Next-generation anti-VEGF agents for diabetic macular oedema

Efficacy and safety of dexamethasone versus intravitreal aflibercept implants for macular edema: a systematic review and meta-analysis

BACKGROUND

Macular edema (ME) is a prevalent complication of diabetic retinopathy (DR) and retinal vein occlusion (RVO) that contributes significantly to vision impairment worldwide. This condition is primarily driven by elevated vascular endothelial growth factor (VEGF) and pro-inflammatory cytokines, resulting in the use of anti-VEGF agents such as aflibercept and corticosteroids such as dexamethasone implants. However, evidence comparing the clinical efficacy and safety of these two modalities remains limited.

OBJECTIVES

This systematic review and meta-analysis aimed to compare the safety and efficacy of intravitreal aflibercept injections and dexamethasone implants in ME associated with DR and RVO.

METHOD

The study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and registered with PROSPERO (CRD42024577212). A comprehensive search of the PubMed, Cochrane, Web of Science, and Scopus databases was performed until August 30, 2024. Nine studies, involving 572 eyes, were included in the analysis. Key outcomes assessed included Best-Corrected Visual Acuity (BCVA), Central Retinal Thickness (CRT), and Intraocular Pressure (IOP). A random-effects model was applied to the pooled effect size calculations, and heterogeneity was addressed using sensitivity analyses.

RESULTS

Both treatments showed comparable efficacy in improving BCVA and reducing CRT across follow-up intervals. At 3 months, dexamethasone implants demonstrated statistically significant superiority in BCVA improvement (MD = 1.18, 95% CI [0.89, 1.47], P < 0.001) and CRT reduction (MD =  - 62.45 µm, 95% CI [- 85.67, - 39.22], P < 0.001) compared to aflibercept. Similarly, at 12 months, dexamethasone implants maintained greater efficacy in CRT reduction (MD =  - 58.73 µm, 95% CI [- 78.12, - 39.34], P < 0.001). However, dexamethasone implants were associated with an increased IOP at 3 and 6 months (MD = 1.04 mmHg, 95% CI [0.56, 1.52], P < 0.001). No significant differences in IOP were observed between treatments at 12 months.

CONCLUSION

Intravitreal aflibercept injections and dexamethasone implants are effective modalities for the management of ME, with each presenting distinct advantages. Dexamethasone implants minimize the frequency of treatment, while achieving superior outcomes in terms of BCVA and CRT. However, they are also associated with a heightened risk of IOP elevation and cataract formation. Conversely, aflibercept requires more frequent administration, which may result in logistical and financial challenges for patients and health care providers. Therefore, personalized treatment strategies should consider disease severity, comorbidities, and individual preferences. Future research should prioritize patient-centered outcomes, emphasizing quality of life and treatment costs while also investigating condition-specific responses to these therapeutic interventions.

Diabetic retinopathy: a comprehensive review of pathophysiology and emerging treatments

Diabetic retinopathy constitutes a major complication associated with diabetes mellitus, resulting in visual impairment and blindness on a global scale. The pathophysiology of DR is characterized by intricate interactions among metabolic, hemodynamic, and inflammatory pathways, which include the activation of the polyol pathway, the accumulation of advanced glycation end products, the overactivation of protein kinase C, dysregulation of the renin-angiotensin-aldosterone system, and retinal neurodegeneration. This review investigates the classification, complex pathophysiology, and therapeutic modalities for DR, encompassing conventional interventions such as anti-VEGF agents, aldose reductase inhibitors, angiotensin receptor blockers, laser photocoagulation, and vitrectomy. Innovative treatments, including advanced anti-VEGF agents, neuroprotective strategies, gene and stem cell therapies, and advancements in drug delivery systems, exhibit considerable transformative potential. Furthermore, integrating artificial intelligence for early detection and modulation of inflammatory pathways signifies cutting-edge progress in the field. By integrating contemporary knowledge and prospective avenues, this review underscores the significance of comprehending the multifaceted nature of DR and the advancements in its therapeutic approaches. The objective is to bridge the gaps between research findings and clinical application, thereby providing a comprehensive resource to enhance outcomes and quality of life for individuals impacted by DR.

Hybrid Biomembrane-Functionalized Nanorobots Penetrate the Vitreous Body of the Eye for the Treatment of Retinal Vein Occlusion

Intravitreal injections of antivascular endothelial growth factor (VEGF) agents are the primary method for treating retinal vein occlusion (RVO). However, the complex structure of eye anatomy presents ocular barriers that impede drug delivery. Additionally, these drugs only manage the complications associated with RVO and fail to address the underlying cause of vessel occlusions. Here, we describe a method that utilizes functionalized magnetically driven nanorobots to overcome ocular barriers and treat RVO. These nanorobots are developed using a hybrid biomembrane that combines stem cell membranes with liposome-derived membranes, enveloping perfluorohexane, iron oxide nanoparticles, and l-arginine. After intravitreal injection, the nanorobots can move directionally through and penetrate the vitreous body to reach the retina, driven by an external magnetic field. Subsequently, the nanorobots actively target the inflammation sites at occluded vessels due to the presence of stem cell membranes. In a rat model of RVO, enhanced targeting and accumulation in ischemic retinal vessels were demonstrated following intravitreal injections. Furthermore, the application of ultrasound triggers the release of l-arginine at the site of occlusion, stimulating the production of nitric oxide, which promotes vasodilation and restores blood flow, thereby achieving excellent therapeutic efficacy for RVO. We believe these methods hold significant promise for overcoming challenges in ocular drug delivery and effectively treating RVO in clinical applications.

Natural remedies proposed for the management of diabetic retinopathy (DR): diabetic complications

Diabetic retinopathy (DR) represents a significant and serious complication associated with diabetes mellitus (DM), often resulting in considerable visual impairment or even blindness. The intricate pathological processes underlying DR complicate the effectiveness of current treatment modalities. Studies have highlighted the potential of natural products in the treatment of DR via several beneficial effects including anti-inflammatory, antioxidant, anti-neovascular, and anti-apoptotic properties. Flavonoids, saponins, saccharides, and alkaloids exhibited various beneficial effects in DR in in vivo and in vitro studies. However, the clinical utilization of these natural compounds is hindered by issues such as inadequate specificity, low bioavailability, and potential toxicity. Therefore, there is a pressing need for rigorous clinical studies to confirm the efficacy of natural products in preventing or mitigating the progression of DR.

Innovator ranibizumab ComparEd to Biosimilar ranibizumab in combination with Expansile gas in submaculaR HemorrhaGe: the ICEBERG study

PURPOSE

To compare the anatomical and visual outcomes in eyes with submacular hemorrhage (SMH) treated with a combination of ranibizumab (RBZ) either innovator or biosimilar (Razumab) and intravitreal perfluoropropane gas (C3F8).

METHODS

Treatment naïve neovascular age related macular degeneration (n-AMD) patients with SMH were retrospectively analyzed. Patients received either innovator or biosimilar RBZ (3 loading doses followed by pro re nata regimen) and single injection of intravitreal C3F8. Optical coherence tomography (OCT) was performed at baseline, 1, 3 and 6 months. Changes in best corrected visual acuity (BCVA) and central macular thickness (CMT) were assessed at 6 months. P value ≤ 0.05 was considered statistically significant.

RESULTS

A total of 67 eyes (35 and 32 eyes in innovator and biosimilar group respectively) were analyzed. BCVA improved from 1.15 ± 0.19 to 0.51 ± 0.23 logarithm of minimum angle of resolution (logMAR) in innovator RBZ group (p < 0.001) and from 1.17 ± 0.15 to 0.53 ± 0.20 logMAR in biosimilar RBZ group (p < 0.001). Similarly, mean CMT showed significant reduction in both groups at 6 months (innovator RBZ: 609.5 ± 50.1 μm to 254.3 ± 20.3 μm, p < 0.001; biosimilar RBZ: 602.3 ± 58.9 μm to 251.8 ± 22.3 μm, p < 0.001). Intergroup comparisons between innovator and biosimilar RBZ showed no differences in either BCVA or CMT at all time points (all p values > 0.05). Mean number of intravitreal injections was marginally higher in innovator group compared to biosimilar RBZ (4.37 ± 0.49 vs. 4.22 ± 0.42; p = 0.18).

CONCLUSION

Biosimilar RBZ may act as a viable alternative to innovator RBZ to treat SMH with comparable anatomical and visual outcomes at 6 months.

Efficacy & safety of brolucizumab 6.0 mg versus 3.6 mg in diabetic macular edema

BACKGROUND

Management of Diabetic Macular edema (DME) requires repeated injections. Therefore newer Anti-VEGFs like Brolucizumab with longer durability have been introduced. We compared two different dosages of Brolucizumab, 6.0 mg and 3.6 mg, for their safety & efficacy in treatment of DME, in treatment naïve patients over 52 weeks.

METHOD

A prospective, pilot randomised controlled, single centre, double blinded, two arm comparative study was conducted between Dec 2022 to Apr 2024. The study recruited 82 patients of DME who were randomised into two groups of 41 patients each, one group to be treated with Brolucizumab 6.0 mg in 50 μL and the other to receive 3.6 mg in 30 μL. All patients received the first dose of Brolucizumab at 0 week and were then followed up at every 4 weeks for detailed ophthalmic and OCT macula examination. Those who met the pre-defined re-treatment criteria were re-injected with Brolucizumab, the dose being fixed for each group throughout the study. All patient receiving an injection were further followed up on Day 1, Day 7 and Day 28 to look for any adverse reactions. The efficacy parameters included change in best corrected visusal acuity (BCVA), contrast and central macular thickness (CMT) on Optical Coherence Tomography. The average number of injections recd in each group were also calculated.

RESULTS

The change in BCVA from baseline in 6.0 mg group was 0.54 LogMAR units and 3.6 mg group was 0.59 LogMAR units, which was not statistically significant. The reduction in CMT from baseline in 6.0 mg group was 133.2 µm (μ) and 3.6 mg group was 110.6 μ, which was not statistically significant. The improvement in contrast from baseline in 6.0 mg group was 0.74 and 3.6 mg group was 0.95, with p value of 0.0002. The re-injection interval was 14.21 weeks in 6.0 mg group and 15.56 weeks for 3.6 mg subgroup. The total number of adverse events in both groups were similar at 70 in 6.0 mg group and 47 in 3.6 mg group with only one grade 4 adverse event occurring in each group.

CONCLUSION

The results of present study show that the safety and efficacy of both doses of Brolucizumab, i.e. 6.0 mg and 3.6 mg, for treating diabetic macular edema is similar. Trial registration Study was registered with Clinical trials registry of India (CTRI ref no. CTRI/2023/06/054105), registered on 14 Nov 2022.

The effect of diabetes on short-term outcomes following epiretinal membrane surgery

PURPOSE

This study aimed to examine the association of diabetes with anatomical and functional outcomes of epiretinal membrane surgery.

METHODS

Consecutive patients who underwent epiretinal membrane surgery between 2017-2021 at Helsinki University Hospital, Finland. Here we examined the association of diabetes, glycemic control, and requirement for insulin medication with surgical outcomes at 1-month.

RESULTS

Included were 214 eyes of 214 patients, with a mean age of 71.2 ± 8.2 years. Among patients with diabetes (n = 45), neither significant differences were observed in anatomical outcomes (- 47.8 ± 72.7 μm vs. - 38.3 ± 103 μm for foveal thickness, p = 0.566 and - 41.6 ± 61.8 μm vs. - 41.7 ± 85.7 μm for central subfield macular thickness, p = 0.996) nor in best-corrected visual acuity (BCVA) gain (0.06 ± 0.22 vs 0.12 ± 0.30 LogMAR units, p = 0.214) compared to those without diabetes. In a multivariate analysis adjusted for age, gender, the existence of preoperative macular cysts, and topical nonsteroidal anti-inflammatory drugs (NSAIDs) use, the results remained consistent. The last preoperative HbA1c levels did not correlate with changes in foveal (Pearson's r = 0.218, p = 0.264) or central subfield macular thickness (r = 0.365, p = 0.056), or with BCVA gain (r = -0.177, p = 0.386). Insulin therapy for diabetes did not associate with the outcomes (p > 0.05 for anatomical and functional comparisons).

CONCLUSIONS

In a cohort of patients who underwent epiretinal membrane surgery, neither the presence of diabetes, nor glycemic control and the use of insulin medication associated with the outcomes.

Multi-Omics Integration With Machine Learning Identified Early Diabetic Retinopathy, Diabetic Macula Edema and Anti-VEGF Treatment Response

Purpose

Identify optimal metabolic features and pathways across diabetic retinopathy (DR) stages, develop risk models to differentiate diabetic macular edema (DME), and predict anti-vascular endothelial growth factor (anti-VEGF) therapy response.

Methods

We analyzed 108 aqueous humor samples from 78 type 2 diabetes mellitus patients and 30 healthy controls. Ultra-high-performance liquid chromatography-high-resolution-mass-spectrometry detected lipidomics and metabolomics profiles. DME patients received ≥3 anti-VEGF treatments, categorized into strong and weak response groups. Machine learning (ML) screened prospective metabolic features, developing prediction models.

Results

Key metabolic features identified in the metabolomics and lipidomics datasets included n-acetyl isoleucine (odds ratio [OR] = 1.635), cis-aconitic acid (OR = 3.296), and ophthalmic acid (OR = 0.836) for DR. For early-DR, n-acetyl isoleucine (OR = 1.791) and decaethylene glycol (PEG-10) (OR = 0.170) were identified as key markers. L-kynurenine (OR = 0.875), niacinamide (OR = 0.843), and linoleoyl ethanolamine (OR = 0.941) were identified as significant indicators for DME. Trigonelline (OR = 1.441) and 4-methylcatechol-2-sulfate (OR = 1.121) emerged as predictors for strong response to anti-VEGF. Predictive models achieved R² values of 99.9%, 97.7%, 93.9%, and 98.4% for DR, early-DR, DME, and strong response groups in the calibration set, respectively, and validated well with R² values of 96.3%, 96.8%, 79.9%, and 96.3%.

Conclusions

This research used ML to identify differential metabolic features from metabolomics and lipidomics datasets in DR patients. It implies that metabolic indicators can effectively predict early disease progression and potential weak responders to anti-VEGF therapy in DME eyes.

Translational Relevance

The identified metabolic indicators may aid in predicting the early progression of DR and optimizing therapeutic strategies for DME.

Potential Drug Targets for Diabetic Retinopathy Identified Through Mendelian Randomization Analysis

Purpose

This study aimed to investigate the causal effect of plasma proteins on diabetic retinopathy (DR) risk and identify potential drug targets for this disease.

Methods

Two-sample Mendelian randomization was performed to explore potential drug targets for DR. A total of 734 proteins were selected as instrumental variables. The Steiger filtering test and colocalization analysis were conducted to determine the causal direction and genetic pleiotropy. Plasma proteins from the decode study were used to validate the findings.

Results

Eleven plasma proteins were associated with DR risk. Genetically predicted high levels of CCL3L1 (odds ratio [OR] = 0.582; 95% confidence interval [CI], 0.343-0.986; P = 0.044), PAM (OR = 0.782; 95% CI, 0.652-0.937; P = 0.008), GP1BA (OR = 0.793; 95% CI, 0.632-0.994; P = 0.044), GALNT16 (OR = 0.832; 95% CI, 0.727-0.952; P = 0.008), POGLUT1 (OR = 0.836; 95% CI = 0.703-0.995; P = 0.043), and DKK3 (OR = 0.859; 95% CI, 0.777-0.950; P = 0.003) have the protective effect on DR risk. Genetically predicted high levels of GFRA2 (OR = 1.104; 95% CI, 1.028-1.187; P = 0.007), PATE4 (OR = 1.405; 95% CI, 1.060-1.860; P = 0.018), GSTA1 (OR = 1.464; 95% CI, 1.163-1.842; P = 0.001), SIRPG (OR = 1.600, 95% CI, 1.244-2.057; P = 2.51E-04), and MAPK13 (OR = 1.731; 95% CI, 1.233-2.431; P = 0.002) were associated with an increased risk of DR. However, the colocalization analysis results suggested that SIRPG and GP1BA have a shared causal variant with DR.

Conclusions

CCL3L1, PAM, GALNT16, POGLUT1, DKK3, GFRA2, PATE4, GSTA1, and MAPK13 were associated with DR risk and were identified as potential drug targets for DR.

Translational Relevance

The present study has highlighted the role of CCL3L1, PAM, GALNT16, POGLUT1, DKK3, GFRA2, PATE4, GSTA1, and MAPK13 in the development of DR.

Is longer axial length protective of vision-threatening diabetic retinopathy across different ages? A multicenter cohort of 736 patients

PURPOSE

Vision-threatening diabetic retinopathy (VTDR) included severe non-proliferative diabetic retinopathy (NPDR), proliferative diabetic retinopathy (PDR) and clinically significant diabetic macular edema (DME). To compare the axial length (AL) and assess its influence on VTDR across different ages.

METHODS

A retrospective cohort study. Medical chart review was performed in 736 consecutive patients with VTDR. The patients were divided into young (≤ 45 years) and elderly group (> 45 years) based on their age at the diagnosis of VTDR. After at least one year of standardized treatments, all eligible patients were followed up. The main outcome measures included the presence of tractional retinal detachment (TRD) involving foveal, final best-corrected visual acuity (BCVA), the development of neovascular glaucoma (NVG), and recurrent vitreous hemorrhage (VH) post-vitrectomy. ALs were compared between two age groups. The impact of AL on clinical outcomes was determined by logistic analyses after controlling for systemic parameters.

RESULTS

The study included 144 patients ≤ 45 years and 592 patients > 45 years. Young patients had significantly longer AL than elderly participants (23.9 mm vs 23.0 mm, p < 0.001). Over a median follow-up of 25.9 months, a larger proportion of young patients developed TRD (34.7% vs 16.2%, p < 0.001) and recurrent VH (18.6% vs 10.3%, p = 0.040) than elderly patients. In elderly group, longer AL is an independent protective factor in preventing TRD (odds ratio [OR], 0.5; 95% confidence interval [CI], 0.4-0.7; P < 0.001). However, this beneficial effect was not observed in young patients.

CONCLUSIONS

Young patients with VTDR exhibited significantly longer AL but more aggressive clinical signs with compromised prognosis. In elderly group, a longer AL independently reduced the risk of TRD, while this protective effect did not exist for young patients.

Association Between VEGF-460C/T Gene Polymorphism and Risk of Diabetic Retinopathy in Type 2 Diabetes Mellitus: A Meta-Analysis

The aim of the study was to investigate the relationship between VEGF-460C/T polymorphism and susceptibility to diabetic retinopathy (DR) in type 2 diabetes mellitus (T2DM) by meta-analysis. A comprehensive search was conducted across six databases until September 2023 to identify studies examining the association between VEGF-460C/T polymorphism and susceptibility to DR. Data process was performed by Stata 15.0 software. Eight studies were included, involving 1463 patients with DR. In the overall analysis, the difference was statistically significant only in the homozygous model (CC vs. TT: OR=1.86, p=0.048). A subgroup analysis of 6 papers with genotype frequency satisfying HWE in the control group indicated significant differences among the allele (C vs. T: OR=1.34, p=0.037), recessive (CC vs. CT+TT: OR=1.96, p=0.022) and homozygous (CC vs. TT: OR=2.28, p=0.015) models. However, in the dominant and heterozygous models, the difference was not statistically significant. The sensitivity of the HWE-based subgroup analysis showed that the conclusions in other gene models except the heterozygote model were not robust. This meta-analysis indicated that VEGF-460C/T gene polymorphism is associated with susceptibility to DR in T2DM. Allele C and genotype CC at the VEGF-460C/T locus are associated with an increased risk of DR in T2DM. However, considering that the results are not robust, more trials involving more rigorous design are needed to verify the findings of this review in the future.

Recent advances in the treatment and delivery system of diabetic retinopathy

Diabetic retinopathy (DR) is a highly tissue-specific neurovascular complication of type 1 and type 2 diabetes mellitus and is among the leading causes of blindness worldwide. Pathophysiological changes in DR encompass neurodegeneration, inflammation, and oxidative stress. Current treatments for DR, including anti-vascular endothelial growth factor, steroids, laser photocoagulation, and vitrectomy have limitations and adverse reactions, necessitating the exploration of novel treatment strategies. This review aims to summarize the current pathophysiology, therapeutic approaches, and available drug-delivery methods for treating DR, and discuss their respective development potentials. Recent research indicates the efficacy of novel receptor inhibitors and agonists, such as aldose reductase inhibitors, angiotensin-converting enzyme inhibitors, peroxisome proliferator-activated receptor alpha agonists, and novel drugs in delaying DR. Furthermore, with continuous advancements in nanotechnology, a new form of drug delivery has been developed that can address certain limitations of clinical drug therapy, such as low solubility and poor penetration. This review serves as a theoretical foundation for future research on DR treatment. While highlighting promising therapeutic targets, it underscores the need for continuous exploration to enhance our understanding of DR pathogenesis. The limitations of current treatments and the potential for future advancements emphasize the importance of ongoing research in this field.

Modeling early pathophysiological phenotypes of diabetic retinopathy in a human inner blood-retinal barrier-on-a-chip

Diabetic retinopathy (DR) is a microvascular disorder characterized by inner blood-retinal barrier (iBRB) breakdown and irreversible vision loss. While the symptoms of DR are known, disease mechanisms including basement membrane thickening, pericyte dropout and capillary damage remain poorly understood and interventions to repair diseased iBRB microvascular networks have not been developed. In addition, current approaches using animal models and in vitro systems lack translatability and predictivity to finding new target pathways. Here, we develop a diabetic iBRB-on-a-chip that produces pathophysiological phenotypes and disease pathways in vitro that are representative of clinical diagnoses. We show that diabetic stimulation of the iBRB-on-a-chip mirrors DR features, including pericyte loss, vascular regression, ghost vessels, and production of pro-inflammatory factors. We also report transcriptomic data from diabetic iBRB microvascular networks that may reveal drug targets, and examine pericyte-endothelial cell stabilizing strategies. In summary, our model recapitulates key features of disease, and may inform future therapies for DR.

Influence of prior treatment protocol on intravitreal dexamethasone implant behavior in patients with diabetic macular edema in real-world practice

BACKGROUND AND OBJECTIVE

Intravitreal dexamethasone implant (DEXI) has been placed as an effective option to treat diabetic macular edema (DME). However, there is no consensus on the best time to introduce it. We conducted a study to evaluate anatomical and functional behavior after the first DEXI according to previous treatment.

RESEARCH DESIGN AND METHODS

This retrospective, real-world study between 2013 and 2020 investigated changes in best-corrected visual acuity (BCVA) and central macular thickness (CMT at months 2 and 6 after the first DEXI in DME. Patients were divided into naive, early switch (≤3 anti-VEGF injections), or late switch (>3 anti-VEGF injections) groups.

RESULTS

Among 112 consecutive eyes, mean BCVA and CMT improved significantly in all groups at month 2, with no difference between them. However, this improvement was not maintained at 6 months. The Naíve group presented better BCVA all over the study period. The previously treated groups, which started with worse initial visual acuity, showed more visual gain without reaching the BCVA of the naive group. CMT performance was similar between groups.

CONCLUSIONS

There was similar anatomical and functional behavior in all groups. Poorer visual acuity at baseline was associated with worse functional outcome despite good anatomic response.

Correlation between serum microRNA-122 and VEGF expression and pregnancy outcome in gestational diabetes mellitus patients

Objective

Gestational diabetes mellitus (GDM) seriously influences the health of mothers and babies, and there are still no effective early diagnostic markers. Therefore, our study planned to probe the correlation between serum microRNA-122 and VEGF expression and pregnancy outcome in GDM patients.

Methods

This was a retrospective study of the correlation between serum microRNA-122 and vascular endothelial growth factor (VEGF) expression and pregnancy outcome in GDM patients. Sixty GDM patients admitted to the Fourth Hospital of Shijiazhuang from January 2021 to October 2022 were included in the research group (RG), and another 60 healthy pregnant women were included in the control group (CG). Serum miR-122 and VEGF levels were quantified using quantitative real-time polymerase chain reaction. The value of miR-122 and VEGF in predicting adverse pregnancy outcomes was analyzed by receiver operating characteristic curve.

Results

Serum miR-122 and VEGF levels in the RG were higher relative to the CG. The total occurrence of adverse pregnancy outcomes in the RG was higher relative to the CG (P<0.05). Serum miR-122 together with VEGF levels in the poor outcome group was higher relative to the good outcome group (P<0.05). ROC analysis revealed that miR-122 and VEGF could be used to predict adverse pregnancy outcome (P<0.0001). The area under the curve of miR-122 was 0.860, 95% confidence interval (CI) =0.793-0.926, and the area under the curve of VEGF was 0.780, 95% CI =0.694-0.866. Serum levels of miR-122, VEGF were positively related with abortion, preterm delivery, low birth weight infants, macrogenesis infants, and fetal development abnormalities (P<0.001).

Conclusion

The higher serum miR-122 and VEGF levels in GDM patients with satisfactory blood glucose control, the greater the probability of adverse pregnancy outcome, which should be paid attention to by clinicians.

Comparative efficacy and safety of Faricimab and other anti-VEGF therapy for age-related macular degeneration and diabetic macular edema: A systematic review and meta-analysis of randomized clinical trials

INTRODUCTION

A systematic review and meta-analysis were conducted to evaluate the efficacy and the overall safety of Faricimab compared with other anti-vascular endothelial growth factors (VEGF) therapy for neovascular age-related macular degeneration (AMD) and diabetic macular edema (DME).

MATERIALS AND METHODS

A systematic literature search of a comprehensive electronic database was performed to identify randomized clinical trials published from January 2013 to January 2023 for Faricimab in AMD and DME. Weighted mean differences and risk ratios were used to integrate the different studies.

RESULTS

A total of 4 randomized controlled trials (RCTs) with 1678 AMD patients and 3 RCTs with 20 DME patients were included in the meta-analysis.In patients with AMD, a significant difference was found in the number of injections between Faricimab and other anti-VEGF therapy (MD = -2.42, 95% CI [-3.93 to -0.90], P = .002).No significant difference was found for the change in best corrected visual acuity (BVCA), central subfoveal thickness (CST), and gaining 15 or more letters. Similarly, no significant difference was found for adverse events.In patients with DME, a significant difference was observed for CST (MD = -22.41, 95% CI [-29.95 to -14.86], P < .00001) and the number of injections(MD = -0.93, 95% CI [-1.33 to -0.54], P < .00001). No significant difference was found for BVCA and gaining 15 or more letters, and no significant difference was found for adverse events.

CONCLUSIONS

Comprehensive evidence confirms that Faricimab achieves non-inferior or even better CST improvement than other anti-VEGF therapies with extended dosing intervals, but more long-term follow-up studies are needed to support our conclusions.

Comparative Efficacy, Durability and Safety of Faricimab in the Treatment of Diabetic Macular Edema: A Systematic Literature Review and Network Meta-Analysis

INTRODUCTION

A systematic literature review (SLR) and network meta-analysis (NMA) were conducted to evaluate the comparative efficacy, durability and safety of faricimab, used in a Treat & Extend (T&E) regime with intervals up to every 16 weeks (Q16W), relative to other therapies currently in use for treatment of diabetic macular oedema (DME). Of particular interest were anti-vascular endothelial growth factor (VEGF) therapies applied in flexible dosing regimens such as Pro re nata (PRN) and T&E, which are the mainstay in clinical practice.

METHODS

An SLR identifying randomised controlled trials (RCTs) published before August 2021 was conducted, followed by a Bayesian NMA comparing faricimab T&E treatment to aflibercept, ranibizumab, bevacizumab, dexamethasone and laser therapy. Outcomes included in the analysis were change in best-corrected visual acuity (BCVA), change in central subfield thickness (CST), injection frequency, ocular adverse events (AE) and all-cause discontinuation, all of which were evaluated at 12 months. Subgroup analyses including patients' naïve to anti-VEGF were conducted where feasible.

RESULTS

Twenty-six studies identified in the SLR were included in the NMA. Most importantly for decision making in clinical practise, faricimab T&E was associated with a statistically greater (95% credible intervals exclude zero) and clinically meaningful decrease in retinal thickness compared to all other flexible dosing regimens (greater retinal drying by 55-125 microns). Anatomical outcomes determine treatment efficacy and retreatment of patients. The NMA also showed a statistically greater increase in mean change in BCVA for faricimab T&E vs. flexible regimens using ranibizumab and bevacizumab (increase of 4.4-4.8 letters) as well as a numerical improvement vs. aflibercept PRN (two letters, 95% credible intervals including zero). Accordingly, the injection frequency was numerically lower versus other treatments using flexible dosing regimens (decrease by 0.92-1.43 injections). The analyses also indicated that the safety profile of faricimab T&E was comparable to those of ranibizumab and aflibercept, which have well-established safety profiles, with similar results for the number of all-cause discontinuations.

CONCLUSION

Faricimab provides a new treatment option in DME with dual-pathway inhibition of VEGF and angiopoeitin-2 (Ang-2). To the authors' knowledge, this is the first indirect comparison of faricimab T&E in DME. The analyses indicate that faricimab T&E is associated with superior retinal drying along with numerically fewer injections compared to all other treatments given in flexible dosing regimens. It also showed superior visual acuity outcomes compared to ranibizumab and bevacizumab.

Analysis of Cytokine Levels Based on Optical Coherence Tomography Findings in Acute and Chronic Central Serous Chorioretinopathy

Purpose: To investigate the characteristics of optical coherence tomography (OCT) and aqueous humor cytokine differences between acute and chronic central serous chorioretinopathy (CSC) and to evaluate the relevance of these findings.Methods: This was a cross-sectional, observational study. Patients with CSC were divided into acute and chronic groups based on the symptom duration and were compared with normal controls. Best-corrected visual acuity (BCVA), central macular thickness (CMT), subfoveal choroidal thickness (CT), hyperreflective foci (HF), and cytokines including vascular endothelial growth factor (VEGF), interleukin (IL)-6, IL-8, IL-10, interferon-inducible protein-10 (IP-10), and monocyte chemoattractant protein-1 (MCP-1) were used as comparison metrics.Results: A total of 62 patients (62 eyes) with CSC (22 with acute CSC and 40 with chronic CSC) and 35 patients as controls were included in this study. The chronic CSC group had significantly older average ages and worse BCVA than the acute CSC group (both p < 0.05). Both CSC groups showed significant increases in CMT and CT (both p < 0.05). In chronic CSC, the CMT was thinner, with more HF in the neuroretina (p = 0.034). VEGF levels were significantly higher in patients with chronic CSC than in those with acute CSC and controls (p < 0.05). The levels of inflammatory cytokines showed no significant difference between the CSC and control groups. Spearman's correlation analysis showed that the number of HF was positively correlated with disease duration (r = 0.311, p = 0.014), logMAR BCVA (r = 0.487, P < 0.001) and MCP-1 levels (r = 0.256, p = 0.045).Conclusions: Chronicity of CSC could lead to upregulation of VEGF. HF was associated with a more severe visual impairment in CSC patients and had relations with the levels of MCP-1.

Accuracy of biomicroscopy, ultrasonography and spectral-domain OCT in detection of complete posterior vitreous detachment

BACKGROUND

To evaluate the accuracy of preoperative biomicroscopy (BM), ultrasonography (US), and spectral domain optical coherence tomography (SD-OCT) to determine complete posterior vitreous detachment (PVD) confirmed by intraoperative findings of triamcinolone acetonide-assisted pars plana vitrectomy (PPV).

METHODS

This prospective study included all consecutive patients admitted for surgical treatment of the epiretinal membrane (ERM) and macular hole (MH). The presence of complete PVD was determined one day before PPV using BM, US, SD-OCT. The preoperative findings were compared to the PVD status determined during PPV.

RESULTS

A total of 123 eyes from 123 patients were included in the study. Indications for PPV included ERM in 57 (46.3%), full thickness macular hole in 57 (46.3%) and lamellar macular hole in 9 (7.3%) patients. Complete PVD during PPV was observed in 18 (31.6%; 95%CI:18.7-49.9) patients with ERM and 13 (19.7%; 95%CI:10.4-33.7) patients with MH. The sensitivity of preoperative BM, US, SD-OCT was 48.4% (95%CI:30.2-66.9), 61.3% (95%CI:42.2-78.2) and 54.8% (95%CI:36.0-72.7) respectively. The specificity of preoperative BM, US, SD-OCT was 81.5% (95%CI:72.1-88.9), 90.2% (95%CI:82.2-95.4) and 85.9% (95%CI:77.0-92.3) respectively. With a prevalence of 25.2% of PVD in our sample the positive predictive value of preoperative BM, US, SD-OCT was 46.9% (95%CI:29.1-65.3), 67.9% (95%CI:47.6-84.1) and 56.7% (95%CI:37.4-74.5) respectively.

CONCLUSION

Preoperative BM, US, and SD-OCT showed relatively low sensitivity but also good specificity in assessing complete PVD. A combination of all three diagnostic methods can provide a good assessment of the vitreoretinal interface state.

Microinvasive pars plana vitrectomy combined with internal limiting membrane peeling versus anti-VEGF intravitreal injection for treatment-naïve diabetic macular edema (VVV-DME study): study protocol for a randomized controlled trial

BACKGROUND

Diabetic macular edema (DME) is the main cause of vision loss in diabetic patients. Currently, anti-vascular endothelial growth factor (VEGF) intravitreal injection stands as the first-line therapy for DME. However, some patients exhibit insufficient response to anti-VEGF agents and often require multiple injections, imposing psychological and economic burdens. While microinvasive pars plana vitrectomy (PPV) has been shown to be safe and effective in treating refractory DME, scant research has explored its application to treatment-naïve DME. The purpose of this study is to determine whether early PPV combined with internal limiting membrane (ILM) peeling can lessen the therapeutic burden of DME patients, prevent vision loss, and maintain long-term stabilization of diabetic retinopathy.

METHODS

This is a single-center, prospective, parallel-group, non-inferiority randomized controlled trial involving 102 DME participants. Participants will be randomly assigned to either the study group (PPV combined with ILM peeling) or the control group (conbercept intravitreal injection (IVC)) at a 1:1 ratio, with a scheduled follow-up at 12 months post-operation. Comparative analysis of results between the two groups will be conducted at months 1, 3, 6, and 12 after the intervention. The primary outcomes involve evaluating the changes in central subfield thickness (CST) and best corrected visual acuity (BCVA). The secondary outcomes include assessment of optical coherence tomography (OCT) and OCT angiography (OCTA) biomarkers, re-treatment and adverse events rates, diabetic retinopathy (DR) development, cost-effectiveness analysis, and vision-related quality of life (VRQL).

DISCUSSION

Some patients do not respond well to anti-VEGF drugs and repeated intravitreal injections increase the treatment burden for patients. The VVV study aims to explore whether PPV combined with ILM peeling could become an initial treatment option for treatment-naïve DME patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05728476. Registered on 15 February 2023.

Radiation retinopathy following episcleral brachytherapy for intraocular tumors: Current treatment options

Radiation retinopathy (RR) and radiation maculopathy (RM) can occur as a result of uveal melanoma radiation treatment and after irradiation of other head and neck extraocular tumors, even with precise targeting techniques, such as stereotactic or proton beam radiotherapy. This review provides an overview of the current understanding of potential radiation damage to ocular tissues, and how recent developments in ophthalmic multimodal imaging techniques and treatment modalities have improved managing options. Several treatment strategies have been employed so far for the management of RR, including laser photocoagulation, intravitreal injections of anti-vascular endothelial growth factor (VEGF) agents or glucocorticosteroids and surgery. The use of intravitreal anti-VEGFs or dexamethasone implants have significantly altered the final visual outcome for uveal melanoma patients. As a prophylaxis, a few different strategies were proposed, but still there is a lack of large randomized clinical trials supporting these approaches and clear clinical guidelines for daily practice. Early detection and proper treatment are crucial in preventing or reducing vision loss, and improving patients' quality of life. Close monitoring and timely intervention are essential for successful management.

Efficacy and safety of pan retinal photocoagulation combined with intravitreal anti-VEGF agents for high-risk proliferative diabetic retinopathy: A systematic review and meta-analysis

BACKGROUND

High-risk proliferative diabetic retinopathy (HR-PDR) is the advanced stage of diabetic retinopathy progression with poor prior treatment efficacy and high rates of blindness. This meta-analysis aims to compare the efficacy and safety of pan retinal photocoagulation (PRP) combined with intravitreal anti-vascular endothelial growth factor (aVEGF) (PRP + aVEGF) versus PRP monotherapy in HR-PDR patients.

METHODS

A thorough search was performed through PubMed, Web of Science, EMBASE, and the Cochran Library from inception to December 18, 2022. Outcome measures included change in central macular thickness, best-corrected visual acuity, fluorescein angiography, incidence of undergoing vitrectomy, and adverse events during the follow-up period.

RESULTS

Eight studies (6 randomized controlled trials and 2 retrospective studies) with 375 eyes were included in this meta-analysis. There were no obvious differences in the changes of best-corrected visual acuity and fluorescein angiography between the PRP + aVEGF and PRP monotherapy groups. However, PRP + aVEGF group had a significant reduction in the change of central macula thickness (standard mean deviations = -1.44, 95%CI = -2.55 to -0.32, P = .01) and the rate of undergoing vitrectomy (odds ratio = 0.20, 95%CI = 0.05-0.83, P = .01). Additionally, the risks of vitreous hemorrhage and other complications were not significantly different between the 2 groups.

CONCLUSION SUBSECTIONS

Our meta-analysis indicated that PRP + aVEGF might have potential benefits in the treatment of HR-PDR patients. However, given several limitations of this study, more research is needed to confirm our findings.

Update on current pharmacologic therapies for diabetic retinopathy

INTRODUCTION

Diabetic retinopathy is a major cause of visual loss worldwide. The most important clinical findings include diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR).

AREAS COVERED

PubMed was used for our literature review. Articles from 1995 to 2023 were included. Pharmacologic treatment of diabetic retinopathy generally involves the use of intravitreal anti-vascular endothelial growth factor (VEGF) therapy for DME and PDR. Corticosteroids remain important second-line therapies for patients with DME. Most emerging therapies focus on newly identified inflammatory mediators and biochemical signaling pathways involved in disease pathogenesis.

EXPERT OPINION

Emerging anti-VEGF modalities, integrin antagonists, and anti-inflammatory agents have the potential to improve outcomes with reduced treatment burdens.

TNFAIP8 overexpression aggravates retinal pathophysiological features of diabetic retinopathy

Our previous research shown that tumor necrosis factor-alpha-induced protein 8 (TNFAIP8) is elevated in the plasma extracellular vesicles and vitreous humor in diabetic retinopathy (DR). TNFAIP8 also significantly increases the viability of human retinal microvascular endothelial cells (HRMECs) and promotes cell migration and tube formation in vitro. To comprehensively explore its role in DR, we investigated the effect of TNFAIP8 on DR development using an animal model in this study. A TNFAIP8-overexpressing adeno-associated virus (AAV) vector and streptozotocin-induced mouse model was used. The AAV-TNFAIP8 vector was injected into the mice intravitreally, and the effect was evaluated. The evaluation included analysis of retinal structure and function using electroretinography, optical coherence tomography, and histological assessment. The influence of TNFAIP8 on the avascular area, retinal leukostasis, and the expression levels of inflammatory factors was also determined. TNFAIP8 significantly decreased a/b-wave amplitude and retinal thickness in diabetic mice. Histological assessment showed that TNFAIP8 aggravated pathological abnormalities with distorted organization of the retina. TNFAIP8 also significantly increased the avascular area, leukostasis, and the expression of inflammatory factors, such as TNFα, IL1β, ICAM1, and GFAP, in the retina. The results of this study support the role of TNFAIP8 in DR pathogenesis. A mechanistic understanding of TNFAIP8 may offer novel therapeutic strategies.

Objective perimetry identifies regional functional progression and recovery in mild Diabetic Macular Oedema

PURPOSE

Retinal function beyond foveal vision is not routinely examined in the clinical screening and management of diabetic retinopathy although growing evidence suggests it may precede structural changes. In this study we compare optical coherence tomography (OCT) based macular structure with function measured objectively with the ObjectiveFIELD Analyzer (OFA), and with Matrix perimetry. We did that longitudinally in Type 2 diabetes (T2D) patients with mild Diabetic Macular Oedema (DMO) with good vision and a similar number of T2D patients without DMO, to evaluate changes in retinal function more peripherally over the natural course of retinopathy.

METHODS

Both eyes of 16 T2D patients (65.0 ± 10.1, 10 females), 10 with baseline DMO, were followed for up longitudinally for 27 months providing 94 data sets. Vasculopathy was assessed by fundus photography. Retinopathy was graded using to Early Treatment of Diabetic Retinopathy Study (ETDRS) guidelines. Posterior-pole OCT quantified a 64-region/eye thickness grid. Retinal function was measured with 10-2 Matrix perimetry, and the FDA-cleared OFA. Two multifocal pupillographic objective perimetry (mfPOP) variants presented 44 stimuli/eye within either the central 30° or 60° of the visual field, providing sensitivities and delays for each test-region. OCT, Matrix and 30° OFA data were mapped to a common 44 region/eye grid allowing change over time to be compared at the same retinal regions.

RESULTS

In eyes that presented with DMO at baseline, mean retinal thickness reduced from 237 ± 25 μm to 234.2 ± 26.7 μm, while the initially non-DMO eyes significantly increased their mean thickness from 250.7 ± 24.4 μm to 255.7 ± 20.6 μm (both p<0.05). Eyes that reduced in retinal thickness over time recovered to more normal OFA sensitivities and delays (all p<0.021). Matrix perimetry quantified fewer regions that changed significantly over the 27 months, mostly presenting in the central 8 degrees.

CONCLUSIONS

Changes in retinal function measured by OFA possibly offer greater power to monitor DMO over time than Matrix perimetry data.

Intralenticular Ozurdex injection in an eye with thicker lens and the therapeutic effect maintained for 15 months

Introduction

To report a case of accidental intralenticular Ozurdex injection in an eye with thicker lens. During the follow-up period of 15 months, the therapeutic effect of intralenticular Ozurdex was maintained.

Case description

Ozurdex was accidently injected into the lens of an eye with uveitis, and the lens thickness was measured to be 5.70 mm. The uveitis was under good control, and no significant development of cataract was observed until 7 months after the intralenticular Ozurdex injection. Then due to the outbreak of COVID-19, follow-up was suspended. Fifteen months after the injection, the patient returned to the doctor. At this time, significant cataract development was observed, whereas uveitis was still under good control. Accordingly, cataract surgery and Ozurdex extraction were performed. Two months after surgery, a mild recurrence of uveitis occurred.

Conclusions

A thicker lens might be an important risk factor for accidental intralenticular Ozurdex injections. However, after intralenticular Ozurdex injection, the development of cataract was slow, and Ozurdex could still have a therapeutic effect on uveitis in this case. Thus, immediate surgery might be unnecessary for certain accidental intralenticular Ozurdex injection cases, and a follow-up strategy could be chosen to maintain the effect of Ozurdex.

Do new drugs for diabetic macular edema offer a safer option?

INTRODUCTION

The last decade has witnessed important advances in retinal drug discovery, administered intravitreally, allowing high intraocular concentration and low systemic passage. However, local and systemic adverse events have been described and should be discussed before proposing treatment. In diabetes mellitus specifically, the choice of molecule and treatment regimen should limit the therapeutic burden, avoiding the need for frequent ophthalmological appointments, in patients receiving multi-disciplinary care.

AREAS COVERED

We aim to review and discuss the risk/benefit ratio of the main intravitreal therapies currently proposed for diabetic macular edema (DME), and how these treatments could be tailored to each individual patient.

EXPERT OPINION

Anti-VEGF injections and steroid implants are currently the two therapeutic options proposed in cases of DME. New molecules in these two classes have recently been approved and are currently being studied under phase IV observations to establish their efficacy and tolerance. The preferred therapeutic option is determined based on the ocular condition and the patient profile. As new treatments are developed, new adverse events will also enter into consideration, and retinal physicians must therefore be able to call on a range of therapeutic options and question the risk/benefit ratio of each of them before proposing a treatment.

Upregulation of PCED1B-AS1 in proliferative diabetic retinopathy and its involvement in retinal vascular endothelial cell proliferation

BACKGROUND

This study was to assess the diagnostic value of PCED1B-AS1 for proliferative diabetic retinopathy (PDR) and investigate the involvement of PCED1B-AS1 in PDR.

METHODS

The vitreous and blood specimens from 37 subjects with PDR and 21 non-diabetics were examined by reverse transcription quantitative PCR to determine the PCED1B-AS1 level. The two groups were age- and gender-matched. Receiver operating characteristic (ROC) curves were plotted to visually illustrate the diagnostic ability of PCED1B-AS1. Human retinal Müller glial cells were studied by ELISA. Proliferation and migration of human retinal microvascular endothelial cells (HRMECs) were assessed in vitro.

RESULTS

Significant increases of PCED1B-AS1 levels were observed in the vitreous samples and CD34 + VEGFR-2 + cells from blood samples of diabetic subjects with PDR, compared with those of non-diabetics. The ROC curve based on the vitreous PCED1B-AS1 levels revealed an AUC of 0.812, while the ROC curve based on the PCED1B-AS1 levels in CD34 + VEGFR-2 + cells from blood samples revealed an AUC of 0.870. In Müller cell cultures, PCED1B-AS1 siRNA significantly attenuated VEGF and MCP-1 upregulation which were induced by CoCl₂ and TNF-α. Additionally, PCED1B-AS1 siRNA attenuated VEGF-induced proliferation and migration in HRMECs.

CONCLUSION

This study revealed the potential of PCED1B-AS1 as a diagnostic biomarker for PDR. In vitro data point to the anti-angiogenic and anti-proliferation effects of PCED1B-AS1.

Metformin therapy as a strategy to compensate anti-VEGF resistance in patients with diabetic macular edema

Diabetic macular edema (DME) is the complication of diabetic retinopathy, the leading cause of vision loss among diabetic patients. Metformin is the main antidiabetic treatment. It is preferable for its great anti-angiogenic and anti-inflammatory effects. Anti-vascular endothelial growth factor (VEGF) therapy is the preferable treatment for DME despite its lack of convincing results in some patients. To assess whether the combination of metformin and anti-VEGF drugs may decrease the risk of anti-VEGF resistance among DME patients. We included DME patients with a central retinal thickness (CRT) ≥ 250 μm who consecutively underwent at least 3 anti-VEGF therapies from January 1, 2020, to December 30, 2021. Anti-VEGF resistance was defined as persistent macular edema with decreased CRT ≤ 25% after 3 anti-VEGF injections. 109 patients were considered for this research, of whom 65 (59.6%) were resistant to anti-VEGF therapy. The mean CRT of the non-metformin group decreased from 344.88 ± 129.48 to 318.29 ± 123.23 (20.85%) and from 415.64 ± 144.26 to 277.11 ± 99.25 (31.51%) (P = .031) in the metformin group. Moreover, the metformin group had fewer resistant patients than the non-metformin, 24 (45.3%) versus 41 (73.2%). Furthermore, a considerable gain in visual acuity was observed in both groups, with a BCVA gain of 40.41% in the metformin group and 39.9% in the non-metformin group. Metformin may be combined with an anti-VEGF drug to minimize the risk of anti-VEGF resistance among DME patients. Moreover, it can serve to design effective therapeutic deliveries.

Aflibercept versus Faricimab in the Treatment of Neovascular Age-Related Macular Degeneration and Diabetic Macular Edema: A Review

Diabetic macular edema (DME) and neovascular age-related macular degeneration (nAMD) are common retinal vascular diseases responsible for most blindness in the working-age and older population in developed countries. Currently, anti-VEGF agents that block VEGF family ligands, including ranibizumab, bevacizumab (off-label use), brolucizumab, and aflibercept, are the first-line treatment for nAMD and DME. However, due to the complex pathophysiological background of nAMD and DME, non-response, resistance during anti-VEGF therapy, and relapses of the disease are still observed. Moreover, frequent injections are a psychological and economic burden for patients, leading to inadequate adhesion to therapy and a higher risk of complications. Therefore, therapeutic methods are strongly needed to develop and improve, allowing for more satisfactory disease management and lower treatment burden. Currently, the Ang/Tie-2 pathway is a promising therapeutic target for retinal vascular diseases. Faricimab is the first bispecific monoclonal antibody for intravitreal use that can neutralize VEGF and Ang-2. Due to the prolonged activity, faricimab allows extending the interval between successive injections up to three or four months in nAMD and DME patients, which can be a significant benefit for patients and an alternative to implanted drug delivery systems.

Association of metformin treatment with enhanced effect of anti-VEGF agents in diabetic macular edema patients

PURPOSE

To investigate the effect of metformin combined with anti-VEGF agents in patients with diabetic macular edema (DME).

METHODS

This study was a prospective, nonrandomized case-control study. Patients were included in with a diagnosis of DME who received anti-VEGF agents injection. Basic information, medical history, best-corrected visual acuity (BCVA), central macular thickness (CMT), the number of intravitreal injections, panretinal photocoagulation (PRP), and macular grid photocoagulation treatment during the 6-month follow-up, were recorded for each patient.

RESULTS

A total of 50 DME patients were collected (24 patients with a history of oral metformin ≥ 6 months and 26 patients who had not taken metformin). The BCVA and the CMT were significantly improved after anti-VEGF treatment in two groups (F1 = 19.35, F2 = 26.78; F1 = 65.45, F2 = 76.23; P < 0.05). The BCVA in the metformin group was better than that in non-metformin group at every point after treatment (F = 34.45, P < 0.05). The CMT in metformin group decreased much more than that in non-metformin group during the follow-up period (F = 87.05, P < 0.05). The injection numbers decreased in the metformin group compared with the non-metformin group (t = 5.14, P < 0.05). However, there was no difference in PRP and macular grid photocoagulation therapy between the two groups during the 6-month follow-up.

CONCLUSION

Metformin can enhance the therapeutic effect of anti-VEGF agents on DME patients to improve their visual acuity, improve the structure of the macular area, and reduce the number of intravitreal injections 90.

Intraprocedural OCT monitoring of the immediate treatment response during indocyanine green angiography-guided laser therapy of teleangiectatic capillaries in diabetic macular edema

In this retrospective study the morphological response of teleangiectatic capillaries (TCs) to focal laser treatment and the functional and morphological outcome after Indocyanine green angiography (ICGA)-guided laser therapy was evaluated. TCs in eyes with diabetic macular edema (DME) were treated with laser therapy. The immediate and subsequent reaction of the TCs lumina to direct photocoagulation was monitored with customized OCT single scans. Additionally, patients were treated with intravitreal anti-VEGF as needed. 12 eyes of 9 patients with treatment naive (6 eyes) and pretreated (6 eyes) DME were followed-up for a mean of 24 months (± 8.1SD). Best-corrected visual acuity improved from 0.25 logMar (± 0.2SD) to 0.12 (± 0.10SD; p = 0.06) at each patient’s last visit. During laser treatment a darkening of the TCs lumina was achieved in 91.3% of lesions. All these lesions fully resolved, whereas TCs, which showed no darkening of their lumen in OCT persisted and required re-treatment with laser. Additional anti-VEGF injections were indicated in only one eye (8.3%). The darkening of the TCs lumina visible in OCT might provide an image-biomarker that indicates successful coagulation of aneurysmatic lesions. Consequently, a significant functional and morphological improvement with need for anti-VEGF treatment in only one eye, was achieved.

Information concerning the registration of the trial: date of registration: 11th of december, 2019. Trial registration number: 107/2019.

Prediction of Visual Acuity after anti-VEGF Therapy in Diabetic Macular Edema by Machine Learning

PURPOSE

To predict visual acuity (VA) 1 month after anti-vascular endothelial growth factor (VEGF) therapy in patients with diabetic macular edema (DME) by using machine learning.

METHODS

This retrospective study included 281 eyes with DME receiving intravitreal anti-VEGF treatment from January 1, 2019, to April 1, 2021. Eighteen features from electronic medical records and measurements data from OCT images were extracted. The data obtained from January 1, 2019, to November 1, 2020, were used as the training set; the data obtained from November 1, 2020, to April 1, 2021, were used as the validation set. Six different machine learning algorithms were used to predict VA in patients after anti-VEGF therapy. After the initial detailed investigation, we designed an optimization model for convenient application. The VA predicted by machine learning was compared with the ground truth.

RESULTS

The ensemble algorithm (linear regression + random forest regressor) performed best in VA and VA variance predictions. In the validation set, the mean absolute errors (MAEs) of VA predictions were 0.137-0.153 logMAR (within 7-8 letters), and the mean square errors (MSEs) were 0.033-0.045 logMAR (within 2-3 letters) for the 1-month VA predictions, respectively. For the prediction of VA variance at 1 month, the MAEs were 0.164-0.169 logMAR (within 9 letters), and the MSEs were 0.056-0.059 logMAR (within 3 letters), respectively.

CONCLUSIONS

Our machine learning models could accurately predict VA and VA variance in DME patients receiving anti-VEGF therapy 1 month after, which would be much valuable to guide precise individualized interventions and manage expectations in clinical practice.

A comparison between the therapeutic effects of Conbercept combined with panretinal photocoagulation and panretinal photocoagulation monotherapy for high-risk proliferative diabetic retinopathy

OBJECTIVE

To compare the therapeutic effects of the administration of intravitreal Conbercept (IVC) plus panretinal photocoagulation (PRP) to that of PRP monotherapy in patients with high-risk proliferative diabetic retinopathy (PDR).

METHODS

In this retrospective consecutive case series, we analyzed the data on high-risk PDR patients followed up for 12 months. Patients were divided into two groups: the IVC+PRP group and the PRP monotherapy group. Patients in the IVC+PRP group were initially administered 3 IVC injections and PRP, while patients in the PRP monotherapy group received PRP only. Depending on the grouping criteria, patients in both groups were administered either IVC+PRP or PRP only if the neovascularization (NV) did not regress. From the initiation to month 12 of treatment, we recorded and compared the data on the NV regression rate, improvement in best-corrected visual acuity (BCVA), laser spots, changes in central macular thickness (CMT), complications, and the need for vitrectomy for all patients.

RESULTS

In this study, 79 eyes of 58 patients in the IVC+PRP group and 86 eyes of 60 patients in the PRP monotherapy group were included. During the follow-up of 12 months, the number of eyes with complete regression, partial regression, and no regression or increase in NV were 56 (70.88%), 23 (29.12%), and 0 (0%) in the IVC+PRP group and 13 (15.12%), 50 (58.14%), and 23 (26.74%) in the PRP group (p < 0.001). The BCVA was significantly higher and CMT was lower in the patients of the IVC+PRP group than in the PRP monotherapy group at 3, 6, and 12 months of follow-up (p < 0.05). The mean number of laser spots was lower in the patients of the IVC+PRP group than in the PRP group (1,453 ± 87 spots vs. 2,267 ± 94 spots, p < 0.05). A significantly lower percentage of patients in the IVC+PRP group underwent vitrectomy than that in the PRP group (7 (8.86%) vs. 27 (31.40%), p < 0.001).

CONCLUSION

High-risk PDR patients treated with IVC + PRP showed a higher rate of NV regression, more effective improvement in the BCVA, and lower vitrectomy rate compared to those who were administered PRP monotherapy.

Feasibility of Therapeutic Ultrasound Application in Topical Scleral Delivery of Avastin

Purpose

Macromolecules have been shown to be effective in vision-saving treatments for various ocular diseases, such as age-related macular degeneration and diabetic retinopathy. The current delivery of macromolecules requires frequent intraocular injections and carries a risk of serious adverse effects.

Methods

We tested the application of therapeutic ultrasound as a minimally invasive approach for the delivery of Avastin into the diseased regions of the eye. Avastin (bevacizumab) is an anti-vascular endothelial growth factor (VEGF) antibody with a molecular weight of 149 kDa. We tested the effectiveness and safety of Avastin delivery through rabbit sclera in vitro using a standard diffusion cell model. Ultrasound at frequencies of 400 kHz or 3 MHz with an intensity of 1 W/cm2 was applied for the first 5 minutes of 1-hour drug exposure. Sham treatments mimicked the ultrasound treatments, but ultrasound was not turned on. Absorbance measurements of the receiver compartment solution were performed at 280 nm using a spectrophotometer.

Results

Absorbance measurements indicated no statistical difference between the sham (n = 13) and 400 kHz ultrasound group (n = 15) in the delivery of Avastin through the sclera. However, the absorbance values were statistically different (P < 0.01) between the 3 MHz ultrasound group (0.004, n = 8) and the matched sham group (0.002, n = 7). There was 2.3 times increase in drug delivery in the 3 MHz ultrasound when compared to the corresponding sham group. Histological studies indicated no significant damage in the ultrasound-treated sclera due to ultrasound application.

Conclusions

Our preliminary results provided support that therapeutic ultrasound may be effective in the delivery of Avastin through the sclera.

Translational Relevance

Our study offers clinical potential for a minimally invasive retinopathy treatment.