Diabetic Retinopathy in Italy: Epidemiology Data and Telemedicine Screening Programs

Patients with Type 2 Diabetes, Higher Blood Pressure, and Infrequent Fundus Examinations Have a Higher Risk of Sight-Threatening Retinopathy

Background: Diabetic retinopathy (DR) is the most common cause of preventable blindness among working-age adults. This study aimed to evaluate the impact of the regularity of fundus examinations and risk factor control in patients with type 2 diabetes (T2DM) on the prevalence and severity of DR. Methods: One hundred and fifty-six T2DM patients were included in this cross-sectional study. Results: In this sample, the prevalence of DR was 46.2%. Patients with no DR mainly did not examine the fundus regularly, while most patients with mild/moderate nonproliferative DR (NPDR) underwent a fundus examination regularly. In 39.7% of patients, this was the first fundus examination due to diabetes, and 67% of them had sight-threatening DR (STDR). Diabetes duration (p = 0.007), poor glycemic control (HbA1c) (p = 0.006), higher systolic blood pressure (SBP) (p < 0.001), and diastolic blood pressure (DBP) (p = 0.002) were the main predictors of DR. However, the impact of SBP (AOR 1.07, p = 0.003) and DBP (AOR 1.13, p = 0.005) on DR development remained significant even after adjustment for diabetes duration and HbA1c. The DR prevalence was higher in patients with higher blood pressure (≥130/80 mmHg) than in those with target blood pressure (<130/80 mmHg) (p = 0.043). None of the patients with target blood pressure had STDR. The peaks in SBP and DBP were observed in T2DM with DR and the first fundus examination due to diabetes. Conclusions: In this T2DM sample, DR prevalence was very high and strongly related to blood pressure and a lack of regular fundus examinations. These results indicate the necessity of establishing systematic DR screening in routine diabetes care and targeting blood pressure levels according to T2DM guidelines.

Obstructive sleep apnea is not associated with diabetic retinopathy in diabetes: a prospective case-control study

PURPOSE

Diabetic retinopathy (DR) is the most common ocular complication of type 2 diabetes mellitus (T2D) and is associated with diabetes duration, glycemic control, and hypertension (HTN). Obstructive sleep apnea (OSA) is frequent in T2D and is associated with poor glycemic control. However, it is unclear if there is an association between OSA and DR. This study aimed to assess whether or not the presence of OSA in patients with T2D was associated with DR.

METHODS

In this prospective case-control study, consecutive patients with DM attending the ophthalmology clinics were recruited to include patients with DR (cases) and without DR (controls). OSA was diagnosed by attended polysomnography (PSG). Blood pressure and a fasting morning blood sample, including glycosylated hemoglobin (HbA1c), were recorded. Patients were matched for age, body mass index (BMI), gender, and T2D duration.

RESULTS

Thirty diabetic patients with DR were matched with 30 controls. In all patients, the prevalence of moderate-to-severe OSA was 57%. In the logistic regression analysis, DR was associated with increased HbA1c (OR 2.63, 95% CI 1.35-5.16, p = 0.004) but not with any PSG parameter. In the DR group, PSG parameters were not associated with the severity of ocular disease (non-proliferative, proliferative, presence/absence of macular edema). The proliferative aspect of DR was correlated with age (p = 0.017). DR occurred more frequently in uncontrolled diabetes compared to well-controlled diabetes (80% vs 38%, p = 0.029).

CONCLUSIONS

In patients with T2D, the presence of DR is not associated with OSA, but with poorly controlled T2D.

The Narrative Medicine Approach in the Treatment of Diabetic Macular Edema: An Italian Experience

The study retraces the healthcare pathway of patients affected by diabetic macular edema (DME) through the direct voice of patients and caregivers by using a “patient journey” and narrative method approach. The mapping of the patient’s journey was developed by a multidisciplinary board of health professionals and involved four Italian retina centers. DME patients on intravitreal injection therapy and caregivers were interviewed according to the narrative medicine approach. Narratives were analyzed through a quali-quantitative tool, as set by the narrative medicine method. The study involved four specialized retina centers in Italy and collected a total of 106 narratives, 82 from DME patients and 24 from caregivers. The narratives reported their difficulty in identifying the correct pathway of care because of a limited awareness of diabetes and its complications. Patients experienced reduced autonomy due to ocular complications. In the treatment of diabetes and its complications, a multidisciplinary approach currently appears to be missing. DME reduces the quality of life of affected patients. The narrative medicine approach offers qualitative and emotional patient-guided information. The patient journey provides all of those involved in the management of DME with flowcharts to refer to, identifying the critical points in the healthcare journey of DME patients to improve the management of the disease.

Handheld Fundus Camera for Diabetic Retinopathy Screening: A Comparison Study with Table-Top Fundus Camera in Real-Life Setting

The aim of the study was to validate the performance of the Optomed Aurora^® handheld fundus camera in diabetic retinopathy (DR) screening. Patients who were affected by diabetes mellitus and referred to the local DR screening service underwent fundus photography using a standard table-top fundus camera and the Optomed Aurora^® handheld fundus camera. All photos were taken by a single, previously unexperienced operator. Among 423 enrolled eyes, we found a prevalence of 3.55% and 3.31% referable cases with the Aurora^® and with the standard table-top fundus camera, respectively. The Aurora^® obtained a sensitivity of 96.9% and a specificity of 94.8% in recognizing the presence of any degree of DR, a sensitivity of 100% and a specificity of 99.8% for any degree of diabetic maculopathy (DM) and a sensitivity of 100% and specificity of 99.8% for referable cases. The overall concordance coefficient k (95% CI) was 0.889 (0.828–0.949) and 0.831 (0.658–1.004) with linear weighting for DR and DM, respectively. The presence of hypertensive retinopathy (HR) was recognized by the Aurora^® with a sensitivity and specificity of 100%. The Optomed Aurora^® handheld fundus camera proved to be effective in recognizing referable cases in a real-life DR screening setting. It showed comparable results to a standard table-top fundus camera in DR, DM and HR detection and grading. The Aurora^® can be integrated into telemedicine solutions and artificial intelligence services which, in addition to its portability and ease of use, make it particularly suitable for DR screening.

Mobile Telemedicine Screening for Diabetic Retinopathy Using Nonmydriatic Fundus Photographs in Burgundy: 11 Years of Results

We analyzed the results of mobile screening for diabetic retinopathy (DR) using retinal photographs, comparing these results between rural and periurban areas, and before and after the first national COVID-19 pandemic lockdown. The Burgundy Union Régionale des Professionnels de Santé (URPS) has organized an annual DR screening since 2004. The examination, performed by an orthoptist, consisted of taking the patient's history, intraocular pressure measurement, and taking retinal photographs. After remote transmission, the examinations were interpreted by participating ophthalmologists at the Dijon University Hospital. In September 2016, the screening was open to periurban townships. In 11 years, 10,220 patients were screened: 1,420 patients (13.9%) had DR of any type, with an average age of 68.5 (±11.3) years, and 59.2% were men. These patients had a statistically significantly higher glycated hemoglobin level (7.4% vs. 7.0%) and a longer duration of diabetes (13.8 vs. 9.3 years) than patients without DR. When comparing rural and periurban areas and periods before and after the beginning of the COVID-19 pandemic, we did not find any significant difference in the screening results. The results of this study are in line with the average findings of similar studies comparing screening strategies for DR. The early detection of DR can benefit from mobile telemedicine screening, identifying a considerable number of patients at an elevated risk, especially in rural areas where access to ophthalmological care is limited.

TREND database: Retinal images of healthy young subjects visualized by a portable digital non-mydriatic fundus camera

Topological characterization of the Retinal microvascular nEtwork visualized by portable fuNDus camera (TREND) is a database comprising of 72 color digital retinal images collected from the students of the Faculty of Medicine at the University of Montenegro, in the period from February 18th to March 11th 2020. The database also includes binarized images of manually segmented microvascular networks associated with each raw image. The participant demographic characteristics, health status, and social habits information such as age, sex, body mass index, smoking history, alcohol use, as well as previous medical history was collected. As proof of the concept, a smaller set of 10 color digital fundus images from healthy older participants is also included. Comparison of the microvascular parameters of these two sets of images demonstrate that digital fundus images recorded with a hand-held portable camera are able to capture the changes in patterns of microvascular network associated with aging. The raw images from the TREND database provide a standard that defines normal retinal anatomy and microvascular network geometry in young healthy people in Montenegro as it is seen with the digital hand-held portable non-mydriatic MiiS HORUS Scope DEC 200.This knowledge could facilitate the application of this technology at the primary level of health care for large scale telematic screening for complications of chronic diseases, such as hypertensive and diabetic retinopathy. In addition, it could aid in the development of new methods for early detection of age-related changes in the retina, systemic chronic diseases, as well as eye-specific diseases. The associated manually segmented images of the microvascular networks provide the standard that can be used for development of automatic software for image quality assessment, segmentation of microvascular network, and for computer-aided detection of pathological changes in retina. The TREND database is freely available at https://doi.org/10.5281/zenodo.4521043.

Impact of Intersecting Systems of Oppression on Diabetic Retinopathy Screening Among Those Who Identify as Women of Low Socioeconomic Status: Protocol for a Convergent Mixed Methods Study

Background

By 2025, 5 million Canadians will be diagnosed with diabetes, and women from lower socioeconomic groups will likely account for most new diagnoses. Diabetic retinopathy is a primary vision complication of diabetes and a leading cause of blindness among adults, with 26% prevalence among women. Tele-retina is a branch of telemedicine that delivers eye care remotely. Screening for diabetic retinopathy has great potential to reduce the incidence of blindness, yet there is an adverse association among screening, income, and gender.

Objective

We aim to explore gender disparity in the provision of tele-retina program services for diabetic retinopathy screening in a cohort of women of low socioeconomic status (SES) receiving services in South Riverdale Community Health Centre (SRCHC) between 2014 and 2019.

Methods

Using a convergent mixed methods design, we want to understand patients’, providers’, administrators’, and decision makers’ perceptions of the facilitators and barriers associated with the implementation and adoption of tele-retina. Multivariate logistic regression will be utilized to assess the association among client characteristics, referral source, and diabetic retinopathy screening. Guided by a grounded theory approach, systematic coding of data and thematic analysis will be utilized to identify key facilitators and barriers to the implementation and adoption of tele-retina.

Results

For the quantitative component, we anticipate a cohort of 2500 patients, and we expect to collect data on the overall patterns of tele-retina program use, including descriptions of program utilization rates (such as data on received and completed diabetic retinopathy screening referrals) along the landscape of patient populations receiving these services. For the qualitative component, we plan to interview up to 21 patients and 14 providers, administrators, and decision makers, and to conduct up to 14 hours of observations alongside review of relevant documents. The interview guide is being developed in collaboration with our patient partners. Through the use of mixed methods research, the inquiry will be approached from different perspectives. Mixed methods will guide us in combining the rich subjective insights on complex realities from qualitative inquiry with the standard generalizable data that will be generated through quantitative research. The study is under review by the University Health Network Research Ethics Board (19-5628). We expect to begin recruitment in winter 2021.

Conclusions

In Ontario, the screening rate for diabetic retinopathy among low income groups remains below 65%. Understanding the facilitators and barriers to diabetic retinopathy screening may be a prerequisite in the development of a successful screening program. This study is the first Ontario study to focus on diabetic retinopathy screening practices in women of low SES, with the aim to improve their health outcomes and revolutionize access to quality care.

International Registered Report Identifier (IRRID)

PRR1-10.2196/23492

Challenges and opportunities of digital health in a post-COVID19 world

Digital health as a rapidly growing medical field relies comprehensively on human health data. Conventionally, the collection of health data is mediated by officially diagnostic instruments, operated by health professionals in clinical environments and under strict regulatory conditions. Mobile health, telemedicine, and other smart devices with Internet connections are becoming the future choices for collecting patient information. Progress of technologies has facilitated smartphones, wearable devices, and miniaturized health-care devices. These devices allow the gathering of an individual's health-care information at the patient's home. The data from these devices will be huge, and by integrating such enormous data using Artificial Intelligence, more detailed phenotyping of disease and more personalized medicine will be realistic. The future of medicine will be progressively more digital, and recognizing the importance of digital technology in this field and pandemic preparedness planning has become urgent.

Remote health diagnosis and monitoring in the time of COVID-19

Coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is rapidly spreading across the globe. The clinical spectrum of SARS-CoV-2 pneumonia requires early detection and monitoring, within a clinical environment for critical cases and remotely for mild cases, with a large spectrum of symptoms. The fear of contamination in clinical environments has led to a dramatic reduction in on-site referrals for routine care. There has also been a perceived need to continuously monitor non-severe COVID-19 patients, either from their quarantine site at home, or dedicated quarantine locations (e.g. hotels). In particular, facilitating contact tracing with proximity and location tracing apps was adopted in many countries very rapidly. Thus, the pandemic has driven incentives to innovate and enhance or create new routes for providing healthcare services at distance. In particular, this has created a dramatic impetus to find innovative ways to remotely and effectively monitor patient health status. In this paper, we present a review of remote health monitoring initiatives taken in 20 states during the time of the pandemic. We emphasize in the discussion particular aspects that are common ground for the reviewed states, in particular the future impact of the pandemic on remote health monitoring and consideration on data privacy.

The role of tele-ophthalmology in diabetic retinopathy screening

Diabetic retinopathy (DR) is the leading cause of legal blindness in the United States. Considering the increasing incidence of DR, it is extremely important to detect the most cost-effective tools for DR screening, so as to manage this surge in demand and the socioeconomic burden it places on the health care system. Despite the advances in retinal imaging, analysis techniques are still superseded by expert ophthalmologist interpretation. Teleophthalmology presents an immense opportunity, with high rates of sensitivity and specificity, to manage the steadily increasing demand for eye care of patients with diabetes, but challenges remain in the delivery of practical, viable, and clinically proven solutions.

Benefits of micronutrient supplementation for reducing the risk of wet age-related macular disease and diabetic retinopathy

Age-related macular disease and diabetic retinopathy are chronic degenerative diseases characterised by progressive visual impairment. In Europe, age-related macular disease accounts for over 15% of blindness in adults over 50 years of age, and although the burden of diabetic retinopathy in terms of vision impairment is lower, vision loss associated with diabetic retinopathy is increasing with the rising prevalence of diabetes mellitus and the ageing of the population. Late-stage age-related macular disease can be subdivided into dry (non-neovascular) or wet (neovascular or exudative) forms. The large Age-Related Eye Disease Study 2 showed that supplementation with antioxidant nutrients reduces choroids neovascularisation and reduces the risk of progression of neovascular age-related macular disease. Antioxidant micronutrient supplements have also shown promising results in preventing the pathogenesis of retinopathy in animal models of diabetes. Age-related macular disease and diabetic retinopathy are understood to share some common pathophysiological characteristics, suggesting that micronutrients have an important role in ocular health in both conditions. This article will review the current evidence for the utility of micronutrients in preventing the development and progression of neovascular age-related macular disease and diabetic retinopathy.

miR-7 Reduces High Glucose Induced-damage Via HoxB3 and PI3K/AKT/mTOR Signaling Pathways in Retinal Pigment Epithelial Cells

BACKGROUND

Diabetic retinopathy (DR) is a common complication of diabetes. This study investigated the effect of miR-7 in the regulation of cell proliferation via the HoxB3 gene and PI3K/AKT/mTOR signaling pathways in DR.

METHODS

Human retinal pigment epithelial cell line (ARPE-19) cultured in normal medium (Control) and high glucose medium (25mM glucose, HG) was transfected with mimics NC (HG+ mimics NC), miR-7 mimics (HG+miR-7 mimics), inhibitor NC (HG+ inhibitor NC), and miR-inhibitor (HG+miR-7 inhibitor). The cells were assayed for viability, apoptosis, and expression of genes.

RESULTS

HG reduced cell viability and increased apoptosis. However, miR-7 mimics reduced the apoptosis. PCR results showed that miR-7 was significantly upregulated after transfection with miR-7 mimics. The expression of Hoxb3, mTOR, p-PI3K, and p- AKT was significantly downregulated at mRNA and protein levels after miR-7 mimics transfection, while no difference was observed for PI3K and AKT expression.

CONCLUSION

Our findings demonstrate that miR-7 regulates the growth of retinal epithelial cells through various pathways and is a potential therapeutic target for the prevention and treatment of diabetic retinopathy.

Non-mydriatic fundus camera screening with diagnosis by telemedicine for diabetic retinopathy patients with type 1 and type 2 diabetes: a hospital-based cross-sectional study

BACKGROUND

Diabetic retinopathy (DR) is considered the fifth leading cause of visual impairment worldwide and is associated with a huge social and economic burden.

OBJECTIVE

Describe the practicality of non-mydriatic funduscopic screening photography for the detection of DR among patients with type 1 and type 2 diabetes.

DESIGN

Cross-sectional hospital-based study.

SETTING

Diabetes center, Riyadh.

PATIENTS AND METHODS

Between July and December 2017, patients with diabetes and aged ≥18 years were selected by systematic random sampling from the University Diabetes Center. Fundoscopic eye examination was performed using the TRC-NW8 non-mydriatic camera, which performs ocular coherence tomography (OCT) to detect macular edema. Using telemedicine, pictures were graded by a retinal-specialized ophthalmologist using the international clinical DR disease severity scale. Patients were classified according to the type and severity of DR.

MAIN OUTCOME MEASURES

Detection and classification of DR.

SAMPLE SIZE

978 Saudi patients with diabetes.

RESULTS

Of 426 (43.5%) patients with DR, 370 had nonproliferative DR and 55 had proliferative DR. Nineteen (1.9%) had macular edema. The most important risk factors for DR were longer diabetes duration and poor glycemic control. Both older age and insulin use contributed to the higher prevalence of DR and macular edema. DR was more common among type 1 patients at 55.4% compared with 49% among type 2 patients. In addition, more females had macular edema (57.1% versus 42.9% among males). Nine patients with macular edema (47.3%) had hypertension while 154 of 426 patients with DR (36.2%) had hypertension.

CONCLUSION

Non-mydriatic funduscopic screening photography was practical and useful for the detection of DR in patients with type 1 and type 2 diabetes.

LIMITATIONS

Conducted in a single center.

CONFLICT OF INTEREST

None.

Retinopathy among Chinese subjects with type 2 diabetes mellitus in Shanghai: A community-based follow-up study

OBJECTIVE

To determine the incidence, progression, and regression rates of diabetic retinopathy (DR), as well as their associated factors, in Chinese type 2 diabetic patients.

METHODS

Diabetic patients who participated in a previous survey were recruited for a 1-year follow-up study. Nonmydriatic fundus photographs were acquired to assess the severity of DR as per the International Clinical Diabetic Retinopathy Disease Severity Scale (2002). Factors that potentially influence DR outcomes, including its incidence, progression, and regression, were identified via statistical analyses.

RESULTS

We initially recruited 2453 subjects, among whom 2331 were followed and included in the final analysis. The incidences of new and progressed (ie, ≥2 scale steps) DR were 10.6% and 6.1%, respectively. Moreover, 7.3% of patients with established DR at baseline experienced complete regression. Multivariate logistic regression analysis revealed that high glycosylated haemoglobin (HbA1c) (odds ratio [OR] = 1.50, P = .021) and hyperlipidaemia (OR = 1.46, P = .025) were independent predictors of DR development, high HbA1c (OR = 4.16, P = .027) and macroalbuminuria (OR = 5.60, P = .010) predicted DR progression, and low HbA1c (OR = 0.20, P = .001) and low triglyceride levels (OR = 0.34, P = .026) were associated with DR regression.

CONCLUSIONS

Albumin and HbA1c levels should be closely monitored as signs of progressive retinal damage in diabetic subjects. Optimized control of glucose and triglyceride levels is vital for reducing the incidence of DR or promoting its regression in afflicted patients.

Diabetic retinopathy and age-related macular degeneration: a survey of pharmacoutilization and cost in Calabria, Italy

The aged population is constantly growing, thus fostering an increase in age-dependent diseases. Among these, diabetic retinopathy (DR) along with age-related macular degeneration entails progressive vision loss. Since such conditions are associated with the proliferation of novel vessels, their pharmacotherapeutic management consists of the intravitreal injection of anti-vascular endothelial growth factor drugs, able to hinder the driving of vascular proliferation prompted by vascular endothelial growth factor. The humanized anti-vascular endothelial growth factor monoclonal antibody ranibizumab provided evidence for efficacy in several trials, hence earning approval by the US Food and Drug Administration for therapeutic use in all the stages of DR. Due to the lack of epidemiologic and pharmacoeconomic evaluation in the local Calabria Region context, the present retrospective observational study focused on prevalence of DR and age-related macular degeneration, treatment and cost of therapy with ranibizumab in 870 patients arriving to clinical observation at the "Mater Domini" University Hospital in Calabria, Italy from January 2014 to June 2017. Data were extracted from the database of ophthalmology ward and subjected to statistical analysis. The results suggest that the most frequent retinal diseases are age-related macular degeneration and DR and that the use of ranibizumab has been decreasing over the 4-year study period together with the associated cost per patient which was similar for both disorders. Therefore, appropriateness of treatment with drugs other than ranibizumab needs to be assessed in this setting and deep monitoring of pharmacologic treatment for retinal diseases is necessary to prevent or delay visual acuity decrease and complete vision loss. Study procedures were performed in accordance with the "Mater Domini" University Hospital ethical standards of the responsible committee on human experimentation.

Fractal characterization of retinal microvascular network morphology during diabetic retinopathy progression

OBJECTIVE

The study aimed to characterize morphological changes of the retinal microvascular network during the progression of diabetic retinopathy.

METHODS

Publicly available retinal images captured by a digital fundus camera from DIARETDB1 and STARE databases were used. The retinal microvessels were segmented using the automatic method, and vascular network morphology was analyzed by fractal parametrization such as box-counting dimension, lacunarity, and multifractals.

RESULTS

The results of the analysis were affected by the ability of the segmentation method to include smaller vessels with more branching generations. In cases where the segmentation was more detailed and included a higher number of vessel branching generations, increased severity of diabetic retinopathy was associated with increased complexity of microvascular network as measured by box-counting and multifractal dimensions, and decreased gappiness of retinal microvascular network as measured by lacunarity parameter. This association was not observed if the segmentation method included only 3-4 vessel branching generations.

CONCLUSIONS

Severe stages of diabetic retinopathy could be detected noninvasively by using high resolution fundus photography and automatic microvascular segmentation to the high number of branching generations, followed by fractal analysis parametrization. This approach could improve risk stratification for the development of microvascular complications, cardiovascular disease, and dementia in diabetes.

Preventing blindness and visual impairment in Europe: What do we have to do?

Severe visual impairment and blindness are significant public health problems worldwide. Four-fifths of cases of blindness can be prevented or cured. The World Health organisation's 'Universal Eye Health: A Global Action Plan 2014-2019' and the European Society of Ophthalmology's Pilot Committee on Public Eye Health are aiming to decrease the prevalence of blindness in Europe and around the world. Starting discussions addressing possible actions and advocacies to improve current circumstances in public eye health is a common task of ophthalmologists and public health specialists in Europe.

Metabolic memory in mitochondrial oxidative damage triggers diabetic retinopathy

Background

Diabetic retinopathy (DR) is a microvascular complication induced by high blood glucose. This study was conducted to investigate the effect of metabolic memory on mitochondrial oxidative damage-induced DR.

Methods

Rat retinal endothelial cells (rRECs) were isolated from SD rats and treated with high glucose (20 mM) for various times and then cultured in normal glucose (5.6 mM) medium for 2 days. The cells were assayed for the expression of respiratory chain complexes cytochrome c oxidase subunit 1 (CO1) and NADPH-1 using RT-PCR, mitochondrial membrane potentials and reactive oxygen species (ROS) production using flow cytometry and apoptosis using Annexin V/PI flow cytometry.

Results

rRECs displayed like short spindles after cultured for 9–10 days and reached 100% confluency. Compared with the control grown in normal glucose (5.6 mM) medium, rRECs exposed to high glucose medium for 3, 12 and 24 h had significantly increased mRNA levels of CO1 and NAPDH-1 even after being shifted back to normal glucose medium. They also had lower mitochondrial membrane potential (89.13% vs 78.21%, p < 0.05), cytochrome C level (1 in control vs 0.25 after 24 h exposure to high glucose, p < 0.05 and higher ROS production (2.77% in control vs 9.00% after 12 h exposure to high glucose, p < 0.05) and apoptosis (7.15% in control vs and 29.91% after 24 h exposure to high glucose, p < 0.05).

Conclusion

It is likely that mitochondrial oxidative damage triggers metabolic memory via ROS overproduction, leading to diabetic retinopathy.

SS, Dhawan B, Palsule A, Kumar D, Chandel S, Sood S. Sensitivity and specificity of automated analysis of single-field non-mydriatic fundus photographs by Bosch DR Algorithm-Comparison with mydriatic fundus photography (ETDRS) for screening in undiagnosed diabetic retinopathy

Diabetic retinopathy (DR) is a leading cause of blindness among working-age adults. Early diagnosis through effective screening programs is likely to improve vision outcomes. The ETDRS seven-standard-field 35-mm stereoscopic color retinal imaging (ETDRS) of the dilated eye is elaborate and requires mydriasis, and is unsuitable for screening. We evaluated an image analysis application for the automated diagnosis of DR from non-mydriatic single-field images. Patients suffering from diabetes for at least 5 years were included if they were 18 years or older. Patients already diagnosed with DR were excluded. Physiologic mydriasis was achieved by placing the subjects in a dark room. Images were captured using a Bosch Mobile Eye Care fundus camera. The images were analyzed by the Retinal Imaging Bosch DR Algorithm for the diagnosis of DR. All subjects also subsequently underwent pharmacological mydriasis and ETDRS imaging. Non-mydriatic and mydriatic images were read by ophthalmologists. The ETDRS readings were used as the gold standard for calculating the sensitivity and specificity for the software. 564 consecutive subjects (1128 eyes) were recruited from six centers in India. Each subject was evaluated at a single outpatient visit. Forty-four of 1128 images (3.9%) could not be read by the algorithm, and were categorized as inconclusive. In four subjects, neither eye provided an acceptable image: these four subjects were excluded from the analysis. This left 560 subjects for analysis (1084 eyes). The algorithm correctly diagnosed 531 of 560 cases. The sensitivity, specificity, and positive and negative predictive values were 91%, 97%, 94%, and 95% respectively. The Bosch DR Algorithm shows favorable sensitivity and specificity in diagnosing DR from non-mydriatic images, and can greatly simplify screening for DR. This also has major implications for telemedicine in the use of screening for retinopathy in patients with diabetes mellitus.

Screening Intervals for Diabetic Retinopathy and Implications for Care

PURPOSE OF REVIEW

The purpose of this study is to review the evidence that lower risk groups who could safely be screened less frequently for sight-threatening diabetic retinopathy (DR) than annually.

RECENT FINDINGS

Data have demonstrated that people with no DR in either eye are at a low risk of progression to sight-threatening DR over a 2-year period (event rate 4.8 per 1000 person years), irrespective of whether the screening method is one-field non-mydriatic or two-field mydriatic digital photography. Low risk has been defined as no retinopathy on two consecutive screening episodes or no retinopathy on one screening episode combined with risk factor data. The risk of an extension to 2 years is less than 5 per 1000 person years in a population with a national screening programme, and the general standard of diabetes care is relatively good, whether low risk is defined as no retinopathy on two consecutive screening episodes or no retinopathy on one screening episode combined with other risk factor data. The definition used in different populations is likely to depend on the availability of data.