Risk Factors and Treatment Strategy for Retinal Vascular Occlusive Diseases

Artificial intelligence in therapeutic management of hyperlipidemic ocular pathology

Hyperlipidemia has many ocular manifestations, the most prevalent being retinal vascular occlusion. Hyperlipidemic lesions and occlusions to the vessels supplying the retina result in permanent blindness, necessitating prompt detection and treatment. Retinal vascular occlusion is diagnosed using different imaging modalities, including optical coherence tomography angiography. These diagnostic techniques obtain images representing the blood flow through the retinal vessels, providing an opportunity for AI to utilize image recognition to detect blockages and abnormalities before patients present with symptoms. AI is already being used as a non-invasive method to detect retinal vascular occlusions and other vascular pathology, as well as predict treatment outcomes. As providers see an increase in patients presenting with new retinal vascular occlusions, the use of AI to detect and treat these conditions has the potential to improve patient outcomes and reduce the financial burden on the healthcare system. This article comprehends the implications of AI in the current management strategies of retinal vascular occlusion (RVO) in hyperlipidemia and the recent developments of AI technology in the management of ocular diseases.

Nationwide Incidence and Trends in Central Retinal Arterial Occlusion Management: A 5000-Patient Analysis

Central retinal artery occlusion (CRAO) is a rare and visually debilitating vascular condition characterized by sudden and severe vision loss. CRAO is a compelling target for intravenous alteplase (tPA) and endovascular mechanical thrombectomy (MT) due to pathophysiological similarities with acute ischemic stroke; however, the utility of these interventions in CRAO remains dubious due to limited sample sizes and potential risks. To assess usage and outcomes of tPA and MT in CRAO, we queried the National Inpatient Sample database using International Classification of Disease, Ninth and Tenth edition for patients with CRAO and acute ischemic stroke between 2010 and 2019. Our cohort of 5009 CRAO patients were younger with higher rates of obesity, hypertension, long-term anticoagulant use, and tobacco use compared to acute ischemic stroke patients. CRAO patients had lower rates of tPA administration (3.41% vs 6.21%) and endovascular MT (0.38% vs 1.31%) but fewer complications, including deep vein thrombosis, pneumonia, urinary tract infection, acute kidney injury, and acute myocardial infarction (all P < 0.01). CRAO patients had lower rates of poor functional outcome (31.74% vs 58.1%) and in-hospital mortality (1.2% vs 5.64%), but higher rates of profound blindness (9.24% vs 0.58%). A multivariate regression showed no relationship between tPA and MT and profound blindness, although the limited sample size of patients receiving interventions may have contributed to this apparent insignificance. Further investigation of larger patient cohorts and alternative treatment modalities could provide valuable insights for revascularization therapies in CRAO to optimize visual restoration and clinical outcomes.

Application and progress of artificial intelligence technology in the segmentation of hyperreflective foci in OCT images for ophthalmic disease research

With the advancement of retinal imaging, hyperreflective foci (HRF) on optical coherence tomography (OCT) images have gained significant attention as potential biological biomarkers for retinal neuroinflammation. However, these biomarkers, represented by HRF, present pose challenges in terms of localization, quantification, and require substantial time and resources. In recent years, the progress and utilization of artificial intelligence (AI) have provided powerful tools for the analysis of biological markers. AI technology enables use machine learning (ML), deep learning (DL) and other technologies to precise characterization of changes in biological biomarkers during disease progression and facilitates quantitative assessments. Based on ophthalmic images, AI has significant implications for early screening, diagnostic grading, treatment efficacy evaluation, treatment recommendations, and prognosis development in common ophthalmic diseases. Moreover, it will help reduce the reliance of the healthcare system on human labor, which has the potential to simplify and expedite clinical trials, enhance the reliability and professionalism of disease management, and improve the prediction of adverse events. This article offers a comprehensive review of the application of AI in combination with HRF on OCT images in ophthalmic diseases including age-related macular degeneration (AMD), diabetic macular edema (DME), retinal vein occlusion (RVO) and other retinal diseases and presents prospects for their utilization.

Exploring laser-induced acute and chronic retinal vein occlusion mouse models: Development, temporal in vivo imaging, and application perspectives

Photodynamic venous occlusion is a commonly accepted method for establishing mouse models of retinal vein occlusion (RVO). However, existing model parameters do not distinguish between acute and chronic RVO subtypes. Large variations in laser energy seem to correlate with fluctuating retinopathy severity and high rates of venous recanalization during the acute phase, along with the variable levels of retinal perfusion during the chronic phase. After optimizing the modeling procedure and defining success and exclusion criteria, laser energy groups of 80mW, 100mW, and 120mW were established. Multimodal imaging confirmed that higher energy levels increased the incidence of retinal cystoid edema and intraretinal hemorrhage, exacerbated the severity of exudative retinal detachment, and reduced the venous recanalization rate. For the acute model, 100mW was considered an appropriate parameter for balancing moderate retinopathy and venous recanalization. Continuous imaging follow-up revealed that day 1 after RVO was the optimal observation point for peaking of retinal thickness and intensive occurrence of retinal cystic edema and intraretinal hemorrhage. After excluding the influence of venous recanalization on retinal thickness, acute retinal edema demonstrated a positive response to standard anti-vascular endothelial growth factor therapy, validating the clinical relevance of the acute RVO model for further study in pathogenic mechanisms and therapeutic efficacy. For the chronic model, the 120mW parameter with the lowest venous recanalization rate was applied, accompanied by an increase in both photocoagulation shots and range to ensure sustained vein occlusion. Imaging follow-up clarified non-ischemic retinopathy characterized by tortuosity and dilation of the distal end, branches, and adjacent veins of the occluded vein. These morphological changes are quantifiable and could be combined with electrophysiological functional assessment for treatment effectiveness evaluation. Moreover, the stable state of venous occlusion may facilitate investigations into response and compensation mechanisms under conditions of chronic retinal hypoperfusion.

Advances in Extraction Protocols, Degradation Methods, and Bioactivities of Proanthocyanidins

Proanthocyanidins, natural polyphenolic compounds abundantly present in plants, exhibit diverse bioactivities, including antioxidative, anti-inflammatory, and antibacterial effects. These bioactivities are intricately linked to the degree of polymerization of these compounds. Through a comprehensive analysis of recent domestic and international research, this article synthesizes the latest advancements in the extraction process, degradation methods, as well as the biological activities and underlying mechanisms of proanthocyanidins. Furthermore, future research endeavors should prioritize the refinement of extraction techniques, the elucidation of bioactive mechanisms, and the development of formulations with enhanced potency. This will maximize the utilization of proanthocyanidins across diverse applications.

Pediatric Central Retinal Artery Occlusion Attributed to a Patent Ductus Arteriosus

This report presents a rare case of a central retinal artery occlusion in an eight-year-old girl attributed to an undiagnosed patent ductus arteriosus (PDA). Despite intensive treatment, the patient's eyesight failed to improve. Cases of central retinal artery occlusion may occur in patients with undiagnosed, small PDA, with only symptomatic treatment being available.

Long-Term Outcomes in Early versus Limited Response to Anti-VEGF Treatment for Retinal Vein Occlusion

OBJECTIVE

Macular edema secondary to retinal vein occlusion (RVO) is a sight-threatening condition. Previous studies showed that early responders (ERs) who respond well to anti-VEGF injections within 3 months of treatment have better outcomes, as measured by best visual acuity (BVA) and central subfield thickness (CST) at 12 months postinjection initiation compared with limited early responders (LERs). This study analyzed whether ER eyes continue to respond better than LER eyes over longer periods. This study also aimed to identify baseline comorbidities associated with response status.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients aged > 18 years with RVO-related macular edema treated with anti-VEGF injections.

METHODS

Patients were categorized as ERs or LERs. Limited early responder eyes were defined as having CST reduction < 10%, BVA gain < 5 ETDRS letters, or both at 3 months after anti-VEGF initiation. Best visual acuity and CST changes over the 24- and 36-month period after the first anti-VEGF treatment were compared between ERs and LERs. Patient characteristics and systemic comorbidities were identified by chart review. Statistical analysis involved the Levene test, Welch t test, and Welch analysis of variance.

MAIN OUTCOME MEASURES

Best visual acuity and CST changes over the initial 24-month and 36-month periods after treatment.

RESULTS

The 24-month cohort included 68 ERs and 39 LERs, and the 36-month cohort included 58 ERs and 33 LERs. At the 24-month time point, there were significant differences in BVA and CST gains between ERs (+19.8 letters, -221.2 um) and LERs (-2.4 letters, -90.1 um; P < 0.001, P < 0.01). Similarly, at 36 months, there were significant differences in BVA and CST gains between ERs (+17.7 letters, -229.3 um) and LERs (+1.3 letters, -128 um; P < 0.001, P < 0.05). After controlling for differences in baseline BVA and CST, only the 24-month change in BVA remained significant (P < 0.001). There were no significant associations between response status and cardiopulmonary, endocrine, and oncologic comorbidities.

CONCLUSIONS

Early responder eyes with branched retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) have better functional responses to anti-VEGF injections at 24 months compared with LER eyes, even after controlling for baseline differences. Early identification of eyes as ERs or LERs in BRVO and CRVO may predict long-term functional prognoses.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Outcomes of vitrectomy, complete pan-retinal photocoagulation, and endoscopic cyclophotocoagulation surgery after anti-VEGF treatment in neovascular glaucoma

Purpose

To establish a comprehensive treatment strategy and evaluate the efficacy of combination of anti-vascular endothelial growth factor (VEGF) injection, pars plana vitrectomy (PPV), endoscopic pan-retinal photocoagulation (PRP), and endoscopic cyclophotocoagulation (ECP) surgery for neovascular glaucoma (NVG) patients.

Methods

This retrospective study included 30 patients (30 eyes) who were suffering from NVG and treated with PPV & PRP & ECP (ECP group, 16 eyes), or Ahmed glaucoma valve implantation (Ahmed group, 14 eyes). The intraocular pressure (IOP), number of postoperative anti-glaucoma medications, best-corrected visual acuity (BCVA), successful rate of surgery, and postoperative complications were recorded and statistically analyzed at the time points of preoperative, 1-day, 1-month, 3-months, 6-months, and 12-months after operation.

Results

An obvious reduction in IOP and number of postoperative anti-glaucoma medications were observed in both the ECP group and Ahmed group after operation (P ​< ​0.05), and the ECP group showed a significantly lower IOP compared to the Ahmed group at the 6-months (P ​= ​0.014) and 12-months (P ​= ​0.047) postoperative time points, while there was no significant difference of medication number between the two groups except for 1-day after surgery. The BCVA showed no marked difference between the two groups preoperatively and postoperatively (P ​> ​0.05), while it was significantly improved in ECP group at 3-months (P ​= ​0.001), 6-months (P ​= ​0.004), and 12-months (P ​= ​0.010) time points comparing with preoperative BCVA. The surgical success rates in ECP group were also slightly higher than Ahmed group. And the complications after operation showed no marked differences.

Conclusions

The comprehensive treatment of PPV, endoscopic PRP, and ECP surgery for NVG patients after anti-VEGF injection can control IOP effectively and be friendly to patients' BCVA without obvious serious complications throughout a 12-months follow-up period.

High prevalence of thrombophilic risk factors in patients with central retinal artery occlusion

INTRODUCTION

Central retinal artery occlusion (CRAO) is a common cause of blindness and visual morbidity. In the majority of cases, it is related to thrombotic embolism. Nevertheless, the role of inherited or acquired thrombophilic risk factors in CRAO pathogenesis has not been comprehensively studied.

METHODS

In 126 CRAO patients (66 [52.4%] men, median age 55 [range: 18-80] years) and 107 matched controls (56 [52.3%] men, median age 53 [range: 34-78] years) we evaluated classical atherosclerotic risk factors, including serum lipid profile and glucose level, analyzed intima-media complex thickness (IMT) of external carotid arteries, and performed transthoracic echocardiography. Furthermore, we established the prevalence of inherited and acquired thrombophilic risk factors, such as factor V Leiden (FVL) and prothrombin 20210 G/A genetic variants, plasma activity of factor (F) VIII, protein C and antithrombin activity, and free protein S levels. We also assessed the presence of antiphospholipid antibodies (APLA) and evaluated blood homocysteine in all enrolled subjects. Additionally, we estimated the occurrence of Val34Leu polymorphism of the A subunit of coagulation factor XIII (FXIII-A) in both groups as a potential thrombosis-protecting factor.

RESULTS

Among traditional atherosclerotic risk components, obesity/overweight and hypercholesterolemia were the most common in the CRAO group and occurred in 103 (81.7%) and 85 (67.5%) patients, respectively. CRAO patients also had elevated IMT and altered echocardiographic parameters, indicating diastolic cardiac dysfunction. In thrombophilia investigations, at least one laboratory risk factor occurred in 72.2% (n = 91) of CRAO patients, with APLA as the most frequent, detected in 38.1% (n = 48) of them (almost seven times more frequent than in controls, p < 0.001). Deficiencies in protein C activity and free protein S levels were also common in the CRAO group, reported in 17.5% (n = 22) and 19.8% (n = 25) of patients, respectively. Interestingly, among two analyzed prothrombotic genetic variants, only the FVL was related to CRAO, with the allelic frequency 2.4 times more prevalent than in controls (p = 0.044). Finally, the CRAO group was characterized by hyperhomocysteinemia, almost twice as common as in controls (p = 0.026). Antithrombin deficiency, elevated FVIII, and FXIII-A Val34Leu polymorphism were not associated with CRAO.

CONCLUSIONS

Our findings suggest that thrombophilia plays a vital role in the pathogenesis of CRAO. Thus, proper laboratory screening should be considered in the primary and secondary prevention of those episodes, with implementing appropriate therapy as needed.

Analyze of factors and prognosis of eyes lost to follow-up in retinal vein occlusive disease patients receiving anti-vascular endothelial growth factor therapy

BACKGROUND

Patients with macular edema (ME) secondary to retinal vein occlusion (RVO) who received at least one intravitreal injection of anti-vascular endothelial growth factor therapy (VEGF) and lost to follow-up (LTFU) for more than six months were analyzed to investigate the factors contributing to the LTFU and the prognosis.

METHOD

This was a retrospective, single-center study to analyze the causes and prognosis of LTFU over six months in RVO-ME patients treated with intravitreal anti-VEGF injections at our institution from January 2019 to August 2022 and to collect patients' baseline characteristics along with the number of injections before LTFU, primary disease, best corrected visual acuity (BCVA) before LTFU and after return visit, central macular thickness (CMT), months before LTFU and after LTFU, reasons for LTFU, and complications, to analyze the factors affecting visual outcome at a return visit.

RESULTS

This study included 125 patients with LTFU; 103 remained LTFU after six months, and 22 returned after LTFU. The common reason for LTFU was "no improvement in vision" (34.4%), followed by "transport inconvenience" (22.4%), 16 patients (12.8%) were unwilling to visit the clinic, 15 patients (12.0%) had already elected to seek treatment elsewhere, 12 patients (9.6%) were not seen in time due to the 2019-nCov epidemic, and 11 patients (8.8%) cannot do it due to financial reasons. The number of injections before LTFU was a risk factor for LTFU (P < 0.05). LogMAR at the initial visit (P < 0.001), CMT at the initial visit (P < 0.05), CMT before the LTFU (P < 0.001), and CMT after the return visit (P < 0.05) were influential factors for logMAR at the return visit.

CONCLUSION

Most RVO-ME patients were LTFU after anti-VEGF therapy. Long-term LTFU is greatly detrimental to the visual quality of patients; thus, the management of RVO-ME patients in follow-up should be considered.

Mendelian randomization indicates a causal contribution of type 2 diabetes to retinal vein occlusion

Background

Retinal vein occlusion (RVO) is a common retinal vascular disease that can cause severe visual impairment. Many observational studies have shown that type 2 diabetes (T2DM) is associated with RVO, but it remains unknown if the association is causal. The present study aimed to perform Mendelian randomization (MR) analyses to evaluate the causal contribution of genetically predicted T2DM to RVO.

Methods

We obtained summary-level data from a genome-wide association study meta-analysis including 48,286 cases and 250,671 controls for T2DM and from a genome wide association study of 372 cases and 182,573 controls in the FinnGen project for RVO. To verify the robustness of the results, an independent validation dataset for T2DM (12,931 cases and 57,196 controls) was used. In addition to the main MR analysis using the inverse variance weighted (fixed effect) approach, sensitivity analyses and multivariable MR adjusting for common risk factors of RVO were conducted.

Results

Genetically predicted T2DM was found to be causally associated with RVO risk (odds ratio (OR)=2.823, 95% confidence interval (CI): 2.072-3.847, P=4.868×10^-11). This association was supported by sensitivity analyses using the weighted median (OR=2.415, 95% CI: 1.411-4.132, P=1.294×10^-3), weighted mode (OR=2.370, 95% CI: 1.321-4.252, P=5.159×10^-3), maximum likelihood (OR=2.871, 95% CI: 2.100-3.924, P=3.719×10^-11), MR-PRESSO (OR=2.823, 95% CI: 2.135-3.733, P=5.150×10^-10), and MR-Egger (OR=2.441, 95% CI: 1.149-5.184, P=2.335×10^-2) methods. In addition, this association persisted in multivariable MR after accounting for common RVO risk factors (OR=1.748, 95% CI: 1.238-2.467, P=1.490×10^-3). The MR analyses using the validation dataset obtained consistent results.

Conclusion

This study indicates that genetically predicted T2DM may have a causal contribution to RVO. Future studies are required to elucidate the underlying mechanisms.

Research progress on diagnosing retinal vascular diseases based on artificial intelligence and fundus images

As the only blood vessels that can directly be seen in the whole body, pathological changes in retinal vessels are related to the metabolic state of the whole body and many systems, which seriously affect the vision and quality of life of patients. Timely diagnosis and treatment are key to improving vision prognosis. In recent years, with the rapid development of artificial intelligence, the application of artificial intelligence in ophthalmology has become increasingly extensive and in-depth, especially in the field of retinal vascular diseases. Research study results based on artificial intelligence and fundus images are remarkable and provides a great possibility for early diagnosis and treatment. This paper reviews the recent research progress on artificial intelligence in retinal vascular diseases (including diabetic retinopathy, hypertensive retinopathy, retinal vein occlusion, retinopathy of prematurity, and age-related macular degeneration). The limitations and challenges of the research process are also discussed.