Risk Factors for Giant Retinal Tears

Purpose: To evaluate the risk factors associated with giant retinal tears. Methods: This retrospective study was performed on medical records of 150 patients who had undergone retinal detachment surgery. Age, sex, history of trauma, lens status (phakic, pseudophakic, or aphakic), and high myopia were evaluated in association with giant retinal tears. Results: Of 150 patients with retinal detachments, 99 subjects (66%) were older than 30 years while 51 (34%) were 30 years of age or younger. Overall, 26 (17.3%) patients had giant retinal tears. Controlling for all variables, only age had a significant correlation with giant retinal tears. Each year of advancing age was associated with a 6% decrease in the incidence of giant retinal tears. Conclusion: Young age is a significant risk factor for development of giant retinal tears

Serum Levels of Vitamin D in Diabetic Patients With and Without Retinopathy

Purpose: To evaluate the levels of vitamin D in the serum of diabetic patients with and without diabetic retinopathy (DR). Methods: Thirty patients with DR and thirty diabetic patients without retinopathy were included in this cross-sectional study. Based on ophthalmic examination, patients with DR were categorized into having non-proliferative retinopathy (NPDR) and proliferative retinopathy (PDR). Patients were tested for fasting blood sugar (FBS), hemoglobin A1C (HbA1C), 25-hydroxy vitamin D (25 (OH) D), and creatinine levels in the serum, and for urine protein. Vitamin D deficiency was defined as a serum 25 (OH) D level < 20 ng/mL. Results: We found that all diabetic patients had mild vitamin D deficiency (serum 25 (OH) D level = 10–20 ng/mL). The mean serum 25 (OH) D concentration in patients with DR was lower than in those without DR (12.10 ± 14.62 ng/mL vs 15.61 ± 9.40 ng/mL, respectively, P = 0.012). Trace or more proteinuria was frequently present in patients with DR than in those without DR (56% in DR vs 30% in non-DR; P = 0.037). There were no significant differences in the FBS, HbA1C, and serum creatinine levels between patients with or without retinopathy. Conclusion: The present study demonstrated that patients with DR had lower levels of serum vitamin D compared with those without retinopathy

The Association of Serum Leptin Level and Anthropometric Measures With the Severity of Diabetic Retinopathy in Type 2 Diabetes Mellitus

This study was performed to determine the association amongst serum leptin level and anthropometric measures with the severity of Diabetic Retinopathy (DR) in subjects with type 2 Diabetes Mellitus (DM). This case-controlled study was conducted within a one-year period, during year 2016, at outpatient retina ophthalmology clinics of Shiraz, southern Iran. Eighty-three patients with type 2 DM, referring for ophthalmoscopy evaluation, were included. Anthropometric measures, serum leptin level, and baseline laboratory assessment was performed for all subjects. Patients were categorized as group 1, consisting of patients with severe Non-Proliferative Diabetic Retinopathy (severe NPDR) and Proliferative Diabetic Retinopathy (PDR) (n = 44), and group 2, consisting of patients without Diabetic Retinopathy (no DR) or mild/moderate NPDR (n = 39). The serum leptin level and anthropometric measures were compared between the two study groups. The correlation between these variables was also assessed. The mean age of the participants was 59.3 ± 6.9 years old. The two study groups were comparable regarding baseline characteristics. Cases of group 1 had significantly higher Erythrocyte Sedimentation Rate (ESR) (P = 0.049) and Systolic Blood Pressure (P = 0.025) when compared with those of group 2. The serum level of leptin was found to be significantly higher in cases of group 1 when compared to those of group 2 (P = 0.003). However, anthropometric measures, including Body Mass Index (BMI) (P = 0.167), Body Adiposity Index (BAI) (P = 0.061), and Waist to Hip Ratio (WHR) (P = 0.220) were comparable between the two study groups. Serum leptin level was positively correlated with BMI (r = 0.819; P < 0.001) and BAI (r = 0.630; P < 0.001) in group 1. Increased serum levels of leptin were associated with advanced stages of DR in subjects with type 2 DM. Serum leptin level might be a better indicator of the effects of obesity on DR, compared to anthropometric measures (BAI or BMI)

An Open-source Image Analysis Toolbox for Quantitative Retinal Optical Coherence Tomography Angiography

Background: Qualitative and quantitative assessment of retinal perfusion using optical coherence tomography angiography (OCTA) has shown to be effective in the treatment and management of various retinal and optic nerve diseases. However, manual analyses of OCTA images to calculate metrics related to Foveal Avascular Zone (FAZ) morphology, and retinal vascular density and morphology are costly, time-consuming, subject to human error, and are exposed to both inter and intra operator variability.Objective: This study aimed to develop an open-source software framework for quantitative OCTA (QOCTA). Particularly, for analyzing OCTA images and measuring several indices describing microvascular morphology, vessel morphology, and FAZ morphology.Material and Methods: In this analytical study, we developed a toolbox or QOCTA using image processing algorithms provided in MATLAB. The software automatically determines FAZ and measures several parameters related to both size and shape of FAZ including area, perimeter, Feret’s diameter circularity, axial ratio, roundness, and solidity. The microvascular structure is derived from the processed image to estimate the vessel density (VD). To assess the reliability of the software, three independent operators measured the mentioned parameters for the eyes of 21 subjects. The consistency of the values was assessed using the intraclass correlation coefficient (ICC) index.Results: Excellent consistency was observed between the measurements completed for the superficial layer, ICC >0.9. For the deep layer, good reliability in the measurements was achieved, ICC >0.7. Conclusion: The developed software is reliable; hence, it can facilitate quantitative OCTA, further statistical comparison in cohort OCTA studies, and can assist with obtaining deeper insights into retinal variations in various populations

Mesenchymal Stem Cells and COVID-19: Cure, Prevention, and Vaccination

COVID-19 disease has been a global health problem since late 2019. There are many concerns about the rapid spread of this disease, and yet, there is no approved treatment for COVID-19. Several biological interventions have been under study recently to investigate efficient treatment for this viral disease. Besides, many efforts have been made to find a safe way to prevent and vaccinate people against COVID-19 disease. In severe cases, patients suffer from acute respiratory distress syndrome usually associated with an increased level of inflammatory cytokines, called a cytokine storm. It seems that reequilibrating the hyperinflammatory response of the host immune system and regeneration of damaged cells could be the main way to manage the disease. Mesenchymal stem cells (MSCs) have been recently under investigation in this regard, and the achieved clinical outcomes show promising evidence for stem cell-based therapy of COVID-19. MSCs are known for their potential for immunomodulation, defense against virus infection, and tissue regeneration. MSCs are a newly emerged platform for designing vaccines and show promising evidence in this area. In the present study, we provided a thorough research study on the most recent clinical studies based on stem cells in the treatment of COVID-19 while introducing stem cell exclusivities for use as an immune disorder or lung cell therapy and its potential application for protection and vaccination against COVID-19

Evaluation of serum interferons in patients with age-related macular degeneration

Background: Environmental, genetic, and immunological factors may play a role in the pathogenesis of age-related macular degeneration (AMD). In an attempt to better understand the pathogenesis of AMD, in this study, we evaluated the serum interferon (IFN) levels in patients with AMD and compared it with persons without AMD. Materials and Methods: In this case–control study, 42 patients with AMD and 42 healthy individuals (without AMD) were enrolled as the case and control groups, respectively. The two groups were matched regarding their age and sex. We classified the case group as dry-type and wet-type AMD. Blood samples were obtained and the serum was collected and frozen at −20°C. Alpha-, beta-, and gamma-IFN levels were measured using the sandwich ELISA method and compared between and within the groups. Results: The mean beta IFN levels in both case and control groups were 46.88 ± 27.25 pg/ml and 34.90 ± 18.81 pg/ml (P = 0.021), respectively. Regarding gamma and alpha IFN, the serum levels were not detectable in most of the patients and no significant difference was detected between the case and control groups. Conclusion: We found that serum beta IFN levels are higher in patients with AMD. This finding may have diagnostic, therapeutic, and prognostic value in AMD patients and can be a beginning for further evaluation

Medical Follow-ups of Patients with Diabetic Retinopathy

Background: Diabetic retinopathy is the most common cause of blindness in 25-65 years old age population. Early diagnosis and treatment of diabetes can delay diabetic retinopathy. The aim of this study is to evaluate medical follow up of patients with diabetic retinopathy. Methods: In a descriptive cross-sectional design, patients with diabetic retinopathy, who had been referred for operation or laser therapy, were interviewed by an ophthalmologist and questionnaires were completed. Results Of 100 patients with mean age of 53 years, 65% were female and 35% were male. 50% of patients were illiterate. 24% of patients had regular ophthalmologist follow up and 75% of patients had no regular follow up. Causes of poor follow up were low awareness (42%), economical factors (12%), lack of family support (8%) and ophthalmologist unavailability (6%). Conclusion: Augmenting our information about the follow up of diabetic patients and probable problems in this trend can help the health organizations in order to design more effective control programs for them. It seems that a regional follow up protocol for diabetes is needed to check the trend of quality of care of diabetes in Iran

Diabetic Retinopathy and BDNF: A Review on Its Molecular Basis and Clinical Applications

Impairment of neuroprotection and vasculopathy are the main reasons for the progression of diabetic retinopathy. In this review, we decided to illustrate the molecular and clinical aspects of diabetic retinal neuro-vasculopathy. We searched the Web of Science, PubMed, and Scopus databases with these keywords: “brain-derived neurotrophic factor” and “vascular endothelial growth factor” and/or “diabetic retinopathy.” The most relevant in vitro and clinical trial studies were then extracted for final interpretation. Brain-derived neurotrophic factor and the vascular endothelial growth factor have pivotal roles in the pathogenesis of diabetic retinopathy. They have neuroprotective effects on the retina. However, there are controversial results on the relation between these two factors. Reviewing available articles, we have concluded that various concentrations of these molecules at different stages of retinopathy may exert different effects. Optimal doses of the brain-derived neurotrophic factor at the early stages of retinopathy may have a neuroprotective effect. In contrast, higher concentrations of brain-derived neurotrophic factor might induce inflammatory responses. Damage to the retinal cells due to metabolic alterations associated with diabetes and its consequence vasculopathy may also lead to changes in the ocular microenvironment and cytokines. Changes in cytokines result in the modification of neural cell receptors and the overproduction of vascular endothelial growth factor. It seems that controlling the optimal levels of neuroprotective molecules in the retinal tissue is the main step to halter diabetic retinopathy

Serum Levels of Vitamin D in Diabetic Patients with and Without Retinopathy

Purpose: To evaluate the levels of vitamin D in the serum of diabetic patients with and without diabetic retinopathy (DR). Methods: Thirty patients with DR and thirty diabetic patients without retinopathy were included in this cross-sectional study. Based on ophthalmic examination, patients with DR were categorized into having non-proliferative retinopathy (NPDR) and proliferative retinopathy (PDR). Patients were tested for Fasting blood sugar (FBS), hemoglobin A1C (HbA1C), 25-hydroxy vitamin D (25 (OH) D), and creatinine levels in the serum, and for urine protein. Vitamin D deficiency was defined as a serum 25 (OH) D level < 20 ng/mL. Results: We found that all diabetic patients had mild vitamin D deficiency (serum 25 (OH) D level = 10–20 ng/mL). The mean serum 25 (OH) D concentration in patients with DR was lower than in those without DR (12.10 ± 14.62 ng/mL vs 15.61 ± 9.40 ng/mL, respectively, P = 0.012). Trace or more proteinuria was frequently present in patients with DR than in those without DR (56% in DR vs 30% in non-DR; P = 0.037). There were no significant differences in the FBS, HbA1C, and serum creatinine levels between patients with or without retinopathy. Conclusion: The present study demonstrated that patients with DR had lower levels of serum vitamin D compared with those without retinopathy