American Society of Retina Specialists Clinical Practice Guidelines on the Management of Nonproliferative and Proliferative Diabetic Retinopathy without Diabetic Macular Edema

Expanded Field OCT Angiography Biomarkers for Predicting Clinically Significant Outcomes in Non-Proliferative Diabetic Retinopathy

PURPOSE

To evaluate the utility of extended field swept-source Optical Coherence Tomography Angiography (SS-OCTA) imaging biomarkers in predicting the occurrence of clinically significant outcomes in eyes with Non-Proliferative Diabetic Retinopathy (NPDR).

DESIGN

Retrospective clinical case-control study.

METHODS

Single-center clinical study. Eighty-eight eyes with NPDR from 57 participants (median age: 64.0 years; mean duration of diabetes: 15.8 years) with at least 2 consecutive SS-OCTA scans over a follow-up period of at least 6 months were included. The presence of intraretinal microvascular abnormalities (IRMAs) at baseline and the stability of IRMAs during follow-up period on 12 × 12-mm angiograms were evaluated. Baseline nonperfusion ischemia index (ISI) and other SS-OCTA metrics were calculated on FIJI and ARI Network. Significant clinical outcomes were defined as occurrence of one or more of the following events at the last available clinical visit:1. significant DR progression (2-step DR progression or progression to proliferative DR (PDR)); 2) development of new center-involving diabetic macular edema (CI-DME); and 3) initiation of treatment with PRP or anti-VEGF injections during the follow-up period. Mixed-effects Cox regression models was used to explore these outcomes.

RESULTS

Following a clinical follow-up period lasting 25.1 ± 10.8 months, we observed significant clinical outcomes in 17 eyes (19.3%). Among these, 7 eyes (8.0%) experienced significant progression and 4 eyes (4.5%) developed CI-DME. Anti-VEGF injections were initiated in 15 eyes (17.0%), while PRP was initiated in 2 eyes (2.3%). Upon adjusting for age, the duration of DM, and prior Anti-VEGF treatments, our analysis revealed that non-stable IRMAs during the follow-up periods and a higher ischemia index at baseline were significantly associated with the occurrence of significant clinical outcomes with HRs of 3.88 (95% CI: 1.56-9.64; p = .004) and 1.05 (95% CI: 1.02-1.09; p = .004), respectively.

CONCLUSIONS

In conclusion, NPDR eyes with non-stable IRMAs over time and more ischemia at baseline are in higher risk of developing significant clinical outcomes. Our findings suggest that expanded field SS-OCTA may offer additional prognostic benefits for clinical DR staging and predicting high-risk patients.

Inhibition of viability of human retinal microvascular endothelial cells by vialinin A under high glucose condition

AIM

To investigate the effects of vialinin A on viability of human retinal endothelial cells (HRECs) under high glucose condition and its potential mechanism.

METHODS

The HRECs were divided into four groups: normal glucose control group (NG, 5 mmol/L D-glucose), high glucose group (HG, 30 mmol/L D-glucose), HG+1 µmol/L vialinin A group, and HG+5 µmol/L vialinin A group. The cell viabilities were measured with cell counting kit-8 (CCK-8) assay for proliferation, with scratch assay for migration, and tube formation, for evaluation of the impact of vialinin A on cellular behaviour. Real-time PCR and Western blotting were used to determine the expression level of vascular endothelial growth factor (VEGF).

RESULTS

The proliferative capacity and migration of HRECs was reduced by 5 µmol/L vialinin A in high glucose environment (both P<0.05). Vialinin A also inhibited high-glucose-induced tube formation of HRECs. The expression level of VEGF and PI3K in HRECs was also significantly decreased by vialinin A (P<0.05).

CONCLUSION

Vialinin A inhibits the cell viability of HRECs. It may serve as a potential target for anti-angiogenic therapy.

The Genetic Variants of Long Noncoding RNA MEG3 and Its Association to the Clinical Features of Diabetic Retinopathy

PURPOSE

This study aimed to investigate the potential correlation between the single-nucleotide polymorphism (SNP) of maternally expressed gene 3 (MEG3) and the clinical manifestations of diabetic retinopathy (DR).

METHODS

Five loci of MEG3 SNPs including rs4081134 (G/A), rs10144253 (T/C), rs7158663 (G/A), rs3087918 (T/G) and rs11160608 (A/C) were genotyped by TaqMan allelic discrimination in 457 non-DR patients and 280 DR individuals.

RESULTS

The distribution frequency of MEG3 SNP rs7158663 GA (AOR: 0.683, 95% CI: 0.478-0.975, p = 0.036) and MEG3 SNP rs7158663 GA + AA (AOR: 0.686, 95% CI: 0.487-0.968, p = 0.032) were significantly lower in the DR group. And the MEG3 SNP rs7158663 GA + AA (AOR: 0.610, 95% CI: 0.377-0.985, p = 0.043) demonstrated a significantly lower distribution frequency in the male DR group. Besides, the DR patients with MEG3 SNP rs7158663 GA + AA genotype showed a significantly lower HbA1c level than the DR patients with MEG3 SNP rs7158663 GG genotype (7.29 ± 1.23 versus 7.74 ± 1.49, p = 0.013). Moreover, in the analysis using data from gene expression data series database, a higher MEG3 level was significantly correlated to a lower miR-182 level in the database (p = 0.0114).

CONCLUSIONS

In this study, the distribution frequency of MEG3 SNP rs7158663 GA + AA genotype was lower in DR, while the DR would develop under lower HbA1c level in DM patients with this MEG3 SNP variant.

Wide-Field Optical Coherence Tomography in Patients with Diabetic Macular Edema

Background: The goal of the study was to analyze variations in central, perifoveal, and peripheral retinal thickness (RT) and choroidal thickness (CT) in patients with diabetic macular edema (DME) measured with ultra-wide-field optical coherence tomography (UWF-OCT). Additionally, correlations between RT and CT in the central, perifoveal, and peripheral sectors and the presence of selected systemic factors were evaluated. Methods: A total of 74 consecutive adult diabetic patients with DME and 75 healthy controls were included. Study participants were divided into three groups: DME patients without panretinal photocoagulation (PRP; 84 eyes), DME patients after PRP (56 eyes), and healthy controls (125 eyes). RT and CT were analyzed in three zones: a central circle of 3 mm diameter (central), a ring contained between a centered 9 mm circle and the central 3 mm circle (perifoveal), and a second, more peripheral ring between centered 18 mm and 9 mm circles (peripheral). Additionally, DME subgroups were analyzed according to the correlation of RT and CT with age, axial length, best corrected visual acuity (BCVA), diabetes duration, insulin therapy duration, body mass index (BMI), glycosylated hemoglobin (HbA1c) values, intravitreal injection (IVI) count, and the advancement of retinopathy assessed by the simplified diabetic retinopathy severity scale (DRSS). Results: The increase in RT in the far peripheral sectors in DME patients was not significant. The increases in central and perifoveal RT and lower values of CT in PRP-naive DME patients were strongly associated with poorer BCVA. Patients with DME after PRP presented with BCVA improvements significantly related to the number of IVIs. The amount of DME and RT in peripheral sectors were both independent of systemic factors such as BMI, duration of diabetes, duration of insulin intake, retinopathy severity, and HbA1c levels. Conclusions: Peripheral retinal sectors in DME patients are less affected in terms of increase in their thickness compared to central ones. Functional and morphological associations of DME with UWF-OCT testing refer to central and perifoveal sectors.

Impact of anti-VEGF treatment on development of proliferative diabetic retinopathy in routine clinical practice

BACKGROUND

This study evaluated impact of anti-vascular endothelial growth factor (VEGF) treatment on proliferative diabetic retinopathy (PDR) development among patients with non-proliferative diabetic retinopathy (NPDR) in US real-world clinical practice.

METHODS

This was a retrospective analysis of electronic medical records (Vestrum Health; January 2013 to June 2019) of eyes with baseline NPDR, without DME, and naïve to anti-VEGF treatment at index DR diagnosis. Eyes that received anti-VEGF and/or laser treatment over the course of study before development of PDR constituted the treated cohort while the remaining including those treated with laser constituted the anti-VEGF naïve cohort. Survival analysis via Kaplan-Meier method evaluated time to DME and PDR development by baseline NPDR severity, with anti-VEGF treatment as censoring variable. Baseline factors affecting PDR development were analyzed using Cox multivariable regression, censoring for anti-VEGF treatment.

RESULTS

Among anti-VEGF-naive eyes, cumulative incidence of DME in eyes with mild (n = 70,050), moderate (n = 39,116), and severe NPDR (n = 10,692) at baseline was 27.1%, 51.2%, and 60.6%. Multivariable regression analysis identified baseline NPDR severity as the most significant predictor of PDR development over 48 months (hazard ratio [HR] [95% confidence interval {CI}] of 2.69 (2.65-2.72) for moderate vs mild NPDR and 6.51 (6.47-6.55) for severe vs mild NPDR). Cumulative incidence (95% CI) of PDR was 7.9% (7.4%-8.3%), 20.9%, (20.0%-21.7%) and 46.8% (44.4%-49.2%) over 48 months in eyes with mild, moderate, and severe NPDR at baseline, respectively. Among treated eyes with baseline severe NPDR, cumulative incidence of PDR at 48 months was 50.1% in eyes treated with laser (n = 546; HR [95% CI] vs no treatment: 0.8 [0.7-1.0]), 27.4% in eyes treated with anti-VEGF (n = 923; HR [95% CI]: 0.4 [0.4-0.5]), and 25.6% in eyes treated with anti-VEGF plus laser (n = 293; HR [95% CI]: 0.5 [0.4-0.7]) compared with 49.9% in eyes with no treatment (n = 8930).

CONCLUSIONS

DME and PDR development rates increased with increasing baseline NPDR severity. Approximately half of anti-VEGF‒naive eyes with severe NPDR progressed to PDR within 4 years in US clinical practice. The progression rate from severe NPDR to PDR was approximately halved with anti-VEGF versus no treatment.

Diabetic Disease of the Eye in Canada: Consensus Statements from a Retina Specialist Working Group

Despite advances in systemic care, diabetic disease of the eye (DDE) remains the leading cause of blindness worldwide. There is a critical gap of up-to-date, evidence-based guidance for ophthalmologists in Canada that includes evidence from recent randomized controlled trials. Previous guidance has not always given special consideration to applying treatments and managing DDE in the context of the healthcare system. This consensus statement aims to assist practitioners in the field by providing a spectrum of acceptable opinions on DDE treatment and management from recognized experts in the field. In compiling evidence and generating consensus, a working group of retinal specialists in Canada addressed clinical questions surrounding the four themes of disease, patient, management, and collaboration. The working group reviewed literature representing the highest level of evidence on DDE and shared their opinions on topics surrounding the epidemiology and pathophysiology of diabetic retinopathy and diabetic macular edema; diagnosis and monitoring; considerations around diabetes medication use; strategic considerations for management given systemic comorbidities, ocular comorbidities, and pregnancy; treatment goals and modalities for diabetic macular edema, non-proliferative and proliferative diabetic retinopathy, and retinal detachment; and interdisciplinary collaboration. Ultimately, this work highlighted that the retinal examination in DDE not only informs the treating ophthalmologist but can serve as a global index for disease progression across many tissues of the body. It highlighted further that DDE can be treated regardless of diabetic control, that a systemic approach to patient care will result in the best health outcomes, and prevention of visual complications requires a multidisciplinary management approach. Ophthalmologists must tailor their clinical approach to the needs and circumstances of individual patients and work within the realities of their healthcare setting.

Intravitreal aflibercept 8 mg in diabetic macular oedema (PHOTON): 48-week results from a randomised, double-masked, non-inferiority, phase 2/3 trial

BACKGROUND

A high-dose formulation of intravitreal aflibercept (8 mg) could improve treatment outcomes in diabetic macular oedema (DMO) by requiring fewer injections than the standard comparator, aflibercept 2 mg. We report efficacy and safety results of aflibercept 8 mg versus 2 mg in patients with DMO.

METHODS

PHOTON was a randomised, double-masked, non-inferiority, phase 2/3 trial performed at 138 hospitals and specialty retina clinics in seven countries. Eligible patients were adults aged 18 years or older with type 1 or 2 diabetes and centre-involved DMO. Patients were randomly assigned (1:2:1) to intravitreal aflibercept 2 mg every 8 weeks (2q8), aflibercept 8 mg every 12 weeks (8q12), or aflibercept 8 mg every 16 weeks (8q16), following initial monthly dosing. From week 16, dosing intervals for the aflibercept 8 mg groups were shortened if patients met prespecified dose regimen modification criteria denoting disease activity. The primary endpoint was change from baseline in best-corrected visual acuity (BCVA) at week 48 (non-inferiority margin of 4 letters). Efficacy and safety analyses included all randomly assigned patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov (NCT04429503).

FINDINGS

Between June 29, 2020, and June 28, 2021, 970 patients were screened for eligibility. After exclusions, 660 patients were enrolled and randomly assigned to receive aflibercept 8q12 (n=329), 8q16 (n=164), or 2q8 (n=167); two patients were randomly assigned in error and did not receive treatment. 658 (99·7%) patients were treated and included in the full analysis set and safety analysis set (8q12 n=328, 8q16 n=163, and 2q8 n=167). Mean patient age was 62·3 years (SD 10·4). 401 (61%) patients were male. 471 (72%) patients were White. Aflibercept 8q12 and 8q16 demonstrated non-inferior BCVA gains to aflibercept 2q8 (BCVA mean change from baseline 8·8 letters [SD 9·0] in the 8q12 group, 7·9 letters [8·4] in the 8q16 group, and 9·2 letters [9·0] in the 2q8 group). The difference in least squares means was -0·57 letters (95% CI -2·26 to 1·13, p value for non-inferiority <0·0001) between 8q12 and 2q8 and -1·44 letters (-3·27 to 0·39, p value for non-inferiority 0·0031) between aflibercept 8q16 and 2q8. Proportions of patients with ocular adverse events in the study eye were similar across groups (8q12 n=104 [32%], 8q16 n=48 [29%], and 2q8 n=46 [28%]).

INTERPRETATION

Aflibercept 8 mg demonstrated efficacy and safety with extended dosing intervals and could decrease treatment burden in patients with DMO.

FUNDING

Regeneron Pharmaceuticals and Bayer.

Efficacy and Safety of Brolucizumab for Diabetic Macular Edema: The KINGFISHER Randomized Clinical Trial

Importance

Despite the effectiveness of existing anti-vascular endothelial growth factor (VEGF) therapies, a need remains for further treatment options to improve response rates and/or reduce injection or monitoring frequency in patients with diabetic macular edema (DME).

Objective

To evaluate the efficacy and safety of brolucizumab vs aflibercept dosed every 4 weeks in participants with DME.

Design, Participants, and Setting

This 52-week, double-masked, phase 3 randomized clinical trial included treatment-naive adults and adults who had previously received anti-VEGF therapy. Data were collected from September 2019 to March 2020, and data were analyzed from April 2020 to February 2021.

Intervention

Brolucizumab, 6 mg, intravitreal injection every 4 weeks or aflibercept, 2 mg, intravitreal injection every 4 weeks.

Main Outcomes and Measures

Participants were randomized 2:1 to brolucizumab, 6 mg, or aflibercept, 2 mg. The primary end point was change from baseline in best-corrected visual acuity at week 52. Secondary end points were the proportion of participants with a 2-step improvement or greater from baseline in Diabetic Retinopathy Severity Scale score, the proportion of eyes with absence of both subretinal fluid and intraretinal fluid, change from baseline in central subfield thickness, and safety at week 52.

Results

A total of 517 participants were randomized to brolucizumab (n = 346) or aflibercept (n = 171); 299 (57.8%) were male, and the mean (SD) age was 60.7 (10.2) years. Brolucizumab was noninferior to aflibercept in best-corrected visual acuity (Early Treatment Diabetic Retinopathy Study letter score) change from baseline at week 52 (brolucizumab, 12.2-letter improvement; aflibercept, 11.0-letter improvement; difference, 1.1; 95% CI, -0.6 to 2.9; noninferiority margin, 4; P < .001). Brolucizumab was superior to aflibercept for the proportion of eyes without subretinal and intraretinal fluid (brolucizumab, 144 of 346 [41.6%]; aflibercept, 38 of 171 [22.2%]; difference, 20.0%; 95% CI, 12.5to 28.6; P < .001) and mean central subfield thickness change from baseline at week 52 (brolucizumab, -237.8 μm; aflibercept, -196.5 μm; difference, -41.4; 95% CI, -58.9 to -23.8; P < .001). Incidence of intraocular inflammation was 4.0% (14 of 346) in the brolucizumab arm and 2.9% (5 of 171) in the aflibercept arm, incidence of retinal vasculitis was 0.9% (3 of 346) and 0.6% (1 of 171), respectively, and incidence of retinal vascular occlusion was 0.3% (1 of 346) and 0.6% (1 of 171). One participant in the brolucizumab arm had retinal artery occlusion.

Conclusions and Relevance

In these study participants with DME, no clinically meaningful differences in visual outcomes were noted between the brolucizumab and aflibercept arms; some superior anatomic improvements were noted in the brolucizumab arm. No new safety concerns were identified.

Trial Registration

ClinicalTrials.gov Identifier: NCT03917472.

Panretinal photocoagulation plus intravitreal conbercept for diabetic retinopathy in real world: a retrospective study

BACKGROUND

To evaluate outcomes of panretinal photocoagulation (PRP) plus intravitreal conbercept (IVC) for diabetic retinopathy (DR) in real world and explore risk factors for patients with poor reactivity and presence of vision-threatening complications after combination treatment.

METHODS

Retrospective review of DR patients received PRP plus IVC over 6 months. The main outcome was improvement ≥ 2 steps in ETDRS diabetic retinopathy severity scale (DRSS) levels. Different strategies for eyes receiving IVC within or over 1 month after PRP were analyzed. For patients with DRSS improvement < 2 steps and presence of vision-threatening adverse events, a binary logistic regression method was used to select risk factors.

RESULTS

Sixty one eyes were involved in this study. After treated with combination therapy with a median number of 3 injections, 44% of eyes improved ≥ 2 steps in DRSS levels. A total of 14 eyes (23%) occurred vision-threatening adverse events. No significant difference was found in eyes receiving conbercept within or over 1 month after PRP. Duration of diabetes (OR 0.849, 95%CI 0.734-0.982, P = 0.027), GFR (OR 0.961, 95%CI 0.933-0.990, P = 0.010) and baseline DRSS levels (OR 3.290, 95%CI 1.483-7.295, P = 0.003) were independent risk factors for DRSS improvement < 2 steps after treatment. Occurrence of vision-threatening complications was only related to high DRSS levels (OR 3.668, 95%CI 1.710-7.868, P = 0.001).

CONCLUSIONS

The combination therapy was effective for most patients with DR in real world. Eyes received PRP combined with earlier or later conbercept was demonstrated no significant difference for outcomes. For patients with poor renal function, high DRSS levels or occurred DR at the early stage of diabetes, follow-up should be strengthened.

Quantitative Evaluation of Fundus Autofluorescence in Laser Photocoagulation Scars for Diabetic Retinopathy: Conventional vs. Short-Pulse Laser

Short-pulse laser is popular for its advantages like less pain. However, its effectiveness is still debated. The aim of this study was to compare fundus autofluorescence (FAF) luminosity changes of laser photocoagulation scars between the conventional laser (0.2 s) and the short-pulse laser (0.02 s) for diabetic retinopathy. Conventional and short-pulse laser photocoagulations were performed in six and seven eyes, respectively. FAF images were captured at 1, 3, 6, 12, and 18 months after the treatments. To evaluate FAF, individual gray-scale values of the laser scars adjacent to the retinal arcade vessels were recorded; then, the mean gray values of the scars were divided by the luminosity of arcade vein. The average luminosity ratio of laser scars at 1, 3, 6, 12, and 18 months were 1.51 ± 0.17, 1.26 ± 0.07, 1.21 ± 0.03, 0.95 ± 0.11, and 0.89 ± 0.05 with conventional laser and 1.91 ± 0.13, 1.50 ± 0.15, 1.26 ± 0.08, 1.18 ± 0.06, and 0.97 ± 0.04 with short-pulse laser, respectively. Findings suggest the short-pulse laser displayed delayed hypoautofluorescence progression. This implies potential postponement in post-irradiation atrophic changes, as well as metabolic amelioration delay in the ischemic retina, when compared to conventional laser treatment.

Analysis of retinal and choroidal characteristics in patients with early diabetic retinopathy using WSS-OCTA

Introduction

Diabetic retinopathy (DR) is one of the most common and destructive microvascular complications of DM, and has become a major cause of irreversible visual impairment. The purpose of this study was to evaluate the changes in fundus microcirculation in non-diabetic retinopathy (NDR) and mild non-proliferative diabetic retinopathy (NPDR) in patients with type 2 diabetic mellitus (T2DM) using widefield swept-source optical coherence tomography angiography (WSSOCTA), and to investigate the correlation with laboratory indices of T2DM.

Methods

Eighty nine, 58 and 28 eyes were included in the NDR, NPDR and Control groups, respectively, were enrolled in this study. The 12mm×12mm fundus images obtained by WSS-OCTA were divided into 9 regions (supratemporal, ST; temporal, T; inferotemporal, IT; superior, S; central macular area, C; inferior, I; supranasal, SN; nasal, N; inferonasal, IN) to evaluate changes in vessel density (VD) of the superficial capillary plexus (SCP), deep capillary plexus (DCP), choriocapillaris, and mid-large choroidal vessel (MLCV), as well as changes in inner retinal thickness (IRT), outer retinal thickness (ORT), and choroidal thickness (CT). Results: Compared with control group, MLCV VD (I, N, IN) was significantly decreased in NDR group, SCP VD (IT, C, I) and DCP VD (T, IT, I) were significantly decreased in NPDR group. In NPDR group, DCP VD (IT) was significantly decreased compared with that in NDR group. Compared with control group, CT (ST, T, IT, S, SN, IN) was significantly declined in NDR group, and IRT (ST, IT) and ORT (ST, N) were significantly increased in NPDR group. In NPDR group, IRT (ST) and ORT (T, S) were significantly increased compared with NDR group. Correlation analysis showed that age, body mass index, fasting blood glucose, fasting insulin, fasting C-peptide, and estimated glomerular filtration rate in T2DM patients were statistically correlated with retinal and choroidal thickness/VD.

Discussion

Structural and blood flow changes in the choroid occur before the onset of DR and precede changes in the retinal microcirculation, and MLCV thickness/VD is a more sensitive imaging biomarker for the clinical detection of DR. WSS-OCTA enables large-scale non-invasive visual screening and follow-up of the retinal and choroidal vasculature in DR patients, providing a new strategy for the prevention and monitoring of DR in patients with T2DM.

Aflibercept for long-term treatment of diabetic macular edema and proliferative diabetic retinopathy: a meta-analysis

Purpose

This meta-analysis compared the long-term (12 months or 24 months) efficacy and safety of intravitreal aflibercept injection (IAI) for diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR).

Methods

We selected 16 randomized controlled trials (RCTs) performed after 2015 that had a minimum of 12 months and up to 24 months of treatment and conducted a meta-analysis with Review Manager version 5.3. Visual acuity (VA), central subfield thickness (CST) and adverse events were the outcomes selected for evaluation from the eligible studies.

Results

Based on 16 RCTs, we evaluated a total of 7125 patients. For PDR and severe DME with poor baseline vision, after a minimum of 12 months and up to 24 months of treatment, the aflibercept treatment group obtained better VA improvement than the focal/grid laser photocoagulation treatment group (MD=13.30; 95%CI: 13.01~13.58; P<0.001) or other treatments (ranibizumab, focal/grid laser photocoagulation, PRP, et al.) group (MD=1.10; 95%CI: 1.05~1.16; P<0.001). In addition, the aflibercept treatment group got higher CST reduction than the focal/grid laser photocoagulation treatment (MD=-33.76; 95%CI: -45.53 ~ -21.99; P<0.001) or other treatments (ranibizumab, focal/grid laser photocoagulation, et al.) group (MD=-33.76; 95%CI: -45.53 ~ -21.99; P<0.001). There was no significant difference in the overall incidence of ocular and non-ocular adverse events in each treatment group.

Conclusions

This meta-analysis showed that the advantages of IAI are obvious in the management of DME and PDR with poor baseline vision for long-term observation (a minimum of 12 months and up to 24 months) with both VA improvement and CST reduction. Applied IAI separately trended to be more effective than panretinal photocoagulation separately in VA improvement for PDR. More parameters should be required to assess functional and anatomic outcomes.

Diabetic Retinopathy among Patients with Prediabetes Attending the Outpatient Department of Ophthalmology in a Tertiary Eye Care Centre: A Descriptive Cross-sectional Study

INTRODUCTION

Diabetic retinopathy is a specific microvascular ocular complication associated with diabetes. However, retinopathy has also been reported in people with prediabetes. The study aimed to find out the prevalence of diabetic retinopathy among patients with prediabetes attending the outpatient Department of Ophthalmology in a tertiary eye care centre.

METHODS

A descriptive cross-sectional study was conducted among patients with prediabetes attending the outpatient Department of Ophthalmology in a tertiary eye care centre from 1 January 2022 and 30 April 2022. Ethical approval was obtained from the Ethical Review Board (Registration number: 594/2021 P). All patients had their eyes dilated and examined under the slit-lamp with a 90 D convex lens or indirect ophthalmoscopes with a 20 D lens to find retinopathy. All patients aged 40 to 79 years with intermediate hyperglycemia were included in the study. Convenience sampling was used. Point estimate and 95% Confidence Interval were calculated.

RESULTS

Among 141 patients with prediabetes, diabetic retinopathy was found in 8 (5.67%) (1.85-9.49, 95% Confidence Interval). Among which all patients 8 (5.67%) had mild non-proliferative diabetic retinopathy. Among patients with retinopathy, all 8 (5.67%) were obese, 3 (37.50%) were hypertensive, 5 (62.50%) patients had intermediate hyperglycemia for more than 6 months, and 2 (25%) had a family history of diabetes mellitus.

CONCLUSIONS

The prevalence of diabetic retinopathy in prediabetes patient was found to be higher than the other studies conducted in similar settings.

KEYWORDS

diabetic retinopathy; prediabetes; prevalence.

Eight years' experience in mobile teleophthalmology for diabetic retinopathy screening

Background

Screening for diabetic retinopathy in the community without compromising the routine work of ophthalmologists at hospitals is the essence of teleophthalmology. This study was aimed at investigating the efficacy of teleophthalmology practice for screening diabetic retinopathy from 2012 to 2020. It was also aimed at comparing the 2-year prevalence of camps organized by a district hospital in South India, as well as the footfall, reporting, follow-up, patient response, and diagnostic efficacy at these camps.

Methods

All patients with diabetes and unexplained vision deterioration attending the mobile camp units underwent non-dilated fundus photography. Patients underwent teleconsultation with the ophthalmologist at the district hospital, and those requiring intervention were called to the district hospital. Trends were studied for the number of patients reporting to the hospital. Patient satisfaction was recorded based on a questionnaire.

Results

A total of 682 camps were held over 8 years, and 30 230 patients were examined. Teleconsultation was done for 12 157 (40.21%) patients. Patients requiring further investigations, intervention for diabetic retinopathy, or further management of other ocular pathologies were urgently referred to the district hospital (n= 3293 [10.89%] of 30 230 examined patients). The severity and presence of clinically significant macular edema increased significantly with an increased duration of diabetes mellitus (P < 0.001). The percentage of teleconsultations showed an increasing trend over the years (P = 0.001). Similarly, considering trends of patients reporting to the hospital, the attrition rate decreased over the years (P < 0.05). A total of 10 974 of 12 157 (90.27%) patients who underwent teleophthalmic consultation were satisfied with the service.

Conclusions

Teleconsultations over the years showed an increasing trend, and the attrition rate decreased over the years. Teleophthalmology is achieving success in providing high-quality service, easy access to care, and in increasing patient satisfaction. Future studies on the role of teleophthalmology for other leading preventable causes of blindness seem possible and necessary.

The effectiveness of artificial intelligence-based automated grading and training system in education of manual detection of diabetic retinopathy

Background

The purpose of this study is to develop an artificial intelligence (AI)-based automated diabetic retinopathy (DR) grading and training system from a real-world diabetic dataset of China, and in particular, to investigate its effectiveness as a learning tool of DR manual grading for medical students.

Methods

We developed an automated DR grading and training system equipped with an AI-driven diagnosis algorithm to highlight highly prognostic related regions in the input image. Less experienced prospective physicians received pre- and post-training tests by the AI diagnosis platform. Then, changes in the diagnostic accuracy of the participants were evaluated.

Results

We randomly selected 8,063 cases diagnosed with DR and 7,925 with non-DR fundus images from type 2 diabetes patients. The automated DR grading system we developed achieved accuracy, sensitivity/specificity, and AUC values of 0.965, 0.965/0.966, and 0.980 for moderate or worse DR (95 percent CI: 0.976-0.984). When the graders received assistance from the output of the AI system, the metrics were enhanced in varying degrees. The automated DR grading system helped to improve the accuracy of human graders, i.e., junior residents and medical students, from 0.947 and 0.915 to 0.978 and 0.954, respectively.

Conclusion

The AI-based systemdemonstrated high diagnostic accuracy for the detection of DR on fundus images from real-world diabetics, and could be utilized as a training aid system for trainees lacking formal instruction on DR management.

Recent developments on computer aided systems for diagnosis of diabetic retinopathy: a review

Diabetes is a long-term condition in which the pancreas quits producing insulin or the body's insulin isn't utilised properly. One of the signs of diabetes is Diabetic Retinopathy. Diabetic retinopathy is the most prevalent type of diabetes, if remains unaddressed, diabetic retinopathy can affect all diabetics and become very serious, raising the chances of blindness. It is a chronic systemic condition that affects up to 80% of patients for more than ten years. Many researchers believe that if diabetes individuals are diagnosed early enough, they can be rescued from the condition in 90% of cases. Diabetes damages the capillaries, which are microscopic blood vessels in the retina. On images, blood vessel damage is usually noticeable. Therefore, in this study, several traditional, as well as deep learning-based approaches, are reviewed for the classification and detection of this particular diabetic-based eye disease known as diabetic retinopathy, and also the advantage of one approach over the other is also described. Along with the approaches, the dataset and the evaluation metrics useful for DR detection and classification are also discussed. The main finding of this study is to aware researchers about the different challenges occurs while detecting diabetic retinopathy using computer vision, deep learning techniques. Therefore, a purpose of this review paper is to sum up all the major aspects while detecting DR like lesion identification, classification and segmentation, security attacks on the deep learning models, proper categorization of datasets and evaluation metrics. As deep learning models are quite expensive and more prone to security attacks thus, in future it is advisable to develop a refined, reliable and robust model which overcomes all these aspects which are commonly found while designing deep learning models.

Progress of Imaging in Diabetic Retinopathy-From the Past to the Present

Advancement of imaging technology in retinal diseases provides us more precise understanding and new insights into the diseases' pathologies. Diabetic retinopathy (DR) is one of the leading causes of sight-threatening retinal diseases worldwide. Colour fundus photography and fluorescein angiography have long been golden standard methods in detecting retinal vascular pathology in this disease. One of the major advancements is macular observation given by optical coherence tomography (OCT). OCT dramatically improves the diagnostic quality in macular edema in DR. The technology of OCT is also applied to angiography (OCT angiograph: OCTA), which enables retinal vascular imaging without venous dye injection. Similar to OCTA, in terms of their low invasiveness, single blue color SLO image could be an alternative method in detecting non-perfused areas. Conventional optical photography has been gradually replaced to scanning laser ophthalmoscopy (SLO), which also make it possible to produce spectacular ultra-widefield (UWF) images. Since retinal vascular changes of DR are found in the whole retina up to periphery, it would be one of the best targets in UWF imaging. Additionally, evolvement of artificial intelligence (AI) has been applied to automated diagnosis of DR, and AI-based DR management is one of the major topics in this field. This review is trying to look back on the progress of imaging of DR comprehensively from the past to the present.

Prevention of vision-threatening complications in diabetic retinopathy: two perspectives based on results from the DRCR Retina Network Protocol W and the Regeneron-sponsored PANORAMA

PURPOSE OF REVIEW

The use of intravitreous antivascular endothelial growth factor to prevent center-involved diabetic macular edema (CI-DME) with vision loss and proliferative diabetic retinopathy (PDR) has been investigated and recently reported in two randomized clinical trials. Although both trials showed substantial superiority of aflibercept at preventing the development of vision-threatening complications (VTCs) of CI-DME or PDR compared with sham at 1 or 2 years, without a concomitant benefit in visual acuity outcomes, the interpretation of the results and its application to clinical practice resulted in two disparate opinions. In this review, we discuss these two trials including their similarities and differences, other relevant studies, and considerations regarding the interpretation and the application of these results into clinical practice.

RECENT FINDINGS

The Diabetic Retinopathy Clinical Research Retina Network Protocol W and the PANORAMA study demonstrated significantly lower probabilities of developing CI-DME or PDR at 2 years with intravitreous aflibercept compared with sham in eyes with moderate (Protocol W) or moderately severe (PANORAMA) to severe non-PDR (NPDR). However, visual acuity outcomes were not different.

SUMMARY

Although intravitreous aflibercept injections reduce the risk of VTCs in eyes with moderate-to-severe NPDR, the absence of visual acuity benefits supports the need for four-year results.

Altered oxylipin levels in human vitreous indicate imbalance in pro-/anti-inflammatory homeostasis in proliferative diabetic retinopathy

Proliferative diabetic retinopathy (PDR) is an advanced stage of diabetic retinopathy (DR), characterized by retinal neovascularization. It is a progressive fundus disease and a severe complication of diabetes that causes vision impairment. Hyperglycemia-induced persistent low-grade inflammation is a crucial factor underlying the pathogenesis of DR-associated damage and contributing to the progression of PDR. Highly enriched polyunsaturated fatty acids (PUFAs) in the retina are precursors to oxidized metabolites, namely, oxylipins, which exert pro-inflammatory or anti-inflammatory (resolving) effects under different pathological conditions and have been implicated in diabetes. To evaluate differences in oxylipin levels in the vitreous obtained from PDR and non-diabetic subjects, we performed a targeted assessment of oxylipins. A total of 41 patients with PDR and 22 non-diabetic control subjects were enrolled in this study. Vitreous humor obtained during routinely scheduled vitrectomy underwent a targeted but unbiased screening for oxylipins using mass spectrometry-based lipidomics. We found 21 oxylipins showing statistically significant differences in their levels between PDR and non-diabetic subjects (p < 0.05). Lipoxygenase (LOX)- and cytochrome P450 (CYP)- derived oxylipins were the most affected, while cyclooxygenase (COX) oxylipins were affected to a lesser extent. When categorized by their precursor PUFAs, ±19,20-EpDPE, a CYP product of docosahexaenoic acid (DHA) and 12S-HETE, a LOX product of arachidonic acid (ARA), were increased by the largest magnitude. Moreover, of these 21 oxylipins, 7 were considered as potential biomarkers for discriminating PDR patients from the non-diabetic controls. Our results indicate that altered oxylipin levels in the vitreous implicate an underlying imbalanced inflammation-resolution homeostasis in PDR.

A Systematic Review of Carotenoids in the Management of Diabetic Retinopathy

Diabetic retinopathy, which was primarily regarded as a microvascular disease, is the leading cause of irreversible blindness worldwide. With obesity at epidemic proportions, diabetes-related ocular problems are exponentially increasing in the developed world. Oxidative stress due to hyperglycemic states and its associated inflammation is one of the pathological mechanisms which leads to depletion of endogenous antioxidants in retina in a diabetic patient. This contributes to a cascade of events that finally leads to retinal neurodegeneration and irreversible vision loss. The xanthophylls lutein and zeaxanthin are known to promote retinal health, improve visual function in retinal diseases such as age-related macular degeneration that has oxidative damage central in its etiopathogenesis. Thus, it can be hypothesized that dietary supplements with xanthophylls that are potent antioxidants may regenerate the compromised antioxidant capacity as a consequence of the diabetic state, therefore ultimately promoting retinal health and visual improvement. We performed a comprehensive literature review of the National Library of Medicine and Web of Science databases, resulting in 341 publications meeting search criteria, of which, 18 were found eligible for inclusion in this review. Lutein and zeaxanthin demonstrated significant protection against capillary cell degeneration and hyperglycemia-induced changes in retinal vasculature. Observational studies indicate that depletion of xanthophyll carotenoids in the macula may represent a novel feature of DR, specifically in patients with type 2 or poorly managed type 1 diabetes. Meanwhile, early interventional trials with dietary carotenoid supplementation show promise in improving their levels in serum and macular pigments concomitant with benefits in visual performance. These findings provide a strong molecular basis and a line of evidence that suggests carotenoid vitamin therapy may offer enhanced neuroprotective effects with therapeutic potential to function as an adjunct nutraceutical strategy for management of diabetic retinopathy.

Combination Antivascular Endothelial Growth Factor and Modified Panretinal Photocoagulation in Management of Proliferative Diabetic Retinopathy

Purpose:

This work evaluates the effects of combined intravitreal antivascular endothelial growth factor (anti-VEGF) and modified panretinal photocoagulation (PRP) for management of proliferative diabetic retinopathy (PDR).

Methods:

This retrospective case series included 37 eyes of 33 patients with high-risk PDR. Anti-VEGF injections (≥ 2) were followed by modified, midperipheral PRP performed in 2 or more sessions. Visual and anatomic outcomes were tracked for 1 year after treatment. Regression analysis was performed for factors predictive of final outcomes.

Results:

Mean visual acuity (VA) at initial and final visit were 20/50 and 20/40 ( P = .22), respectively, over a mean follow-up duration of 341.4 days. Central foveal thickness decreased from 321.8 µm to 258.6 µm ( P = .01). Resolution of PDR was achieved in 94.6% of eyes, with 5.4% of eyes requiring additional anti-VEGF for persistent neovascularization. Final VA was significantly associated with baseline VA, VA at 1 month, and any adverse anatomical events. Treatment noncompliance was present in 24.3%; compliance decreased with increasing medical comorbidities, but was not significantly associated with final VA.

Conclusions:

Combination of anti-VEGF and modified PRP preserved VA and yielded PDR regression in the majority of eyes. This combination provides rapid PDR regression with anti-VEGF while achieving durable disease suppression in this real-world cohort without traditional PRP.