Diabetic Eye Disease

Diabetic optic neuropathy (DON) is a diverse complication of diabetes and its pathogenesis has not been fully elucidated. The purpose of this study was to explore dynamic cerebral activity changes in DON patients using dynamic amplitude of low-frequency fluctuation (dALFF). In total, 22 DON patients and 22 healthy controls were enrolled. The dALFF approach was used in all participants to investigate dynamic intrinsic brain activity differences between the two groups. Compared with HCs, DON patients exhibited significantly increased dALFF variability in the right middle frontal gyrus (P < 0.01). Conversely, DON patients exhibited obviously decreased dALFF variability in the right precuneus (P < 0.01). We also found that there were significant negative correlations between HADS scores and dALFF values of the right middle frontal gyrus in the DON patients (r = -0.6404, P <0.01 for anxiety and r = -0.6346, P <0.01 for depression; HADS, Hospital Anxiety and Depression Scale). Abnormal variability of dALFF was observed in specific areas of the cerebrum in DON patients, which may contribute to distinguishing patients with DON from HCs and a better understanding of DON, hyperintensities of right middle frontal gyrus may be potential diagnostic marker for DON.

Importance: Methods that increase visible retinal area (VRA; measured in millimeters squared) may improve identification of diabetic retinopathy (DR) lesions. Objective: To evaluate the association of dilation and manual eyelid lifting (MLL) with VRA on ultra-widefield imaging (UWFI) and the association of VRA with grading of DR severity and detection of predominantly peripheral lesions (PPLs). Design, Setting, and Participants: Retrospective, comparative case-control study at the Joslin Diabetes Center, Boston, Massachusetts. Nonmydriatic UWFI with MLL was acquired from a DR teleophthalmology program (Joslin Vision Network [JVN]). A second cohort of mydriatic UWFI was acquired at an academic retina practice (Beetham Eye Institute [BEI]) from November 6, 2017, to November 6, 2018, and with MLL thereafter until November 6, 2019. Fully automated algorithms determined VRA and hemorrhage and/or microaneurysm (HMA) counts. Predominantly peripheral lesions and HMAs were defined as present when at least 1 field had greater HMA number in the peripheral retina than within the corresponding Early Treatment Diabetic Retinopathy Study field. Participants included 3014 consecutive patients (5919 eyes) undergoing retinal imaging at JVN and BEI. Exposures: Dilation and MLL performed at the time of UWFI. Main Outcomes and Measures: Visible retinal area, DR severity, and presence of PPLs. Results: Of the 3014 participants, mean (SD) age was 56.1 (14.5) years, 1302 (43.2%) were female, 2450 (81.3%) were White, and mean (SD) diabetes duration was 15.9 (11.4) years. All images from 5919 eyes with UWFI were analyzed. Mean (SD) VRA was 665.1 (167.6) mm2 for all eyes (theoretical maximal VRA, 923.9 mm2), 550.8 (240.7) mm2 for nonmydriatic JVN with MLL (1418 eyes [24.0%]), 688.1 (119.9) mm2 for mydriatic BEI images (3650 eyes [61.7%]), and 757.0 (69.7) mm2 for mydriatic and MLL BEI images (851 eyes [14.4%]). Dilation increased VRA by 25% (P < .001) and MLL increased VRA an additional 10% (P < .001). Nonmydriatic MLL increased VRA by 11.0%. With MLL, HMA counts in UWFI fields increased by 41.7% (from 4.8 to 6.8; P < .001). Visible retinal area was moderately associated with increasing PPL-HMA overall and in each cohort (all, r = 0.33; BEI, r = 0.29; JVN, r = 0.36; P < .001). In JVN images, increasing VRA was associated with more PPL-HMA (quartile 1 [Q1], 23.7%; Q2, 45.8%; Q3, 60.6%; and Q4, 69.2%; P < .001). Conclusions and Relevance: Using fully automated VRA and HMA detection algorithms, pupillary dilation and eyelid lifting were shown to substantially increase VRA and PLL-HMA detection. Given the importance of HMA and PPL for determining risk of DR progression, these findings emphasize the importance of maximizing VRA for optimal risk assessment in clinical trials and teleophthalmology programs.

Diabetic retinopathy (DR) is a sight-threatening complication of diabetes mellitus (DM) and it contributes substantially to the burden of disease globally. During the last decades, the development of multiple imaging modalities to evaluate DR, combined with emerging treatment possibilities, has led to the implementation of large-scale screening programmes resulting in improved prevention of vision loss. However, not all patients are able to participate in such programmes and not all are at equal risk of DR development and progression. In this review, we discuss the relevance of the currently available imaging modalities for the evaluation of DR: colour fundus photography (CFP), ultrawide-field photography (UWFP), fundus fluorescein angiography (FFA), optical coherence tomography (OCT), OCT angiography (OCTA) and functional testing. Furthermore, we suggest where a particular imaging technique of DR may aid the evaluation of the disease in different clinical settings. Combining information from various imaging modalities may enable the design of more personalized care including the initiation of treatment and understanding the progression of disease more adequately.

BACKGROUND: To reduce treatment burden and optimise patient outcomes in diabetic macular oedema, we present 1-year results from two phase 3 trials of faricimab, a novel angiopoietin-2 and vascular endothelial growth factor-A bispecific antibody. METHODS: YOSEMITE and RHINE were randomised, double-masked, non-inferiority trials across 353 sites worldwide. Adults with vision loss due to centre-involving diabetic macular oedema were randomly assigned (1:1:1) to intravitreal faricimab 6·0 mg every 8 weeks, faricimab 6·0 mg per personalised treatment interval (PTI), or aflibercept 2·0 mg every 8 weeks up to week 100. PTI dosing intervals were extended, maintained, or reduced (every 4 weeks up to every 16 weeks) based on disease activity at active dosing visits. The primary endpoint was mean change in best-corrected visual acuity at 1 year, averaged over weeks 48, 52, and 56. Efficacy analyses included the intention-to-treat population (non-inferiority margin 4 Early Treatment Diabetic Retinopathy Study [ETDRS] letters); safety analyses included patients with at least one dose of study treatment. These trials are registered with ClinicalTrials.gov (YOSEMITE NCT03622580 and RHINE NCT03622593). FINDINGS: 3247 patients were screened for eligibility in YOSEMITE (n=1532) and RHINE (n=1715). After exclusions, 940 patients were enrolled into YOSEMITE between Sept 5, 2018, and Sept 19, 2019, and 951 patients were enrolled into RHINE between Oct 9, 2018, and Sept 20, 2019. These 1891 patients were randomly assigned to faricimab every 8 weeks (YOSEMITE n=315, RHINE n=317), faricimab PTI (n=313, n=319), or aflibercept every 8 weeks (n=312, n=315). Non-inferiority for the primary endpoint was achieved with faricimab every 8 weeks (adjusted mean vs aflibercept every 8 weeks in YOSEMITE 10·7 ETDRS letters [97·52% CI 9·4 to 12·0] vs 10·9 ETDRS letters [9·6 to 12·2], difference -0·2 ETDRS letters [-2·0 to 1·6]; RHINE 11·8 ETDRS letters [10·6 to 13·0] vs 10·3 ETDRS letters [9·1 to 11·4] letters, difference 1·5 ETDRS letters [-0·1 to 3·2]) and faricimab PTI (YOSEMITE 11·6 ETDRS letters [10·3 to 12·9], difference 0·7 ETDRS letters [-1·1 to 2·5]; RHINE 10·8 ETDRS letters [9·6 to 11·9], difference 0·5 ETDRS letters [-1·1 to 2·1]). Incidence of ocular adverse events was comparable between faricimab every 8 weeks (YOSEMITE n=98 [31%], RHINE n=137 [43%]), faricimab PTI (n=106 [34%], n=119 [37%]), and aflibercept every 8 weeks (n=102 [33%], n=113 [36%]). INTERPRETATION: Robust vision gains and anatomical improvements with faricimab were achieved with adjustable dosing up to every 16 weeks, demonstrating the potential for faricimab to extend the durability of treatment for patients with diabetic macular oedema. FUNDING: F Hoffmann-La Roche.

Microaneurysms (MAs) are one of the earliest clinically visible signs of diabetic retinopathy (DR). MA leakage or rupture may precipitate local pathology in the surrounding neural retina that impacts visual function. Thrombosis in MAs may affect their turnover time, an indicator associated with visual and anatomic outcomes in the diabetic eyes. In this work, we perform computational modeling of blood flow in microchannels containing various MAs to investigate the pathologies of MAs in DR. The particle-based model employed in this study can explicitly represent red blood cells (RBCs) and platelets as well as their interaction in the blood flow, a process that is very difficult to observe in vivo. Our simulations illustrate that while the main blood flow from the parent vessels can perfuse the entire lumen of MAs with small body-to-neck ratio (BNR), it can only perfuse part of the lumen in MAs with large BNR, particularly at a low hematocrit level, leading to possible hypoxic conditions inside MAs. We also quantify the impacts of the size of MAs, blood flow velocity, hematocrit and RBC stiffness and adhesion on the likelihood of platelets entering MAs as well as their residence time inside, two factors that are thought to be associated with thrombus formation in MAs. Our results show that enlarged MA size, increased blood velocity and hematocrit in the parent vessel of MAs as well as the RBC-RBC adhesion promote the migration of platelets into MAs and also prolong their residence time, thereby increasing the propensity of thrombosis within MAs. Overall, our work suggests that computational simulations using particle-based models can help to understand the microvascular pathology pertaining to MAs in DR and provide insights to stimulate and steer new experimental and computational studies in this area.

PURPOSE: Estimates of diabetic eye disease in American Indian and Alaska Natives (AI/AN) vary over time, region, and methods. This article reports recent prevalence of diabetic retinopathy (DR) and diabetic macular edema (DME) in AI/AN served by the Indian Health Services' (IHS) teleophthalmology program, as identified using ultrawide field imaging (UWFI). METHODS: This was a retrospective analysis of 2016-2019 clinical data (n = 53,900). UWF images were acquired by certified imagers using a validated protocol, and graded by licensed, certified optometrists supervised by an ophthalmologist. Graders evaluated the extent/severity of retinal lesions in comparison to standard photographs. DR lesions predominantly in any peripheral field were considered "predominantly peripheral lesions" (PPL). The analyses calculated prevalence of any DR, any DME, DR and DME severity, sight-threatening disease, and PPL. RESULTS: Patients averaged 56 years of age with a 68 mmol/mol A1c and 55% had had diabetes for 5+ years. Prevalence of any DR, any DME, and sight-threatening disease was 28.6%, 3.0%, and 3.0%. In patients with mild nonproliferative DR, PPL was seen in 25.3%. PPL suggested a more severe level of DR in 8.7% of patients. DR increased with age. DME decreased with age. Males and patients in the Nashville IHS area had more diabetic eye disease. CONCLUSION: AI/AN have a high burden of diabetes and its complications. The IHS is resource-constrained, making accurate disease estimates necessary for resource allocation and budget justifications to Congress. These data update the estimates of diabetic eye disease in Indian Country and suggest that UWFI identifies early DR.

PURPOSE: To determine if treatment with a photobiomodulation (PBM) device results in greater improvement in central subfield thickness (CST) than placebo in eyes with center-involved diabetic macular edema (CI-DME) and good vision. DESIGN: Phase 2 randomized clinical trial. PARTICIPANTS: Participants had CI-DME and visual acuity (VA) 20/25 or better in the study eye and were recruited from 23 clinical sites in the United States. METHODS: One eye of each participant was randomly assigned 1:1 to a 670-nm light-emitting PBM eye patch or an identical device emitting broad-spectrum white light at low power. Treatment was applied for 90 seconds twice daily for 4 months. MAIN OUTCOME MEASURES: Change in CST on spectral-domain OCT at 4 months. RESULTS: From April 2019 to February 2020, 135 adults were randomly assigned to either PBM (n = 69) or placebo (n = 66); median age was 62 years, 37% were women, and 82% were White. The median device compliance was 92% with PBM and 95% with placebo. OCT CST increased from baseline to 4 months by a mean (SD) of 13 (53) μm in PBM eyes and 15 (57) μm in placebo eyes, with the mean difference (95% confidence interval [CI]) being -2 (-20 to 16) μm (P = 0.84). CI-DME, based on DRCR Retina Network sex- and machine-based thresholds, was present in 61 (90%) PBM eyes and 57 (86%) placebo eyes at 4 months (adjusted odds ratio [95% CI] = 1.30 (0.44-3.83); P = 0.63). VA decreased by a mean (SD) of -0.2 (5.5) letters and -0.6 (4.6) letters in the PBM and placebo groups, respectively (difference [95% CI] = 0.4 (-1.3 to 2.0) letters; P = 0.64). There were 8 adverse events possibly related to the PBM device and 2 adverse events possibly related to the placebo device. None were serious. CONCLUSIONS: PBM as given in this study, although safe and well-tolerated, was not found to be effective for the treatment of CI-DME in eyes with good vision.

PURPOSE: To calculate costs required to prevent center-involved diabetic macular edema (CI-DME) or proliferative diabetic retinopathy (PDR), and to improve the diabetic retinopathy severity score (DRSS) with intravitreal anti-VEGF injections, as reported for aflibercept in 2 randomized control trials. DESIGN: Cost-effectiveness analysis modeling based on published data. SUBJECTS: None. METHODS: Results from PANORAMA and the Diabetic Retinopathy Clinical Research Network Protocol W were analyzed. Parameters collected included DRSS, risk reduction of PDR, risk reduction of CI-DME, and the number of treatments required. Costs were modeled based on 2020 Medicare reimbursement data practice settings of hospital-based facility and nonfacility. MAIN OUTCOME MEASURES: Cost to prevent cases of PDR and CI-DME and to improve DRSS stage. RESULTS: Over 2 years in Protocol W, the cost required to prevent 1 case of PDR was $83 000 ($72 400) in the facility (nonfacility) setting; in PANORAMA, the corresponding 2-year costs were $89 400 ($75 000) for the 2-mg aflibercept every 16 weeks (2Q16) arm, and $91 200 ($89 900) for the 2-mg aflibercept every 8 weeks as needed (2Q8PRN) arm. To prevent 1 case of CI-DME with vision loss in Protocol W, the cost was $154 000 ($133 000). For all CI-DME, with and without vision loss, in PANORAMA, the costs to prevent a case were $70 900 ($59 500) for the 2Q16 arm and $90 000 ($88 800) for the 2Q8PRN arm. In Protocol W, the overall accumulated total for cost/DRSS unit change at the 2-year point for facility (nonfacility) setting was $2700 ($2400)/DRSS. In the first year alone, it was $2100 ($1800)/DRSS and in the second year, it was $6100 ($5300)/DRSS. CONCLUSIONS: There is a considerable cost associated with the prevention of PDR and CI-DME with intravitreal aflibercept injections. A price per unit of change in DRSS is a new parameter that might serve as a benchmark in future utility analyses that could be used to bring the perspective to cost-utility considerations.

PURPOSE: To review the evidence on the safety and efficacy of current anti-vascular endothelial growth factor (VEGF) and intravitreal corticosteroid pharmacotherapies for the treatment of diabetic macular edema (DME). METHODS: Literature searches were last conducted on May 13, 2020, in the PubMed database with no date restrictions and limited to articles published in English. The combined searches yielded 230 citations, of which 108 were reviewed in full text. Of these, 31 were deemed appropriate for inclusion in this assessment and were assigned a level of evidence rating by the panel methodologist. RESULTS: Only the 21 articles with level I evidence were included in this assessment. Seventeen articles provided level I evidence for 1 or more anti-VEGF pharmacotherapies, including ranibizumab (14), aflibercept (5), and bevacizumab (2) alone or in combination with other treatments for DME. Level I evidence was identified in 7 articles on intravitreal corticosteroid therapy for treatment of DME: triamcinolone (1), dexamethasone (4), and fluocinolone acetonide (2). CONCLUSIONS: Review of the available literature indicates that intravitreal injections of anti-VEGF agents and corticosteroids are efficacious treatments for DME. Elevated intraocular pressure and cataract progression are important potential complications of corticosteroid therapy. Further evidence is required to assess the comparative efficacy of these therapies. Given the limited high-quality comparative efficacy data, choice of therapy must be individualized for each patient and broad therapeutic access for patients is critical to maximize outcomes.

To identify functionally related genes associated with diabetic retinopathy (DR) risk using gene set enrichment analyses applied to genome-wide association study meta-analyses. METHODS: We analyzed DR GWAS meta-analyses performed on 3246 Europeans and 2611 African Americans with type 2 diabetes. Gene sets relevant to 5 key DR pathophysiology processes were investigated: tissue injury, vascular events, metabolic events and glial dysregulation, neuronal dysfunction, and inflammation. Keywords relevant to these processes were queried in 4 pathway and ontology databases. Two GSEA methods, Meta-Analysis Gene set Enrichment of variaNT Associations (MAGENTA) and Multi-marker Analysis of GenoMic Annotation (MAGMA), were used. Gene sets were defined to be enriched for gene associations with DR if the P value corrected for multiple testing (Pcorr) was <.05. RESULTS: Five gene sets were significantly enriched for numerous modest genetic associations with DR in one method (MAGENTA or MAGMA) and also at least nominally significant (uncorrected P < .05) in the other method. These pathways were regulation of the lipid catabolic process (2-fold enrichment, Pcorr = .014); nitric oxide biosynthesis (1.92-fold enrichment, Pcorr = .022); lipid digestion, mobilization, and transport (1.6-fold enrichment, P = .032); apoptosis (1.53-fold enrichment, P = .041); and retinal ganglion cell degeneration (2-fold enrichment, Pcorr = .049). The interferon gamma (IFNG) gene, previously implicated in DR by protein-protein interactions in our GWAS, was among the top ranked genes in the nitric oxide pathway (best variant P = .0001). CONCLUSIONS: These GSEA indicate that variants in genes involved in oxidative stress, lipid transport and catabolism, and cell degeneration are enriched for genes associated with DR risk. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

AIMS: To compare the efficacy of diabetic retinal neovascularisation (NV) detection using the widefield swept-source optical coherence tomography angiography (WF SS-OCTA) vitreoretinal interface (VRI) Angio slab and SS-OCT VRI Structure slab. METHODS: A prospective, observational study was performed at Massachusetts Eye and Ear from January 2019 to June 2020. Patients with proliferative diabetic retinopathy (PDR), patients with non-proliferative diabetic retinopathy and patients with diabetes but without diabetic retinopathy were included. All patients were imaged with WF SS-OCTA using the 12×12 mm Angio scan protocol centred on the fovea and optic disc. The en-face SS-OCTA VRI Angio slab and SS-OCT VRI Structure slab were evaluated for the presence or absence of NV. SS-OCTA B-scan was used to classify NV according to cross-sectional morphology (forward, tabletop or flat). All statistical analyses were performed using SPSS V.26.0. RESULTS: One hundred and forty-two eyes of 89 participants were included in the study. VRI Angio detected NV at higher rates compared with VRI Structure (p<0.05). Combining VRI Angio and Structure improved detection rates compared with VRI Angio alone (p<0.05). Due to segmentation errors of the internal limiting membrane, NV with flat morphological classification had lower rates of detection on VRI Angio compared with NV with forward and tabletop morphology (p<0.05). CONCLUSIONS: WF SS-OCTA 12×12 mm VRI Angio and SS-OCT VRI Structure imaging centred on the fovea and optic disc detected NV with high sensitivity and low false positives. The VRI slab may be useful to diagnose and monitor PDR in clinical practice.

Purpose: Develop equations to convert Cirrus central subfield thickness (CST) to Spectralis CST equivalents and vice versa in eyes with diabetic macular edema (DME). Methods: The DRCR Retina Network Protocol O data were split randomly to train (70% sample) and validate (30% sample) conversion equations. Data from an independent study (CADME) also validated the equations. Bland-Altman 95% limits of agreement between predicted and observed values evaluated the equations. Results: Protocol O included 374 CST scan pairs from 187 eyes (107 participants). The CADME study included 150 scan pairs of 37 eyes (37 participants). Proposed conversion equations are Spectralis = 40.78 + 0.95 × Cirrus and Cirrus = 1.82 + 0.94 × Spectralis regardless of age, sex, or CST. Predicted values were within 10% of observed values in 101 (90%) of Spectralis and 99 (88%) of Cirrus scans in the validation data; and in 136 (91%) of the Spectralis and 148 (99%) of the Cirrus scans in the CADME data. Adjusting for within-eye correlations, 95% of conversions are estimated to be within 17% (95% confidence interval, 14%-21%) of CST on Spectralis and within 22% (95% confidence interval, 18%-28%) of CST on Cirrus. Conclusions: Conversion equations developed in this study allow the harmonization of CST measurements for eyes with DME using a mix of current Cirrus and Spectralis device images. Translational Relevance: The CSTs measured on Cirrus and Spectralis devices are not directly comparable owing to outer boundary segmentation differences. Converting CST values across spectral domain optical coherence tomography instruments should benefit both clinical research and standard care efforts.

Importance: The follow-up schedule for individuals with eyes treated with anti-vascular endothelial growth factor agents for proliferative diabetic retinopathy (PDR) requires that patients return frequently for monitoring and repeated treatment. The likelihood that a patient will comply should be a consideration in choosing a treatment approach. Objective: To describe completion of scheduled examinations among participants assigned to intravitreous injections of ranibizumab for PDR in a multicenter randomized clinical trial. Design, Setting, and Participants: This post hoc analysis evaluates data from a randomized clinical trial conducted at 55 US sites among 305 adults with proliferative diabetic retinopathy enrolled between February and December 2012. Both eyes were enrolled for 89 participants (1 eye to each study group), with a total of 394 study eyes. The final 2-year visit was completed in January 2015. Data were analyzed from April 2019 to July 2021. Interventions: Ranibizumab injections for PDR or macular edema. Main Outcomes and Measures: A long lapse in care of 8 or more weeks past a scheduled examination, dropout from follow-up, visual acuity at 5 years. Results: Among 170 participants, the median age was 51 years, and 44.7% were female. Through 5 years of follow-up, 94 of 170 participants (55.3%) had 1 or more long lapse in care. Median time to the first long lapse was 210 weeks, and 69 of 94 participants (73.4%) returned for examination after the first long lapse. Fifty of 170 participants (29.4%) dropped out of follow-up by 5 years. Among the 120 participants who completed the 5-year examination, median change from baseline in visual acuity was -2 letters for participants who had 1 or more long lapse compared with +5 letters for those without a long lapse (P = .02). After multivariable adjustment, the odds ratio (95% CI) for baseline associations with 1 or more long lapse was 1.21 (1.03-1.43) for each 5-letter decrement in visual acuity score, 2.19 (1.09-4.38) for neovascularization of the disc and elsewhere, and 3.48 (1.38-8.78) for no prior laser treatment for diabetic macular edema. Conclusions and Relevance: Over 5 years, approximately half of the participants assigned to ranibizumab for PDR had a long lapse in care despite substantial effort by the DRCR Retina Network to facilitate timely completion of examinations. The likelihood of a long lapse in care during long-term follow-up needs to be considered when choosing treatment for PDR. Trial Registration: ClinicalTrials.gov Identifier: NCT01489189.