Retinal Examination Research Articles

Peripheral Retinal Abnormalities and Retinal Detachment in Pathologic Myopia

Pathological myopia is associated with changes in various structures of the eye, primarily the retina. Peripheral retinal degenerations are common findings in patients, and serious vision loss can develop as a result of retinal detachment, whether or not it occurs on a background of degeneration. The dynamic interaction between the retina and the vitreous plays an important role in the formation of degenerations and the development of retinal detachment with tears. A careful retinal examination that evaluates all quadrants during patient check-ups can prevent permanent vision loss by conducting risk analyses for observed degenerations and holes and taking appropriate precautions.

Affordable ultra-widefield smartphone PedCam for comprehensive pediatric retinal examination

Widefield fundus photography is critical for the detection, documentation, and management of pediatric eye diseases. Existing clinical pediatric fundus cameras offer a limited field of view (FOV) and suboptimal image contrast, hindering comprehensive peripheral retina examination. Additionally, the high cost and lack of portability of commercial devices restrict their use in resource-limited settings. We introduce a cost-effective smartphone-based pediatric camera (PedCam) that provides a 180° eye angle (126° visual angle) snapshot FOV. Utilizing trans-pars planar illumination, the device enables nonmydriatic imaging by allocating the pupil exclusively for imaging, eliminating the need for pharmacological pupillary dilation. By adjusting the optical axis of the PedCam relative to the ocular axis, the effective FOV can be expanded up to 240° eye angle (180° visual angle), enabling complete retinal evaluation. This innovative smartphone PedCam represents a significant advancement in affordable telemedicine for the screening, monitoring, and management of retinopathy of prematurity and other pediatric eye conditions.

Invasive Candidiasis in Pediatric Hematologic Malignancy: Increased Risk of Dissemination With Candida tropicalis.

Candida species are the most common cause of invasive fungal disease, and children with hematologic malignancy are at increased risk. Non-albicans Candida (NAC) now account for more than half of all invasive candidiasis (IC) and carry a worse prognosis. We aimed to compare the epidemiology, risk factors, organ dissemination, biomarkers and outcomes in IC based on the species implicated and evaluate trends in antifungal resistance over time. Patients 0-18 years of age with hematologic malignancy and IC at 2 centers were included. Fifty-three patients from 2011 to 2022 were identified. Information related to demographics, host and risk factors, Candida species and antifungal susceptibilities, treatment and outcomes was collected via retrospective chart review. Data were analyzed at the species level. The incidence rate of IC was 29 per 1000 patients with leukemia and lymphoma. The median time to infection from diagnosis of malignancy was 38 days. Candida tropicalis (n = 17; 30%) was the most identified species followed by Candida albicans (n = 14; 25%). Patients with C. tropicalis infection were more likely to have dissemination to the eyes (P = 0.035), spleen (P = 0.001) and skin (P = 0.003) than patients with C. albicans or other NAC. Of the 34 patients who underwent dilated retinal examination, 24% (n = 8) had evidence of intraocular candidiasis. Seven of the 8 patients with intraocular disease had prolonged candidemia (3 or more days; P = 0.003). The 12-week crude mortality rate was 16.9%. NAC, specifically C. tropicalis, accounted for most of the IC in children with hematological malignancies. Screening for intraocular candidiasis continues to play an important role in patients with IC, and future studies are needed to determine if screening can be limited to patients with select risk factors.

Retinopathy of prematurity screening: can the examination time be reduced?

ABSTRACT Clinical relevance Retinopathy of prematurity (ROP) is a significant cause of childhood blindness. Screening examinations that maintain accuracy, while improving the experience for families, could increase adherence to follow-up and decrease workload. Background Traditional ROP screening examinations are known to be uncomfortable for babies and stressful for parents. A new strategy is proposed and tested for the accuracy of the outcome and the time taken. Methods In this new screening strategy, the examiner performs a complete retinal examination on the first visit. If the area and stage of the nasal and temporal retinal regions are similar or the stage of the temporal half is worse, only the posterior pole and temporal half of the retina are evaluated at subsequent visits. A retrospective patient file review was conducted to compare the new proposal with accepted methods. ROP examination time was compared prospectively. Results The data of 57 consecutive patients treated for ROP were evaluated. The ROP zone was the same in the nasal and temporal retina in all eyes at the first and last visit before treatment. Only two eyes had worse ROP stage in the nasal half at presentation but both halves developed the same degree of stage during follow-up. None of the treatment decisions were based only on the nasal region of the retina. Examination time was evaluated in 40 eyes of 20 infants. The average total time required for an examination with the accepted method was 241.3 ± 112.5 seconds. However, with the proposed strategy, the examination time was significantly reduced to 172.3 ± 69.2 seconds (p < 0.001). Conclusions This screening strategy shortens examination time, which may help reduce pain and related adverse events.

Comparison of Retinal Thickness betweenDiabetic Patients without Diabetic Retinopathy and Non-Diabetic Controls Using SD-OCT

Purpose: To determine retinal thickness in diabetic patients without diabetic retinopathy and non-diabetic controls using Spectral Domain Optical Coherence Tomography (SD-OCT). Study Design: Cross-sectional observational study. Place and Duration of Study: Diabetic Eye Clinic and General Eye OPD of Al-Ibrahim Eye Hospital, Karachi from July 2018 to August 2018. Methods: Patients with type 2 diabetes and non-diabetic healthy control eyes of either genderand age between 20 and 60 years were recruited. Patients with any other systemic and ocular disease affecting retinal thickness were excluded. After initial examination and informed written consent, patients were referred to ocular investigation department for detailed retinal examination and SD-OCT for measuring central retinal thickness. Data were analyzed for continuous and categorical variable using SPSS. Results: Average Central Retinal thickness was 297±21 and 315±13µmand Central Foveal Thickness was 246±16 and 249±19µmin diabetic and non-Diabetic patients respectively. Quadrant-wise evaluation revealed retinal thickness as follows; nasal 310 and 324µm), temporal (291and 304µm), superior (297and 316µm) and inferior (292and 314µm) in diabetics and non-diabetics respectively. Retinal thickness was greater at nasal and lesser at temporal regions. Conclusion: Diabetic patients without DR had thinner central retinal thickness compared to non-diabetic controls, as measured by Spectral Domain Optical Coherence Tomography (SD-OCT). Specifically, the average central retinal thickness and central foveal thickness were slightly reduced in diabetic patients. Quadrant-wise analysis revealed that the retinal thickness was consistently greater in the nasal region and lesser in the temporal region in both diabetic and non-diabetic patients.

Applications of optical coherence tomography angiography in glaucoma: current status and future directions.

Glaucoma is a leading cause of irreversible blindness worldwide, with its pathophysiology remaining inadequately understood. Among the various proposed theories, the vascular theory, suggesting a crucial role of retinal vasculature deterioration in glaucoma onset and progression, has gained significant attention. Traditional imaging techniques, such as fundus fluorescein angiography, are limited by their invasive nature, time consumption, and qualitative output, which restrict their efficacy in detailed retinal vessel examination. Optical coherence tomography angiography (OCTA) emerges as a revolutionary imaging modality, offering non-invasive, detailed visualization of the retinal and optic nerve head microvasculature, thereby marking a significant advancement in glaucoma diagnostics and management. Since its introduction, OCTA has been extensively utilized for retinal vasculature imaging, underscoring its potential to enhance our understanding of glaucoma's pathophysiology, improving diagnosis, and monitoring disease progression. This review aims to summarize the current knowledge regarding the role of OCTA in glaucoma, particularly its potential applications in diagnosing, monitoring, and understanding the pathophysiology of the disease. Parameters pertinent to glaucoma will be elucidated to illustrate the utility of OCTA as a tool to guide glaucoma management.

SUCCESSFUL TREATMENT OF VON HIPPEL-LINDAU DISEASE-ASSOCIATED RETINAL CAPILLARY HEMANGIOBLASTOMA WITH BELZUTIFAN IN A PEDIATRIC PATIENT.

The authors describe a case of a retinal capillary hemangioblastoma (RCH) in a pediatric patient with von Hippel-Lindau (VHL) syndrome that was successfully treated with systemic belzutifan. The clinical course was documented with serial fundus examinations and multimodal imaging, including Optos widefield fundus photography and optical coherence tomography. A literature review was conducted to look for similar cases and/or discussion. A left RCH was noted on a standard VHL surveillance retinal examination of a then 15-year-old male patient with VHL syndrome. Over the course of 17 months, this RCH was treated with focal laser therapy, photodynamic therapy, cryotherapy, bevacizumab injection, and endolaser ablation. Complications of these treatments included subretinal fluid and vitreomacular traction necessitating laser retinopexy, scleral buckle, and pars plana vitrectomy with membrane stripping. After a 6-month interval from the last local therapy (endolaser treatment), there was minimal regression of the lesion, and many concerning features persisted. At 22 months from presentation, the patient started belzutifan 120 mg PO daily with subsequent regression in size and less perfusion to the hemangioblastoma within 4 months. The patient is tolerating the systemic belzutifan with only the expected normocytic anemia and has not required transfusion therapy after 12 months of treatment. von Hippel-Lindau disease is a rare and serious condition associated with multiple types of benign and malignant tumors. Belzutifan is tolerated in the adolescent population and can provide a systemic treatment alternative for VHL-associated RCH.

Pre-term Familial Exudative Vitreoretinopathy: A Novel Nonsense LRP5 Mutation.

This case report details the diagnosis and management of a pre-term infant with aggressive bilateral retinal pathology. A 4-week-old preterm baby girl, born at 28 weeks and 6 days to consanguineous parents, was referred for suspected aggressive posterior retinopathy of prematurity (ROP). She had a family history of bilateral retinal detachments and intellectual disability in an older sister. Clinical assessment included retinal examination, fluorescein angiography, optical coherence tomography, dual-energy X-ray absorptiometry (DEXA), and genetic testing. The genetic testing involved sequence analysis and copy number variation analysis of 25 genes related to vitreoretinopathy. Retinal examination and fluorescein angiography revealed extensive non-perfusion and telangiectatic vessels in both eyes, and a macula-involving tractional retinal detachment in the left eye. Despite treatment with intravitreal bevacizumab and laser photocoagulation, they progressed to total retinal detachment and no light perception in both eyes. Genetic testing revealed a pathogenic homozygous nonsense mutation in the LRP5 gene (c.3259C>T, p.(Gln1087*)), a mutation not previously reported in association with familial exudative vitreoretinopathy (FEVR). At 10 months of age, DEXA demonstrated normal bone density, diverging from the typical presentation of osteoporosis pseudoglioma syndrome associated with LRP5 mutations. This case describes a novel mutation in a complex retinal disease and underscores the necessity of considering pre-term FEVR in the differential diagnosis of atypical or aggressive ROP in preterm infants. The overlap in clinical features between ROP and FEVR highlights the complexity of diagnosis and management and the importance of genetic testing in preterm infants with retinal vascular abnormalities.

Exposure to per- and polyfluoroalkyl substances and age-related macular degeneration in U.S. middle-aged and older adults

Despite various health effects of per- and polyfluoroalkyl substances (PFAS) exposure, the association between PFAS exposure and age-related macular degeneration (AMD) has not been investigated. We aimed to assess associations of PFAS exposure with AMD, using data from 1722 U.S. adults aged 40 years or more participating in the National Health and Nutrition Examination Survey 2005–2008 with complete data on PFAS measurement, AMD diagnosis, and covariates. Serum concentrations of PFAS, including perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorohexane sulfonic acid (PFHxS), and perfluorooctane sulfonic acid (PFOS), were measured. An overall PFAS burden score was calculated using item response theory scoring. Individual PFAS concentration and overall PFAS burden score were categorized into low (reference), medium, and high groups. Diagnosis of AMD was based on retinal image examination. Any AMD was defined as the presence of early or late AMD. Survey-weighted logistic regression adjusted for potential confounders was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for presence of AMD according to PFAS exposure. Overall, 132 (6.5%) individuals were diagnosed as any AMD, including 115 (5.7%) individuals with early AMD. A significant dose-response association was observed between serum PFOS concentration and any AMD (p-trend = 0.03), with a significant OR of 1.99 (95% CI: 1.05, 3.79) for the high group compared to the reference. Overall PFAS burden showed a non-monotonic association with any AMD, with a significant OR of 2.18 (95% CI: 1.18, 4.04) for the medium. Inverted U-shaped associations were observed by restricted cubic spline analyses. Also, early AMD showed similar patterns in PFOS and overall PFAS burden and additionally an inverted U-shape association in PFNA. Our findings suggest that exposure to PFAS estimated by serum PFOS and PFNA as well as overall PFAS burden might be a risk factor for AMD in middle-aged and older population.

A novel compound heterozygous variant of MYO7A in Usher syndrome type 1

Usher syndrome (USH) is a recessive genetic disorder manifested by congenital sensorineural hearing loss and progressive retinitis pigmentosa, which leads to audiovisual impairment. We report a patient with Usher syndrome type 1 with new compound heterozygous MYO7A variants. A total of four members from the USH family were included. Medical history and retinal examinations were taken and genomic DNA from peripheral blood was extracted in the proband and other members. 381 retinal disease-associated genes were screened using targeted sequence capture array technology and Sanger sequencing was used to confirm the screening results. Scanning laser ophthalmoscope showed bone spicule pigmentary deposits in the mid-peripheral retina and whitish and thin retinal blood vessels especially in the arterioles. Optical coherence tomography showed that the centrality of the macular ellipsoid band disappeared in both eyes, and only remained near the fovea. Visual field examination showed a progressive loss of the visual field in a concentric pattern in both eyes. The electroretinography showed a significant decrease in the amplitudes of a- and b-waves in the scotopic and photopic condition. DNA sequencing identified the compound heterozygous variants including c.1003+1G > A: p. (?) and c.5957_5958del: p.G1987Lfs*50 of MYO7A, with the latter being novel. In this study, we found a novel compound heterozygous variant in MYO7A, which enriched the mutation spectrum and expanded our understanding of the heterogeneity of phenotype and genotype of Usher syndrome type 1.

Virtual Reality With Eye Tracking for Pediatric Ophthalmology: A Systematic Review.

Virtual reality presents an efficient and engaging approach to ophthalmological diagnosis and treatment in children. This systematic review investigates the current state of eye tracking technology integrated into virtual reality for the spectrum of pediatric ophthalmology. The search encompassed the MEDLINE database via PubMed, without imposing any time restrictions. A total of 20 relevant studies that met our inclusion criteria were incorporated and categorized into the following domains: diagnosis, examination, treatment, and rehabilitation use of virtual reality devices within the realm of pediatric ophthalmology. Strabismus examinations and postoperative monitoring, inherited retinal degeneration examination and visual function testing, therapy of amblyopia, glaucoma visual field testing, cerebral visual impairment rehabilitation, and neuro-ophthalmic disease examination were included in the final analysis. Pediatric ophthalmology offers a promising landscape for the integration of eye tracking technology within virtual reality, with accelerated, quantifiable, and objective examination and diagnosis, and precise, real-time measurements that are crucial in children. Virtual reality is an engaging experience, easily applied in a pediatric setting and facilitating compliance during examination and adherence to therapy. Although our systematic review provides insights into the current state of research, it is anticipated that further exploration is required for the widespread utilization of eye tracking in virtual reality within pediatric ophthalmology. [J Pediatr Ophthalmol Strabismus. 20XX;X(X):XX-XX.].

Retinal integrity in human babesiosis: a pilot study

BackgroundPrior case reports and animal studies have reported on potential ophthalmologic complications of babesiosis, but this issue has not previously been addressed in a cohort of patients with babesiosis. This cross-sectional descriptive pilot study evaluated the retinas of patients with acute babesiosis to determine if retinal abnormalities are a feature of the disease.MethodsWe screened all patients admitted to Yale New Haven Hospital with laboratory confirmed babesiosis during the summer of 2023 and obtained informed consent. Patients were interviewed and underwent pupil dilation and a retinal examination using an indirect ophthalmoscope. Demographic and clinical information were obtained by questionnaire and through chart review.ResultsTen patients underwent retinal eye exams with results that were generally unremarkable. No study patients showed any signs of retinal inflammation, infection, retinal bleeding, retinal tears, or abnormal vessel formation that could be attributed to infection.ConclusionThis small study did not find evidence of retinopathy in patients with babesiosis. Further studies with larger populations, repeated exams, and long term follow up will further elucidate the potential small vessel complications of human babesiosis.

Research on segmentation model of optic disc and optic cup in fundus

BackgroundGlaucoma is a worldwide eye disease that can cause irreversible vision loss. Early detection of glaucoma is important to reduce vision loss, and retinal fundus image examination is one of the most commonly used solutions for glaucoma diagnosis due to its low cost. Clinically, the cup-disc ratio of fundus images is an important indicator for glaucoma diagnosis. In recent years, there have been an increasing number of algorithms for segmentation and recognition of the optic disc (OD) and optic cup (OC), but these algorithms generally have poor universality, segmentation performance, and segmentation accuracy.MethodsBy improving the YOLOv8 algorithm for segmentation of OD and OC. Firstly, a set of algorithms was designed to adapt the REFUGE dataset’s result images to the input format of the YOLOv8 algorithm. Secondly, in order to improve segmentation performance, the network structure of YOLOv8 was improved, including adding a ROI (Region of Interest) module, modifying the bounding box regression loss function from CIOU to Focal-EIoU. Finally, by training and testing the REFUGE dataset, the improved YOLOv8 algorithm was evaluated.ResultsThe experimental results show that the improved YOLOv8 algorithm achieves good segmentation performance on the REFUGE dataset. In the OD and OC segmentation tests, the F1 score is 0.999.ConclusionsWe improved the YOLOv8 algorithm and applied the improved model to the segmentation task of OD and OC in fundus images. The results show that our improved model is far superior to the mainstream U-Net model in terms of training speed, segmentation performance, and segmentation accuracy.

Long-Term Sulfonylurea Use and Impaired Awareness of Hypoglycemia Among Patients With Type 2 Diabetes in Taiwan.

We undertook a study to investigate the relationship between duration of medication use and prevalence of impaired awareness of hypoglycemia (IAH) among patients with insulin-treated or sulfonylurea-treated type 2 diabetes in Taiwan. A total of 898 patients (41.0% insulin users, 65.1% sulfonylurea users; mean [SD] age = 59.9 [12.3] years, 50.7% female) were enrolled in pharmacies, clinics, and health bureaus of Tainan City, Taiwan. Presence of IAH was determined with Chinese versions of the Gold questionnaire (Gold-TW) and Clarke questionnaire (Clarke-TW). Sociodemographics, disease and treatment histories, diabetes-related medical care, and health status were collected. We used multiple logistic regression models to assess the relationship between duration of medication use and IAH. Overall IAH prevalence was 41.0% (Gold-TW) and 28.2% (Clarke-TW) among insulin users, and 65.3% (Gold-TW) and 51.3% (Clarke-TW) among sulfonylurea users. Prevalence increased with the duration of sulfonylurea use, whereas it decreased with the duration of insulin use. After controlling for potential confounders, 5 or more years of sulfonylurea use was significantly associated with 3.50-fold (95% CI, 2.39-5.13) and 3.06-fold (95% CI, 2.11-4.44) increases in the odds of IAH based on the Gold-TW and Clarke-TW criteria, respectively. On the other hand, regular blood glucose testing and retinal examinations were associated with reduced odds in both insulin users and sulfonylurea users. The prevalence of IAH was high among patients using sulfonylureas long term, but the odds of this complication were attenuated for those who received regular diabetes-related medical care. Our study suggests that long-term sulfonylurea use and irregular follow-up increase risk for IAH. Further prospective studies are needed to confirm the observed associations.Annals Early Access article.

Improving diabetic retinopathy screening at the point of care: integrating telemedicine to overcome current challenges

ObjectiveTo investigate the utility of point of care screening of diabetic retinopathy (DR) and the impact of a telemedicine program to overcome current challenges.MethodsThis was a retrospective study on people with type 2 diabetes mellitus (T2DM) who were screened for DR using the single-field non-mydriatic fundus photography at the point of care during routine follow-up visits at endocrinology clinic. Retinal images were uploaded and sent to a retina specialist for review. Reports indicating retinopathy status and the need for direct retinal examination were transmitted back to the endocrinology clinic. All patients were informed about DR status and, if needed, referred to the retina specialist for direct retinal examination.ResultsOf the 1159 individuals screened for DR, 417 persons (35.98%) were screen-positive and referred to the retina specialist for direct retinal examination. A total of 121 individuals (29.01%) underwent direct retinal examination by the specialist. Diabetes macular edema (DME) was detected in 12.1%. In addition, non-proliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR) were detected in 53.4% and 2.6% of the patients, respectively.ConclusionIntegrating DR screening program at the point of care at the secondary care services improves the rate of DR screening as well as detection of sight threatening retinopathy and provides the opportunity for timely intervention in order to prevent advanced retinopathy in people with T2DM.

Circulatory Failure in the Central Retinal Artery during Medial Orbital Wall Blow-out Fracture Repair

Purpose: We report a case of visual impairment due to circulatory failure in the central retinal artery during blow-out fracture repair.Case summary: A 16-year-old male with no underlying disease was diagnosed with a trapdoor type medial orbital wall blow-out fracture after a motorcycle accident and underwent blow-out fracture repair. During the surgery, his left eye was nearly completely dilated. Postoperatively, the visual acuity in the left eye was hand motion and there was ptosis of the left upper eyelid. Concerned with the possibility of orbital implant compression, computed tomography was performed immediately and a second operation was performed. However, there was no direct compression originating from the intraocular implant or any signs of active bleeding. The following day, optical coherence tomography and fluorescein angiography revealed a cherry-red spot on the central fovea with edema of the inner retinal layer and delayed arterial circulation. Under a diagnosis of incomplete central retinal artery occlusion, the patient was treated with intraocular pressure-lowering eye drops and intravenous mannitol. Despite prompt intervention, the visual acuity of the left eye did not improve beyond 0.04 at the 2-year follow-up.Conclusions: When there is visual impairment and pupillary dilation after blow-out fracture repair, we should consider not only compressive factors but also the possibility of central retinal artery occlusion or circulatory failure. In such cases, retinal examinations should be done to assess the retinal blood flow and enable early detection of any complications allowing prompt appropriate intervention.

Clinical and Optical Coherence Tomography Features of Subretinal Fibrin Glue after Glue-Assisted Vitrectomy for Rhegmatogenous Retinal Detachment Repair. GUARD Study – Report 3:

Purpose: To highlight the clinical and optical coherence tomography (OCT) features of subretinal fibrin glue and its resolution over time in patients who have undergone glue- assisted retinopexy for Rhegmatogenous Retinal Detachments (RRD). Methods: A report of 2 cases with subretinal migration of fibrin glue. Both the cases were assessed with clinical examination, serial fundus photos and serial OCT scans through the area of subretinal fibrin immediately after surgery, at 1 week, 2 weeks and at 6 weeks. Results: In both the cases of intraoperative subretinal glue migration during glue-assisted vitrectomy for RRD repair, the subretinal glue had a characteristic appearance and course of evolution. On examination and color photography, the glue had an amorphous whitish appearance with wispy edges. This corresponded to subretinal hyperreflective material (SHRM) on OCT with a layered appearance. By two weeks after surgery, the subretinal glue demonstrated substantial regression on retinal examination and on OCT scans. At 6 weeks visit, the entire glue was noted to be resorbed along with an intact photoreceptor outer segments/Ellipsoid Zone layer Conclusion: In summary, this report describes the clinical and OCT appearance of subretinal migration of fibrin glue. Subretinal fibrin appears whitish on examination and corresponds to layered SHRM without shadowing on OCT. It appears to resorb spontaneously within weeks with apparent recovery of the overlying photoreceptors.

Pregnancy and diabetic retinopathy

Background: An increase in the worldwide prevalence of diabetes, especially among younger populations, has led to a higher prevalence of pre-existing diabetes among pregnant women. The precise mechanisms underlying the development or progression of diabetic retinopathy (DR) during pregnancy are not entirely understood. This narrative review incorporates all available data to offer fresh insights into the pathogenesis and mechanisms of the pregnancy-induced development and/or progression of DR. Moreover, the author aims to offer clinical recommendations for DR both before conception and during pregnancy to appropriately counsel these susceptible patients. Methods: A literature search was performed using various combinations of the following keywords: diabetes, pregnancy, diabetic retinopathy, ocular, eye, retina, microangiopathy, mechanism, pathophysiology, hyperglycemia, hypoxia, neovascularization, growth factors, immune system, blood flow, and recommendations. The search was conducted using PubMed/MEDLINE, ISI Web of Science, Scopus, and Google Scholar, and only English articles published from January 1, 2020, to December 31, 2023, involving human participants, were considered. The International Diabetes Federation Diabetes Atlas website was searched for clinical recommendations. Results: Pregnancy-induced hyperglycemia, blood flow changes, growth factors, and the immune system play important roles in the development and progression of DR. Hyperglycemia leads to significant stress on the capillary endothelium through increased glucose flux via the polyol and hexosamine pathways, activation of protein kinase C, and increased formation of advanced glycation end-products. These pathways act in several ways that may lead to increased oxidative stress, inflammation, and vascular blockage. Thus, eye examinations are crucial before, during, and up to 12 months after pregnancy. Individuals with severe non-proliferative and proliferative DR should gradually decrease their blood glucose levels to near-normal levels over a period of 6 months before conception. Statins and medications inhibiting the renin–angiotensin system should be discontinued before pregnancy or at the initial antenatal visit if they are still being used. Retinal examinations should be performed shortly after conception and during the first trimester using tropicamide eye drops and digital imaging. Subsequent examinations should be scheduled based on DR severity at the initial examination. Conclusions: While the precise mechanism underlying the progression of DR during pregnancy remains uncertain, the available literature suggests that pregnancy-induced hyperglycemia, blood flow changes, growth factors, and the immune system play important roles in its development and progression. Pregnant women with diabetic eye manifestations benefit from the expertise of multidisciplinary teams comprising ophthalmologists, diabetologists, and gynecologists to improve both maternal and perinatal outcomes. Moreover, postpartum follow-up requires special attention.

Comparing the Implementation of Different Diabetic Retinopathy Screening Models in Primary Health Care Settings in Northern India: Pragmatic Three-Arm Observational Study

Introduction: Early screening is recommended to prevent vision impairment (VI) and blindness globally due to diabetic retinopathy (DR). We aim to analyze the factors influencing the implementation of DR screening models in primary healthcare facilities. Methods: A pragmatic three-arm observational study will be conducted in the district of Mohali in Punjab, India. The study will compare three equal-sized groups with type 2 diabetes mellitus (T2DM) at age 30 and above. The T2DM participants and healthcare providers (HCPs) will be interviewed to identify the barriers to retinal examinations in primary healthcare settings. The study includes a comprehensive economic evaluation to determine the cost-effectiveness of implementing different DR screening models in primary health settings. The present study will use the RE-AIM framework (reach, effectiveness, adoption, implementation, and maintenance), to assess the implementation of two DR screening interventions and the extent of variation in outcomes. Qualitative and quantitative data collected from participants and research team observations will be examined to report on the five RE-AIM domains. Discussion: A screening program should ensure early detection and referral for DR treatment before it results in irreversible vision loss. However, understanding the problems of accessing DR screening and estimating the cost-effectiveness of such programs in a primary health setting is important before allocating public health resources.

Prevalence of retinal pathologies in people over 60 years: the Tehran Geriatrics Eye Study.

To determine the prevalence of some retinal pathologies in people over 60y and their association with demographic and ocular factors. A cross-sectional study was conducted in Tehran using multistage cluster sampling. After selecting subjects aged 60 and over, optometric, and ophthalmic examinations were done. For retinal examination, a 90 D lens was used and indirect ophthalmoscopy was performed after instilling tropicamide drops. Biometry was done using the IOL Master for all participants. Of 3791 people that were invited through cluster sampling, 3310 participated in the study (response rate=82%). The prevalence of retinal pigmented epithelium (RPE) change, drusen, geographic atrophy (GA), hypertensive retinopathy (HTR), nonproliferative diabetic retinopathy (NPDR), proliferative diabetic retinopathy (PDR), choroidal neovascularization (CNV), central retinal artery occlusion (CRAO), myopic retinopathy (MR), branch retinal vein occlusion (BRVO), and central retinal vein occlusion (CRVO) was 27.42%, 11.08%, 4.52%, 3.03%, 4.05%, 0.54%, 0.82%, 0.39%, 0.20%, 0.49%, and 0.19%, respectively. After removing the effect of age, the odds of NPDR were 1.68 times higher in women compared to men (P=0.014). After removing the effect of sex, the odds of drusen, RPE change, GA, CNV, BRVO, and CRVO increased with age. There is a higher prevalence of RPE change, drusen, GA, CNV and a lower prevalence of MR and CRAO in the elderly population of Tehran aged over 60y compared to global average values. Considering the correlation of most of the diseases with age and their effects on vision, attention should be paid to these diseases and the related screening programs to prevent vision impairment.