Action on diabetic macular oedema: achieving optimal patient management in treating visual impairment due to diabetic eye disease

Health economics of virtual versus face-to-face glaucoma clinics: a time-driven activity-based costing study

BACKGROUND/AIMS

Staffing represents the most significant cost to the National Health Service, and ophthalmology is its largest outpatient specialty. Value-based healthcare (VBH) focuses on care processes. Innovative models include a shift towards 'virtual' glaucoma services. We used VBH costing methodology to quantify personnel costs of virtual and face-to-face (F2F) glaucoma clinics.

METHODS

Virtual and F2F clinics were process-mapped to produce step-by-step pathways of patients in each setting. Real-world timings were then audited, and time-driven activity-based costing was used to calculate the personnel cost-per-patient for both settings.

RESULTS

Data were captured from 24 consecutive virtual glaucoma patients and 42 consecutive patients across two F2F clinics. The capacity cost rates in £/min were £0.24 for technicians and £1.16 for consultants. The average time taken to acquire clinical data in the virtual pathway was 39 min per patient (95% CI 36 to 43, range 27-61) with 14 min (95% CI 13 to 14, range 12-20) for their remote consultant review. The estimated personnel costs associated with a single virtual glaucoma clinic visit totalled £25.60 (95% CI £23.72 to £33.52). The average time taken to be seen in the F2F clinic was 50 min (95% CI 42 to 59 min, range 12-123 min) with a personnel cost of £31.08 (95% CI £19.70-£42.43).

CONCLUSION

Staff costs associated with visits to the consultant-delivered virtual and F2F glaucoma clinics were similar (p value=0.14), supporting virtual clinics to provide service capacity. The main limitations were that our study involved a single site, small sample size and did not consider the severity of glaucoma.

An eye on equity: faricimab-driven health equity improvements in diabetic macular oedema using a distributional cost-effectiveness analysis from a UK societal perspective

BACKGROUND/OBJECTIVES

Diabetic macular oedema (DMO) is a leading cause of blindness in developed countries, with significant disease burden associated with socio-economic deprivation. Distributional cost-effectiveness analysis (DCEA) allows evaluation of health equity impacts of interventions, estimation of how health outcomes and costs are distributed in the population, and assessments of potential trade-offs between health maximisation and equity. We conducted an aggregate DCEA to determine the equity impact of faricimab.

METHODS

Data on health outcomes and costs were derived from a cost-effectiveness model of faricimab compared with ranibizumab, aflibercept and off-label bevacizumab using a societal perspective in the base case and a healthcare payer perspective in scenario analysis. Health gains and health opportunity costs were distributed across socio-economic subgroups. Health and equity impacts, measured using the Atkinson inequality index, were assessed visually on an equity-efficiency impact plane and combined into a measure of societal welfare.

RESULTS

At an opportunity cost threshold of £20,000/quality-adjusted life year (QALY), faricimab displayed an increase in net health benefits against all comparators and was found to improve equity. The equity impact increased the greater the concerns for reducing health inequalities over maximising population health. Using a healthcare payer perspective, faricimab was equity improving in most scenarios.

CONCLUSIONS

Long-acting therapies with fewer injections, such as faricimab, may reduce costs, improve health outcomes and increase health equity. Extended economic evaluation frameworks capturing additional value elements, such as DCEA, enable a more comprehensive valuation of interventions, which is of relevance to decision-makers, healthcare professionals and patients.

Associated factors of diabetic retinopathy in type 1 and 2 diabetes in Limpopo province in South Africa

Background

Diabetic retinopathy (DR) is the major cause of vision impairment or blindness in individuals who have diabetes. It has accounted for 2.6% of all cases of blindness, and 1.9% of all cases of vision impairments globally. There is a lack of data on the prevalence of diabetic retinopathy and its associated factors amongst diabetic rural populations. Hence, the current study aimed to determine factors associated with diabetic retinopathy (DR) among diabetes mellitus (DM) patients undergoing diabetic therapy.

Methods

The study was cross-sectional in design and the participants were selected using convenient sampling. STATA version 15 software was used for data analysis. Chi-square was used to compare proportions. Logistic regression was used to determine the relationship between DR and associated risk factors.

Results

The prevalence of DR was 35.3%, of which 32% were mild and 3.4% were moderate non-proliferative DR (NPDR). Females were more unemployed than males (32.1% versus 16.8%, p=0.0058). Males were found to drink alcohol (21.8% versus 1.9%, p<0.001) and smoke cigarettes (4% versus 0.3%, p=0.0034) more than females. Being aged ≥ 55 years (OR: 2.7, 95% CI: 1.6-4.4), with matric qualification (OR: 0.6; 95% CI: 0.4-1.0); employed (OR: 1.4, 95% CI: 1.2-1.6); having high systolic blood pressure (OR=1.4, 95%CI=1.1-1.7) were the independent determinants of DR.

Conclusions

The prevalence of diabetic retinopathy was 34%. DR was determined by high systolic blood pressure, old age, and employment. Although not statistically significant, gender, hyperglycemic state, poor glycemic control, smoking, and increased body mass index (BMI) were associated with increased risk of developing DR.

Multi-Scale-Denoising Residual Convolutional Network for Retinal Disease Classification Using OCT

Macular pathologies can cause significant vision loss. Optical coherence tomography (OCT) images of the retina can assist ophthalmologists in diagnosing macular diseases. Traditional deep learning networks for retinal disease classification cannot extract discriminative features under strong noise conditions in OCT images. To address this issue, we propose a multi-scale-denoising residual convolutional network (MS-DRCN) for classifying retinal diseases. Specifically, the MS-DRCN includes a soft-denoising block (SDB), a multi-scale context block (MCB), and a feature fusion block (FFB). The SDB can determine the threshold for soft thresholding automatically, which removes speckle noise features efficiently. The MCB is designed to capture multi-scale context information and strengthen extracted features. The FFB is dedicated to integrating high-resolution and low-resolution features to precisely identify variable lesion areas. Our approach achieved classification accuracies of 96.4% and 96.5% on the OCT2017 and OCT-C4 public datasets, respectively, outperforming other classification methods. To evaluate the robustness of our method, we introduced Gaussian noise and speckle noise with varying PSNRs into the test set of the OCT2017 dataset. The results of our anti-noise experiments demonstrate that our approach exhibits superior robustness compared with other methods, yielding accuracy improvements ranging from 0.6% to 2.9% when compared with ResNet under various PSNR noise conditions.

INTEGRATING MACULAR OPTICAL COHERENCE TOMOGRAPHY WITH ULTRAWIDE-FIELD IMAGING IN A DIABETIC RETINOPATHY TELEMEDICINE PROGRAM USING A SINGLE DEVICE

PURPOSE

To determine the effect of combined macular spectral-domain optical coherence tomography (SD-OCT) and ultrawide field retinal imaging (UWFI) within a telemedicine program.

METHODS

Comparative cohort study of consecutive patients with both UWFI and SD-OCT. Ultrawide field retinal imaging and SD-OOCT were independently evaluated for diabetic macular edema (DME) and nondiabetic macular abnormality. Sensitivity and specificity were calculated with SD-OCT as the gold standard.

RESULTS

Four hundred twenty-two eyes from 211 diabetic patients were evaluated. Diabetic macular edema severity by UWFI was as follows: no DME 93.4%, noncenter involved DME (nonciDME) 5.1%, ciDME 0.7%, ungradable DME 0.7%. SD-OCT was ungradable in 0.5%. Macular abnormality was identified in 34 (8.1%) eyes by UWFI and in 44 (10.4%) eyes by SD-OCT. Diabetic macular edema represented only 38.6% of referable macular abnormality identified by SD-OCT imaging. Sensitivity/specificity of UWFI compared with SD-OCT was 59%/96% for DME and 33%/99% for ciDME. Sensitivity/specificity of UWFI compared with SDOCT was 3%/98% for epiretinal membrane.

CONCLUSION

Addition of SD-OCT increased the identification of macular abnormality by 29.4%. More than 58.3% of the eyes believed to have any DME on UWF imaging alone were false-positives by SD-OCT. The integration of SD-OCT with UWFI markedly increased detection and reduced false-positive assessments of DME and macular abnormality in a teleophthalmology program.

Development and validation of a risk prediction model for visual impairment in older adults

Objectives

This study aimed to determine the risk factors that affect visual impairment in older adults for developing and evaluating a visual impairment risk prediction model.

Methods

In this hospital-based unmatched case-control design study, we enrolled 586 participants (411 in the training set and 175 in the internal test set) from the ophthalmology clinic and physical examination center of a teaching hospital in Liaoning Province, China, from June to December 2020. Visual impairment was defined as best-corrected visual acuity <6/18 (The WHO definition). Possible influencing factors of visual impairment were assessed, including demographic factors, socioeconomic factors, disease and medication factors, and lifestyle. A visual impairment risk prediction model was developed using binary logistic regression analysis. The area under the ROC curve (AUC) was used to evaluate the effectiveness of the proposed prediction model.

Results

Six independent influencing factors of visual impairment in older adults were identified: age, systolic blood pressure, physical activity scores, diabetes, self-reported ocular disease history, and education level. A visual impairment risk prediction model for older adults was developed, showing powerful predictive ability in the training set and internal test set with AUCs of 0.87 (95%CI 0.83-0.90) and 0.81 (95%CI 0.74-0.88), respectively.

Conclusions

The risk prediction model for visual impairment in older adults had high predictive power. Identifying older adults at risk for developing visual impairment can help healthcare workers to adopt appropriate targeted programs for early education and intervention to prevent or delay visual impairment and prevent injuries due to visual impairment in older adults.

Subthreshold Micropulse Laser for Diabetic Macular Edema: A Review

Diabetic macular edema (DME) is one of the main causes of visual impairment in patients of working age. DME occurs in 4% of patients at all stages of diabetic retinopathy. Using a subthreshold micropulse laser is an alternative or adjuvant treatment of DME. Micropulse technology demonstrates a high safety profile by selectively targeting the retinal pigment epithelium. There are no standardized protocols for micropulse treatment, however, a 577 nm laser application over the entire macula using a 200 μm retinal spot, 200 ms pulse duration, 400 mW power, and 5% duty cycle is a cost-effective, noninvasive, and safe therapy in mild and moderate macular edemas with retinal thickness below 400 μm. Micropulse lasers, as an addition to the current gold-standard treatment for DME, i.e., anti-vascular endothelial growth factor (anti-VEGF), stabilize the anatomic and functional retinal parameters 3 months after the procedure and reduce the number of required injections per year. This paper discusses the published literature on the safety and application of subthreshold micropulse lasers in DME and compares them with intravitreal anti-VEGF or steroid therapies and conventional grid laser photocoagulation. Only English peer-reviewed articles reporting research within the years 2010-2022 were included.

Epidemiology of Ocular Manifestations in Autoimmune Disease

The global prevalence of autoimmune diseases is increasing. As a result, ocular complications, ranging from minor symptoms to sight-threatening scenarios, associated with autoimmune diseases have also risen. These ocular manifestations can result from the disease itself or treatments used to combat the primary autoimmune disease. This review provides detailed insights into the epidemiological factors affecting the increasing prevalence of ocular complications associated with several autoimmune disorders.

Comparing Objective Perimetry, Matrix Perimetry, and Regional Retinal Thickness in Mild Diabetic Macular Edema

Purpose

To compare per-region macular sensitivity and delay from objective perimetry with Matrix perimetry and retinal thickness in mild diabetic macular edema (DMO).

Methods

Thirty-three patients with type 2 diabetes (T2D) aged 59.2 ± 10.5 years participated in a longitudinal study. Macular thickness, sensitivities and delays from the objectiveFIELD Analyzer (OFA), and Matrix perimeter sensitivities were mapped onto a common spatial layout to compute per-region correlations between structure/function measures. A generalized linear mixed-effects logistic regression model determined which variables contributed to clinical diagnosis of DMO.

Results

For OFA, the mean sensitivity differences compared with normal in patients with T2D were negative and the mean delay differences positive, indicating lowered sensitivities and prolonged delays, both increasing with diabetes duration. Shorter diabetes duration could produce either localized peripheral hypersensitivities or shorter delays. Functional change could occur when retinal thickness was stable. Peripheral macular thickness correlated with central and peripheral OFA sensitivity and delay, all P < 0.0012 in DMO and a median of P = 0.001 without DMO; this was not true for Matrix sensitivities. The logistic model determined that peripheral thickness, OFA sensitivity (P = 0.043), and time in the study (P = 0.001) contribute independently to the odds of DMO versus no DMO.

Conclusions

Mean sensitivities decreased and mean delays increased with duration of diabetes. Peripheral macular thickness correlated significantly with central and peripheral macular OFA sensitivity and delay. Peripheral macular thickness and functional measures may provide sensitive prognostic data.

Translational Relevance

Functional loss can precede structural change in DMO, so including such functional assessment for deciding on treatment may be beneficial.

Diabetic retinopathy and diabetic macular oedema pathways and management: UK Consensus Working Group

The management of diabetic retinopathy (DR) has evolved considerably over the past decade, with the availability of new technologies (diagnostic and therapeutic). As such, the existing Royal College of Ophthalmologists DR Guidelines (2013) are outdated, and to the best of our knowledge are not under revision at present. Furthermore, there are no other UK guidelines covering all available treatments, and there seems to be significant variation around the UK in the management of diabetic macular oedema (DMO). This manuscript provides a summary of reviews the pathogenesis of DR and DMO, including role of vascular endothelial growth factor (VEGF) and non-VEGF cytokines, clinical grading/classification of DMO vis a vis current terminology (of centre-involving [CI-DMO], or non-centre involving [nCI-DMO], systemic risks and their management). The excellent UK DR Screening (DRS) service has continued to evolve and remains world-leading. However, challenges remain, as there are significant variations in equipment used, and reproducible standards of DMO screening nationally. The interphase between DRS and the hospital eye service can only be strengthened with further improvements. The role of modern technology including optical coherence tomography (OCT) and wide-field imaging, and working practices including virtual clinics and their potential in increasing clinic capacity and improving patient experiences and outcomes are discussed. Similarly, potential roles of home monitoring in diabetic eyes in the future are explored. The role of pharmacological (intravitreal injections [IVT] of anti-VEGFs and steroids) and laser therapies are summarised. Generally, IVT anti-VEGF are offered as first line pharmacologic therapy. As requirements of diabetic patients in particular patient groups may vary, including pregnant women, children, and persons with learning difficulties, it is important that DR management is personalised in such particular patient groups. First choice therapy needs to be individualised in these cases and may be intravitreal steroids rather than the standard choice of anti-VEGF agents. Some of these, but not all, are discussed in this document.

Adherence of patients with diabetic macular oedema to intravitreal injections: A systematic review

The purpose of this study was to review adherence rates to intravitreal injections in the treatment of diabetic macula oedema and to identify factors associated with adherence. A systematic search of Embase, Medline, PsycINFO and CINAHL was conducted up to May 2020. Two authors independently screened, selected and appraised the studies. Seven articles on anti-VEGF treatment were found to meet the inclusion criteria. No studies were found on intravitreal corticosteroids or dexamethasone implants. Attendance rates varied between studies from 35% to 85%. The rate of missed or delayed attendance ranged from 14% to 51%, whereas 25% of patients were lost to follow-up at 12 months. Non-adherence was found to be multifactorial and included patient related reasons, demographic characteristics and clinical factors. Enablers to adherence included patient understanding of the disease and treatment. Further research in this area is warranted in order to better understand adherence in these patients and to improve patient outcomes.

Fundamental principles of an effective diabetic retinopathy screening program

BACKGROUND

Diabetic retinopathy (DR) is the leading cause of blindness among working-age adults worldwide. Early detection and treatment are necessary to forestall vision loss from DR.

METHODS

A working group of ophthalmic and diabetes experts was established to develop a consensus on the key principles of an effective DR screening program. Recommendations are based on analysis of a structured literature review.

RESULTS

The recommendations for implementing an effective DR screening program are: (1) Examination methods must be suitable for the screening region, and DR classification/grading systems must be systematic and uniformly applied. Two-field retinal imaging is sufficient for DR screening and is preferable to seven-field imaging, and referable DR should be well defined and reliably identifiable by qualified screening staff; (2) in many countries/regions, screening can and should take place outside the ophthalmology clinic; (3) screening staff should be accredited and show evidence of ongoing training; (4) screening programs should adhere to relevant national quality assurance standards; (5) studies that use uniform definitions of risk to determine optimum risk-based screening intervals are required; (6) technology infrastructure should be in place to ensure that high-quality images can be stored securely to protect patient information; (7) although screening for diabetic macular edema (DME) in conjunction with DR evaluations may have merit, there is currently insufficient evidence to support implementation of programs solely for DME screening.

CONCLUSION

Use of these recommendations may yield more effective DR screening programs that reduce the risk of vision loss worldwide.

Optical Quality and Intraocular Scattering in the Diabetic Eye without Diabetic Retinopathy

SIGNIFICANCE

This study suggests that despite having comparable best-corrected visual acuity and normal fundus appearance, objective measurements of optical quality showed that patients with diabetes but without overt retinopathy may have impaired visual function. Screening using the Optical Quality Analysis System might help identify those patients.

PURPOSE

Visual impairments are common in diabetes, but the status of the problem is unclear before the development of diabetic retinopathy. The aim of this pilot study was to investigate the optical quality and intraocular scattering in the diabetic eye without diabetic retinopathy.

METHODS

Twenty-seven patients with diabetes without diabetic retinopathy were enrolled. Twenty-seven age- and sex-matched healthy volunteers served as a control group. Optical quality parameters included modulation transfer function cutoff frequency, Strehl (two-dimensional) ratio, and Optical Quality Analysis System values at 100, 20, and 9 contrast levels. The objective scatter index was assessed using the Optical Quality Analysis System. Correlations were analyzed between the modulation transfer function cutoff, Strehl ratio, objective scatter index, and Optical Quality Analysis System value, and the age of the patient and the duration of diabetes mellitus.

RESULTS

The diabetic group exhibited lower modulation transfer function cutoff, Strehl ratio, and Optical Quality Analysis System values at 100, 20, and 9% contrast levels and higher objective scatter index than did the controls (all, P < .01). There were no associations between the optical quality parameters and age or the duration of diabetes mellitus in the diabetic participants (all, P > .05). Moderate associations were found between all parameters obtained from the Optical Quality Analysis System and age in the control group (all, P < .01).

CONCLUSIONS

This pilot study suggests that optical quality was reduced, and intraocular scattering increased in the diabetic eye without diabetic retinopathy compared with controls.

Impact of Intravitreal Ranibizumab Therapy on Vision Outcomes in Diabetic Macular Edema Patients: A Meta-Analysis

PURPOSE

Evaluation of the impact of the injection frequency of ranibizumab on best-corrected visual acuity (BCVA) outcomes in patients with diabetic macular edema (DME).

METHODS

A meta-analysis of randomized controlled trials (RCTs) and real-world studies was performed to quantify the effect of ranibizumab treatment on BCVA and central foveal thickness (CFT) in DME as well as the relationship between the number of injections and the change in BCVA/CFT.

RESULTS

All combined sources (29 RCTs and 11 real-life studies) showed a significant increase in BCVA from baseline following anti-vascular endothelial growth factor (VEGF) treatment (8.2, 9.4, and 10.3 ETDRS letters gained after 12, 24, and 36 months of ranibizumab treatment, respectively). The largest changes in BCVA were observed in RCTs and the smallest in real-life studies at 12 months. A significant relationship was found between the number of injections and change in BCVA at 12 months.

CONCLUSIONS

Inferior vision outcomes were observed in clinical practice compared with RCTs and might be partly attributable to administration of fewer anti-VEGF injections. Physicians should be aware that early and appropriate anti-VEGF treatment regimens are necessary to obtain the results reported in RCTs and help prevent irreversible vision loss in DME patients.

The War on Diabetic Retinopathy: Where Are We Now?

Diabetic retinopathy (DR), a major cause of blindness in working-age adults, is emerging as a major public health issue worldwide, in particular in low- and middle-income countries (LMIC). Traditionally, the management of DR has been on tertiary-level treatment (eg, laser, anti-VEGF injections and surgery) in specialized settings by highly trained ophthalmologists on individual patients. To win the war on DR, a paradigm shift in strategic focus and resources must be made from such tertiary treatment toward primary and secondary prevention, which are broader, more impactful, and cost-effective for the larger population. These include improving education and awareness of risk of DR among people initially diagnosed with diabetes, promoting behavioral modifications such as physical activity and medication adherence for improving glycemic and blood pressure control, setting up systematic screening programs for DR to detect the onset or progression of the disease, and implementing cost-effective, evidence-based policies and guidelines for managing DR. Additionally, there is a need to leverage on novel technology including the application of digital big data to predict people at risk of diabetes and DR, the use of wearable devices and smart phone apps, behavioral techniques including social media for self-management of diabetes, and telemedicine-based DR screening incorporating artificial intelligence (AI) to broaden access to screening in all settings. To turn the tide on the war on DR, we must reframe DR not only as a specific condition that can be managed by ophthalmologists, but fundamentally, as a preventable condition by shifting the weight of strategies from tertiary to secondary and primary battlegrounds.

Modeling a Telemedicine Screening Program for Diabetic Retinopathy in Iran and Implementing a Pilot Project in Tehran Suburb

PURPOSE

To model a community-based telescreening program for diabetic retinopathy (DR) in Iran and to implement a pilot project at the Iranian Diabetes Society (IDS) branch in a Tehran suburb.

METHODS

In this mixed model study, a web application called the "Iranian Retinopathy Teleophthalmology Screening (IRTOS)" was launched. The educational course for DR screening was established for general practitioners (GPs). Registered patients in IDS branch were recalled for fundus photography; images were transferred to the reading center via IRTOS to be graded by GPs, and patients were informed about the results via mobile messaging. All images were independently reviewed by a retina specialist as the gold standard. Patients who required further assessment were referred to an eye hospital.

RESULTS

Overall, 604 subjects with diabetes were screened; of these, 50% required referral. The sensitivity and specificity for diagnosis of any stage of DR by trained GPs were 82.8% and 86.2%, respectively, in comparison to the gold standard. The corresponding values for detecting any stage of diabetic macular edema (DME) were 63.5% and 96.6%, respectively.

CONCLUSIONS

Telescreening was an effective method for detecting DR in a Tehran suburb. This screening model demonstrated its capacity for promoting diabetic eye care services at the national level. However, the sensitivity for detecting DME needs to be improved by modifying the referral pathway and promoting the skill of GPs.

Therapeutic targeting of angiogenesis molecular pathways in angiogenesis-dependent diseases

Angiogenesis is a critical step in the progression of almost all human malignancies and some other life-threatening diseases. Anti-angiogenic therapy is a novel and effective approach for treatment of angiogenesis-dependent diseases such as cancer, diabetic retinopathy, and age-related macular degeneration. In this article, we will review the main strategies developed for anti-angiogenic therapies beside their clinical applications, the major challenges, and the latest advances in the development of anti-angiogenesis-based targeted therapies.

Evaluation of the self-eye examination method for health promotion

OBJECTIVE

To evaluate the self-eye examination practice as a tool to promote the ocular self-evaluation.

METHOD

Quasi-experimental study developed in a university of Piauí with sample of 324 students between January and May 2014. A team of thirteen researchers made observations during the self-examination followed by an ocular screening.

RESULTS

There was no agreement on the hypothesis of defense that the ocular exam could help to observe the eyes health, p-value>0.3. However, the exam was considered as easy to accomplish (99.7%) and that not only the physician can perform the eye exam (99.4%). The awareness about eye care is identified as the main purpose of this booklet (97.6%), (χ2= 186.01; p=0.001). The results highlight the booklet can be used in the teaching process of self-eye examination (84.6%). Although the defense that its fulfilment can replace the consultation with the ophthalmologist (23.8%%) cannot be accepted (χ2= 46.34), the self-exam must be done routinely (82.4%).

CONCLUSION

The results prove that the learning through virtual booklet is possible and supports self-care with the eyes by performing the self-exam.