Diabetic retinopathy - ocular complications of diabetes mellitus

MediDRNet: Tackling category imbalance in diabetic retinopathy classification with dual-branch learning and prototypical contrastive learning

BACKGROUND AND OBJECTIVE

The classification of diabetic retinopathy (DR) aims to utilize the implicit information in images for early diagnosis, to prevent and mitigate the further worsening of the condition. However, existing methods are often limited by the need to operate within large, annotated datasets to show significant advantages. Additionally, the number of samples for different categories within the dataset needs to be evenly distributed, because the characteristic of sample imbalance distribution can lead to an excessive focus on high-frequency disease categories, while neglecting the less common but equally important disease categories. Therefore, there is an urgent need to develop a new classification method that can effectively alleviate the issue of sample distribution imbalance, thereby enhancing the accuracy of diabetic retinopathy classification.

METHODS

In this work, we propose MediDRNet, a dual-branch network model based on prototypical contrastive learning. This model adopts prototype contrastive learning, creating prototypes for different levels of lesions, ensuring they represent the core features of each lesion level. It classifies by comparing the similarity between data points and their category prototypes. Our dual-branch network structure effectively resolves the issue of category imbalance and improves classification accuracy by emphasizing subtle differences in retinal lesions. Moreover, our approach combines a dual-branch network with specific lesion-level prototypes for core feature representation and incorporates the convolutional block attention module for enhanced lesion feature identification.

RESULTS

Our experiments using both the Kaggle and UWF classification datasets have demonstrated that MediDRNet exhibits exceptional performance compared to other advanced models in the industry, especially on the UWF DR classification dataset where it achieved state-of-the-art performance across all metrics. On the Kaggle DR classification dataset, it achieved the highest average classification accuracy (0.6327) and Macro-F1 score (0.6361). Particularly in the classification tasks for minority categories of diabetic retinopathy on the Kaggle dataset (Grades 1, 2, 3, and 4), the model reached high classification accuracies of 58.08%, 55.32%, 69.73%, and 90.21%, respectively. In the ablation study, the MediDRNet model proved to be more effective in feature extraction from diabetic retinal fundus images compared to other feature extraction methods.

CONCLUSIONS

This study employed prototype contrastive learning and bidirectional branch learning strategies, successfully constructing a grading system for diabetic retinopathy lesions within imbalanced diabetic retinopathy datasets. Through a dual-branch network, the feature learning branch effectively facilitated a smooth transition of features from the grading network to the classification learning branch, accurately identifying minority sample categories. This method not only effectively resolved the issue of sample imbalance but also provided strong support for the precise grading and early diagnosis of diabetic retinopathy in clinical applications, showcasing exceptional performance in handling complex diabetic retinopathy datasets. Moreover, this research significantly improved the efficiency of prevention and management of disease progression in diabetic retinopathy patients within medical practice. We encourage the use and modification of our code, which is publicly accessible on GitHub: https://github.com/ReinforceLove/MediDRNet.

Serum neopterin and orexin-A levels in different stages of diabetic retinopathy

CLINICAL RELEVANCE

Retinopathy is one of the most common microvascular complications of diabetes mellitus and is the leading cause of vision loss in the working middle-aged population.

BACKGROUND

This study aimed to investigate the value of neopterin and orexin-A levels in patients with diabetes mellitus with different stages of diabetic retinopathy and without diabetic retinopathy and to compare those findings with results from healthy individuals without diabetes mellitus.

METHODS

In total, 65 patients with type 2 diabetes mellitus and 22 healthy individuals without diabetes mellitus were enrolled in this prospective study. The participants were separated into four subgroups. The first subgroup included 25 patients without diabetic retinopathy, the second subgroup included 20 patients non-proliferative diabetic retinopathy, the third subgroup included 20 patients with proliferative diabetic retinopathy, and the fourth subgroup included 22 healthy individuals without diabetes mellitus as controls. Serum neopterin and orexin-A levels were analysed and compared among the groups.

RESULTS

The age and gender of the participants between the four subgroups were not statistically significantly different (p > 0.05). The mean neopterin levels were significantly higher in patients included in the diabetes mellitus subgroups compared with the controls (p < 0.001). Neopterin levels significantly increased as diabetic retinopathy progressed within the diabetes mellitus subgroups. Mean orexin-A levels were significantly lower in the diabetes mellitus subgroups compared with the controls (p < 0.001); however, orexin-A levels were not significantly different within the diabetes mellitus subgroups (p > 0.05).

CONCLUSION

Patients with diabetes mellitus have higher serum neopterin and lower serum orexin-A levels compared with healthy individuals without diabetes mellitus. Moreover, serum neopterin levels increase with progression of diabetic retinopathy.

Comprehensive insights into a decade-long journey: The evolution, impact, and human factors of an asynchronous telemedicine program for diabetic retinopathy screening in Pennsylvania, United States

Diabetic Retinopathy stands as a leading cause of irreversible blindness, necessitating frequent examinations, especially in the early stages where effective treatments are available. However, current examination rates vary widely, ranging from 25-60%. This study scrutinizes the Point-of-Care Diabetic Retinopathy Examination Program at the University of Pittsburgh/UPMC, delving into its composition, evolution, challenges, solutions, and improvement opportunities. Employing a narrative approach, insights are gathered from key stakeholders, including ophthalmologists and staff from primary care clinics. A quantitative analysis from 2008 to 2020 provides a comprehensive overview of program outcomes, covering 94 primary care offices with 51 retinal cameras. Program components feature automated non-mydriatic 45° retinal cameras, a dedicated coordinator, rigorous training, and standardized workflows. Over this period, the program conducted 21,960 exams in 16,458 unique individuals, revealing a diverse population with an average age of 58.5 and a balanced gender distribution. Average body mass index (33.96±8.02 kg/m2) and hemoglobin A1c (7.58%±1.88%) surpassed normal ranges, indicating prevalent risk factors for diabetes-related complications. Notably, 24.2% of patients underwent more than one exam, emphasizing program engagement. Findings indicated that 86.3% of exams were gradable, with 59.0% within normal limits, 12.1% showing some evidence of diabetic retinopathy, and 6.4% exhibiting vision-threatening diabetic retinopathy. Follow-up appointments with ophthalmologists were recommended in 31.5% of exams due to indeterminate results, positive diabetic retinopathy (≥moderate or macular exudate), or other findings like age-related macular degeneration or suspected glaucoma. The program demonstrated high reproducibility across diverse healthcare settings, featuring a sustainable model with minimal camera downtime, standardized workflows, and financial support from grants, health systems, and clinical revenues. Despite COVID-19 pandemic challenges, this research emphasizes the program's reproducibility, user-friendly evolution, and promising outcomes. Beyond technical contributions, it highlights human factors influencing program success. Future research could explore adherence to follow-up ophthalmological recommendations and its associated factors.

Mechanistic and therapeutic perspectives of non-coding RNA-modulated apoptotic signaling in diabetic retinopathy

Diabetic retinopathy (DR), a significant and vision-endangering complication associated with diabetes mellitus, constitutes a substantial portion of acquired instances of preventable blindness. The progression of DR appears to prominently feature the loss of retinal cells, encompassing neural retinal cells, pericytes, and endothelial cells. Therefore, mitigating the apoptosis of retinal cells in DR could potentially enhance the therapeutic approach for managing the condition by suppressing retinal vascular leakage. Recent advancements have highlighted the crucial regulatory roles played by non-coding RNAs (ncRNAs) in diverse biological processes. Recent advancements have highlighted that non-coding RNAs (ncRNAs), including microRNAs (miRNAs), circular RNAs (circRNAs), and long non-coding RNAs (lncRNAs), act as central regulators in a wide array of biogenesis and biological functions, exerting control over gene expression associated with histogenesis and cellular differentiation within ocular tissues. Abnormal expression and activity of ncRNAs has been linked to the regulation of diverse cellular functions such as apoptosis, and proliferation. This implies a potential involvement of ncRNAs in the development of DR. Notably, ncRNAs and apoptosis exhibit reciprocal regulatory interactions, jointly influencing the destiny of retinal cells. Consequently, a thorough investigation into the complex relationship between apoptosis and ncRNAs is crucial for developing effective therapeutic and preventative strategies for DR. This review provides a fundamental comprehension of the apoptotic signaling pathways associated with DR. It then delves into the mutual relationship between apoptosis and ncRNAs in the context of DR pathogenesis. This study advances our understanding of the pathophysiology of DR and paves the way for the development of novel therapeutic strategies.

ROBIN: a randomised, double-masked, placebo-controlled Phase IIa study of the AOC3 inhibitor BI 1467335 in diabetic retinopathy

OBJECTIVE

To evaluate the safety and efficacy of BI 1467335 in patients with non-proliferative diabetic retinopathy (NPDR).

METHODS

ROBIN is a Phase IIa, double-masked, randomised, placebo-controlled study (NCT03238963). Patients with NPDR and without centre-involved diabetic macular oedema were included; all had a best corrected visual acuity letter score of ≥70 Early Treatment Diabetic Retinopathy Study letters in the study eye at screening. Patients received oral BI 1467335 10 mg or placebo once daily for 12 weeks. Post-treatment follow-up was 12 weeks. The primary endpoint was the proportion of patients over the 24 weeks with ocular adverse events (AEs). Secondary endpoints were the proportion of patients with ≥2-step improvement from baseline in DRSS severity level at Week 12 and the proportion of patients with non-ocular AEs at 24 weeks.

RESULTS

Seventy-nine patients entered the study (BI 1467335, n = 40; placebo, n = 39). The proportion of patients with ocular AEs over 24 weeks was greater in the BI 1467335 versus the placebo group (35.0% vs 23.1%, respectively). Treatment-related AEs were reported for similar numbers of patients in the placebo and BI 1467335 group (7.7% vs 7.5%, respectively). At Week 12, 5.7% (n = 2) of patients in the BI 1467335 group had a 2-step improvement in DRSS severity level from baseline, compared with 0% in the placebo group.

CONCLUSIONS

BI 1467335 was well tolerated by patients with NPDR. There was a high variability in DRSS levels for individual patients over time, with no clear efficacy signal.

Prevalence and risk factors for diabetic retinopathy at diagnosis of type 2 diabetes: an observational study of 77 681 patients from the Swedish National Diabetes Registry

INTRODUCTION

To assess the prevalence of diabetic retinopathy (DR) in persons with newly diagnosed type 2 diabetes (T2D) to understand the potential need for intensified screening for early detection of T2D.

RESEARCH DESIGN AND METHODS

Individuals from the Swedish National Diabetes Registry with a retinal photo <2 years after diagnosis of T2D were included. The proportion of patients with retinopathy (simplex or worse) was assessed. Patient characteristics and risk factors at diagnosis were analyzed in relation to DR with logistic regression.

RESULTS

In total, 77 681 individuals with newly diagnosed T2D, mean age 62.6 years, 41.1% females were included. Of these, 13 329 (17.2%) had DR.DR was more common in older persons (adjusted OR 1.03 per 10-year increase, 95% CI 1.01 to 1.05) and men compared with women, OR 1.10 (1.05 to 1.14). Other variables associated with DR were OR (95% CI): lower education 1.08 (1.02 to 1.14); previous stroke 1.18 (1.07 to 1.30); chronic kidney disease 1.29 (1.07 to 1.56); treatment with acetylsalicylic acid 1.14 (1.07 to 1.21); ACE inhibitors 1.12 (1.05 to 1.19); and alpha blockers 1.41 (1.15 to 1.73). DR was more common in individuals born in Asia (OR 1.16, 95% CI 1.08 to 1.25) and European countries other than those born in Sweden (OR 1.11, 95% CI 1.05 to 1.18).

CONCLUSIONS

Intensified focus on screening of T2D may be needed in Sweden in clinical practice since nearly one-fifth of persons have retinopathy at diagnosis of T2D. The prevalence of DR was higher in men, birthplace outside of Sweden, and those with a history of stroke, kidney disease, and hypertension.

A mechanistic review on growing multiple therapeutic applications of lutein and its global market research

Lutein is a naturally occurring carotenoid synthesized by plants and algae that has a beneficial effect on several biological processes and associated ailments. Its immediate application is in ophthalmology, where it significantly lowers the incidences of age-related macular degeneration (AMD). It also has anti-inflammatory action, treatment of diabetic retinopathy, and cataracts, and enhancement of visual contrast. To critically assess lutein biosynthesis, therapeutic applicability, and market research literature. We have discussed its theoretical frameworks, experimental evidence, limitations, as well as clinical trial results, and future research prospects. The literature for this review article was mined and compiled by collecting and analyzing articles from several databases, including ScienceDirect, Google Scholar, PubMed, Wiley Online Library, Patentscope, and ClinicalTrials.gov published until March 30, 2022. Patent publications were identified using the search terms like IC:(C07C67/56) AND EN_AB:(lutein) OR EN_TI:(lutein) OR EN_AB:(extraction) OR EN_TI:(process). According to the literature, lutein is an essential nutrient given that it cannot be synthesized in the human body and acts as an antioxidant, affecting AMD, diabetic retinopathy, Rheumatic diseases, inflammation, and cancer. Due to inadequate production and laborious extraction, lutein is expensive despite its high demand and applicability. Market research predicts a 6.3% compound annual growth rate for lutein by 2032. Optimizing lutein extraction for high yield and purity is necessary. Lutein has proven applicability in various ailments as well as cosmetics that can be developed as a candidate drug for various diseases discussed in the review.

Optical coherence tomography angiography macular biomarkers of peripheral retinal ischemia in diabetic macular edema: secondary endpoints from the clinical study "FOVEA"

PURPOSE

To investigate the relationship between the macular values of fractal dimension (FD) and lacunarity (LAC) on optical coherence tomography angiography (OCTA) images and the presence of peripheral retina non-perfusion areas (NPAs) on fluorescein angiography (FA) in patients with treatment-naïve diabetic macular edema (DME).

METHODS

Fifty patients with treatment-naïve DME underwent a full ophthalmic examination, including best-corrected visual acuity measurement, FA, spectral-domain optical coherence tomography, and OCTA. Specifically, FA was performed to detect the presence of retinal NPAs, whereas fractal OCTA analysis was used to determine macular FD and LAC values at the level of the superficial and deep capillary plexus (SCP and DCP). FA montage frames of the posterior pole and peripheral retina, as well as macular OCTA slabs of the SCP and DCP, were obtained.

RESULTS

Thirty (60%) eyes with FA evidence of peripheral retinal NPAs in at least one quadrant showed significantly lower FD and higher LAC in both SCP and DCP, when compared with eyes presenting a well-perfused peripheral retina. Furthermore, macular FD and LAC values were found to be significantly associated with the extent of retinal NPAs.

CONCLUSIONS

Macular FD and LAC of both SCP and DCP seem to be strongly associated with the extent of peripheral retinal NPAs, thus suggesting that may be useful predictive biomarkers of peripheral ischemia in treatment-naïve DME eyes.

Reduced light exposure mitigates streptozotocin-induced vascular changes and gliosis in diabetic retina by an anti-inflammatory effect and increased retinal cholesterol turnover

Diabetic retinopathy is not cured efficiently and changes of lifestyle measures may delay early retinal injury in diabetes. The aim of our study was to investigate the effects of reduced daily light exposure on retinal vascular changes in streptozotocin (STZ)-induced model of DM with emphasis on inflammation, Aqp4 expression, visual cycle and cholesterol metabolism-related gene expression in rat retina and RPE. Male Wistar rats were divided into the following groups: 1. control; 2. diabetic group (DM) treated with streptozotocin (100 mg/kg); 3. group exposed to light/dark cycle 6/18 h (6/18); 4. diabetic group exposed to light/dark cycle 6/18 h (DM+6/18). Retinal vascular abnormalities were estimated based on lectin staining, while the expression of genes involved in the visual cycle, cholesterol metabolism, and inflammation was determined by qRT-PCR. Reduced light exposure alleviated vasculopathy, gliosis and the expression of IL-1 and TNF-α in the retina with increased perivascular Aqp4 expression. The expression of genes involved in visual cycle and cholesterol metabolism was significantly up-regulated in RPE in DM+6/18 vs. DM group. In the retina only the expression of APOE was significantly higher in DM+6/18 vs. DM group. Reduced light exposure mitigates vascular changes and gliosis in DM via its anti-inflammatory effect, increased retinal cholesterol turnover and perivascular Aqp4 expression.

Macrophage activation contributes to diabetic retinopathy

Diabetic retinopathy (DR) is recognized as a neurovascular complication of diabetes, and emerging evidence underscores the pivotal role of inflammation in its pathophysiology. Macrophage activation is increasingly acknowledged as a key contributor to the onset and progression of DR. Different populations of macrophages originating from distinct sources contribute to DR-associated inflammation. Retinal macrophages can be broadly categorized into two main groups based on their origin: intrinsic macrophages situated within the retina and vitreoretinal interface and macrophages derived from infiltrating monocytes. The former comprises microglia (MG), perivascular macrophages, and macrophage-like hyalocytes. Retinal MG, as the principal population of tissue-resident population of mononuclear phagocytes, exhibits high heterogeneity and plasticity while serving as a crucial connector between retinal capillaries and synapses. This makes MG actively involved in the pathological processes across various stages of DR. Activated hyalocytes also contribute to the pathological progression of advanced DR. Additionally, recruited monocytes, displaying rapid turnover in circulation, augment the population of retinal macrophages during DR pathogenesis, exerting pathogenic or protective effect based on different subtypes. In this review, we examine novel perspectives on macrophage biology based on recent studies elucidating the diversity of macrophage identity and function, as well as the mechanisms influencing macrophage behavior. These insights may pave the way for innovative therapeutic strategies in the management of DR.

Mesenchymal Stem Cells Regulate Microglial Polarization via Inhibition of the HMGB1/TLR4 Signaling Pathway in Diabetic Retinopathy

Diabetic retinopathy (DR) is recognized as the most prevalent retinal degenerative disorder. Inflammatory response usually precedes microvascular alteration and is the primary factor of diabetic retinopathy. Activated microglia express many pro-inflammatory cytokines that exacerbate retina inflammation and disruption. In the present study, we found that MSCs alleviated blood-retina barrier (BRB) breakdown in diabetic rats, as evidenced by reduced retinal edema, decreased vascular leakage, and increased occludin expression. The MSC-treated retinal microglia exhibited reduced expression of M1-phenotype markers in the diabetic rats, including inducible nitric oxide synthase (iNOS), CD16, and pro-inflammatory cytokines. On the other hand, MSCs increased the expression of M2-phenotype markers, such as arginase-1 (Arg-1), CD206, and anti-inflammatory cytokines. HMGB1/TLR4 signaling pathway is activated in DR and inhibited after MSC treatment. Consistent with in vivo evidence, MSCs drove BV2 microglia toward M2 phenotype in vitro. Overexpression of HMGB1 in microglia reversed the effects of MSC treatment, suggesting HMGB1/TLR4 pathway is necessary for MSCs' regulatory effects on microglia polarization. Collectively, MSCs exert beneficial effects on DR by polarizing microglia from M1 toward M2 phenotype via inhibiting the HMGB1/TLR4 signaling pathway.

Clinical Characteristics and Surgical Outcomes of Patients Undergoing Pars Plana Vitrectomy for Proliferative Diabetic Retinopathy

OBJECTIVE

To evaluate clinical characteristics impacting surgical outcomes of patients undergoing pars plana vitrectomy (PPV) for complications of proliferative diabetic retinopathy (PDR).

DESIGN

Retrospective consecutive observational case series of patients at a large county hospital in Dallas, Texas, from 2014 to 2019.

SUBJECTS

Seven hundred thirty-two patients (933 eyes) undergoing PPV for PDR complications.

METHODS

Collected data included demographics, surgical indication, adjuvant therapies, intraoperative course, complications, and best corrected visual acuity (BCVA). Patients with < 6 months of follow-up were excluded. Best corrected visual acuity was converted to logarithm of the minimum angle of resolution for analysis. Statistics performed included t test, analysis of variance, and multivariate analyses.

MAIN OUTCOME MEASURES

Postoperative BCVA, primary anatomic success rate, and postoperative complications.

RESULTS

Three hundred ninety-three patients were male (509 eyes; 54.5%) with an average age of 52 years. Postoperative BCVA at 6 months was significantly different among surgical indications: 0.79 versus 0.77 versus 1.20 (P < 0.0001) for vitreous hemorrhage (VH), vitreomacular interface abnormalities, and tractional retinal detachment (TRD), respectively. Adjuvant preoperative therapy with panretinal photocoagulation (PRP) versus no PRP (0.95 vs. 1.25; P < 0.001) and insulin versus no insulin (0.99 vs. 1.17; P < 0.01) were associated with improved vision. Iatrogenic breaks were associated with decreased postoperative vision (1.40 vs. 0.88; P < 0.001). The primary anatomic success rate for TRD was 85% (495 eyes). Combined TRD/RRD (tractional and rhegmatogenous retinal detachment) was associated with a lower success rate compared with macula-on/macula-off TRD, with odds ratios of 0.36, 0.46, and 0.53, respectively. Patients experiencing recurrent detachment postsurgery had worse preoperative visual acuity (VA) (1.93 vs. 1.63; P < 0.01) and were younger (47.6 vs. 50.0; P = 0.02). Postoperative complications occurred in 699 eyes (75%), with VH (498 eyes, 53%), cataract (465, 50%), and elevated intraocular pressure (149, 16%) being the most common. Two hundred thirty-six eyes (25%) required a second PPV operation. Endophthalmitis (1 eye; <1%) and choroidal detachment (5 eyes; <1%) were rare.

CONCLUSIONS

In this retrospective series analyzing surgical outcomes among patients with complications from PDR, vitrectomy led to improved vision on average, with a meaningful proportion of patients receiving additional surgical intervention. Surgical indication, presenting VA, age, and adjuvant therapies appeared to impact outcomes.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Nifuroxazide repurposing for protection from diabetes-induced retinal injury in rats: Implication of oxidative stress and JAK/STAT3 axis

The prevalence of diabetes mellitus (DM) is alarmingly increasing worldwide. Diabetic retinopathy (DR) is a prevailing DM microvascular complication, representing the major cause of blindness in working-age population. Inflammation is a crucial player in DR pathogenesis. JAK/STAT3 axis is a pleotropic cascade that modulates diverse inflammatory events. Nifuroxazide (Nifu) is a commonly used oral antibiotic with reported JAK/STAT3 inhibition activity. The present study investigated the potential protective effect of Nifu against diabetes-induced retinal injury. Effect of Nifu on oxidative stress, JAK/STAT3 axis and downstream inflammatory mediators has been also studied. Diabetes was induced in Sprague Dawley rats by single intraperitoneal injection of streptozotocin (50 mg/kg). Animals were assigned into four groups: normal, Nifu control, DM, and DM + Nifu. Nifu was orally administrated at 25 mg/kg/day for 8 weeks. The effects of Nifu on oxidative stress, JAK/STAT3 axis proteins, inflammatory factors, tight junction proteins, histological, and ultrastructural alterations were evaluated using spectrophotometry, gene and protein analyses, and histological studies. Nifu administration to diabetic rats attenuated histopathological and signs of retinal injury. Additionally, Nifu attenuated retinal oxidative stress, inhibited JAK and STAT3 phosphorylation, augmented the expression of STAT3 signaling inhibitor SOCS3, dampened the expression of transcription factor of inflammation NF-κB, and inflammatory cytokine TNF-α. Collectively, the current study indicated that Nifu alleviated DR progression in diabetic rats, suggesting beneficial retino-protective effect. This can be attributed to blocking JAK/STAT3 axis in retinal tissues with subsequent amelioration of oxidative stress and inflammation.

A single cell atlas of circulating immune cells involved in diabetic retinopathy

This study focused on examining the exact role of circulating immune cells in the development of diabetic retinopathy (DR). In vitro co-culture experiments showed that peripheral blood mononuclear cells (PBMCs) from patients with type 1 DR crucially modulated the biological functions of human retinal microvascular endothelial cells (HRMECs), consequently disrupting their normal functionality. Single-cell RNA sequencing (scRNA-seq) study revealed unique differentially expressed genes and pathways in circulating immune cells among healthy controls, non-diabetic retinopathy (NDR) patients, and DR patients. Of significance was the observed upregulation of JUND in each subset of PBMCs in patients with type 1 DR. Further studies showed that downregulating JUND in DR patient-derived PBMCs led to the amelioration of HRMEC dysfunction. These findings highlighted the notable alterations in the transcriptomic patterns of circulating immune cells in type 1 DR patients and underscored the significance of JUND as a key factor for PBMCs in participating in the pathogenesis of DR.

SIRT1: a promising therapeutic target in type 2 diabetes mellitus

A significant increase in the worldwide incidence and prevalence of type 2 diabetic mellitus (T2DM) has elevated the need for studies on novel and effective therapeutic strategies. Sirtuin 1 (SIRT1) is an NAD + dependent protein deacetylase with a critical function in the regulation of glucose/lipid metabolism, insulin resistance, inflammation, oxidative stress, and mitochondrial function. SIRT1 is also involved in the regulation of insulin secretion from pancreatic β-cells and protecting these cells from inflammation and oxidative stress-mediated tissue damages. In this regard, major SIRT1 activators have been demonstrated to exert a beneficial impact in reversing T2DM-related complications including cardiomyopathy, nephropathy, retinopathy, and neuropathy, hence treating T2DM. Therefore, an accumulating number of recent studies have investigated the efficacy of targeting SIRT1 as a therapeutic strategy in T2DM. In this review we aimed to discuss the current understanding of the physiological and biological roles of SIRT1, then its implication in the pathogenesis of T2DM, and the therapeutic potential of SIRT1 in combating T2DM.

Insights Into Visual Rehabilitation: Pan-Retinal Photocoagulation for Proliferative Diabetic Retinopathy

This review comprehensively explores pan-retinal photocoagulation (PRP) as a pivotal intervention in visually rehabilitating individuals afflicted with proliferative diabetic retinopathy (PDR). The review begins by elucidating the significance of PDR within the spectrum of diabetic retinopathy (DR), emphasizing the progressive nature of the disease and the consequential impact on visual health. A detailed analysis of PRP follows, encompassing its definition, purpose, and historical development, shedding light on the procedural intricacies and mechanisms of action. The postoperative care and follow-up section underscores the necessity of vigilant monitoring for complications, visual recovery, and the importance of regular ophthalmic check-ups. The subsequent discussion delves into patient education and counseling, stressing the need to manage expectations, encourage lifestyle modifications, and highlight the significance of follow-up appointments. The review concludes with insights into future directions, including advancements in laser technology and emerging therapies, offering a glimpse into the evolving landscape of DR management. By addressing ongoing challenges and embracing innovative approaches, this review provides a comprehensive guide for clinicians, researchers, and healthcare practitioners who visually rehabilitate individuals struggling with PDR.

The role of cadre in the community on diabetic retinopathy management and its challenges in low-middle income countries: a scoping review

INTRODUCTION

Diabetes is a serious public health problem, with low- and middle-income countries (LMICs) bearing over 80% of the burden. Diabetic retinopathy (DR) is one of the most prevalent diabetic microvascular problems, and early diagnosis through eye screening programs for people with diabetes is critical to prevent vision impairment and blindness. Community-based treatments, including non-physician cadres have been recommended to enhance DR care.

METHODS

The review protocol was determined and scoping review was conducted.The population, concept, and context were "cadre", "role of cadre in the management of DR", and LMICs". Data were collected from databases and searches, including grey literature.

RESULTS

Cadre can motivate people to attend a diabetic eye screening event when the rate of eye examinations is about six times higher than before the start of the intervention. Health education is a possible area for task sharing, and the cadre reported could also perform the task of vision testing. The cadre could be a good supporter and a good reminder for society. However, several challenges have been faced in this study and inadequate infrastructure is the foremost challenge found in this study. Other challenges encountered in the studies include poverty, lack of community awareness, trust issues, and low education levels contributing to poor health.

CONCLUSION

The current study highlighted significant gaps in the literature, which focus on the role of cadre as a community-based intervention in managing DR in LMICs. Further research is needed to develop evidence to support cost-effective screening services and cadre-related policy development in LMICs.

Association between serum heavy metal levels and diabetic retinopathy in NHANES 2011-2020

The present study utilized the National Health and Nutrition Examination Survey (NHANES) database to examine the relationship between serum levels of heavy metals and Diabetic retinopathy (DR) in individuals aged over 30 years with type 2 diabetes mellitus (T2DM) in the United States. A cross-sectional analysis was conducted on 1583 individuals with T2DM from the NHANES 2011-2020, including 331 individuals in the DR group and 1252 individuals in the non-DR group. We collected data on serum levels of heavy metals, DR, and serum albumin for descriptive statistics, linear regression, and logistical regression analysis. After adjusting for age, gender, race and other factors, there was no statistically significant association between blood cadmium, selenium, mercury, or lead and DR. However, serum manganese (Mn) and DR had a significant negative association (β = - 0.2045, 95% CI = - 0.3484, - 0.0606). Serum albumin partially modulated the indirect influence of serum Mn on the incidence of DR, accounting for 12.80% of the association between serum Mn and DR. There was a negative association between serum Mn levels and the prevalence of DR in people with T2DM. Mn intake at least in this study has a little influence on the onset and development of DR.

Analysis of risk factors of infection in diabetic foot patients

This cross-sectional study assessed the risk factors for infection in 150 diabetic foot patients admitted to the Xiamen University Hospital between October 2020 and October 2022. Patients were categorised as infected (n = 80) or uninfected (n = 70) cohorts. The diabetic foot was evaluated using the American Diabetic Foot Grading system, whereas ulcers were categorised using Wagner's method. Analysed were patient-specific information, clinical data and risk factors including neuropathy, arterial disease and foot deformities. Our findings revealed no statistically significant differences between infected and uninfected cohorts concerning age, body mass index, gender, duration of diabetes or ankle-brachial index values (p > 0.05). However, infected group had a higher proportion of smokers and reduced socio-economic status (p < 0.05). Wagner grades indicated a greater severity in the infected group, with grade 3, grade 4 and grade 5 differing significantly (p < 0.05). Comparative analysis of ulcer characteristics revealed no statistically significant differences in ulcer surface area and depth, but the infected group had a higher prevalence of osteomyelitis and a greater number of ulcers (p > 0.05). Blood vessel complications, retinopathy, the presence of three or more ulcers, osteomyelitis and diabetic nephropathy were substantially more prevalent in the infected group, as determined by univariate analysis (p < 0.05). Subsequent multivariate logistic analysis revealed that patients with blood vessel complications, retinopathy, osteomyelitis, diabetic nephropathy and three or more ulcers were at increased risk for infection (p < 0.05). In addition, lifestyle factors, such as smoking, sedentary behaviour, inadequate foot hygiene, obesity and poor glycaemic control, were also associated with higher infection rates. A multivariate analysis of foot wound factors revealed that deeper, longer and recurrent lesions increased the likelihood of infection. Escherichia coli was the most frequently isolated bacterium from the infected group's bacterial culture, followed by Pseudomonas aeruginosa and Staphylococcus aureus. The study enhanced our comprehension of the multifactorial risk factors associated with infections in diabetic foot patients, highlighting the need for thorough clinical evaluation, lifestyle modification and vigilant infection control.

The effect of a new design of patient gowns for prone position patients after vitrectomy: A non-randomized, concurrent, controlled study

BACKGROUND

The existing patient clothing is not suitable for patients that have to maintain a prone position for a long time after vitrectomy.

OBJECTIVE

To investigate the effect of a new design of patient gowns for prone position patients after vitrectomy.

METHOD

This study designed a kind of patient's gown for prone position patients. A non-randomized, concurrent, controlled study was conducted on 212 patients who met the inclusion criteria for the prone position after vitrectomy in Grade III at a Class A hospital department of ophthalmology in Zhejiang Province from April to August 2020. The experimental group (106 patients in prone position) and the control group (106 patients in common position) were managed by the same group of nurses. The study recorded and compared the comfort degree of patients' clothing used in the course of operation rehabilitation between the two groups and the satisfaction degree of doctors with nurses to patients' clothing used in the prone position.

RESULTS

The satisfaction degree and comfort degree of patients and the health care providers in the experiment group were significantly higher than those in the control group (p< 0.001).

CONCLUSION

The process of making patient gowns for prone position patients is simple, which can improve the safety and comfort of patients when they were in the prone position. The new design also facilitated the treatment and nursing procedures of the medical staff and improved satisfaction among patients and medical staff.

Association of lactate dehydrogenase and diabetic retinopathy in US adults with diabetes mellitus

OBJECTIVES

The purpose of our investigation is to evaluate the level of relationship between lactate dehydrogenase (LDH) and the occurrence of diabetic retinopathy (DR) in adults with diabetes mellitus (DM).

METHODS

The investigation involved an analysis of five sectional data cycles acquired from the National Health and Nutrition Examination Survey from 2009 to 2018. The present study involved the selection of DM samples from a complex multistage probability sample. These samples were subsequently classified into two distinct groups, namely the No DR (NDR) and DR groups. The present study comprehensively investigated the biological and social risk factors associated with DR. The biological factors examined in this investigation included blood pressure, blood routine, hemoglobin A1c, blood glucose, and comorbidities. The social dimensions encompass education and sex.

RESULTS

After considering all factors, multivariate regression models indicated a significant relationship between DR and increased LDH (adjusted odds ratio = 1.007, 95% confidence interval: 1.003-1.011). The subgroup analysis revealed that the effect size of LDH on the existence of DR in the subgroups remained consistent, as indicated by all p values greater than .05. A statistically significant relationship was identified between elevated LDH levels > 134 U/L and a raised risk of DR in people with DM.

CONCLUSION

LDH concentrations were connected with an increased prevalence of DR in participants with DM. Our study highlights that patients with LDH > 134 U/L are distinguishably related to DM complicated by DR. DR is more common in diabetic individuals with coronary heart disease.

Identification of key genes modules linking diabetic retinopathy and circadian rhythm

Background

Diabetic retinopathy (DR) is a leading cause of vision loss worldwide. Recent studies highlighted the crucial impact of circadian rhythms (CR) on normal retinopathy in response to the external light cues. However, the role of circadian rhythms in DR pathogenesis and potential investigational drugs remains unclear.

Methods

To investigate the weather CR affects DR, differential expression analysis was employed to identify differentially expressed genes (DEGs) from the GEO database (GSE160306). Functional enrichment analysis was conducted to identify relevant signaling pathways. LASSO regression was utilized to screen pivotal genes. Weighted gene co-expression network anlaysis (WGCNA) was applied to identify different modules. Additionally, we use the Comparative Toxicogenomics Database (CTD) database to search key genes related to drugs or molecular compounds. The diabetic mouse model received three consecutive intraperitoneal injections of streptozotocin (STZ) during 3 successive days.

Results

We initially identified six key genes associated with circadian rhythm in DR, including COL6A3, IGFBP2, IGHG4, KLHDC7A, RPL26P30, and MYL6P4. Compared to normal tissue, the expression levels of COL6A3 and IGFB2 were significantly increased in DR model. Furthermore, we identified several signaling pathways, including death domain binding, insulin-like growth factor I binding, and proteasome binding. We also observed that COL6A3 was positively correlated with macrophages (cor=0.628296895, p=9.96E-08) and Th17 cells (cor=0.665120835, p=9.14E-09), while IGFBP2 showed a negatively correlated with Tgd (cor=-0.459953045, p=0.000247284) and Th2 cells (cor=-0.442269719, p=0.000452875). Finally, we identified four drugs associated with key genes: Resveratrol, Vitamin E, Streptozocin, and Sulindac.

Conclusion

Our findings revealed several key genes related to circadian rhythms and several relevant drugs in DR, providing a novel insight into the mechanism of DR and potential implications for future DR treatment. This study contributes to a better understanding of CR in DR and its implications for future therapeutic interventions.

Stem cells as a regenerative medicine approach in treatment of microvascular diabetic complications

Diabetes mellitus (DM) is a chronic metabolic disorder characterized by high blood glucose and is associated with high morbidity and mortality among the diabetic population. Uncontrolled chronic hyperglycaemia causes increased formation and accumulation of different oxidative and nitrosative stress markers, resulting in microvascular and macrovascular complications, which might seriously affect the quality of a patient's life. Conventional treatment strategies are confined to controlling blood glucose by regulating the insulin level and are not involved in attenuating the life-threatening complications of diabetes mellitus. Thus, there is an unmet need to develop a viable treatment strategy that could target the multi-etiological factors involved in the pathogenesis of diabetic complications. Stem cell therapy, a regenerative medicine approach, has been investigated in diabetic complications owing to their unique characteristic features of self-renewal, multilineage differentiation and regeneration potential. The present review is focused on potential therapeutic applications of stem cells in the treatment of microvascular diabetic complications such as nephropathy, retinopathy, and polyneuropathy.

Suprachoroidal triamcinolone versus posterior subtenon triamcinolone either alone or formulated in the management of diabetic macular edema

PURPOSE

This study aims to compare posterior subtenon triamcinolone acetonide injection either formulated or alone versus suprachoroidal triamcinolone in the management of diabetic macular edema.

METHODS

This study is a prospective interventional study that included 75 patients, divided into three groups, each group with 25 patients. Group I received a combination of triamcinolone acetonide (TA) (40 mg) and VISCOAT, which is a combination of sodium chondroitin sulfate (20 mg) and sodium hyaluronate (15 mg). The injection was done in the posterior subtenon space using the NAGATA cannula. Group II received TA (40 mg) in the posterior subtenon space. Group III underwent an injection of 4 mg/100µl of TA in the supra choroidal space.

RESULTS

We found a statistically significant difference between the three studied groups regarding BCVA (P = 0.001) and CMT at six months postoperative (P = 0.001) with the highest median BCVA and lowest median CMT observed in the formulated TA group.

CONCLUSION

We concluded that early treatment of DME by formulated TA is better than TA alone, and suprachoroidal TA in the form of increasing the BCVA and decreasing the CMT without any elevation of IOP. Trial registration number NCT05464953. Date of registration 17/7/2022 (retrospectively registered).

Evaluation of Quality of Life and Emotional Disturbances in Patients with Diabetic Retinopathy

Diabetes has detrimental effects on many organs, including the kidneys, heart, and the central nervous system, with ophthalmic involvement and Diabetic Retinopathy (DR), specifically, being among the most severe and prominent consequences. Diabetic Retinopathy and especially advanced stages of the disease, have a crucial impact on patients' quality of life and emotional status. In this context, emotional imbalance, psychological side effects and comorbidities, like anxiety disorders, could emerge, deteriorating the patients' condition further. A number of questionnaires can be employed in the evaluation of the potential impact of Diabetic Retinopathy on patients' quality of life, including the Beck Anxiety Inventory (BAI) and The National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25).

PURPOSE

The purpose of this study was to evaluate the association of Diabetic Retinopathy (DR) and diabetic macular edema with vision-related quality of life, as well as the potential association between the disease's severity, emotional status of patients and the manifestation of anxiety and psychological features.

RESULTS

Patients with fundoscopic findings had significantly lower scores in all VFQ-25 subscales, indicating worse quality of life in comparison to patients without DR. Severity of DR, greater levels of anxiety, daily sitting time, unemployment and lower education level, were all found to be significantly, negatively associated with a worse quality of life. Regarding emotional status, more years of suffering from diabetes, treatment with insulin and the hours being idle per day were associated with an increased burden of anxiety. In addition, the presence of a concomitant disease, findings in fundoscopy, diabetic macular edema and treatment with anti-VEFG injections, as well as the number of doses, were significantly associated with greater anxiety. Multivariate analysis showed that having Severe Non-Proliferative Diabetic Retinopathy or having Proliferative Diabetic Retinopathy and receiving insulin therapy (alone or in combination with another treatment), were significantly associated with higher levels of anxiety.

CONCLUSION

The well-established impact of DR on the patients' well-being, quality of life and emotional status render DR and CME prevention, stabilization or delaying progression as a necessity in order to protect patients from developing psychiatric symptoms. On the other hand, the speculated bi-directional association between emotional problems and DR progression highlights the importance of acknowledging and dealing with psychological issues with the aim of delaying DR progression.

A cohort follow-up study for diabetic retinopathy screening incidence in the North Denmark Region

AIMS

To evaluate diabetic retinopathy (DR) screening incidence in a universal healthcare system.

METHODS

Registry-based cohort study based on a Danish regional population from 2009 to 2018. Individuals with diabetes were identified by medication. Screening attendance was estimated by surrogate measures using local and nationwide databases reported by cumulative incidence.

RESULTS

18,832 patients were included. By the end of the first year, the cumulative incidence of screening for DR was 60.2% and by the end of the second year 74.2%. The cumulative incidence was 93.9% overall, 97.7% for patients with type 1 diabetes (T1D) and 93.4% for patients with type 2 diabetes. Screening proportions per 1, 2 and 5 years were calculated. Females, patients with T1D, and patients attending screening at hospitals had a higher Hazard Ratio of 1.084, 1.157, and 1.573, respectively. The Cochran-Armitage trend test indicated increased screening frequency from 2009 to 2018. Validation of DR screening was done at hospitals with a mean positive predictive value of 86.78%. Cumulative incidence curves showed a small right shift when censoring the first, second and third screening visits.

CONCLUSIONS

Nearly all patients were screened for DR over a 5-year timespan. Female patients with T1D who attended screening at hospitals were significantly more likely to be screened. Validation of screening visits at hospitals was reported with a high mean positive predictive value. Most other studies, to the best of our knowledge, only report screening attendance for patients already enrolled in a DR screening programme. This study describes the overall screening attendance for the total eligible diabetes population.

Prevalence of bacillary layer detachment in diabetic macular edema and response to 3 anti-vascular endothelial growth factor treatment

Spectral-domain optical coherence tomography is widely used in maculopathy, including diabetic macular edema (DME). Bacillary layer detachment (BALAD) is a novel optical coherence tomography finding, defined as the separation of the intraretinal layer between the inner segment myoids and ellipsoids. A total of 161 treatment-naïve eyes with centrally involved DME that underwent 3 monthly loading doses of anti-vascular endothelial growth factor (anti-VEGF) intravitreal injections were enrolled and analyzed retrospectively. BALAD was found in 6.2% of eyes with concurrent subretinal fluid (SRF). All eyes were divided into 3 groups: no either group had neither SRF or BALAD; the SRF only group had SRF but no BALAD; and the BALAD group had both SRF and BALAD. A significant increase in baseline central foveal thickness (CFT) in the BALAD group was observed (no either vs SRF only vs BALAD, baseline CFT: 387.6 ± 74.29 vs 440.6 ± 106.79 vs 642.0 ± 188.86; P < .01). Total resolution of BALAD was noted after anti-VEGF therapy, along with a significant decrease in CFT in all groups (CFT decrease: 82.4 ± 87.07 vs 187.6 ± 138.88 vs 252.1 ± 127.63; P < .01). Eyes with BALAD tended to have the worst baseline visual acuity (baseline logarithm of the minimum angle of resolution VA: 0.76 ± 0.353 vs 0.63 ± 0.303 vs 1.15 ± 0.300; P = .046) but showed the most improvement after treatment (logarithm of the minimum angle of resolution VA change: -0.14 ± 0.235 vs -0.22 ± 0.275 vs -0.27 ± 0.250; P = .079). After resolution of BALAD, all eyes in the BALAD group exhibited ellipsoid zone and/or interdigitation zone disruption corresponding to the BALAD area. BALAD is a novel optical coherence tomography finding associated with a spectrum of diseases including DME. With anti-VEGF therapy, total resolution of BALAD and a significant decrease in CFT can be obtained. However, ellipsoid zone/interdigitation zone disruption tended to develop.

CHILDSTAR: CHIldren Living With Diabetes See and Thrive with AI Review

Background

Artificial intelligence (AI) appears capable of detecting diabetic retinopathy (DR) with a high degree of accuracy in adults; however, there are few studies in children and young adults.

Methods

Children and young adults (3-26 years) with type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM) were screened at the Dhaka BIRDEM-2 hospital, Bangladesh. All gradable fundus images were uploaded to Cybersight AI for interpretation. Two main outcomes were considered at a patient level: 1) Any DR, defined as mild non-proliferative diabetic retinopathy (NPDR or more severe; and 2) Referable DR, defined as moderate NPDR or more severe. Diagnostic test performance comparing Orbis International's Cybersight AI with the reference standard, a fully qualified optometrist certified in DR grading, was assessed using the Matthews correlation coefficient (MCC), area under the receiver operating characteristic curve (AUC-ROC), area under the precision-recall curve (AUC-PR), sensitivity, specificity, positive and negative predictive values.

Results

Among 1274 participants (53.1% female, mean age 16.7 years), 19.4% (n = 247) had any DR according to AI. For referable DR, 2.35% (n = 30) were detected by AI. The sensitivity and specificity of AI for any DR were 75.5% (CI 69.7-81.3%) and 91.8% (CI 90.2-93.5%) respectively, and for referable DR, these values were 84.2% (CI 67.8-100%) and 98.9% (CI 98.3%-99.5%). The MCC, AUC-ROC and the AUC-PR for referable DR were 63.4, 91.2 and 76.2% respectively. AI was most successful in accurately classifying younger children with shorter duration of diabetes.

Conclusions

Cybersight AI accurately detected any DR and referable DR among children and young adults, despite its algorithms having been trained on adults. The observed high specificity is particularly important to avoid over-referral in low-resource settings. AI may be an effective tool to reduce demands on scarce physician resources for the care of children with diabetes in low-resource settings.

LncRNA SNHG4 sponges miR-200b to inhibit cell apoptosis in diabetic retinopathy

This study aimed to investigate the role of long non-coding RNA (lncRNA) small nucleolar RNA host gene 4 (SNHG4) in diabetic retinopathy (DR). We found that SNHG4 was downregulated in DR. SNHG4 could directly interact with miR-200b, while overexpression of miR-200b did not affect the expression of SNHG4 in human retinal pigment epithelial cells ARPE-19. In contrast, overexpression of SNHG4 led to the upregulation of oxidation resistance 1 (Oxr1), a target of miR-200b. Cell apoptosis analysis showed that overexpression of miR-200b increased the apoptotic rate of ARPE-19 cells under high glucose treatment. Oxr1 and SNHG4 played opposite roles and reduced the effects of overexpression of miR-200b. In conclusion, SNHG4 may sponge miR-200b to inhibit cell apoptosis in DR by upregulating Oxr1.

Relationship between ocular surface pain and corneal nerve loss in dry eye diabetics: a cross-sectional study in Shenyang, China

BACKGROUND

Diabetes mellitus has been associated with increased dry eye disease (DED) and exacerbates DED pathology.

OBJECTIVE

To investigate the potential relationship between corneal nerve loss and ocular pain among diabetic patients with dry eye (DE).

DESIGN

A cross-sectional study.

SETTING

He Eye Specialist Hospital, Shenyang, China.

PARTICIPANTS

This study recruited 124 eyes of 62 diabetic patients diagnosed with DED between August and October 2022.

MAIN OUTCOME MEASURES

Best-corrected visual acuity, intraocular pressure, non-invasive tear breakup time, tear meniscus height, tear film lipid layer, conjunctival hyperaemia (redness score), conjunctivocorneal epithelial staining (CS score), central corneal sensitivity and vitro confocal corneal microscopy was assessed in all subjects. The Ocular Surface Disease Index Questionnaire assessed DE symptoms and ocular pain.

RESULTS

The study's final analysis included 26 patients (52 eyes) without ocular pain and 36 patients (72 eyes) with ocular pain. The corneal nerve fibre density (CNFD), corneal nerve branch density (CNBD) and corneal nerve fibre length (CNFL) in patients with ocular pain were significantly lower than those without (p<0.001, p=0.004, and p<0.001, respectively). CNFD, CNBD and CNFL negatively correlated with ocular pain (r=-0.385, r=-0.260, r=-0.358, respectively). Moreover, CNFD, CNBD and CNFL have a significant (p<0.05) positive correlation with corneal sensitivity (r=0.523, r=0.330, r=0.421, respectively).

CONCLUSIONS

Corneal nerve loss was associated with ocular pain and decreased corneal sensitivity in diabetic patients with DE. Further studies into the neurological role of ocular surface diseases can elaborate diagnostics, prognosis and treatment of diabetic patients with DE.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT05193331).

Optimizing the OCTA layer fusion option for deep learning classification of diabetic retinopathy

The purpose of this study is to evaluate layer fusion options for deep learning classification of optical coherence tomography (OCT) angiography (OCTA) images. A convolutional neural network (CNN) end-to-end classifier was utilized to classify OCTA images from healthy control subjects and diabetic patients with no retinopathy (NoDR) and non-proliferative diabetic retinopathy (NPDR). For each eye, three en-face OCTA images were acquired from the superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris (CC) layers. The performances of the CNN classifier with individual layer inputs and multi-layer fusion architectures, including early-fusion, intermediate-fusion, and late-fusion, were quantitatively compared. For individual layer inputs, the superficial OCTA was observed to have the best performance, with 87.25% accuracy, 78.26% sensitivity, and 90.10% specificity, to differentiate control, NoDR, and NPDR. For multi-layer fusion options, the best option is the intermediate-fusion architecture, which achieved 92.65% accuracy, 87.01% sensitivity, and 94.37% specificity. To interpret the deep learning performance, the Gradient-weighted Class Activation Mapping (Grad-CAM) was utilized to identify spatial characteristics for OCTA classification. Comparative analysis indicates that the layer data fusion options can affect the performance of deep learning classification, and the intermediate-fusion approach is optimal for OCTA classification of DR.

Knowledge, Attitude, and Practice Regarding Diabetic Retinopathy Screening and Eye Management Among Diabetics in Saudi Arabia

Background Globally, one of the leading causes of blindness is diabetic retinopathy (DR). However, many patients do not participate in DR screening because of a lack of awareness. This study aims to assess the knowledge, attitude, and practice (KAP) level regarding DR screening and eye management among diabetic patients in Saudi Arabia. Methodology This cross-sectional study was conducted among diabetic patients aged 18 years or older in Saudi Arabia between October 2022 and February 2023. A validated online KAP-36 questionnaire collected information on sociodemographic data, diabetes profile, diabetes-related complications, and KAP regarding DR screening and management. Results Of the 1,391 diabetic patients, 736 (52.9%) had good knowledge about DR screening and care, while 655 (47.1%) had poor knowledge. A positive attitude toward eye examination for the early detection of DR was noticed among 1,124 (80.8%) participants. Regarding the participants' practice of regular fundus examination, 1,000 (71.9%) participants had good practice. Significant relationships were found between education level (p = 0.017), diabetes mellitus (DM) type and duration (p= 0.01, 0.02), type of treatment (p = 0.001), and a high degree of knowledge. Significant determinants of patients' favorable attitudes included their type of diabetes (p = 0.003), region of residence (p = 0.038), and work or education outside the medical field (p = 0.001). Age (p = 0.001), location of residence (p = 0.015), educational attainment (p= 0.041), and type of diabetes (p = 0.045) were the factors that determined good practice. Conclusions Many diabetic patients supported DR screening and engaged in it regularly. Unfortunately, only around half of the participants had a good understanding of DR. Type 2 diabetes mellitus (T2DM), a longer history of DM, and being highly educated were factors associated with a diabetic patient's higher level of knowledge. Positive attitudes were significantly higher among those living in the central Saudi region, employed outside of the medical field, and those with T2DM. Finally, regarding the practice of eye screening and management among diabetic patients, elderly patients living in the southern Saudi region and those with T2DM were adherent to their regular eye examinations. Consequently, the key to ensuring adequate adherence to DR screening may be intervention techniques and focused education to increase patients' knowledge of DR.

Imaging Biomarkers of Mesopic and Dark-Adapted Macular Functions in Eyes With Treatment-Naïve Mild Diabetic Retinopathy

PURPOSE

To investigate the relationship between imaging biomarkers and mesopic and dark-adapted (ie, scotopic) functions in patients with treatment-naïve mild diabetic retinopathy (DR) and normal visual acuity.

DESIGN

Prospective cross-sectional study.

METHODS

In this study, 60 patients with treatment-naïve mild DR (Early Treatment of Diabetic Retinopathy Study levels 20-35) and 30 healthy control subjects underwent microperimetry, structural optical coherence tomography (OCT), and OCT angiography (OCTA).

RESULTS

The foveal mesopic (22.4 ± 4.5 dB and 25.8 ± 2.0 dB, P = .005), parafoveal mesopic (23.2 ± 3.8 and 25.8 ± 1.9, P < .0001), and parafoveal dark-adapted (21.1 ± 2.8 dB and 23.2 ± 1.9 dB, P = .003) sensitivities were reduced in DR eyes. For foveal mesopic sensitivity, the regression analysis showed a significant topographic association with choriocapillaris flow deficits percentage (CC FD%; β = -0.234, P = .046) and ellipsoid zone (EZ) normalized reflectivity (β = 0.282, P = .048). Parafoveal mesopic sensitivity was significantly topographically associated with inner retinal thickness (β = 0.253, P = .035), deep capillary plexus (DCP) vessel length density (VLD; β = 0.542, P = .016), CC FD% (β = -0.312, P = .032), and EZ normalized reflectivity (β = 0.328, P = .031). Similarly, parafoveal dark-adapted sensitivity was topographically associated with inner retinal thickness (β = 0.453, P = .021), DCP VLD (β = 0.370, P = .030), CC FD% (β = -0.282, P = .048), and EZ normalized reflectivity (β = 0.295, P = .042).

CONCLUSIONS

In treatment-naïve mild DR eyes, both rod and cone functions are affected and they are associated with both DCP and CC flow impairment, which suggests that a macular hypoperfusion at these levels might implicate a reduction in photoreceptor function. Normalized EZ reflectivity may be a valuable structural biomarker for assessing photoreceptor function in DR. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Postoperative opioid prescribing patients with diabetes: Opportunities for personalized pain management

BACKGROUND

Opioids are commonly prescribed for postoperative pain, but may lead to prolonged use and addiction. Diabetes impairs nerve function, complicates pain management, and makes opioid prescribing particularly challenging.

METHODS

This retrospective observational study included a cohort of postoperative patients from a multisite academic health system to assess the relationship between diabetes, pain, and prolonged opioid use (POU), 2008-2019. POU was defined as a new opioid prescription 3-6 months after discharge. The odds that a patient had POU was assessed using multivariate logistic regression controlling for patient factors (e.g., demographic and clinical factors, as well as prior pain and opiate use).

FINDINGS

A total of 43,654 patients were included, 12.4% with diabetes. Patients with diabetes had higher preoperative pain scores (2.1 vs 1.9, p<0.001) and lower opioid naïve rates (58.7% vs 68.6%, p<0.001). Following surgery, patients with diabetes had higher rates of POU (17.7% vs 12.7%, p<0.001) despite receiving similar opioid prescriptions at discharge. Patients with Type I diabetes were more likely to have POU compared to other patients (Odds Ratio [OR]: 2.22; 95% Confidence Interval [CI]:1.69-2.90 and OR:1.44, CI: 1.33-1.56, respectively).

INTERPRETATION

In conclusion, surgical patients with diabetes are at increased risk for POU even after controlling for likely covariates, yet they receive similar postoperative opiate therapy. The results suggest a more tailored approach to diabetic postoperative pain management is warranted.

SLC22A3 rs2048327 Polymorphism Is Associated with Diabetic Retinopathy in Caucasians with Type 2 Diabetes Mellitus

The Solute Carrier Family 22 Member 3 (SLC22A3) is a high-capacity, low-affinity transporter for the neurotransmitters norepinephrine, epinephrine, dopamine, serotonin, and histamine. SLC22A3 plays important roles in interorgan and interorganism small-molecule communication, and also regulates local and overall homeostasis in the body. Our aim was to investigate the association between the rs2048327 gene polymorphism and diabetic retinopathy (DR) in Slovenian patients with type 2 diabetes mellitus (T2DM). We also investigated SLC22A3 expression in the fibrovascular membranes (FVMs) of patients with proliferative DR (PDR). Our study involved 1555 unrelated Caucasians with T2DM with a defined ophthalmologic status: 577 of them with DR as the study group, and 978 without DR as the control group. The investigated polymorphisms were genotyped using the KASPar genotyping assay. The expression of SLC22A3 (organic cation transporter 3-OCT3) was examined via immunohistochemistry in human FVM from 16 patients with PDR. The C allele and CC genotype frequencies of the rs2048327 polymorphism were significantly higher in the study group compared to the controls. The logistic regression analysis showed that the carriers of the CC genotype in the recessive genetic models of this polymorphism have a 1.531-fold increase (95% CI 1.083-2.161) in the risk of developing DR. Patients with the C allele of rs2048327 compared to the homozygotes for the wild type T allele exhibited a higher density of SLC22A3 (OCT3)-positive cells (10.5 ± 4.5/mm2 vs. 6.1 ± 2.7/mm2, respectively; p < 0.001). We showed the association of the rs2048327 SLC22A3 gene polymorphism with DR in a Slovenian cohort with type 2 diabetes mellitus, indicating its possible role as a genetic risk factor for the development of this diabetic complication.

Competing risks analysis for neutrophil to lymphocyte ratio as a predictor of diabetic retinopathy incidence in the Scottish population

BACKGROUND

Diabetic retinopathy (DR) is a major sight-threatening microvascular complication in individuals with diabetes. Systemic inflammation combined with oxidative stress is thought to capture most of the complexities involved in the pathology of diabetic retinopathy. A high level of neutrophil-lymphocyte ratio (NLR) is an indicator of abnormal immune system activity. Current estimates of the association of NLR with diabetes and its complications are almost entirely derived from cross-sectional studies, suggesting that the nature of the reported association may be more diagnostic than prognostic. Therefore, in the present study, we examined the utility of NLR as a biomarker to predict the incidence of DR in the Scottish population.

METHODS

The incidence of DR was defined as the time to the first diagnosis of R1 or above grade in the Scottish retinopathy grading scheme from type 2 diabetes diagnosis. The effect of NLR and its interactions were explored using a competing risks survival model adjusting for other risk factors and accounting for deaths. The Fine and Gray subdistribution hazard model (FGR) was used to predict the effect of NLR on the incidence of DR.

RESULTS

We analysed data from 23,531 individuals with complete covariate information. At 10 years, 8416 (35.8%) had developed DR and 2989 (12.7%) were lost to competing events (death) without developing DR and 12,126 individuals did not have DR. The median (interquartile range) level of NLR was 2.04 (1.5 to 2.7). The optimal NLR cut-off value to predict retinopathy incidence was 3.04. After accounting for competing risks at 10 years, the cumulative incidence of DR and deaths without DR were 50.7% and 21.9%, respectively. NLR was associated with incident DR in both Cause-specific hazard (CSH = 1.63; 95% CI: 1.28-2.07) and FGR models the subdistribution hazard (sHR = 2.24; 95% CI: 1.70-2.94). Both age and HbA1c were found to modulate the association between NLR and the risk of DR.

CONCLUSIONS

The current study suggests that NLR has a promising potential to predict DR incidence in the Scottish population, especially in individuals less than 65 years and in those with well-controlled glycaemic status.

Clinical Outcomes of 27-Gauge Pars Plana Vitrectomy for Diabetic Tractional Retinal Detachment Repair

Purpose: To analyze the clinical outcomes of 27-gauge pars plana vitrectomy (PPV) repair of diabetic tractional retinal detachment (TRD) of various severities. Methods: This retrospective case series examined the outcomes of 27-gauge PPV to repair diabetic TRD from 2016 to 2020. The effect of medical and ophthalmologic history parameters and baseline detachment characteristics on visual acuity (VA) and retinal reattachment was analyzed. A grading system was established to stage the severity of the baseline vitreoretinal traction or detachment and compare the visual and anatomic outcomes between stages. Results: The study comprised 79 eyes (79 patients). The overall redetachment rate was 10.1% (8/79). The proportion of eyes with severe visual impairment (worse than 20/200) decreased from 81.0% (64/79) preoperatively to 56.9% (37/65) 6 months postoperatively (P < .001). Worse preoperative logMAR VA was associated with greater odds of redetachment (P = .017) and worse postoperative VA (P < .001). Insulin dependence was associated with better VA at 6 months (P = .017). A shorter known duration of diabetes (P = .026) and evidence of neovascularization of the iris (NVI) or angle (P = .004) were associated with worse visual outcomes. Eyes with detachment involving the posterior pole extending beyond the equator had worse VA at 6 months (P = .048). Conclusions: The primary reattachment rate after 27-gauge PPV was 89.9%. There was significant VA improvement, with a roughly 40% reduction in the number of eyes with severe visual impairment by the final follow-up. Insulin dependence, duration of diabetes, presence of NVI before surgery, and baseline posterior pole detachment extending beyond the equator were predictors of visual outcomes.

Proliferative Diabetic Retinopathy Diagnosis Using Varying-Scales Filter Banks and Double-Layered Thresholding

Diabetic retinopathy is one of the abnormalities of the retina in which a diabetic patient suffers from severe vision loss due to an affected retina. Proliferative diabetic retinopathy (PDR) is the final and most critical stage of diabetic retinopathy. Abnormal and fragile blood vessels start to grow on the surface of the retina at this stage. It causes retinal detachment, which may lead to complete blindness in severe cases. In this paper, a novel method is proposed for the detection and grading of neovascularization. The proposed system first performs pre-processing on input retinal images to enhance the vascular pattern, followed by blood vessel segmentation and optic disc localization. Then various features are tested on the candidate regions with different thresholds. In this way, positive and negative advanced diabetic retinopathy cases are separated. Optic disc coordinates are applied for the grading of neovascularization as NVD or NVE. The proposed algorithm improves the quality of automated diagnostic systems by eliminating normal blood vessels and exudates that might cause hindrances in accurate disease detection, thus resulting in more accurate detection of abnormal blood vessels. The evaluation of the proposed system has been carried out using performance parameters such as sensitivity, specificity, accuracy, and positive predictive value (PPV) on a publicly available standard retinal image database and one of the locally available databases. The proposed algorithm gives an accuracy of 98.5% and PPV of 99.8% on MESSIDOR and an accuracy of 96.5% and PPV of 100% on the local database.

Design, Synthesis, and Structure-Activity Relationships of Biaryl Anilines as Subtype-Selective PPAR-alpha Agonists

The role of peroxisome proliferator-activated receptor alpha (PPARα) in retinal biology is clarifying, and evidence demonstrates that novel PPARα agonists hold promising therapeutic utility for diseases like diabetic retinopathy and age-related macular degeneration. Herein, we disclose the design and initial structure-activity relationships for a new biaryl aniline PPARα agonistic chemotype. Notably, this series exhibits subtype selectivity for PPARα over other isoforms, a phenomenon postulated to be due to the unique benzoic acid headgroup. This biphenyl aniline series is sensitive to B-ring functionalization but allows isosteric replacement, and provides an opportunity for C-ring extension. From this series, 3g, 6j, and 6d were identified as leads with <90 nM potency in a cell-based luciferase assay cell and exhibited efficacy in various disease-relevant cell contexts, thereby setting the stage for further characterization in more advanced in vitro and in vivo models.

Inhibition of Galectins and the P2X7 Purinergic Receptor as a Therapeutic Approach in the Neurovascular Inflammation of Diabetic Retinopathy

Diabetic retinopathy (DR) is the most frequent microvascular retinal complication of diabetic patients, contributing to loss of vision. Recently, retinal neuroinflammation and neurodegeneration have emerged as key players in DR progression, and therefore, this review examines the neuroinflammatory molecular basis of DR. We focus on four important aspects of retinal neuroinflammation: (i) the exacerbation of endoplasmic reticulum (ER) stress; (ii) the activation of the NLRP3 inflammasome; (iii) the role of galectins; and (iv) the activation of purinergic 2X7 receptor (P2X7R). Moreover, this review proposes the selective inhibition of galectins and the P2X7R as a potential pharmacological approach to prevent the progression of DR.

Tocotrienol-rich fraction reduces retinal inflammation and angiogenesis in rats with streptozotocin-induced diabetes

BACKGROUND

Diabetic retinopathy (DR) is the second commonest microvascular complication of diabetes mellitus. It is characterized by chronic inflammation and angiogenesis. Palm oil-derived tocotrienol-rich fraction (TRF), a substance with anti-inflammatory and anti-angiogenic properties, may provide protection against DR development. Therefore, in this study, we investigated the effect of TRF on retinal vascular and morphological changes in diabetic rats. The effects of TRF on the retinal expression of inflammatory and angiogenic markers were also studied in the streptozotocin (STZ)-induced diabetic rats.

METHODS

Male Sprague Dawley rats weighing 200-250 g were grouped into normal rats (N) and diabetic rats. Diabetes was induced by intraperitoneal injection of streptozotocin (55 mg/kg body weight) whereas N similarly received citrate buffer. STZ-injected rats with blood glucose of more than 20 mmol/L were considered diabetic and were divided into vehicle-treated (DV) and TRF-treated (DT) groups. N and DV received vehicle, whereas DT received TRF (100 mg/kg body weight) via oral gavage once daily for 12 weeks. Fundus images were captured at week 0 (baseline), week 6 and week 12 post-STZ induction to estimate vascular diameters. At the end of experimental period, rats were euthanized, and retinal tissues were collected for morphometric analysis and measurement of NFκB, phospho-NFκB (Ser536), HIF-1α using immunohistochemistry (IHC) and enzyme-linked immunosorbent assay (ELISA). Retinal inflammatory and angiogenic cytokines expression were measured by ELISA and real-time quantitative PCR.

RESULTS

TRF preserved the retinal layer thickness (GCL, IPL, INL and OR; p < 0.05) and retinal venous diameter (p < 0.001). TRF also lowered the retinal NFκB activation (p < 0.05) as well as expressions of IL-1β, IL-6, TNF-α, IFN-γ, iNOS and MCP-1 (p < 0.05) compared to vehicle-treated diabetic rats. Moreover, TRF also reduced retinal expression of VEGF (p < 0.001), IGF-1 (p < 0.001) and HIF-1α (p < 0.05) compared to vehicle-treated rats with diabetes.

CONCLUSION

Oral TRF provided protection against retinal inflammation and angiogenesis in rats with STZ-induced diabetes by suppressing the expression of the markers of retinal inflammation and angiogenesis.

Inactive matrix Gla protein in relation to diabetic retinopathy in type 2 diabetes

Background and Aims

The contribution of inactive Matrix Gla protein (MGP) to ectopic vascular calcification associated with type 2 diabetes mellitus (T2DM) is well recognized. However, its role in diabetic microvascular complications remains unknown. The study aim was to identify any association between inactive MGP and diabetic retinopathy (DR). Its relation to insulin resistance was also explored.

Methods

The study included 90 participants, 65 Type 2 diabetic patients (25 without DR and 40 with DR) and 25 healthy controls. Serum inactive MGP was measured using ELISA. HOMA-IR was also assessed.

Results

Inactive MGP was significantly higher in both diabetic groups compared to controls (P < 0.001), as well as in Type 2 diabetic patients with retinopathy compared to Type 2 diabetes without retinopathy (P = 0.002). Inactive MGP was positively correlated with HbA1c, HOMA-IR, LDL-C and triglycerides (P < 0.001), and negatively correlated with HDL-C (P = 0.008) and eGFR (P < 0.001). Logistic Regression Analysis showed that inactive MGP was one of the most associated factors with DR.

Conclusions

Inactive MGP was found to be related to DR, insulin resistance and other dysmetabolic risk factors. These findings highlight that inactive MGP may be a significant contributor to the pathogenesis, evolution, and progression of DR.

Development of revised ResNet-50 for diabetic retinopathy detection

BACKGROUND

Diabetic retinopathy (DR) produces bleeding, exudation, and new blood vessel formation conditions. DR can damage the retinal blood vessels and cause vision loss or even blindness. If DR is detected early, ophthalmologists can use lasers to create tiny burns around the retinal tears to inhibit bleeding and prevent the formation of new blood vessels, in order to prevent deterioration of the disease. The rapid improvement of deep learning has made image recognition an effective technology; it can avoid misjudgments caused by different doctors' evaluations and help doctors to predict the condition quickly. The aim of this paper is to adopt visualization and preprocessing in the ResNet-50 model to improve module calibration, to enable the model to predict DR accurately.

RESULTS

This study compared the performance of the proposed method with other common CNNs models (Xception, AlexNet, VggNet-s, VggNet-16 and ResNet-50). In examining said models, the results alluded to an over-fitting phenomenon, and the outcome of the work demonstrates that the performance of the revised ResNet-50 (Train accuracy: 0.8395 and Test accuracy: 0.7432) is better than other common CNNs (that is, the revised structure of ResNet-50 could avoid the overfitting problem, decease the loss value, and reduce the fluctuation problem).

CONCLUSIONS

This study proposed two approaches to designing the DR grading system: a standard operation procedure (SOP) for preprocessing the fundus image, and a revised structure of ResNet-50, including an adaptive learning rating to adjust the weight of layers, regularization and change the structure of ResNet-50, which was selected for its suitable features. It is worth noting that the purpose of this study was not to design the most accurate DR screening network, but to demonstrate the effect of the SOP of DR and the visualization of the revised ResNet-50 model. The results provided an insight to revise the structure of CNNs using the visualization tool.

Normalized Blood Flow Index in Optical Coherence Tomography Angiography Provides a Sensitive Biomarker of Early Diabetic Retinopathy

Purpose

To evaluate the sensitivity of normalized blood flow index (NBFI) for detecting early diabetic retinopathy (DR).

Methods

Optical coherence tomography angiography (OCTA) images of healthy controls, diabetic patients without DR (NoDR), and patients with mild nonproliferative DR (NPDR) were analyzed in this study. The OCTA images were centered on the fovea and covered a 6 mm × 6 mm area. Enface projections of the superficial vascular plexus (SVP) and the deep capillary plexus (DCP) were obtained for the quantitative OCTA feature analysis. Three quantitative OCTA features were examined: blood vessel density (BVD), blood flow flux (BFF), and NBFI. Each feature was calculated from both the SVP and DCP and their sensitivities to distinguish the three cohorts of the study were evaluated.

Results

The only quantitative feature capable of distinguishing all three cohorts was NBFI in the DCP image. Comparative study revealed that both BVD and BFF were able to distinguish the controls and NoDR from mild NPDR. However, neither BVD nor BFF was sensitive enough to separate NoDR from the healthy controls.

Conclusions

The NBFI has been demonstrated as a sensitive biomarker of early DR, revealing retinal blood flow abnormality better than traditional BVD and BFF. The NBFI in the DCP was verified as the most sensitive biomarker, supporting that diabetes affects the DCP earlier than SVP in DR.

Translational Relevance

NBFI provides a robust biomarker for quantitative analysis of DR-caused blood flow abnormalities, promising early detection and objective classification of DR.

The cGAS-STING pathway in diabetic retinopathy and age-related macular degeneration

Diabetic retinopathy and age-related macular degeneration are common retinal diseases with shared pathophysiology, including oxidative stress-induced inflammation. Cellular mechanisms responsible for converting oxidative stress into retinal damage are ill-defined but have begun to clarify. One common outcome of retinal oxidative stress is mitochondrial damage and subsequent release of mitochondrial DNA into the cytosol. This leads to activation of the cGAS-STING pathway, resulting in interferon release and disease-amplifying inflammation. This review summarizes the evolving link between aberrant cGAS-STING signaling and inflammation in common retinal diseases and provides prospective for targeting this system in diabetic retinopathy and age-related macular degeneration. Further defining the roles of this system in the retina is expected to reveal new disease pathology and novel therapeutic approaches.

hsa_circ_0000047 targeting miR-6720-5p/CYB5R2 axis alleviates inflammation and angiogenesis in diabetic retinopathy

Context: Diabetic retinopathy (DR) is a common complication of diabetes mellitus (DM). Circular RNAs (circRNAs) act as key regulators of DR development by regulating inflammation and angiogenesis.Objective: This study aimed to elucidate the function and mechanism of hsa_circ_0000047 in DR.Materials and methods: High glucose (HG) was used to induce human retinal microvascular endothelial cells (hRMECs) to construct a DR model in vitro. Qualitative real-time polymerase chain reaction (qRT-PCR) or western blotting were used to detected the levels of hsa_circ_0000047, miR-6720-5p, and CYB5R2 in DR and HG-indeced hRMECs. Cell functional experiments were performed to detect the change of viability, inflammation, migration, invasion, and angiogenesis of HG-induced hRMECs. Besides, the correlation between miR-6720-5p and hsa_circ_0000047/CYB5R2 was confirmed by luciferase assay and Pearson correlation analysis.Results: hsa_circ_0000047 and CYB5R2 were downregulated in DR, whereas miR-6720-5p was upregulated in DR. Cell functional experiments showed that hsa_circ_0000047 overexpression restrained viability, inflammation, migration, invasion, and angiogenesis of HG-induced hRMECs. Regarding mechanism, hsa_circ_0000047 could sponge miR-6720-5p to regulate CYB5R2 expression in hRMECs. Additionally, CYB5R2 knockdown reversed the effects of hsa_circ_0000047 overexpression on HG-induced hRMECs.Conclusion: Our study revealed that hsa_circ_0000047 alleviated inflammation and angiogenesis in HG-induced hRMECs by targeting the miR-6720-5p/CYB5R2 axis, which may be a novel biomarker for DR therapy.

Therapeutic effects of herbal medicines in different types of retinopathies: A systematic review

Objective

Retinopathy is an ocular manifestation of systemic diseases such as diabetes and vascular diseases. Herbal drugs have been considered as an effective therapeutic option with minimal side effects for the treatment of retinopathy by reducing the symptoms and improving visual acuity. The purpose of this systematic review was to collect studies on the effectiveness of medicinal plants in the treatment or prevention of retinopathy.

Materials and Methods

A systematic literature search was performed in PubMed, Scopus, Google Scholar, and other databases in April 2021 using "herbal products" and "Retinopathy" with all their equivalent and similar terms. For this purpose, human clinical trials with the English language were included and articles with subject irrelevancy were excluded from further evaluation.

Results

Overall, 30 articles with 2324 patients were studied for possible effects of herbal therapy on retinopathy. From 30 included articles, different herbal products had been evaluated. Out of 30 selected articles, 11 articles were for the treatment of age-related macular degeneration (AMD), 14 articles covered patients with diabetic retinopathy, and the other five studies were for other retinal disorders. The outcomes in majority of the studies include changes in visual acuity (VA), fundus performance, best-corrected visual acuity (BCVA), central macular thickness (CMT), focal electroretinogram (fERG), supplements and adjuvant medications appeared to be more beneficial in patients with AMD and diabetic maculopathy.

Conclusion

Herbal therapy can be considered as a potential candidate in the adjuvant and complementary therapies of retinopathy. However, further studies are required to verify such efficiency.

Can the Future be Bright with Advances in Diabetic Eye Care?

The prevalence of diabetic retinopathy is steadily increasing as the population of patients with diabetes grows. In the past decade, the development of anti-VEGF agents has dramatically changed the treatment landscape for diabetic retinopathy and diabetic macular edema (DME). Newer agents in development aim to reduce the treatment burden of diabetic retinopathy.

Experimental Models to Study Epithelial-Mesenchymal Transition in Proliferative Vitreoretinopathy

Proliferative vitreoretinal diseases (PVDs) encompass proliferative vitreoretinopathy (PVR), epiretinal membranes, and proliferative diabetic retinopathy. These vision-threatening diseases are characterized by the development of proliferative membranes above, within and/or below the retina following epithelial-mesenchymal transition (EMT) of the retinal pigment epithelium (RPE) and/or endothelial-mesenchymal transition of endothelial cells. As surgical peeling of PVD membranes remains the sole therapeutic option for patients, development of in vitro and in vivo models has become essential to better understand PVD pathogenesis and identify potential therapeutic targets. The in vitro models range from immortalized cell lines to human pluripotent stem-cell-derived RPE and primary cells subjected to various treatments to induce EMT and mimic PVD. In vivo PVR animal models using rabbit, mouse, rat, and swine have mainly been obtained through surgical means to mimic ocular trauma and retinal detachment, and through intravitreal injection of cells or enzymes to induce EMT and investigate cell proliferation and invasion. This review offers a comprehensive overview of the usefulness, advantages, and limitations of the current models available to investigate EMT in PVD.