONCLUSION

The CPB procedure had no permanent effect on retinal choroid and optic disc blood flow postoperatively. Prolonged ACC and CPB times seem to be important in terms of optic nerve blood flow. Clinicians should be alert for postoperative ocular complications after long surgeries.

Botulinum toxin type A in multimodal management of age-related macular degeneration and related diseases

Age related macular degeneration (AMD) is the major cause of visual loss in the aging population in the Western world. In past decade, intra ocular injections of anti-vascular endothelial growth factor (anti-VEGF) pharmaceuticals have revolutionized therapy for exudative (edematous-wet) AMD and become standard practice for the near term. However repeated intra-ocular injections are required for years and long terms results have been limited. The pathogenesis of this condition is multifactorial involving genetic, ischemic, inflammatory factors leading to neovascularization, edema and retinal pigment epithelial scaring resulting in photoreceptor destruction. Based on coincidental observation in reduction in AMD related macular edema on ocular coherence tomography (OCT) in a BoNT A treated patient with facial movement disease, BoNT-A at conventional doses targeting the para orbital area was added to therapeutic regiment in a small number of patients with exudative macular degeneration or related diseases. Measurements of edema and choriocapillaris using Spectral Doman (OCT) and Ocular Coherence Angiography (OCT-A) and Snellen visual acuity were made over the evaluation period. 15 eyes in 14 patients averaged 361 μm central sub foveal edema (CSFT) pre injection and average of 266 μm (CSFT) post injection over an average of 21 months and 5.7 cycles using BoNT A alone at conventional doses (n = 86 post injection measurements, paired t-test p < 0.001 two tailed). Visions at baseline in patients with 20/40 or worse averaged 20/100- pre injection improved to an average of 20/40- in the post injection period (n = 49 measurements p < 0.002 paired t-test). The previous data was added to a group of 12 more severely afflicted patients receiving anti VEGF (aflibercept or bevacizumab) (total 27 patients). With this 27-patient group, patients were followed for an average of 20 months and receiving average of 6 cycles at conventional doses. Improvement in exudative edema and vision were noted with pre injection baseline CSFT average 399.5, post injection average 267, n = 303 post measurement, independent t-test P < 0.0001.). Snellen vision 20/128 baseline average improved to average of 20/60- during post injection period (n = 157 post injection measurements, p < 0.0001 paired t-test to baseline). No substantial adverse effects were noted. Cyclic effects were noted corresponding to duration of action of BoNT-A on a number of patients. The above data is preliminary and is skewed toward early leakage for all conditions. BoNT A may have a role in the treatment of aged related macular degeneration. Controlled studies are needed with careful staging and baseline stratifications for multi-modal management paradigms. The findings are discussed relative to known botulinum toxin type A pharmacology and AMD pathogenesis.

The clinical implications of choroidal thickness combined with tear VEGFA in coronary artery disease

OBJECTIVE

The purpose of this study was to evaluate the effect of choroidal thickness and tear vascular endothelial growth factor A (VEGFA) as biomarkers of coronary artery disease (CAD).

METHODS

This study was a retrospective observational case-control trial. A total of 637 patients who underwent coronary angiography to assess their coronary artery status were included. The patients were divided into two groups: 200 people in the No CAD group and 437 people in the CAD group. We evaluated the choroidal thickness of the right foveal membrane in all patients through optical coherence tomography angiography examination. We also collected tear samples from patients to measure VEGFA. The ROC curve and its area under the curve (AUC) were used for analysis.

RESULTS

The central foveal choroid in the No CAD group was significantly thicker than that in the CAD group (289.09 μm ± 38.41; 229.03 μm ± 33.44, P  < 0.01). The tear VEGFA in the CAD group was higher than that in the No CAD group (706.15 ng/mL ± 147.42; 419.66 ng/mL ± 105.85, P  < 0.01). Spearman analysis showed that the correlation between choroidal thickness and Gensini score was -0.7387 ( P  < 0.01). The correlation between tear VEGFA level and Gensini score was 0.8636 ( P  < 0.01). Taking choroidal thickness and tear VEGFA as independent variables, we obtained AUC = 0.9647 (95% CI 0.9506-0.9789, P  < 0.01) through binary logic regression and ROC curve analysis.

CONCLUSION

The combination of choroidal thickness and tear VEGFA in patients can serve as a clinical marker of CAD and its severity.

Retinal Findings and Cardiovascular Risk: Prognostic Conditions, Novel Biomarkers, and Emerging Image Analysis Techniques

Many retinal diseases and imaging findings have pathophysiologic underpinnings in the function of the cardiovascular system. Myriad retinal conditions, new imaging biomarkers, and novel image analysis techniques have been investigated for their association with future cardiovascular risk or utility in cardiovascular risk prognostication. An intensive literature search was performed to identify relevant articles indexed in PubMed, Scopus, and Google Scholar for a targeted narrative review. This review investigates the literature on specific retinal disease states, such as retinal arterial and venous occlusions and cotton wool spots, that portend significantly increased risk of future cardiovascular events, such as stroke or myocardial infarction, and the implications for personalized patient counseling. Furthermore, conditions diagnosed primarily through retinal bioimaging, such as paracentral acute middle maculopathy and the newly discovered entity known as a retinal ischemic perivascular lesion, may be associated with future incident cardiovascular morbidity and are also discussed. As ever-more-sophisticated imaging biomarkers and analysis techniques are developed, the review concludes with a focused analysis of optical coherence tomography and optical coherence tomography angiography biomarkers under investigation for potential value in prognostication and personalized therapy in cardiovascular disease.

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.

Correlation of RETINAL Artery Diameter with Coronary Artery Disease: The RETINA CAD Pilot Study-Are the Eyes the Windows to the Heart?

INTRODUCTION

This study aimed to determine whether there was any correlation between coronary artery disease (CAD) and retinal artery diameter at an academic tertiary medical center in Trinidad and Tobago.

METHODS

This prospective study evaluated patients (n = 77) with recent invasive coronary angiography (CAG) and the Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score who subsequently underwent optical coherence tomography-angiography (OCT-A) at the Eric Williams Medical Sciences Complex (EWMSC) from January 2021 to March 2021. Routine medical history and cardiovascular medications were also recorded. Spearman's rank correlation coefficient and Mann-Whitney U-tests were used to compare correlations and medians between groups.

RESULTS

The average patient age was 57.8 years old, with the majority being male [n = 55 (71.4%)] and of South Asian ethnicity [n = 53 (68.8%)]. Retinal artery diameter was negatively correlated with the SYNTAX score (-0.332 for the right eye, p = 0.003 and -0.237 for the left eye, p = 0.038). A statistically significant relationship was also demonstrated in females and diabetic patients. There were no serious adverse events (SAEs).

CONCLUSION

A significantly negative correlation was observed between retinal artery diameter and SYNTAX score. This study alludes to the practical use of optical coherence tomography-angiography (OCT-A) as a noninvasive diagnostic modality for patients with cardiovascular disease (CVD). Further large-scale, multicentric studies are required to confirm these exploratory findings.

TRIAL REGISTRATION NUMBER

NCT04233619.

Retinal Vascular Density Change in Patients With Aortic Valve Regurgitation

BACKGROUND

The aim of this study was to assess retinal vessel density in the superficial capillary plexus layer, deep capillary plexus layer and choriocapillaris plexus layer in patients with aortic valve regurgitation (AR) using optical coherence tomography angiography (OCTA).

METHODS

Thirty-eight healthy participants (group 1) and 38 patients with AR (group 2) were assessed for this study. Diagnosis of AR is made by transthoracic echocardiography (TTE). Severity of AR was assessed according to values in the 2014 American Heart Association/American College of Cardiology (AHA/ACC) valve guideline. Superficial capillary plexus density (SCPD), deep capillary plexus density (DCPD) and choriocapillaris plexus density (CCPD) were analyzed between groups using OCTA.

RESULTS

SCPD measurements were found to be decreased in the nasal, inferior and central regions of patients with AR (P ≤ 0.05). DCPD measurements were found to be decreased in the nasal and inferior regions of patients with AR (P ≤ 0.05). CCPD measurements were found to be decreased in the inferior and central regions of patients with AR (P ≤ 0.05). In patients with AR, CCPD measurements were significantly decreased in the inferior region compared to the control group. Central macular thickness was found to be significantly decreased in the patients with AR.

CONCLUSIONS

Patients with AR showed decreased flow density compared with healthy controls. Retinal perfusion measured using OCTA in patients with AR may give an idea about microperfusion.

Age-Related Macular Degeneration With Visual Disability Is Associated With Cardiovascular Disease Risk in the Korean Nationwide Cohort

Background Age-related macular degeneration (AMD) is the leading cause of visual disability. AMD shares some risk factors with the pathogenesis of cardiovascular disease (CVD). However, previous studies examining the association between AMD and the risk of CVD provide conflicting results. Hence, we investigated the association between AMD, visual disability, and the risk of CVD. Methods and Results This is a nationwide cohort study using data from the Korean National Health Insurance System database (2009-2019) on subjects who underwent a national health screening program in 2009. A total of 3 789 963 subjects were categorized by the presence of AMD and visual disability. Visual disability was defined as a best-corrected visual acuity of ≤20/100 by validated documentation from a specialist physician. Cox regression hazard model was used to examine the hazard ratios (HRs) of CVD, including myocardial infarction and ischemic stroke, after adjusting for potential confounders. During a mean 9.77 years of follow-up, AMD was associated with a 5% higher risk of myocardial infarction (adjusted HR [aHR], 1.05 [95% CI, 1.01-1.10]) but not associated with increased risk of overall CVD (aHR, 1.02 [95% CI, 1.00-1.05]) or ischemic stroke (aHR, 1.02 [95% CI, 0.98-1.06]). However, when AMD was accompanied by visual disability, there was increased risk of CVD (aHR, 1.17 [95% CI, 1.06-1.29]), myocardial infarction (aHR, 1.18 [95% CI, 1.01-1.37]), and ischemic stroke (aHR, 1.20 [95% CI, 1.06-1.35]). These trends were more evident in women and subjects with cardiometabolic comorbidities. Conclusions AMD with visual disability, but not all AMD, was associated with an increased risk of CVD. Patients with AMD who have visual disability should be targeted for CVD prevention.

Correlation Between Coronary and Retinal Microangiopathy in Patients With STEMI

Purpose

To investigate the morphological and functional correlation between microvascular retinal changes in optical coherence tomography angiography (OCTA) and the microvascular coronary circulation in patients with ST elevation myocardial infarction (STEMI) coronary heart disease (CHD).

Methods

A total of 330 eyes from 165 participants (88 cases and 77 controls) were enrolled and imaged. Superficial capillary plexus (SCP) and deep capillary plexus (DCP) vascular density was measured in the central (1 mm) and perifoveal (1-3 mm) areas and in the superficial foveal avascular zone (FAZ) and choriocapillaris (3 mm). These parameters were then correlated to the left ventricular ejection fraction (LVEF), and the number of affected coronary arteries.

Results

Decreased vessel densities in the SCP and DCP and choriocapillaris were positively correlated to the LVEF values (P = 0.006, P = 0.026, and P = 0.002, respectively). No statistically significant correlation between the SCP and DCP central area or FAZ area was found. Regarding the number of affected vessels, significant negative correlations were revealed for the SCP and DCP central vessel densities (P < 0.001 and P < 0.001, respectively) and the SCP perifoveal vascular density (P = 0.009).

Conclusions

OCTA vascular indices are significantly correlated with morphological and functional parameters in patients with STEMI CHD. SCP vascular density especially seems to be a promising biomarker for the extent of both macrovascular damage (number of affected coronary arteries) and microvascular damage, as mirrored in the decreased LVEF at admission.

Translational Relevance

OCTA vascular indices offer a valuable insight into the microvascular status of coronary circulation.

Microvascular and structural analysis of the retina and choroid in heart failure patients with reduced ejection fraction

This cross-sectional study was designed to assess alterations of choroidal and retinal microvasculature in patients with Heart Failure with Reduced Ejection Fraction (HFrEF) and compare them with a normal age and sex-matched population. Fifty-two eyes of 26 patients with HFrEF (left ventricular ejection fraction [LVEF] < 40%) and 64 eyes of 32 healthy individuals were considered as the patient and the control groups, respectively. We found no statistically significant differences in age-adjusted mean central macular thickness (CMT), superficial or deep retinal capillary plexus vascular densities, and choriocapillaris flow (CC flow) density between the HFrEF group and the normal controls, with the exception of the parafoveal mean superficial capillary plexus vascular density (P = 0.023), which remained statistically significant after adjusting for age (P = 0.034). The patients with HFrEF had a significantly lower subfoveal choroidal thickness (SFCT) than the normal subjects (264 ± 82 vs 313 ± 72; P = 0.009), and the difference was still statistically significant after age adjustment (P = 0.026). Although choroidal vascularity index (CVI) was lower in the HFrEF group than in the control group, the difference was not statistically significant before and after age adjustment (73.45 ± 6.67 vs 75.77 ± 5.92; P = 0.118 and P = 0.096, respectively). In conclusion, in patients with HFrEF, we observed a reduction in parafoveal retinal VD in the superficial capillary plexus, as well as SFCT, but no significant change in CVI, CMT, or CC flow density.

Using Artificial Intelligence to Analyse the Retinal Vascular Network: The Future of Cardiovascular Risk Assessment Based on Oculomics? A Narrative Review

The healthcare burden of cardiovascular diseases remains a major issue worldwide. Understanding the underlying mechanisms and improving identification of people with a higher risk profile of systemic vascular disease through noninvasive examinations is crucial. In ophthalmology, retinal vascular network imaging is simple and noninvasive and can provide in vivo information of the microstructure and vascular health. For more than 10 years, different research teams have been working on developing software to enable automatic analysis of the retinal vascular network from different imaging techniques (retinal fundus photographs, OCT angiography, adaptive optics, etc.) and to provide a description of the geometric characteristics of its arterial and venous components. Thus, the structure of retinal vessels could be considered a witness of the systemic vascular status. A new approach called "oculomics" using retinal image datasets and artificial intelligence algorithms recently increased the interest in retinal microvascular biomarkers. Despite the large volume of associated research, the role of retinal biomarkers in the screening, monitoring, or prediction of systemic vascular disease remains uncertain. A PubMed search was conducted until August 2022 and yielded relevant peer-reviewed articles based on a set of inclusion criteria. This literature review is intended to summarize the state of the art in oculomics and cardiovascular disease research.

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

BACKGROUND

To investigate retinal and optic disc 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.

METHODS

104 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 disc microcirculation.

RESULTS

The 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).

CONCLUSIONS

Using OCTA, a non-invasive imaging technique, to assess retinal and optic disc microcirculation appears to have the potential to yield significant clinical results in the early diagnosis or prognosis of cardiovascular diseases.

Retinal microvascular changes in patients with coronary artery disease and apnea

BACKGROUND

Optical coherence tomography angiography (OCT-A) allowed visualization of capillary level of retina; however, the relationship between coronary vascular status and retinal microvascular changes in patients with apnea is not known well. Our aim was to assess the retinal OCT-A parameters in patients with ischemia and angiographically proven microvascular disease and compare them with obstructive coronary disease in patients with apnea.

METHODS

Our observational study included 185 eyes of 185 patients, 123 eyes of patients with apnea (72 eyes from mild OSAS, 51 eyes from moderate to severe OSAS) and 62 eyes from healthy controls. Radial scans of the macula and OCT-A scans of the central macula (superficial (SCP) and deep (DCP) capillary plexuses) were performed on all participants. All participants had documented sleep apnea disorder within 2 years prior to coronary angiography. Patients were grouped by severity of apnea and coronary atherosclerosis (50 % stenosis cut-off value for obstructive coronary artery disease). Patients presented with myocardial ischemia and without coronary artery occlusion (<50 % diameter reduction or FFR > 0.80) constitute the microvascular coronary artery (INOCA) group.

RESULTS

Compared to healthy controls, patients with apnea showed deterioration in vascular density in all regions of the retina, regardless of obstructive or microvascular coronary artery disease on the ischemia background. This study has provided important observations of a high prevalence of INOCA in patients with OSAS and the presence of OSAS was a significant independent predictor of functional coronary artery disease. The relative decreases in vascular densities were more pronounced in the DCP layer according to SCP layer of macula. Only FAZ area values were significantly different according to the severity of OSAS (0.27 (0.11-0.62) and 0.23 (0.07-0.50) (p = 0.012)).

CONCLUSIONS

In patients with apnea, OCT-A can be used as a noninvasive tool to define coronary artery involvement, with similar retinal microvascular changes both in obstructive and microvascular coronary artery group. In patients with OSAS, we observed a high prevalence of microvascular coronary disease, supporting pathophysiological role of OSAS in ischemia of this group of patients.

Impaired retinal microcirculation in patients with non-obstructive coronary artery disease

PURPOSE

To quantitatively investigate alterations of retinal microcirculation in patients with non-obstructive coronary artery disease (NOCAD) using optical coherence tomography angiography (OCTA), and to identify the ability of retinal microcirculation parameters in differentiating coronary artery disease (CAD) subtypes.

METHODS

All participants with angina pectoris underwent coronary computed tomography angiography. Patients with lumen diameter reduction of 20-50 % in all major coronary arteries were defined as NOCAD, while patients with at least one major coronary artery lumen diameter reduction ≥ 50 % were recruited as obstructive coronary artery disease (OCAD). Participants without a history of ophthalmic or systemic vascular disease were recruited as healthy controls. Retinal neural-vasculature was measured quantitatively by OCTA, including peripapillary retinal nerve fiber layer (RNFL) thickness and vessel density (VD) of the optic disc, superficial vessel plexus (SVP), deep vessel plexus (DVP), and foveal density (FD 300). p < 0.017 is considered significant in multiple comparisons.

RESULTS

A total of 185 participants (65 NOCAD, 62 OCAD, and 58 controls) were enrolled. Except for the DVP fovea (p = 0.069), significantly reduced VD in all other regions of SVP and DVP was detected in both the NOCAD and OCAD groups compared to control group (all p < 0.017), while a more significant decrease was found in OCAD compared to NOCAD. Multivariate regression analysis showed that lower VD in superior hemi part of whole SVP (OR: 0.582, 95 % CI: 0.451-0.752) was an independent risk factor for NOCAD compared to controls, while lower VD in the whole SVP (OR: 0.550, 95 % CI: 0.421-0.719) was an independent risk factor for OCAD compared to NOCAD. Using the integration of retinal microvascular parameters, the area under the receiver operating characteristic curve (AUC) for NOCAD versus control and OCAD versus NOCAD were 0.840 and 0.830, respectively.

CONCLUSION

Significant retinal microcirculation impairment, while milder than that in OCAD was observed in NOCAD patients, indicating retinal microvasculature assessment might provide a new systemic microcirculation observation window for NOCAD. Furthermore, retinal microvasculature may serve as a new indicator to assess the severity of CAD with good performance of retinal microvascular parameters in identifying different CAD subtypes.

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

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

Acquisition of optical coherence tomography angiography metrics during hemodialysis procedures: A pilot study

BACKGROUND AND AIMS

The observation of optical microcirculation gives us an extraordinary way to directly assess in vivo the responses of human circulation to stress stimuli. We run a pilot study to analyze optical coherence tomography angiography (OCT-A) metrics at determined time-points during a hemodialysis (HD) session to understand how these metrics gradually change and to evaluate possible correlations with patients' characteristics.

METHODS

After the eligibility screening, 15 patients (23 eyes) were included in the study. OCT-A parameters were collected at established time-points: Before treatment (t0), at first hour (t1), at second hour (t2), at third hour (t3), and finally at the end of HD treatment (t4). Patients were finally shared in hypotensive group if they occurred in a hypotensive episode during subsequent month methods or no hypotensive group. The instrument software automatically segmented OCT-A scans into four en-face slabs: The superficial capillary plexus (SCP), the deep capillary plexus (DCP), the outer retinal plexus and the choriocapillaris plexus. In this study we focus on SCP, DCP plexuses.

RESULTS

Overall, the majority of ophthalmic parameters remained unaffected and comparable at dialysis end; a significant reduction being observed at the end vs. starting of HD only for deep capillary plexus (DCP: Whole, fovea, and parafovea) and for central choroid thickness (CCT) (p < 0.05). An overall trend during the session showed in general a decrease with a significance in particular for DCP (whole, fovea, and parafovea) and for CCT (P = 0.006). In the hypotension group, Superficial capillary plexus (SCP: Fovea and parafovea) significantly increased comparing post vs. pre-dialysis values while CCT significantly decreased. Analyzing the trend during treatment only CCT maintained a significant trend (p for trend = 0.002). In the no-hypotension group, neither pre- vs. post-analysis and trend analysis showed a statistical significance.

CONCLUSION

Main achievement of our study was to measure, for the first time in literature, single parameters at different time-points of a HD session. As a result of this process we did not notice a brusque decreasing or increasing of OCT-A metrics but we can characterize the different effect of HD on the two distinct areas distinguishing ocular vessels: Retinal and choroidal circulation. As interesting sub-analysis, Hypotensive group showed for CCT a decreasing trend with a difference statistically significant respect to the group with no-hypotension maintaining a constant trend. In our opinion, these results suggest the role of autonomic system on vessel control in patients affected by uremia.

Subretinal drusenoid deposits are strongly associated with coexistent high-risk vascular diseases

Background/aims

Demonstrate that subretinal drusenoid deposits (SDDs) in age-related macular degeneration (AMD) are linked to coexistent high-risk vascular diseases (HRVDs).

Methods

Cross-sectional study. Two hundred AMD subjects (aged 51–100 years; 121 women, 79 men) were recruited. Spectral domain optical coherence tomography, autofluorescence and near-infrared reflectance imaging, and lipid profiles were obtained. Subjects were assigned by health history questionnaires into those with or without HRVDs, defined as: cardiac valve defect (eg, aortic stenosis), myocardial defect (eg, myocardial infarction) and stroke/transient ischaemic attack. Masked readers assigned subjects into two groups: SDD (with or without drusen) and drusen (only). Univariate testing was performed by χ2test. We built multivariate regression models to test relationships of coexistent HRVD to SDD status, lipid levels and other covariates.

Results

The prevalence of HRVD was 41.2% (40/97) and 6.8% (7/103) in the SDD and non-SDD groups, respectively (correlation of SDD with HRVD, p=9×10−9, OR 9.62, 95% CI 4.04 to 22.91). Multivariate regressions: only SDDs and high-density lipoprotein (HDL) in the first two HDL quartiles remained significant for HRVD (p=9.8×10−5, 0.021, respectively). Multivariate regression model: SDDs and an HDL in Q1 or Q2 identified the presence of HRVD with the accuracy of 78.5%, 95% CI 72.2% to 84.0%.

Conclusions

High-risk cardiovascular and neurovascular diseases were accurately identified in an AMD cohort from SDDs and HDL levels. The SDDs may be related to inadequate ocular perfusion resulting from the systemic vasculopathies. Further research with this paradigm is warranted and might reduce mortality and morbidity from vascular disease.

Retinal and Choroidal Thinning—A Predictor of Coronary Artery Occlusion?

Introduction. Optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) allowed visualization of retina and choroid to nearly the capillary level; however, the relationship between systemic macrovascular status and retinal microvascular changes is not yet known well. Aim. Our purpose was to assess the impact of retinal optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) parameters on prediction of coronary heart disease (CHD) in acute myocardial infarction (MI) and chronic three vessel disease (3VD) groups. Methods. This observational study included 184 patients—26 in 3VD, 76 in MI and 82 in healthy participants groups. Radial scans of the macula and OCTA scans of the central macula (superficial (SCP) and deep (DCP) capillary plexuses) were performed on all participants. All participants underwent coronary angiography. Results. Patients in MI groups showed decreased parafoveal total retinal thickness as well as GCL+ retinal thickness. Outer circle total retinal thickness and GCL+ retinal thickness were lowest in the 3VD group. The MI group had thinner, while 3VD the thinnest, choroid. A decrease in choroidal thickness and vascular density could predict 3VD. Conclusions. A decrease in retinal and choroidal thickness as well as decreased vascular density in the central retinal region may predict coronary artery disease. OCT and OCTA could be a significant, safe, and noninvasive tool for the prediction of coronary artery disease.

Early Diagnosis and Treatment of Coronary Heart Disease with Image Features of Optical Coherence Tomography under Adaptive Segmentation Algorithm

This research was aimed at exploring the application value of optical coherence tomography (OCT) images under adaptive segmentation algorithm in the early diagnosis of coronary heart disease (CHD). Eighty-two patients with CHD were included, who were to undergo coronary angiography (CAG) to confirm their condition. According to the diagnostic criteria of CHD in the American Coronary Artery Surgery Study (CASS), the patients were divided into the stable plaque group (41 cases) and unstable plaque group (41 cases). Besides, 20 healthy volunteers were selected as the control group, and all of them underwent OCT scans. On the basis of a fourth-order partial differential equation (PDE) and active contour (AC) model, a novel adaptive image segmentation algorithm PDE-AC was constructed and used for OCT image processing. No significant difference was found in general clinical data and serological indicators in the control group compared to the other two groups (P > 0.05). The lipid plaque length, degree of stenosis, and lipid pool angle, macrophages and intimal erosion, and plaque fissure in the unstable plaque group were highly greater than those in the stable plaque group. The fibrous cap thickness (FCT) was significantly thinner than that in the stable plaque group (P < 0.05). The diagnostic sensitivity, specificity, and accuracy of OCT under PDE-AC algorithm for CHD (91.53%, 84.08%, and 95.38%) were markedly higher than those of single OCT (83.46%, 75.11%, and 88.02%) (P < 0.05). In summary, OCT images under PDE-AC algorithm did better than simple OCT images in the diagnosis of CHD. Lipid plaque length, degree of stenosis, and lipid pool angle, macrophage and intimal erosion, plaque fissure, and FCT were important indicators for judging plaque stability, having the better clinical application value.

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

OBJECTIVE

To 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).

METHODS

Thirty-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.

RESULTS

The 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).

CONCLUSION

Mild 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.

Choroidal thickness and granulocyte colony-stimulating factor in tears improve the prediction model for coronary artery disease

BACKGROUND

Coronary artery disease (CAD) detection in asymptomatic patients still remains controversial. The aim of our study was to evaluate the usefulness of ophthalmologic findings as predictors of the presence of CAD when added to cardiovascular classic risk factors (CRF) in patients with acute coronary cardiopathy suspicion.

METHODS

After clinical stabilization, 96 patients with acute coronary cardiopathy suspicion were selected and divided in two groups: 69 patients with coronary lesions and 27 patients without coronary lesions. Their 192 eyes were subjected to a complete routine ophthalmologic examination. Samples of tear fluid were also collected to be used in the detection of cytokines and inflammatory mediators. Logistic regression models, receiver operating characteristic curves and their area under the curve (AUC) were analysed.

RESULTS

Suggestive predictors were choroidal thickness (CT) (OR: 1.02, 95% CI 1.01-1.03) and tear granulocyte colony-stimulating factor (G-CSF) (OR: 0.97, 95% CI 0.95-0.99). We obtained an AUC of 0.9646 (95% CI 0.928-0.999) when CT and tear G-CSF were added as independent variables to the logistic regression model with cardiovascular CRF: sex, age, diabetes, high blood pressure, hypercholesterolemia, smoking habit and obesity. This AUC was significantly higher (p = 0.003) than the prediction derived from the same logistic regression model without CT and tear G-CSF (AUC = 0.828, 95% CI 0.729-0.927).

CONCLUSIONS

CT and tear G-CSF improved the predictive model for CAD when added to cardiovascular CRF in our sample of symptomatic patients. Subsequent studies are needed for validation of these findings in asymptomatic patients.

Schizophrenia in Translation: Why the Eye?

Schizophrenia is increasingly recognized as a systemic disease, characterized by dysregulation in multiple physiological systems (eg, neural, cardiovascular, endocrine). Many of these changes are observed as early as the first psychotic episode, and in people at high risk for the disorder. Expanding the search for biomarkers of schizophrenia beyond genes, blood, and brain may allow for inexpensive, noninvasive, and objective markers of diagnosis, phenotype, treatment response, and prognosis. Several anatomic and physiologic aspects of the eye have shown promise as biomarkers of brain health in a range of neurological disorders, and of heart, kidney, endocrine, and other impairments in other medical conditions. In schizophrenia, thinning and volume loss in retinal neural layers have been observed, and are associated with illness progression, brain volume loss, and cognitive impairment. Retinal microvascular changes have also been observed. Abnormal pupil responses and corneal nerve disintegration are related to aspects of brain function and structure in schizophrenia. In addition, studying the eye can inform about emerging cardiovascular, neuroinflammatory, and metabolic diseases in people with early psychosis, and about the causes of several of the visual changes observed in the disorder. Application of the methods of oculomics, or eye-based biomarkers of non-ophthalmological pathology, to the treatment and study of schizophrenia has the potential to provide tools for patient monitoring and data-driven prediction, as well as for clarifying pathophysiology and course of illness. Given their demonstrated utility in neuropsychiatry, we recommend greater adoption of these tools for schizophrenia research and patient care.

Associations between Choriocapillaris Flow on Optical Coherence Tomography Angiography and Cardiovascular Risk Profiles of Patients with Acute Myocardial Infarction

We evaluated the association between macular perfusion assessed via optical coherence tomography angiography (OCTA) and the cardiovascular risk profiles of patients with acute myocardial infarction (AMI). Patients with AMI who underwent comprehensive ophthalmological examinations and retinal OCTA were evaluated retrospectively. Retinal OCTA was performed for each patient within 3 days of admission. Quantitative analyses of the vessel density (VD) of the superficial capillary plexus (SCP) layers, deep capillary plexus layers (DCP), and choriocapillaris were performed after image processing. The 10-year risk of atherosclerotic cardiovascular disease (ASCVD), Global Registry of Acute Coronary Events (GRACE) score, reduction of atherothrombosis for continued health (REACH) score, and thrombolysis in myocardial infarction (TIMI) risk score were assessed. Sixty patients were included. VD in SCP and DCP was not associated with a 10-year ASCVD risk; however, choriocapillaris flow void features were significantly correlated with the 10-year ASCVD risk: decreased count, increased average size, and increased signal void area were correlated with increased 10-year ASCVD risk, GRACE score, REACH score, and TIMI risk score. In the multivariate analysis, a 10-year ASCVD risk (adjusted odds ratio [OR], 1.04; 95% confidence interval [CI], 1.01–1.08) and brain natriuretic peptide (adjusted OR, 1.00; 95% CI, 1.00–1.01) were significantly associated with the highest tertile of the average size of the choriocapillaris. Choriocapillaris flow void features measured using OCTA were associated with cardiovascular risk profiles in patients with AMI. OCTA may be used as an indicator of cardiovascular risk profiles and could improve cardiovascular risk assessments.

Retinal microvascular morphology versus COVID-19: What to anticipate?

BACKGROUND

To investigate retinal microvascular morphological changes in previously COVID-19 infected patients using optical coherence tomography angiography (OCTA), and compare the findings to age- and gender-matched healthy subjects.

METHODS

In this cross-sectional study, OCTA findings (6.0 × 6.0 mm scan size and scan quality index ≥7/10) from previously COVID-19 infected patients (group 1, 32 patients, 64 eyes) with ≥1 month of complete recovery were compared to healthy subjects (group 2, 33 subjects, 66 eyes) with no history of COVID-19 infection. A positive real-time reverse transcription-polymerase chain reaction test on a naso-pharyngeal swab sample confirmed the diagnosis. The AngioVueAnalytics, RTVue-XR 2017.1.0.155 software measured and recorded OCTA parameters.

RESULTS

Group 1 had significantly lower superficial capillary plexus vessel densities in all foveal regions than group 2 (P<0.05). Foveal deep capillary plexus vessel density in group 1 was also significantly lower than in group 2 (P=0.009); however, no significant differences were found in other regions (P>0.05). All foveal avascular zone (FAZ) parameters were higher in group 1 than in group 2, with significant differences in FAZ area (P=0.019) and foveal vessel density 300 μm area around FAZ (P=0.035), but not FAZ perimeter (P=0.054). The outer retina and choriocapillaris flows were significantly lower in group 1 than in group 2 (P<0.05).

CONCLUSIONS

Prior COVID-19 infection seems to be associated with significant changes in retinal microvascular density, as well as FAZ and flow parameters, which may be attributed to different pathogenic mechanisms that lead to SARS-CoV-2 infection, such as thrombotic microangiopathy and angiotensin-converting enzyme 2 disruption.

Development and Validation of Retinal Vasculature Nomogram in Suspected Angina Due to Coronary Artery Disease

AIMS

To develop and validate a nomogram using retinal vasculature features and clinical variables to predict coronary artery disease (CAD) in patients with suspected angina.

METHODS

The prediction model consisting of 795 participants was developed in a training set of 508 participants with suspected angina due to CAD, and data were collected from January 2018 to June 2019. The held-out validation was conducted with 287 consecutive patients from July 2019 to November 2019. All patients with suspected CAD received optical coherence tomography angiography (OCTA) examination before undergoing coronary CT angiography. LASSO regression model was used for data reduction and feature selection. Multivariable logistic regression analysis was used to develop the retinal vasculature model for predicting the probability of the presence of CAD.

RESULTS

Three potential OCTA parameters including vessel density of the nasal and temporal perifovea in the superficial capillary plexus and vessel density of the inferior parafovea in the deep capillary plexus were further selected as independent retinal vasculature predictors. Model clinical electrocardiogram (ECG) OCTA (clinical variables＋ECG＋OCTA) was presented as the individual prediction nomogram, with good discrimination (AUC of 0.942 [95% CI, 0.923-0.961] and 0.897 [95% CI, 0.861-0.933] in the training and held-out validation sets, respectively) and good calibration. Decision curve analysis indicated the clinical applicability of this retinal vasculature nomogram.

CONCLUSIONS

The presented retinal vasculature nomogram based on individual probability can accurately identify the presence of CAD, which could improve patient selection and diagnostic yield of aggressive testing before determining a diagnosis.

Towards standardizing retinal optical coherence tomography angiography: a review

The visualization and assessment of retinal microvasculature are important in the study, diagnosis, monitoring, and guidance of treatment of ocular and systemic diseases. With the introduction of optical coherence tomography angiography (OCTA), it has become possible to visualize the retinal microvasculature volumetrically and without a contrast agent. Many lab-based and commercial clinical instruments, imaging protocols and data analysis methods and metrics, have been applied, often inconsistently, resulting in a confusing picture that represents a major barrier to progress in applying OCTA to reduce the burden of disease. Open data and software sharing, and cross-comparison and pooling of data from different studies are rare. These inabilities have impeded building the large databases of annotated OCTA images of healthy and diseased retinas that are necessary to study and define characteristics of specific conditions. This paper addresses the steps needed to standardize OCTA imaging of the human retina to address these limitations. Through review of the OCTA literature, we identify issues and inconsistencies and propose minimum standards for imaging protocols, data analysis methods, metrics, reporting of findings, and clinical practice and, where this is not possible, we identify areas that require further investigation. We hope that this paper will encourage the unification of imaging protocols in OCTA, promote transparency in the process of data collection, analysis, and reporting, and facilitate increasing the impact of OCTA on retinal healthcare delivery and life science investigations.

Evaluation of subclinical retinal microvascular changes in systemic lupus erythematosus patients using optical coherence tomography angiography and its relationship with disease activity

Objective

This study aimed to investigate subclinical retinal microvascular changes with optical coherence tomography angiography (OCTA) in patients with systemic lupus erythematosus (SLE) and healthy controls (HCs), and to evaluate the relationship between OCTA findings and Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K).

Materials and Methods

In this study, 47 eyes of SLE and 41 eyes of healthy control (HC) were evaluated. The SLE patients were divided into two subgroups: low disease activity (LDA) (SLEDAI≤5) and high disease activity (HDA) (SLEDAI>6). The results of OCTA were compared between SLE patients and HCs as well as the SLE subgroups. The relationship between OCTA results and SLEDAI-2K was evaluated.

Results

There were no differences in foveal avascular zone (FAZ) areas between the SLE patients and HCs. Central foveal thickness (CFT) was lower in SLE patients ( p = .046). Superficial capillary plexus (SCP) vessel density (VD) in SLE patients was significantly lower only in the foveal area compared to that in HCs ( p = .006). Deep capillary plexus (DCP) VD in SLE patients was significantly lower in all areas except the temporal parafoveal area compared to that in the HCs. There was no statistically significant difference between SLE groups with LDA and HDA in FAZ or any of the other areas, including SCP and DCP. When the correlation between OCTA findings and SLEDAI-2K was examined, both SCP and DCP VD were found to be negatively correlated.

conclusions

It was observed that DCP VDs were affected in SLE patients with LDA, and SCP VDs were also affected in addition to DCP with HDA. This suggests that DCP may be the first capillary plexus to be comprised in SLE. VDs were negatively correlated with disease activity. It was concluded that OCTA can be a useful tool in assessing subclinical retinal microvascular pathology and disease activity in patients with SLE.

Relationship of Quantitative Retinal Capillary Network and Myocardial Remodeling in Systemic Hypertension

Background

This study examined the associations between quantitative optical coherence tomography angiography (OCTA) parameters and myocardial abnormalities as documented on cardiovascular magnetic resonance imaging in patients with systemic hypertension.

Methods and Results

We conducted a cross‐sectional study of 118 adults with hypertension (197 eyes). Patients underwent cardiovascular magnetic resonance imaging and OCTA (PLEX Elite 9000, Carl Zeiss Meditec). Associations between OCTA parameters (superficial and deep retinal capillary density) and adverse cardiac remodeling (left ventricular mass, remodeling index, interstitial fibrosis, global longitudinal strain, and presence of left ventricular hypertrophy) were studied using multivariable linear regression analysis with generalized estimating equations. Of the 118 patients with hypertension enrolled (65% men; median [interquartile range] age, 59 [13] years), 29% had left ventricular hypertrophy. After adjusting for age, sex, systolic blood pressure, diabetes, and signal strength of OCTA scans, patients with lower superficial capillary density had significantly higher left ventricular mass (β=−0.150; 95% CI, −0.290 to −0.010), higher interstitial volume (β=−0.270; 95% CI, −0.535 to −0.0015), and worse global longitudinal strain (β=−0.109; 95% CI, −0.187 to −0.032). Lower superficial capillary density was found in patients with hypertension with replacement fibrosis versus no replacement fibrosis (16.53±0.64 mm ‐1 versus 16.96±0.64 mm ‐1 ; P =0.003).

Conclusions

We showed significant correlations between retinal capillary density and adverse cardiac remodeling markers in patients with hypertension, supporting the notion that the OCTA could provide a non‐invasive index of microcirculation alteration for vascular risk stratification in people with hypertension.

Age-Related Macular Degeneration and Cardiovascular Diseases: Revisiting the Common Soil Theory

ABSTRACT

Age-related macular degeneration (AMD), a complex disease associated with aging, remains one of the leading causes of visual loss in high-income countries and its prevalence is expected to increase over the next decades. Polypoidal choroidal vasculopathy has been considered a variant of neovascular AMD and is highly prevalent in Asian populations. Similarly, cardiovascular disease (CVD)-another complex disease associated with aging-is a leading cause of morbidity and mortality in high-income countries and its prevalence is also expected to increase due to population aging. Previous studies reported an increased risk for CVD in AMD patients, indicating an underlying "common soil." Reviewing the current literature, consistent evidence for common risk factors and mutual comorbidity was identified for both diseases. Cardiovascular risk factors include smoking, diet, and low levels of physical activity, which also play a role in AMD pathogenesis. Several studies demonstrated AMD patients to be at higher risk for CVD compared to the general older population. The complexity of both diseases, however, complicates research on their relation, and thus studies ought to be interpreted with caution. Herein we present an overview of selected studies and their main "take-home messages" on this topic, and hypothesize on the patho-etiologic "common ground" of these 2 diseases.

Retinal microvasculature impairments in patients with coronary artery disease: An optical coherence tomography angiography study

PURPOSE

To investigate the association between retinal microvasculature and the presence and severity of coronary artery disease (CAD) using optical coherence tomography angiography (OCTA).

METHODS

The cross-sectional study was conducted in Guangdong Provincial People's Hospital, China. Retinal microvasculature parameters were measured by OCTA of the optic disc, including the vessel density (VD) and retinal nerve fibre thickness of the radial peripapillary capillary. In terms of the entire macula, VD of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and foveal density (FD-300) were included. The Gensini score was used to evaluate the severity of coronary artery obstructive lesions in CAD patients.

RESULTS

A total of 410 participants (270 CAD patients and 140 controls) were included. Overall, participants showed significantly greater odds of having CAD in the lower versus higher VD for mean SCP, OR = 2.33 (95% CI 1.49-3.65); in the parafoveal SCP, OR = 2.68 (95% CI 1.70-4.23); and in the perifoveal SCP, OR = 2.36 (95% CI 1.49-3.72). Additionally, participants showed significantly greater odds of having CAD in the lower versus higher VD for mean DCP, OR = 4.04 (95% CI 2.53-6.45); in the parafoveal DCP, OR = 4.08 (95% CI 2.54-6.55); and in the perifoveal DCP, OR = 3.88 (95% CI 2.43-6.19). Among CAD patients, lower VD of DCP was associated with significantly greater adjusted Gensini scores (p = 0.004 for mean DCP; p = 0.035 for parafoveal DCP; p = 0.006 for perifoveal DCP).

CONCLUSIONS

SCP and DCP were found to be associated with the presence of CAD among the whole population, while DCP was found to be associated with Gensini scores in CAD patients. Retinal microvasculature was associated with the presence and severity of coronary artery stenosis in CAD patients.

Detection of Systemic Diseases From Ocular Images Using Artificial Intelligence: A Systematic Review

PURPOSE

Despite the huge investment in health care, there is still a lack of precise and easily accessible screening systems. With proven associations to many systemic diseases, the eye could potentially provide a credible perspective as a novel screening tool. This systematic review aims to summarize the current applications of ocular image-based artificial intelligence on the detection of systemic diseases and suggest future trends for systemic disease screening.

METHODS

A systematic search was conducted on September 1, 2021, using 3 databases-PubMed, Google Scholar, and Web of Science library. Date restrictions were not imposed and search terms covering ocular images, systemic diseases, and artificial intelligence aspects were used.

RESULTS

Thirty-three papers were included in this systematic review. A spectrum of target diseases was observed, and this included but was not limited to cardio-cerebrovascular diseases, central nervous system diseases, renal dysfunctions, and hepatological diseases. Additionally, one- third of the papers included risk factor predictions for the respective systemic diseases.

CONCLUSIONS

Ocular image - based artificial intelligence possesses potential diagnostic power to screen various systemic diseases and has also demonstrated the ability to detect Alzheimer and chronic kidney diseases at early stages. Further research is needed to validate these models for real-world implementation.

Optical coherence tomography angiography changes in cardiovascular systemic diseases and risk factors: A Review

Cardiovascular (CV) disease (CVD) is the main cause of death around the world, and assessing a patient's CV risk factors (CVRF) can play a major role in its prevention. Since it has been shown that retinal vascular alterations may reflect several systemic processes such as CVRF, we conducted a systematic review in order to summarize which ocular microvasculature changes can be found using Optical Coherence Tomography Angiography (OCTA) in patients without ocular diseases and with systemic pathologies/conditions that affect the CV system when compared to healthy subjects. We searched on online databases, namely PubMed, Scopus, Cochrane and Web of Science, and obtained additional studies through citation tracking. Case reports and review articles were excluded. A total of 47 articles were included in our review. We describe that patients with hypertension, diabetes mellitus, kidney disease, preeclampsia, coronary artery disease, carotid artery stenosis and obstructive sleep apnoea syndrome have, in general, lower retinal and choroidal Vessel Density (VD) and Length (VL), as well as an increased foveal avascular zone area and perimeter. Additionally, several characteristics and/or conditions in healthy subjects, such as smoking status, hyper or hypoxia conditions, race, among others, are also related to ocular vascular changes and should be accounted for. We concluded that OCTA could be a useful tool to assess a patient's CV risk profile in a non-invasive way, possibly integrating the diagnostic and prognostic algorithms of the most prevalent CV diseases in the future.