Ocular complications of diabetes mellitus

Retinal vessel tortuosity and fractal dimension in diabetic retinopathy

BACKGROUND

Retinal vessel geometry characteristic have been studied as one of the signs of microvascular changes in diabetic retinopathy (DR) that necessitates early screening. This study aimed to investigate the differences in retinal vessel tortuosity (VT) and fractal dimension (FD) between patients with and without DR.

METHODS

This retrospective study analyzed medical records and OCT-A images of DR and No-DR patients. DR severity was graded by a vitreoretinal specialist following the International Clinical Diabetic Retinopathy and Diabetic Macular Edema Severity Scales. Retinal VT and FD were quantified using ImageJ software. Comparison between groups using non-parametric and Generalized Estimating Equations (GEE) statistical analysis combined with cluster bootstrapping.

RESULTS

We analyzed 96 (161 eyes) with the mean age of 52.7 ± 9.9 years. Compared to No-DR, VT was significantly higher in all DR groups (p < 0.05). Mild non proliferative DR (β = +0.0621), Moderate NPDR (β = +0.0412), Severe NPDR (β = +0.0441), and proliferative DR (β = +0.0404). FD of the superficial capillary plexus (SCP) showed no significant difference among the groups and a significantly lower FD of the deep capillary plexus (DCP) compared to the No-DR groups (moderate NPDR (β = -0.0131), severe NPDR ( β = -0.0316) and PDR ( β = -0.0326)).

CONCLUSION

Compared to No-DR group, VT was found significantly higher in DR group, and FD of the DCP found significantly lower in the DR group. These parameters offer unique insights beyond simple vessel loss and complementary information into the geometric complexity and structural alterations of the retinal microvasculature in DR.

Performance and Effectiveness of Diabetic Retinopathy Screening in Portugal: An Outcome-Based Evaluation

Background/Objectives: Diabetic retinopathy (DR) is the leading cause of preventable blindness among working-age adults. Early detection through screening programs is essential for managing the condition and preventing visual impairment. In Portugal, the national DR screening program (DR SP) targets diabetic patients, aiming to detect DR at an early stage and refer patients requiring intervention for an ophthalmology appointment. This study aims to assess the effectiveness of the Portuguese DR SP by analyzing patients referred for a hospital appointment following a positive screening result. Methods: An observational retrospective cohort study was conducted at Unidade Local de Saúde de São João (ULS-SJ), including patients referred to a DR SP hospital appointment between January 2020 and December 2023. Data were collected from hospital records upon approval by the Hospital Ethics Committee. Screening and hospital diagnoses were compared for agreement. The Chi-Square test and Cohen's Kappa were used to assess the association between screening and hospital diagnoses. Results: A total of 1126 patients (2251 retinographies) were analyzed. The median time from screening to hospital consultation was 63 days (Interquartile Range = 39-99), though referral times varied widely within the same classifications (ranging from 8 to 354 days). The most common screening classifications were R2 (pre-proliferative DR, 47.8%) and M1 (maculopathy, 24.6%). In eyes with DR, agreement between screening and hospital diagnoses was highest for R2 (40.1%) and M1 (32.3%), while proliferative DR (R3) showed 30% agreement. The positive predictive value (PPV) of the screening program was 55.9%, with a false positive rate of 44.1%. A statistically significant association between screening and hospital diagnoses was observed (p < 0.001, Chi-Square test), though Cohen's Kappa values (0.167 Right Eye, 0.157 Left eye) indicated only slight agreement. Conclusions: Our study found that DR SP effectively identifies patients needing ophthalmologic evaluation with moderate diagnostic agreement and a relatively high false positive rate, leading to unnecessary referrals. While this ensures that sight-threatening cases are not missed, improvements in grader training, classification protocols, and Optical Coherence Tomography (OCT) integration could improve results. Strengthening screening adherence and optimizing referral pathways would further improve the program's impact on early DR detection and management.

The Role and Diagnostic Potential of Insulin-like Growth Factor 1 in Diabetic Retinopathy and Diabetic Macular Edema

Diabetes mellitus (DM) is a chronic metabolic disorder that results in hyperglycemia, leading to multiple microvascular and macrovascular complications, including significant ocular damage resulting in the development of diabetic retinopathy (DR) and diabetic macular edema (DME). Many factors contribute to the pathogenesis of DR and DME, including hyperglycemia-mediated vascular and neuronal abnormalities and local and systemic inflammation. Growth hormone (GH) and insulin-like growth factor-1 (IGF-1) have been implicated in the initiation and progression of DR and DME through a variety of mechanistic processes. In this review, we provide a comprehensive synopsis of the diverse roles and molecular pathways supporting IGF-1 in the pathogenesis of DR and DME, elucidating its range of effects from detrimental to protective, depending on the context and stage of disease. We further investigate the underlying inflammatory processes regulated by IGF-1 and examine how the interaction of IGF-1 with key signaling molecules influences these inflammatory mechanisms. Additionally, the potential of serum IGF-1 as a biomarker for the progression of DR and DME in clinical practice is discussed. Finally, we consider current therapeutic approaches for DR and DME in relation to IGF-1 and explore novel therapeutic targets and innovative delivery methods. By providing an in-depth understanding of IGF-1's role in the pathogenesis and progression of DR and DME, this review underscores the diagnostic utility of serum IGF-1 and puts forth new treatment strategies to improve the management of DR and DME.

Risk factors for self-reports of diagnosed cataracts among older adults in Poland

PURPOSE

The aim of our study was to investigate sociodemographic factors, comorbidities and health behaviors associated with self-reported diagnosed cataracts in a large, nationally representative population of older adults in Poland, aged 60 and older.

PATIENT AND METHODS

An analysis was conducted using a survey of 5956 participants in the nationally representative PolSenior2 study conducted between 2018 and 2019. Multiple logistic regression analysis was used to evaluate the associations between self-reports of diagnosed cataracts and sociodemographic factors, health behaviors, and comorbidities.

RESULTS

According to the final multivariable model, the odds ratio (OR) of self-reported cataract diagnosis was 1.71 times greater for women than for men. Additionally, the odds increased significantly with age, with 70-79-year-olds having 3.38 times greater odds, 80-89-year-olds having 8.08 times greater odds, and those aged 90 years and older having 10.76 times greater odds than did the reference group (60-69 years old). The prevalence of self-reported diagnosed cataracts was found to be 1.47 times greater among individuals with diabetes, 1.20 times greater among those with hypertension, and 1.25 times greater among tobacco users than among their respective counterparts. Additionally, rural dwellers exhibited a lower risk of self-reported cataracts (OR = 0.63).

CONCLUSION

Our study revealed a positive relationship between several demographic and health factors-namely, older age, female sex, urban residence, hypertension, diabetes, and smoking-and an elevated risk of self-reports of diagnosed cataracts.

Biosynthesis of gold nanoparticles and their protective effect towards diabetic nephropathy by inhibition of oxidative stress

BACKGROUND

Diabetes is an emerging health issue on a global scale, with increasing prevalence rates reported in many countries. Many mechanisms are proposed for diabetic nephropathy, with oxidative stress being the most significant. The effectiveness of gold nanoparticles (AuNPs) in the attenuation of nephropathy and oxidative stress in diabetic mice was assessed in this study.

OBJECTIVE

The aim of this study is to synthesize AuNPs and assess their protective effect towards diabetic nephropathy by inhibition of oxidative stress.

METHODS

The aqueous extract of Allium sativum was employed to synthesize AuNPs. The prepared AuNPs were characterized using a variety of microscopic and spectroscopic techniques. In-vitro studies were conducted using mice. Streptozotocin (STZ) was employed to induce diabetes in rodents. After 7 days of administration of STZ, anesthesia was given to all animals and blood was collected for the assessment of creatinine and Blood Urea Nitrogen (BUN) levels. Later, kidney tissue was removed at 4 °C and changes in pathology and oxidative stress were assessed.

RESULTS

Nephropathy was confirmed in diabetic mice by the changes in the pathology of kidney tissue along with significant rise in the plasma levels of BUN and creatinine. Additionally, the peroxidation of lipids, formation of Reactive Oxygen Species (ROS), oxidation of glutathione (GSH), concentration of carbonyl protein was also increased in the tissue of kidney of diabetic mice. Oxidative stress in kidney tissue and changes in the pathology of diabetic mice were inhibited significantly (p < 0.05) with the treatment of AuNPs.

CONCLUSION

This study revealed the protective effects of AuNPs over diabetic nephropathy by inhibiting the pathway of oxidative stress. Since, the prepared AuNPs showed improvement over complications of diabetes, they may be believed as a potential gratuitous treatment next to other drugs for reducing blood glucose.

Diabetes and Cataracts Development-Characteristics, Subtypes and Predictive Modeling Using Machine Learning in Romanian Patients: A Cross-Sectional Study

Background and Objectives: Diabetes has become a global epidemic, contributing to significant health challenges due to its complications. Among these, diabetes can affect sight through various mechanisms, emphasizing the importance of early identification and management of vision-threatening conditions in diabetic patients. Changes in the crystalline lens caused by diabetes may lead to temporary and permanent visual impairment. Since individuals with diabetes are at an increased risk of developing cataracts, which significantly affects their quality of life, this study aims to identify the most common cataract subtypes in diabetic patients, highlighting the need for proactive screening and early intervention. Materials and Methods: This study included 201 participants with cataracts (47.6% women and 52.4% men), of whom 105 also had diabetes. With the use of machine learning, the patients were assessed and categorized as having one of the three main types of cataracts: cortical (CC), nuclear (NS), and posterior subcapsular (PSC). A Random Forest Classification algorithm was employed to predict the incidence of different associations of cataracts (1, 2, or 3 types). Results: Cataracts have been encountered more frequently and at a younger age in patients with diabetes. CC was significantly more frequent among patients with diabetes (p < 0.0001), while the NS and PSC were only marginally, without statistical significance. Machine learning could also contribute to an early diagnosis of cataracts, with the presence of diabetes, duration of diabetes, or diabetic polyneuropathy (PND) having the highest importance for a successful classification. Conclusions: These findings suggest that diabetes may impact the type of cataract that develops, with CC being notably more prevalent in diabetic patients. This has important implications for screening and management strategies for cataract formation in diabetic populations.

Citicoline eluting hydrogels for therapeutic contact lenses intended to treat neurodegenerative diabetic ocular diseases

Ophthalmic neurodegenerative diseases related to diabetes, such as glaucoma and retinopathy, are among the major causes of blindness in the world. Citicoline (CIT) in the form of eye drops is currently used for the treatment/prevention of these diseases, which affect the posterior segment of the eye. To ensure the drug penetration into the back of the eye, frequent instillations of highly concentrated drug solutions are required with potential side effects. Drug-loaded soft contact lenses (SCLs) may be an effective alternative to the conventional eye drop treatment, since they may enable a sustained drug release during daily wear, ensuring a higher drug bioavailability, and avoiding drug waste. In this work, one 2-hydroxyethyl methacrylate (HEMA) based hydrogel was functionalised with N-(3-aminopropyl) methacrylamide hydrochloride (APMA), molecularly imprinted with CIT and loaded with the same drug. The material was extensively characterised, in terms of morphology, optical, mechanical, and physical-chemical properties, namely, equilibrium water content, wettability, oxygen and ionic permeability, Young's modulus, shear deformation, transmittance and refractive index, before and after steam sterilisation. Additionally, the tendency of the material to adsorb proteins of the lachrymal fluid was evaluated and its biocompatibility was assessed by irritation and cytotoxicity assays. Comparison with the non-functionalised and non-imprinted hydrogel showed that the modified hydrogel led to a sustained in vitro release of a much higher amount of CIT than the original one, while keeping typical values for physical-chemical properties of SCLs. The drug-loaded material resisted steam sterilisation and proved to be biocompatible, demonstrating adequate properties to be used in therapeutic SCLs for the prophylaxis/treatment of neurodegenerative diabetic ocular diseases. The neuroprotective effect of the released drug was confirmed with tests using porcine retinal explants.

Availability and affordability of diabetes healthcare services associated with the frequency of diabetes-related complications

AIMS

Understanding the healthcare access challenges facing diabetic patients in low- and middle-income countries is very important. The present study investigated the association between availability (physical access) and affordability (economic access) to diabetes healthcare services and the frequency of diabetes-related complications.

METHODS

A cross-sectional survey study was conducted between February and May 2023 in Qazvin, Iran. Using convenience sampling, 373 type 2 diabetic patients (mean age = 57.99 years; SD = 11.71) referred to diabetic specialists' clinics were surveyed. Demographic characteristics, physical access to diabetes healthcare services, economic access to diabetes healthcare services, and frequency of diabetes-related complications (FDRCs) were assessed. Data were assessed using linear regression analysis.

RESULTS

The mean total access score to healthcare services was 17.71 (out of 30; SD ± 4.21; range 6-30). Patients who had more access to healthcare services had less diabetes-related complications (p < 0.005). There was a significant negative correlation (p < 0.01) between FDRCs and (i) physical access to diabetes-related healthcare services (r = -0.166) and (ii) economic access to diabetes-related healthcare services (r = -0.153). Linear regression analysis showed that with each unit increase in participants' economic, physical and total access to diabetes-related healthcare services, the FDRCs among participants decreased by 8.7%, 13.5%, and 8.8% respectively.

CONCLUSION

The results indicate that increased physical accessibility (availability) and economic accessibility (affordability) of healthcare services are associated with fewer diabetes-related complications. Therefore, policymakers and healthcare managers need to reduce diabetes-related complications by implementing schemes to increase patient access to diabetes treatment services.

Specular microscopy findings in diabetic patients: a systematic review and meta-analysis

OBJECTIVE

To evaluate the specular microscopy findings in patients with diabetes mellitus (DM) through a systematic review and meta-analysis.

METHODS

A systematic search with the appropriate keyword was done in the online databases including PubMed, Scopus, and Web of Sciences. The records were imported into EndNote software and duplicated records were removed. The title, abstract, and full text of the articles were evaluated carefully. STATA software also was used for all data analyses. The mean difference (MD) and 95% confidence intervals (95% CIs) were used to examine the data.

RESULTS

After a systematic search, 781 records were evaluated and finally, 14 of them were selected for final analysis. The results showed that the mean differences in average cell size (MD = 21.22, 95% CI 10.43, 32.01, P 0.001), central corneal thickness (MD = 9.90, 95% CI 6.07, 13.73, P 0.001), and coefficient of variation (MD = 1.11, 95% CI 0.11, 2.11, P = 0.03) were higher in diabetic patients in comparison with healthy cases. However, the mean differences in endothelial cell density (MD = -114.29, 95% CI -158.34, -70.24, P 0.001) and hexagonal cell ratio (MD = -3.52, 95% CI -5.79, -1.25, P < 0.001) were lower in diabetic cases.

CONCLUSIONS

Patients with DM have higher average cell size, corneal thickness, and coefficient of variation. On the other hand, the endothelial cell density and hexagonal cell ratio were reduced in diabetic cases.

The Effectiveness of Steroid Versus Vitamin Therapy in the Improvement of Extraocular Movements in Patients With Diabetic Cranial Nerve Palsy: A Comparative Study

BACKGROUND

 Diabetic mononeuropathies, which are focal neuropathies, are less common than peripheral neuropathy in diabetes. They are frequently underreported or misdiagnosed due to mild or unnoticed cases. Early detection and treatment are crucial to prevent worsening nerve damage and complications.

OBJECTIVES

This study aims to compare the effectiveness of conventional treatment with vitamin therapy for improving these neuropathies.

METHODS

Fifty cases of diabetic ocular nerve palsy were stratified into two groups, 25 in each. Group A received steroids, while group B received vitamin B12 injections. Ocular movements were assessed before and after treatment initiation at 3, 6, and 10 days using the Kestenbaum limbus test. Inferential statistics were done using the chi-square test and the student t-test.

RESULTS

The average age of the participants in the study was 60.5 ± 6.3 years. Thirty-eight patients had sixth nerve palsy, and 12 patients had associated third nerve palsy. Thirty-eight subjects had poorly controlled diabetes. The mean enhancement in movements was 0.75 ± 0.3 in group A and 1.04 ± 0.5 in group B, with a p value of 0.026, demonstrating the statistically significant difference between both groups.

CONCLUSION

This study infers that the ocular movements were significantly improved with vitamin therapy. Treating diabetic neuropathy solely with vitamin supplementation indirectly addresses nutritional deficiencies, potentially accelerating diabetes-related complications and enhancing quality of life.

Risk Factors for Cataracts in Patients with Diabetes Mellitus

Background: Diabetes mellitus (DM) is one of the most impactful health problems worldwide. It affects ocular health in multiple ways and is one of the leading causes of vision loss. Our study aimed to evaluate the most important systemic risk factors related to the occurrence of cataracts in patients with DM. Method: This study evaluated a final number of 319 participants who were previously diagnosed with DM. For all patients, we retrieved data regarding DM status, metabolic control, demographic and anthropometric indices, and generally associated comorbidities from their medical charts. A comprehensive eye examination was performed on all patients. Results: The main studied risk factors were hypertension, cardiovascular disease (CVD), chronic kidney disease (CKD), diabetic polyneuropathy (DPN), dyslipidemia, and hepatic steatosis, which were present among the entire population. Hypertension (67.6%), DPN (53.3%), and dyslipidemia (46.6%) were highly prevalent in the cataract subgroup, and CKD (p < 0.001) and DPN (p = 0.019) were found to be predictive factors for the probability of cataract occurrence. Ophthalmologic evaluation was used to assess the presence of ocular complications, such as diabetic retinopathy (DR) and diabetic maculopathy. DR reached statistically significant values in the occurence of cataracts. Patients' age and DM-related factors, such as disease duration (p < 0.001) and HbA1c values (p = 0.029), significantly increased the risk of cataracts. Smoking was self-reported by 24.8% of the patients, with a significant impact on the occurrence of cataracts (p = 0.04). Conclusions: Patients with DM who exhibit a longer disease duration and poor glycemic control in conjunction with systemic comorbidities present a higher risk of developing cataracts; consequently, a strict therapeutic approach regarding these risk factors is needed.

A Neuron-Mast Cell Axis Regulates Skin Microcirculation in Diabetes

Changes in microcirculation lead to the progression of organ pathology in diabetes. Although neuroimmune interactions contribute to a variety of conditions, it is still unclear whether abnormal neural activities affect microcirculation related to diabetes. Using laser speckle contrast imaging, we examined the skin of patients with type 2 diabetes and found that their microvascular perfusion was significantly compromised. This phenomenon was replicated in a high-fat diet-driven murine model of type 2 diabetes-like disease. In this setting, although both macrophages and mast cells were enriched in the skin, only mast cells and associated degranulation were critically required for the microvascular impairment. Sensory neurons exhibited enhanced TRPV1 activities, which triggered mast cells to degranulate and compromise skin microcirculation. Chemical and genetic ablation of TRPV1+ nociceptors robustly improved skin microcirculation status. Substance P (SP) is a neuropeptide and was elevated in the skin and sensory neurons in the context of type 2 diabetes. Exogenous administration of SP resulted in impaired skin microcirculation, whereas neuronal knockdown of SP dramatically prevented mast cell degranulation and consequently improved skin microcirculation. Overall, our findings indicate a neuron-mast cell axis underlying skin microcirculation disturbance in diabetes and shed light on neuroimmune therapeutics for diabetes-related complications.

ARTICLE HIGHLIGHTS

Reduction of pathological retinal neovascularization, vessel obliteration, and artery tortuosity by PEDF protein in an oxygen-induced ischemic retinopathy rat model

Retinopathy of prematurity (ROP) is a severe retinal disease in premature infants characterized by pathological neovascularization, obliteration of retinal vessels and increased vessel tortuosity. Currently, there are no completely satisfactory treatments for ROP. Pigment epithelium-derived factor (PEDF), a potent inhibitor of angiogenesis, appears late in gestation and its deficiency may be linked to development of ROP. This study investigates the preclinical efficacy of PEDF protein alone or in combination with VEGF antagonists for treating ROP. The safety of PEDF protein in the rat eye was assessed using functional in vivo measurements and histology. The efficacy of intravitreal injections (IVI) of various treatments was evaluated in a rat oxygen-induced retinopathy (OIR) model using in vivo imaging and flatmount analyses. No functional or histological side-effects were found in rat eyes after intravitreal PEDF protein injection. PEDF protein alone or combined with anti-VEGF drugs significantly reduced pathological neovascularization and vessel obliteration, comparable to the effects of anti-VEGF drugs alone. Regarding arterial tortuosity, treatment with a combination of PEDF, and VEGF antagonist was more effective than treatment with anti-VEGF alone. IVI of PEDF protein is safe. PEDF protein alone or combined with VEGF antagonists shows similar efficacy in reducing pathological neovascularization and vessel obliteration as anti-VEGF agents. Furthermore, only treatments involving PEDF protein, alone or with VEGF antagonists, significantly improved the quality of retinal vasculature. Thus, PEDF protein alone or combined with anti-VEGF agents presents a promising alternative to current anti-VEGF treatments for ROP.

Ocular Manifestations in Seborrheic Dermatitis Epidemiology, Clinical Features, and Management: A Comprehensive Review

Seborrheic dermatitis (SD) often leads to ocular manifestations (OM) that are frequently overlooked. This study comprehensively explains the genesis of these ocular issues, which involves a combination of Malassezia overgrowth, changes in sebum production, and inflammatory responses in the body. The periocular region is rich in sebaceous glands, allowing Malassezia to thrive, which can lead to an inflammatory reaction that spreads to the eye surface, causing disorders such as blepharitis, conjunctivitis, keratitis, and ocular surface diseases. Although epidemiological data are limited, it is well established that ocular involvement occurs in approximately 10%-40% of individuals with SD. Early detection and treatment are crucial to prevent potential vision-threatening complications. A comprehensive diagnostic approach is necessary, including clinical examination, slit-lamp biomicroscopy, tear film analysis, and corneal imaging. Managing these conditions requires a multidisciplinary strategy involving collaboration between dermatologists and ophthalmologists. The treatment should involve topical and systemic medications to address the skin and ocular components. Patient education is critical for improving adherence to therapy, self-management, and the early identification of problems. In the future, it will be essential to investigate the intricate interactions between Malassezia species and host immunological processes. This collective effort will involve creating new biomarkers and diagnostic tools, investigating targeted immunomodulatory drugs and novel lipid-based medicines as potential treatments, and conducting large-scale longitudinal studies to understand the epidemiological patterns and prognostic variables better. By raising awareness, encouraging collaboration across disciplines, and advancing research, healthcare practitioners can significantly improve patients' quality of life with SD and OM.

Evaluation of Systemic Risk Factors in Patients with Diabetes Mellitus for Detecting Diabetic Retinopathy with Random Forest Classification Model

BACKGROUND

This study aims to assess systemic risk factors in diabetes mellitus (DM) patients and predict diabetic retinopathy (DR) using a Random Forest (RF) classification model.

METHODS

We included DM patients presenting to the retina clinic for first-time DR screening. Data on age, gender, diabetes type, treatment history, DM control status, family history, pregnancy history, and systemic comorbidities were collected. DR and sight-threatening DR (STDR) were diagnosed via a dilated fundus examination. The dataset was split 80:20 into training and testing sets. The RF model was trained to detect DR and STDR separately, and its performance was evaluated using misclassification rates, sensitivity, and specificity.

RESULTS

Data from 1416 DM patients were analyzed. The RF model was trained on 1132 (80%) patients. The misclassification rates were 0% for DR and ~20% for STDR in the training set. External testing on 284 (20%) patients showed 100% accuracy, sensitivity, and specificity for DR detection. For STDR, the model achieved 76% (95% CI-70.7%-80.7%) accuracy, 53% (95% CI-39.2%-66.6%) sensitivity, and 80% (95% CI-74.6%-84.7%) specificity.

CONCLUSIONS

The RF model effectively predicts DR in DM patients using systemic risk factors, potentially reducing unnecessary referrals for DR screening. However, further validation with diverse datasets is necessary to establish its reliability for clinical use.

Phacoemulsification Techniques and Their Effects on Corneal Endothelial Cells and Visual Acuity: A Review of "Direct-Chop" and "Stop-and-Chop" Approaches Under Topical Anesthesia

Phacoemulsification is a widely adopted technique in cataract surgery that offers a minimally invasive approach to lens removal and intraocular lens implantation. Among the various methods of phacoemulsification, "direct-chop" and "stop-and-chop" techniques are particularly notable for their efficiency and safety profiles. This review aims to evaluate the effects of these two techniques on corneal endothelial cells and visual acuity, specifically under topical anesthesia. Cataract surgery outcomes hinge on the preservation of corneal endothelial cells and the achievement of optimal visual acuity. Endothelial cell loss can lead to corneal decompensation, while visual acuity is a primary measure of surgical success. The "direct-chop" technique involves the immediate chopping of the lens nucleus after groove creation, reducing phacoemulsification time and energy. Conversely, the "stop-and-chop" technique incorporates a central groove before chopping, offering increased control and safety. This review synthesizes current research and clinical studies to compare these techniques, focusing on their respective impacts on endothelial cell count and postoperative visual acuity. It examines the advantages and disadvantages of each approach, considers the role of surgeon experience, phacoemulsification energy, and anterior chamber stability, and assesses patient outcomes under topical anesthesia. The findings aim to provide insights that can guide surgeons in selecting the most appropriate technique for their patients, ultimately enhancing surgical outcomes by ensuring the preservation of corneal health and the achievement of superior visual acuity.

Recent updates on ocular disease management with ophthalmic ointments

Ophthalmic diseases can result in permanent vision loss and blindness. Convenient topical and systemic treatments are preferred to address these sight-threatening conditions. However, the unique anatomy of the eye presents challenges for drug delivery. Various ophthalmic ointment formulations have been developed to enhance bioavailability in the eye to prolong residence time and improve corneal permeability. This article explores a wide range of ocular diseases affecting individuals globally and how ointments are used to manage them. From eye to ocular barriers, this review focuses on published scientific research and formulation strategies for severe ocular complications using conventional topical ointments. Additionally, it delves through patented technologies and marketed formulations supporting the use of ointments in ocular drug delivery.

Plasma miR-19b, miR-34a, and miR-146a expression in patients with type 2 diabetes mellitus and cataract: A pilot study

Cataract is among the most common ocular complications in diabetes mellitus (DM). While microRNA (miRNA) dysregulations in DM have been previously reported, consensus is still lacking concerning miRNA expression in cataract. Furthermore, the miRNA profile in diabetic cataract patients remains largely unexplored, and data on plasma expression levels are limited. Our study aimed to assess the plasma levels of three distinct miRNA species (hsa-miR-19b, hsa-miR-34a, and hsa-miR-146a) implicated in the development of cataract and/or DM.We investigated the circulating miRNA expression in DM patients diagnosed with cataract, compared to a non-DM cataract group. We employed qRT-PCR for relative quantification experiments and subsequently conducted a correlation analysis between miRNA expression levels and clinical characteristics. Our findings reveal that hsa-miR-34a and hsa-miR-146a are differentially expressed in the two cohorts. However, no significant correlation was observed between the clinical variables and miRNA levels. In summary, our results suggest a potential role for hsa-miR-34a and hsa-miR-146a in the biology of diabetic cataract.

Extracellular Vesicles Isolated from Equine Adipose-Derived Stromal Stem Cells (ASCs) Mitigate Tunicamycin-Induced ER Stress in Equine Corneal Stromal Stem Cells (CSSCs)

Corneal ulcers, characterized by severe inflammation of the cornea, can lead to serious, debilitating complications and may be vision-threatening for horses. In this study, we aimed to investigate the role of endoplasmic reticulum (ER) stress in corneal stem progenitor cell (CSSC) dysfunction and explore the potential of equine adipose-derived stromal stem cell (ASC)-derived extracellular vesicles (EVs) to improve corneal wound healing. We showed that CSSCs expressed high levels of CD44, CD45, and CD90 surface markers, indicating their stemness. Supplementation of the ER-stress-inducer tunicamycin to CSSCs resulted in reduced proliferative and migratory potential, accumulation of endoplasmic reticulum (ER)-stressed cells in the G0/G1 phase of the cell cycle, increased expression of proinflammatory genes, induced oxidative stress and sustained ER stress, and unfolded protein response (UPR). Importantly, treatment with EVs increased the proliferative activity and number of cells in the G2/Mitosis phase, enhanced migratory ability, suppressed the overexpression of proinflammatory cytokines, and upregulated the anti-inflammatory miRNA-146a-5p, compared to control and/or ER-stressed cells. Additionally, EVs lowered the expression of ER-stress master regulators and effectors (PERK, IRE1, ATF6, and XBP1), increased the number of mitochondria, and reduced the expression of Fis-1 and Parkin, thereby promoting metabolic homeostasis and protecting against apoptosis in equine CSSCs. Our findings demonstrate that MSCs-derived EVs represent an innovative and promising therapeutic strategy for the transfer of bioactive mediators which regulate various cellular and molecular signaling pathways.

Effects of Diabetes Mellitus on Corneal Immune Cell Activation and the Development of Keratopathy

Diabetes mellitus (DM) is one of the most prevalent diseases globally, and its prevalence is rapidly increasing. Most patients with a long-term history of DM present with some degree of keratopathy (DK). Despite its high incidence, the underlying inflammatory mechanism of DK has not been elucidated yet. For further insights into the underlying immunopathologic processes, we utilized streptozotocin-induced mice to model type 1 DM (T1D) and B6.Cg-Lepob/J mice to model type 2 DM (T2D). We evaluated the animals for the development of clinical manifestations of DK. Four weeks post-induction, the total frequencies of corneal CD45+CD11b+Ly-6G- myeloid cells, with enhanced gene and protein expression levels for the proinflammatory cytokines TNF-α and IL-1β, were higher in both T1D and T2D animals. Additionally, the frequencies of myeloid cells/mm2 in the sub-basal neural plexus (SBNP) were significantly higher in T1D and T2D compared to non-diabetic mice. DK clinical manifestations were observed four weeks post-induction, including significantly lower tear production, corneal sensitivity, and epitheliopathy. Nerve density in the SBNP and intraepithelial terminal endings per 40x field were lower in both models compared to the normal controls. The findings of this study indicate that DM alters the immune quiescent state of the cornea during disease onset, which may be associated with the progressive development of the clinical manifestations of DK.

Recommendations for diabetic macular edema management by retina specialists and large language model-based artificial intelligence platforms

PURPOSE

To study the role of artificial intelligence (AI) in developing diabetic macular edema (DME) management recommendations by creating and comparing responses to clinicians in hypothetical AI-generated case scenarios. The study also examined whether its joint recommendations followed national DME management guidelines.

METHODS

The AI hypothetically generated 50 ocular case scenarios from 25 patients using keywords like age, gender, type, duration and control of diabetes, visual acuity, lens status, retinopathy stage, coexisting ocular and systemic co-morbidities, and DME-related retinal imaging findings. For DME and ocular co-morbidity management, we calculated inter-rater agreements (kappa analysis) separately for clinician responses, AI-platforms, and the "majority clinician response" (the maximum number of identical clinician responses) and "majority AI-platform" (the maximum number of identical AI responses). Treatment recommendations for various situations were compared to the Indian national guidelines.

RESULTS

For DME management, clinicians (ĸ=0.6), AI platforms (ĸ=0.58), and the 'majority clinician response' and 'majority AI response' (ĸ=0.69) had moderate to substantial inter-rate agreement. The study showed fair to substantial agreement for ocular co-morbidity management between clinicians (ĸ=0.8), AI platforms (ĸ=0.36), and the 'majority clinician response' and 'majority AI response' (ĸ=0.49). Many of the current study's recommendations and national clinical guidelines agreed and disagreed. When treating center-involving DME with very good visual acuity, lattice degeneration, renal disease, anaemia, and a recent history of cardiovascular disease, there were clear disagreements.

CONCLUSION

For the first time, this study recommends DME management using large language model-based generative AI. The study's findings could guide in revising the global DME management guidelines.

Rat Model of Type 2 Diabetes Mellitus Recapitulates Human Disease in the Anterior Segment of the Eye

Changes in the anterior segment of the eye due to type 2 diabetes mellitus (T2DM) are not well-characterized, in part due to the lack of a reliable animal model. This study evaluates changes in the anterior segment, including crystalline lens health, corneal endothelial cell density, aqueous humor metabolites, and ciliary body vasculature, in a rat model of T2DM compared with human eyes. Male Sprague-Dawley rats were fed a high-fat diet (45% fat) or normal diet, and rats fed the high-fat diet were injected with streptozotocin i.p. to generate a model of T2DM. Cataract formation and corneal endothelial cell density were assessed using microscopic analysis. Diabetes-related rat aqueous humor alterations were assessed using metabolomics screening. Transmission electron microscopy was used to assess qualitative ultrastructural changes ciliary process microvessels at the site of aqueous formation in the eyes of diabetic rats and humans. Eyes from the diabetic rats demonstrated cataracts, lower corneal endothelial cell densities, altered aqueous metabolites, and ciliary body ultrastructural changes, including vascular endothelial cell activation, pericyte degeneration, perivascular edema, and basement membrane reduplication. These findings recapitulated diabetic changes in human eyes. These results support the use of this model for studying ocular manifestations of T2DM and support a hypothesis postulating blood-aqueous barrier breakdown and vascular leakage at the ciliary body as a mechanism for diabetic anterior segment pathology.

Inflammation and Neurodegeneration in Glaucoma: Isolated Eye Disease or a Part of a Systemic Disorder? - Serum Proteomic Analysis

Introduction

Glaucoma is the most common optic neuropathy and the leading cause of irreversible blindness worldwide, which affects 3.54% of the population aged 40-80 years. Despite numerous published studies, some aspects of glaucoma pathogenesis, serum biomarkers, and their potential link with other diseases remain unclear. Recent articles have proposed that autoimmune, oxidative stress and inflammation may be involved in the pathogenesis of glaucoma.

Methods

We investigated the serum expression of 92 inflammatory and neurotrophic factors in glaucoma patients. The study group consisted of 26 glaucoma patients and 192 healthy subjects based on digital fundography.

Results

Patients with glaucoma had significantly lower serum expression of IL-2Rβ, TWEAK, CX3CL1, CD6, CD5, LAP TGF-beta1, LIF-R, TRAIL, NT-3, and CCL23 and significantly higher expression of IL-22Rα1.

Conclusion

Our results indicate that patients with glaucoma tend to have lower levels of neuroprotective proteins and higher levels of neuroinflammatory proteins, similar to those observed in psychiatric, neurodegenerative and autoimmune diseases, indicating a potential link between these conditions and glaucoma pathogenesis.

Recommendations for initial diabetic retinopathy screening of diabetic patients using large language model-based artificial intelligence in real-life case scenarios

PURPOSE

To study the role of artificial intelligence (AI) to identify key risk factors for diabetic retinopathy (DR) screening and develop recommendations based on clinician and large language model (LLM) based AI platform opinions for newly detected diabetes mellitus (DM) cases.

METHODS

Five clinicians and three AI applications were given 20 AI-generated hypothetical case scenarios to assess DR screening timing. We calculated inter-rater agreements between clinicians, AI-platforms, and the "majority clinician response" (defined as the maximum number of identical responses provided by the clinicians) and "majority AI-platform" (defined as the maximum number of identical responses among the 3 distinct AI). Scoring was used to identify risk factors of different severity. Three, two, and one points were given to risk factors requiring screening immediately, within a year, and within five years, respectively. After calculating a cumulative screening score, categories were assigned.

RESULTS

Clinicians, AI platforms, and the "majority clinician response" and "majority AI response" had fair inter-rater reliability (k value: 0.21-0.40). Uncontrolled DM and systemic co-morbidities required immediate screening, while family history of DM and a co-existing pregnancy required screening within a year. The absence of these risk factors required screening within 5 years of DM diagnosis. Screening scores in this study were between 0 and 10. Cases with screening scores of 0-2 needed screening within 5 years, 3-5 within 1 year, and 6-12 immediately.

CONCLUSION

Based on the findings of this study, AI could play a critical role in DR screening of newly diagnosed DM patients by developing a novel DR screening score. Future studies would be required to validate the DR screening score before it could be used as a reference in real-life clinical situations.

CLINICAL TRIAL REGISTRATION

Not applicable.

Protective effect of pituitary adenylate cyclase activating polypeptide in diabetic keratopathy

Diabetic keratopathy (DK) is the major complication of the cornea characterizing diabetes-affected patients. This ocular pathology is correlated with the hyperglycemic state leading to delayed corneal wound healing and recurrent corneal ulcers. Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide with widespread distribution throughout the body, and exerting cytoprotective effects in the neural and non-neuronal parts of the eye, including the cornea. The purpose of the present study was to investigate whether changes in PACAP expression can concur for delayed epithelial wound healing in diabetic cornea and whether the protective effect of the peptide could be mediated through the activation of the EGFR signaling pathway, which has been reported to be impaired in DK. Expression and distribution of PACAP, PAC1R, and EGFR were investigated through immunohistochemistry analysis in the cornea of normal and diabetic rats. The role of the peptide on wound healing during DK was evaluated in an in vitro model represented by rabbit corneal epithelial cells grown in high glucose conditions. Western blotting and immunofluorescence analysis were used to examine the ability of PACAP to induce the activation of the EGFR/ERK1/2 signaling pathway. Our results showed that in diabetic cornea the expression of PACAP, PAC1R, and EGFR is drastically reduced. The treatment with PACAP via PAC1R activation enhanced cell viability and corneal epithelium wound healing in cells grown under high glucose conditions. Furthermore, both EGFR and ERK1/2 signaling was induced upon the peptide treatment. Overall, our results showed the trophic efficiency of PACAP for enhancing the corneal epithelium re-epithelialization suggesting that the peptide could be beneficially valuable as a treatment for DK.

Retinal Arteriolar Wall Remodeling in Diabetes Captured With AOSLO

Purpose

Adaptive optics scanning laser ophthalmoscopy (AOSLO) enables the visualization and measurement of the retinal microvasculature structure in humans. We investigated the hypothesis that diabetes mellitus (DM) induces remodeling to the wall structure in small retinal arterioles. These alterations may allow better understanding of vascular remodeling in DM.

Methods

We imaged retinal arterioles in one eye of 48 participants (26 with DM and 22 healthy controls) with an AOSLO. Structural metrics of 274 arteriole segments (203 with DM and 71 healthy controls) ≤ 50 µm in outer diameter (OD) were quantified and we compared differences in wall thickness (WT), wall-to-lumen ratio (WLR), inner diameter (ID), OD, and arteriolar index ratio (AIR) between controls and participants with DM. We also compared the individual AIR (iAIR) in groups of individuals.

Results

The WLR, WT, and AIRs were significantly different in the arteriole segments of DM participants (P < 0.001). The iAIR was significantly deviated in the DM group (P < 0.001) and further division of the participants with DM into groups revealed that there was an effect of the presence of diabetic retinopathy (DR) on the iAIR (P < 0.001).

Conclusions

DM induces remodeling of wall structure in small retinal arterioles and in groups of individuals. The use of AIR allows us to assess remodeling independently of vessel size in the retina and to compute an index for each individual subject.

Translational Relevance

High-resolution retinal imaging allows noninvasive assessment of small retinal vessel remodeling in DM that can improve our understanding of DM and DR in living humans.

Sestrin2 in diabetes and diabetic complications

Diabetes is a global health problem which is accompanied with multi-systemic complications. It is of great significance to elucidate the pathogenesis and to identify novel therapies of diabetes and diabetic complications. Sestrin2, a stress-inducible protein, is primarily involved in cellular responses to various stresses. It plays critical roles in regulating a series of cellular events, such as oxidative stress, mitochondrial function and endoplasmic reticulum stress. Researches investigating the correlations between Sestrin2, diabetes and diabetic complications are increasing in recent years. This review incorporates recent findings, demonstrates the diverse functions and regulating mechanisms of Sestrin2, and discusses the potential roles of Sestrin2 in the pathogenesis of diabetes and diabetic complications, hoping to highlight a promising therapeutic direction.

Analysis of Corneal and Lens Densitometry Changes in Patients With Type 1 Diabetes Mellitus

PURPOSE

By comparing the densitometry findings of patients with type 1 diabetes mellitus (T1DM) and the healthy group, we aimed to understand the possible changes that may occur in the cornea and lens in those with diabetes mellitus (DM).

DESIGN

Prospective, cross-sectional study.

METHODS

A total of 60 eyes of 60 patients with T1DM and 101 eyes of 101 healthy subjects were included in this study. A complete ophthalmologic evaluation was performed in all participants. Scheimpflug tomography was performed to record the corneal and lens densitometry and other tomographic data. Mean glycosylated hemoglobin (HbA1c) and mean DM duration were recorded.

RESULTS

The mean age of the patients with T1DM and patients in the control group was 29.93 ± 8.56 years and 27.27 ± 1 4.96 years, respectively. The mean HbA1c was 8.43 ± 1.92, and the mean DM duration was 14.10 ± 7.77 years. Corneal densitometry (CD) values were significantly higher in the 0- to 2-mm zone in all layers and in the anterior and central 6- to 10-mm zone in the diabetic group (P = .03, P = .018, P = .001, P = .000, P = .004). The mean crystalline lens densitometry was higher in the T1DM group (P = .129). There were positive correlations between DM duration and CD in the anterior 0- to 2-mm (P = .043), central 6- to 10-mm (P = .016), posterior 6- to 10-mm (P = .022), and posterior 10- to 12-mm zone (P = .043).

CONCLUSIONS

CD values were significantly higher in the diabetic group. Diabetes duration and HbA1c values showed correlations with densitometry especially in the 6- to 10-mm corneal zone. Evaluation of the cornea with optical densitometry will be useful in the early diagnosis and follow-up of clinical structural and functional changes in the cornea.

Evaluation of retinal structure and function in prediabetes

Purpose

Alterations in retinal structure and function have been well documented in type 2 diabetes (T2DM). However, few studies have evaluated the eye in prediabetes (preDM), a precursor to T2DM. It is unknown which retinal deficits, if any, occur before T2DM diagnosis. This study evaluates retinal structure via optical coherence tomography (OCT) and retinal function via multifocal electroretinogram (mfERG) N1 and P1 in those with PreDM. The goal is to evaluate associations between structure and function across glucose dysfunction.

Methods

85 subjects (aged 28-69yrs) were tested with VERIS mfERG and Heidelberg Spectralis OCT. Demographic and health information was collected. Subjects were grouped by HbA1c: 33 controls (HbA1c <5.7%), 31 with preDM (HbA1c 5.7-6.4%), and 21 with T2DM (HbA1c >6.4% at the time of testing or diagnosed by physician) and mild or no retinopathy. mfERG N1 and P1 latency and amplitude were measured for the right eye in the foveal hexagon (central 2.4°). Average macular thickness was also measured over the central 3.3°. Groups were compared with ANOVA and corrected t-tests. Models of these associations with diabetes diagnosis (in groups above) were created with backward multivariate regression.

Results

The T2DM group was exceptionally well-controlled with an HbA1c of 7.0% ± 0.68 but also had elevated systolic blood pressure compared to other groups (P<0.01). The age of the control group was younger (P<0.01), so other testing was age controlled. There was a borderline but statistically significant difference in P1 between the control group and both the preDM and T2DM groups after Bonferroni corrections (P<0.03). There was also a difference in N1 latency between the control and other groups (P<0.001). A multivariate model demonstrated a significant relationship between T2DM/PreDM diagnosis and delayed N1 latency, reduced foveal thickness, and age.

Conclusions

Structure and function together can provide an associative model of preDM or T2DM changes for patients. Based on this multivariate model, N1 is strongly associated with preDM and T2DM. N1 findings and decreasing foveal thickness are additive and can together inform ocular health related to preDM. Future longitudinal studies are needed to understand changes in function and structure in preDM and T2DM.

Ocular Delivery of Metformin for Sustained Release and in Vivo Efficacy

Metformin is known to lower inflammation, independent of its anti-diabetic action. Thus, topical metformin can be a therapeutic strategy for managing ocular inflammation associated with diabetes. To achieve this and address the issues of ocular retention and controlled release an in situ gel of metformin was developed. The formulations were prepared using sodium hyaluronate, hypromellose, and gellan gum. The composition was optimized by monitoring gelling time/capacity, viscosity, and mucoadhesion. MF5 was selected as the optimized formulation. It showed both chemical and physiological compatibility. It was found to be sterile and stable. MF5 exhibited sustained release of metformin for 8h that fitted best with zero-order kinetics. Further, the release mode was found to be close to the Korsmeyer-Peppas model. Supported by an ex vivo permeation study, it showed potential for prolonged action. It showed a significant reduction in ocular inflammation that was comparable to that of the standard drug. MF5 shows translational potential as a safe alternative to steroids for managing ocular inflammation.

Cemtirestat, an aldose reductase inhibitor and antioxidant compound, induces ocular defense against oxidative and inflammatory stress in rat models for glycotoxicity

Fructose, endogenously produced as a consequence of activation of the polyol pathway under hyperglycemic conditions, contribute to formation of advanced glycoxidation end products (AGEs) and carbonyl stress. Oxidative stress is increased in diabetes (DM) due to AGEs formation and the utilization of NADPH by aldo-keto reductase, AKR1B1(AR), the first enzyme in polyol pathway. Since inhibition of AR is an attractive approach for the management of diabetic eye diseases, we aimed to compare the effects of a novel AR inhibitor (ARI)/antioxidant (AO) compound cemtirestat on eye tissues with the effects of ARI drug epalrestat and AO agent stobadine in rat model for glycotoxicity. One group of rats was fed high fructose (10% drinking water; 14 weeks), while type-2 DM was induced in the other group of rats with fructose plus streptozotocin (40 mg/kg-bw/day). Diabetic (D) and nondiabetic fructose-fed rats (F) were either untreated or treated with two different doses of cemtirestat (2.5 and 7.5 mg/kg-bw/day), epalrestat (25 and 50 mg/kg-bw/day), or stobadine (25 and 50 mg/kg-bw/day) for 14 weeks. Cemtirestat, epalrestat, and stobadine elaviate the increase in TNF-α, IL-1β, NF-ƙB, and caspase-3 in retina, lens, cornea, and sclera of F and D rats. Both glycotoxicity models resulted in a decrease in GSH to GSSG ratio and a change in glutathione S-transferase activity in eye tissues, but these alterations were improved especially with cemtirestat and stobadine. Lens D-sorbitol of D rats increased more than that of F rats, this increase was only attenuated by cemtirestat and epalrestat. Epalrestat was more effective than cemtirestat and stobadine in inhibiting the increase of vascular endothelial growth factor (VEGF) in the retina of F and D rats. Cemtirestat and stobadine but not epalrestat decreased high level of Nε-(carboxymethyl)lysine in the lens and retina of F and D rats. Cemtirestat is a potential therapeutic in protecting the rat eye against glycotoxicity insults.

Vitamin D and Diabetic Retinopathy

Diabetic retinopathy (DR) is the most common eye disease complication of diabetes, and hypovitaminosis D is mentioned as one of the risk factors. Vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol) are the best-known forms of vitamin D. Calcitriol (1,25-dihydroxycholecalciferol) is the active form of vitamin D, with the sun being one of its main sources. Vitamin D is synthesized in the skin by exposure to sunlight without protective factors, but care must be taken to avoid the development of sunburn. It not only plays an important role in maintaining healthy bones and immune system but has also been highlighted in numerous studies to have an influence on various diseases, including diabetic retinopathy. A large number of people suffer from vitamin D hypovitaminosis worldwide, and diagnosis is made by measuring the concentration of 25-hydroxyvitamin D (25(OH)D) in serum. Its deficiency can cause numerous diseases and, as such, supplementation is necessary. Clinical studies have proven the effectiveness of vitamin D supplementation in the treatment of diabetic retinopathy, but with a doctor's recommendation and supervision due to possible negative side effects.

Risk of cataract and glaucoma among older persons with diabetes in India: a cross-sectional study based on LASI, Wave-1

According to the International Diabetes Federation-2019 estimates, India is home to 77 million diabetic individuals which is projected to grow up to 147.2 million by 2045. Diabetes being a progressive health disorder leads to multiple morbidities and complications including eye diseases and visual impairments. As the burden of diabetes mellitus is increasing, eye problems like cataracts and glaucoma are commonly cited problems among the older adults. In this context, this study aims to provide the public health evidences on diabetes associated burden and risk of developing cataracts and glaucoma among older adults aged 60 and above in India. The analytical sample of this cross-sectional study comprised of 31,464 individuals aged 60 and above. Bivariate cross-tabulation and chi-square test were performed to understand the differential in the prevalence of cataracts and glaucoma by diabetes mellitus including the socio-economic and demographic characteristics of the individuals. Binary logistic regression estimation was executed to estimate the adjusted odds ratio for each of the outcome variables within a multivariate framework. The cataract problem affects more than one-fifth of the older people, while glaucoma affects 2% of them. The prevalence of cataract and glaucoma is 29% among diabetic older adults compared to 22% among non-diabetic persons. In terms of gender, the cataract prevalence is comparatively higher among females (25%) than males (21%). It is important to note that while adjusting for socio-economic and demographic characteristics, the likelihood of cataract (AOR 1.495; p-value < 0.01) and glaucoma (AOR 1.554; p-value < 0.01) is significantly higher among older adults with diabetes than among their counterparts. Medical practitioners should conduct prognosis for diabetic eye problems among patients and raise awareness about the potential risks of developing vision loss, such as cataracts and glaucoma, which are more prevalent among individuals with diabetes.

Ocular images-based artificial intelligence on systemic diseases

PURPOSE

To provide a summary of the research advances on ocular images-based artificial intelligence on systemic diseases.

METHODS

Narrative literature review.

RESULTS

Ocular images-based artificial intelligence has been used in a variety of systemic diseases, including endocrine, cardiovascular, neurological, renal, autoimmune, and hematological diseases, and many others. However, the studies are still at an early stage. The majority of studies have used AI only for diseases diagnosis, and the specific mechanisms linking systemic diseases to ocular images are still unclear. In addition, there are many limitations to the research, such as the number of images, the interpretability of artificial intelligence, rare diseases, and ethical and legal issues.

CONCLUSION

While ocular images-based artificial intelligence is widely used, the relationship between the eye and the whole body should be more clearly elucidated.

Blood pressure control and its associated factors in patients with hypertension and type 2 diabetes

In this retrospective study, the medical records of hypertensive patients with type 2 diabetes attending two major hospitals were reviewed to find the factors associated with poor blood pressure control in patients who have diabetes as a comorbid disease with hypertension. Binary regression analysis was conducted to find the factors independently associated with BP control. A total of 522 participants were included in the study. Most of the participants had uncontrolled hypertension (63.4%) and uncontrolled type 2 diabetes (51.3%). Regression results revealed that having retinopathy (OR=1.468 (95% CI: 1.020-2.113), p&lt;0.05), and not receiving dipeptidyl-peptidase 4 (DPP4) inhibitors were independently associated with uncontrolled BP (OR=0.633 (95%CI 0.423-0.946), p&lt;0.05). Therefore, greater efforts should be exerted to improve BP control in hypertensive patients with type 2 diabetes, particularly in those suffering from retinopathy.

Diabetic patients with and without sodium-glucose cotransporter-2 inhibitors use and cataract risk: real-world observational investigation

PURPOSE

We tried to define the association of type 2 diabetes mellitus (T2DM) patients with and without sodium-glucose cotransporter-2 inhibitors (SGLT2I) use and incident cataract using nationwide data in Taiwan.

METHODS

In a Cox proportional hazards regression model, we estimated the hazard ratios (HR) and 95% confidence intervals (95% CI). We considered risk factors for variables of sex, age, comorbidities and medications that we adjusted in multivariable Cox model.

RESULTS

We identified 20,768 T2DM patients in this study; 10,384 patients in the SGLT2I cohort, and 10,384 controls in the non-SGLT2I cohort. Compared with the T2DM patients without SGLT2I, T2DM patients using SGLT2I had a 2.04-fold increased risk of cataract, after adjustment by sex, age, comorbidities and medications.

CONCLUSION

Increased risk of cataract among diabetic patients who took SGLT2I was found in this study.

Current Approach to the Pathogenesis of Diabetic Cataracts

Cataracts remain the first or second leading cause of blindness in all world regions. In the diabetic population, cataracts not only have a 3–5 times higher incidence than in the healthy population but also affect people at a younger age. In patients with type 1 diabetes, cataracts occur on average 20 years earlier than in the non-diabetic population. In addition, the risk of developing cataracts increases with the duration of diabetes and poor metabolic control. A better understanding of the mechanisms leading to the formation of diabetic cataracts enables more effective treatment and a holistic approach to the patient.

Diabetic retinopathy as a potential risk factor for ptosis: A 13-year nationwide population-based cohort study in Taiwan

Purpose

To determine the risk of ptosis among diabetic retinopathy (DR) patients.

Methods

This is a population-based, retrospective, matched-cohort study where DR patients were recruited from the Taiwan National Health Insurance Research Database (NHIRD) to investigate the risk of developing ptosis. Preexisting co-factors of interest included smoking status and medical comorbidities of hyperlipidemia and hypertension. Statistical analysis was performed using T-test, Cox-proportional hazard ratios adjusted for comorbidities (aHR), Wilcoxon rank sum test, Kaplan-Meier estimators, and log rank tests.

Results

Follow-up data of 9,494 patients with DR and 37,976 matched control cohort (non-DR) from 2000 to 2012 were analyzed. DR patients were found to have significantly increased risk of developing ptosis (adjusted hazard ratio (HR) [95% CI]: 2.76 [1.74-4.38], p < 0.001) when compared to the control cohort. From analysis in different strata, adult age and non-smokers were shown to have higher risk for ptosis development among DR patients. Furthermore, DR patients was also found to have increased risk of developing ptosis when compared to matched controls, regardless of whether they had medical comorbidities of lipid metabolism disorders or hypertension.

Conclusions

In this large-scale study using real-world data, our results showed that DR patients were found to have increased risk of developing ptosis. Female gender, adult age, and non-smokers were also shown to increase the risk of ptosis among DR patients. This has implications towards the care of diabetic patients, complications such as ptosis should be properly screened for when encountering such patients. Before ptosis surgery, the possibility of underlying diabetes or DR should be also scrutinized and treated properly to avoid undesirable postoperative dissension.

Evaluation and comparison of subjective and objective anterior ocular surface damage in patients with type 2 diabetes mellitus and dry eye disease

PURPOSE

To evaluate anterior ocular surface damage in patients with type 2 diabetes mellitus and dry eye disease in comparison to non-diabetic controls based on conjunctival impression cytology, objective scales (Efron, Oxford) and OSDI, to correlate vision-related quality of life with grades of squamous metaplasia in T2DM patients suffering from DED.

METHODS

All participants underwent complete ophthalmologic examination including Shirmer test, TBUT, conjunctival/corneal staining (Oxford scheme), evaluation of conjunctival redness (Efron grading scale), and conjunctival impression cytology (Nelson's scale). The OSDI questionnaire was completed by both groups of patients to assess severity of DED and QoL.

RESULTS

Squamous metaplasia was observed in 94% of the study group and 19.3% of controls (p = 0.0000). Based on the OSDI scores, 73.5% of patients reported mild DED and 26.5% suffered from moderate DED in the study group. The mean OSDI score for the study group with Nelson's grade 2 was 18 ± 3.52 and 20.8 ± 4.68 for Nelson's grade 3, respectively (p = 0.0745). Hence, no significant difference in QoL between grade 2 and grade 3 of squamous metaplasia was observed in patients of the study group.

CONCLUSION

Impression cytology is a reliable minimally invasive tool for an accurate evaluation of the ocular surface damage in patients with DED and type 2 diabetes mellitus. Severe squamous metaplasia (Nelson's grade 3) was observed in 29.4% (10/34) of T2DM patients. In contrast, it was not detected in the control group (p = 0.0032). The absence of goblet cells in T2DM patients nether significantly reduces QoL nor contributes to the subjective DED severity (OSDI) due to complex pathways leading to DED. Thus, diagnosis of DED severity should not be solely based on subjective symptoms in this population.

Ocular complications of diabetes mellitus in a pediatric population and proposals for screening and follow-up programs

Background

Diabetes mellitus (DM) is one of the world's greatest health emergencies of the 21st century. Ocular complications of DM are commonly chronic and progressive, but vision loss can be effectively prevented or delayed with early detection and timely treatment. Therefore, regular comprehensive ophthalmologic examinations are mandatory. Ophthalmic screening and dedicated follow-up for adults with DM are well established, whereas, there is no consensus on optimal recommendations for the pediatric population, reflecting the lack of clarity about the current burden of disease in this age group.

Objectives

To determine the epidemiology of ocular complications of diabetes and to assess optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) macular features in a pediatric population with DM. To review ophthalmological screening and follow-up plans for the diabetic pediatric population.

Design

Observational study.

Methods

Retrospective consecutive cohort study of all 165 diabetic patients (330 eyes) aged 0-18 years, examined between January 2006 and September 2018 at the Pediatric Department of 'S. Maria della Misericordia' Udine Hospital who underwent at least one complete ophthalmologic examination at the Ophthalmology University Clinic at the Udine Hospital. OCT and OCTA data were available for 37 patients (72 eyes, 2 excluded). The associations between ocular complications and selected potential risk factors were evaluated by univariate analyses.

Results

No patient had signs of ocular diabetic complications or any macular morphological or micro-vascular impairment, regardless of any potential risk factor. The prevalence of strabismus and refractive errors in the study group, was found to be similar to non-diabetic pediatric populations.

Conclusion

Screening and follow-up of ocular diabetic complications in children and adolescents could be performed less frequently than in adults with diabetes. There is no need to screen potentially treatable visual disorders in diabetic children earlier or more frequently than in the healthy children thus reducing time spent in hospital and permitting a better tolerance to medical examinations in diabetic pediatric patients. We described the OCT and OCTA patterns in a pediatric population with DM.

A multi-granularity convolutional neural network model with temporal information and attention mechanism for efficient diabetes medical cost prediction

As the cost of diabetes treatment continues to grow, it is critical to accurately predict the medical costs of diabetes. Most medical cost studies based on convolutional neural networks (CNNs) ignore the importance of multi-granularity information of medical concepts and time interval characteristics of patients' multiple visit sequences, which reflect the frequency of patient visits and the severity of the disease. Therefore, this paper proposes a new end-to-end deep neural network structure, MST-CNN, for medical cost prediction. The MST-CNN model improves the representation quality of medical concepts by constructing a multi-granularity embedding model of medical concepts and incorporates a time interval vector to accurately measure the frequency of patient visits and form an accurate representation of medical events. Moreover, the MST-CNN model integrates a channel attention mechanism to adaptively adjust the channel weights to focus on significant medical features. The MST-CNN model systematically addresses the problem of deep learning models for temporal data representation. A case study and three comparative experiments are conducted using data collected from Pingjiang County. Through experiments, the methods used in the proposed model are analyzed, and the super contribution of the model performance is demonstrated.

Adherence to Annual Fundus Exams among Chinese Population with Diagnosed Diabetes

Adherence to annual fundus examinations in the Chinese population with diabetes and its correlates have not been investigated. The present study obtained data for the first nationally representative survey in China, China Health and Retirement Longitudinal Survey (CHARLS), which collected a wide range of data every 2 years, including demographic, socioeconomic, medical and lifestyle-related information. The adherence rates to annual fundus exams across four waves (2011−2018) were assessed. Univariate and multivariable logistic regressions were used to determine factors associated with adherence. The adherence rates to annual fundus examinations of ou study population were 23.6% in 2011, 15.3% in 2013, 17.5% in 2015 and 21.5% in 2018, respectively. Consistent results over four waves showed that non-adherent patients had a relatively lower educational level, insufficient diabetes medication use, fewer non-medication treatments and irregular physical examination compared to those who were adherent to the annual fundus exam (all p values < 0.05). These variables were further identified as factors associated with adherence according to univariate and multivariate logistic regression analyses (all p values < 0.05). The present study provides explicit evidence that the adherence rate to annual fundus examinations among Chinese population with diabetes is worryingly low. Insufficient educational attainment, especially specific diabetes education, has a negative impact on patients’ adherence to clinical guideline for eye health.

Impact of High Glucose on Ocular Surface Glycocalyx Components: Implications for Diabetes-Associated Ocular Surface Damage

Diabetes mellitus causes several detrimental effects on the ocular surface, including compromised barrier function and an increased risk of infections. The glycocalyx plays a vital role in barrier function. The present study was designed to test the effect of a high glucose level on components of glycocalyx. Stratified human corneal and conjunctival epithelial cells were exposed to a high glucose concentration for 24 and 72 h. Changes in Mucin (MUC) 1, 4, 16 expression were quantified using real-time PCR and ELISA. Rose bengal and jacalin staining were used to assess the spatial distribution of MUC16 and O-glycosylation. Changes in the gene expression of five glycosyltransferases and forty-two proteins involved in cell proliferation and the cell cycle were also quantified using PCR and a gene array. High glucose exposure did not affect the level or spatial distribution of membrane-tethered MUC 1, 4, and 16 either in the corneal or conjunctival epithelial cells. No change in gene expression in glycosyltransferases was observed, but a decrease in the gene expression of proteins involved in cell proliferation and the cell cycle was observed. A high-glucose-mediated decrease in gene expression of proteins involved in cellular proliferation of corneal and conjunctival epithelial cells may be one of the mechanisms underlying a diabetes-associated decrease in ocular surface's glycocalyx.

Diabetic Patients With Rosacea Increase the Risks of Diabetic Macular Edema, Dry Eye Disease, Glaucoma, and Cataract

PURPOSE

Inflammation plays a role in diabetic eye diseases, but the association between rosacea and eye diseases in patients with diabetes remains unknown.

DESIGN

This retrospective cohort study used claims data from the National Health Insurance Research Database in Taiwan to investigate the association between rosacea and eye diseases in patients with diabetes.

MATERIALS AND METHODS

Taiwanese patients diagnosed as having diabetes mellitus between January 1, 1997, and December 31, 2013, and using any hypoglycemic agents were included and divided into rosacea and nonrosacea groups. After applying 1:20 sex and age matching and exclusion criteria, 1:4 propensity score matching (PSM) was conducted to balance the covariate distribution between the groups. The risk of time-to-event outcome between rosacea and nonrosacea groups in the PSM cohort was compared using the Fine and Gray subdistribution hazard model.

RESULTS

A total of 4096 patients with rosacea and 16,384 patients without rosacea were included in the analysis. During a mean follow-up period of 5 years, diabetic patients with rosacea had significantly higher risks of diabetic macular edema [subdistribution hazard ratio (SHR): 1.31, 95% confidence interval (CI): 1.05-1.63], glaucoma with medical treatment (SHR: 1.11, 95% CI: 1.01-1.21), dry eye disease (SHR: 1.55, 95% CI: 1.38-1.75), and cataract surgery (SHR: 1.13, 95% CI: 1.02-1.25) compared with diabetic patients without rosacea. A cumulative incidence analysis performed up to 14 years after the index date revealed that the risks of developing ocular diseases consistently increased over time. No significant differences in diabetic retinopathy, age-related macular degeneration, retinal vascular occlusion, ischemic optic neuropathy, optic neuritis, uveitis, or retinal detachment were identified according to rosacea diagnosis. However, we observed significant associations between rosacea and psoriasis, irritable bowel syndrome, anxiety, and major depressive disorder among patients with diabetes.

CONCLUSIONS

Rosacea is associated with diabetic macular edema, glaucoma, dry eye disease, and cataract development in diabetic patients, as well as increased risks of psoriasis, irritable bowel syndrome, anxiety, and depression in diabetic patients.

Monocarboxylate Transporters: Role and Regulation in Corneal Diabetes

Diabetes mellitus (DM) is a group of metabolic diseases that is known to cause structural and functional ocular complications. In the human cornea, DM-related complications affect the epithelium, stroma, and nerves. Monocarboxylate transporters (MCTs) are a family of proton-linked plasma membrane transporters that carry monocarboxylates across plasma membranes. In the context of corneal health and disease, their role, presence, and function are largely undetermined and solely focused on the most common MCT isoforms, 1 through 4. In this study, we investigated the regulation of MCT1, 2, 4, 5, 8, and 10, in corneal DM, using established 3D self-assembled extracellular matrix (ECM) in vitro models. Primary stromal corneal fibroblasts were isolated from healthy (HCFs), type I (T1DMs), and type II (T2DMs) DM donors. Monoculture 3D constructs were created by stimulating stromal cells on transwells with stable vitamin C for two or four weeks. Coculture 3D constructs were created by adding SH-SY5Y neurons at two different densities, 12 k and 500 k, on top of the monocultures. Our data showed significant upregulation of MCT1 at 4 weeks for HCF, T1DM, and T2DM monocultures, as well as the 500 k nerve cocultures. MCT8 was significantly upregulated in HCF and T1DM monocultures and all of the 500 k nerve cocultures. Further, MCT10 was only expressed at 4 weeks for all cocultures and was limited to HCFs and T1DMs in monocultures. Immunofluorescence analysis showed cytoplasmic MCT expression for all cell types and significant downregulation of both MCT2 and MCT4 in HCFs, when compared to T1DMs and T2DMs. Herein, we reveal the existence and modulation of MCTs in the human diabetic cornea in vitro. Changes appeared dependent on neuronal density, suggesting that MCTs are very likely critical to the neuronal defects observed in diabetic keratopathy/neuropathy. Further studies are warranted in order to fully delineate the role of MCTs in corneal diabetes.

Ischemia Modified Albumin (IMA) as a New Biomarker in the Ophthalmology Field: A Brief Literature Review

Purpose:

This study aimed to review the potential role of ischemia-modified albumin as a biomarker for diagnostic modalities in the ophthalmology field.

Methods:

Articles were reviewed without a specific date. A manual search was also performed by reviewing reference lists of meta-analyses and systematic reviews. All articles were reviewed, and a total of 18 articles were selected by the authors.

Results:

Oxidative stress increases structural and functional damage to proteins in many ocular diseases. The human serum albumin is a major circulating protein with antioxidative and anti-inflammatory properties. Oxidative stress has been shown to be an important part of etiology and pathogenesis in ocular diseases related to ischemia. Biomarkers that are specific to oxidative stress and ischemia-related ocular pathogenesis are needed to provide an extensive understanding regarding diagnosis, monitoring progression, and new potential target treatment. Ischemia-modified albumin (IMA) as a new promising biomarker might be useful in the early detection and treatment of ocular diseases with ischemic pathogenesis.

Conclusion:

IMA plays an important role in the progression of ophthalmology diseases, such as diabetic retinopathy, hypertensive retinopathy, cataract progression, seasonal allergies, and glaucoma. Further studies are needed to elaborate these results as a consideration in new testing modalities in clinical practice as well as a new target therapy research.

Assessment of tear inflammatory cytokines concentration in patients with diabetes with varying severity of involvement

Diabetic retinopathy (DR), as one of the most important causes of blindness in Western societies, is a common micro-vasculopathy associated with diabetes. There is growing evidence of the role of inflammation in its development. This study was designed to measure cytokines in patients with diabetes with different stages of retinopathy .In this study, tear concentrations of three types of cytokines with different angiogenic properties including IL-1RA, IL-8, and TNF-α were measured in patients with diabetes without retinopathy, with non-proliferative retinopathy, with proliferative retinopathy, and in a healthy control group. The results showed that concentrations of TNF-α and IL-8 were higher in the tear sample of diabetics than in the control group and the concentrations of these cytokines were higher in patients with more advanced stages of diabetes, while the tear level of IL-1RA was significantly lower in diabetics. Based on these findings, it can be concluded that diabetes and its progression of severity affects the tear levels of IL-1RA, IL-8, and TNF-α inflammatory cytokines.

High Fasting Blood Sugar and Increased Waist Circumference as Risk Factors for Diabetic Retinopathy in Type 2 Diabetes Patients Older than 45 Years

Introduction

Diabetes mellitus (DM) has a long-term impact on retinal micro-blood vessels, culminating in the progression of diabetic retinopathy (DR); however; screening for DR is not widely used due to a lack of accessibility and economic constraints, especially in resource-limited settings. Thus, a longitudinal marker that is associated with the development of DR is required. This study sought to assess the association of DR with fasting blood sugar (FBS) levels and waist circumference.

Methodology

A cross-sectional study was conducted in a tertiary care hospital for one year. All individuals diagnosed with Type 2 DM (T2DM) and ≥45 years of age were included in the study. Individuals with fasting blood glucose levels of <126 mg/dl and <3 years of diagnosis with T2DM were excluded from the study. Individuals having one or more retinal microaneurysms or retinal blot hemorrhages, with or without any additional abnormalities, were diagnosed with DR. The results were analyzed using SPSS version 21 (IBM Corp., Armonk, NY).

Results

The prevalence of diabetic retinopathy among the study participants was 67.6 %. There was a significant association between increasing waist circumference (p = 0.009) and High FBS levels (p = 0.032) with the presence of DR.

Conclusion

Approximately two-thirds of the patients with T2DM aged >45 years and above have diabetic retinopathy. High FBS and waist circumference were associated with DR.