NEW INSIGHTS IN RESISTANT DIABETIC MACULAR EDEMA

Diabetic macular edema (DME): dissecting pathogenesis, prognostication, diagnostic modalities along with current and futuristic therapeutic insights

One of the most common health concerns disturbing people within working years globally is diabetes mellitus (DM). One well-known consequence of DM is vascular damage, which can manifest as macro- and microangiopathy affecting the ocular retina. Therefore, Diabetic macular edema (DME) is a major sight-threatening complication of diabetic retinopathy (DR) worldwide. It is the most prevalent cause of significant vision impairment in diabetic patients. Long-term vision loss can be avoided by following early DME treatment guidelines in everyday life. Hence, there are various therapeutic approaches for DME management. Currently, the first-line treatment for DME is anti-VEGF family drugs, such as ranibizumab, brolucizumab, bevacizumab, and aflibercept. Nevertheless, relapses of the disease, inadequate response, and resistance during anti-VEGF therapy are still seen because of the intricate pathophysiological foundation of the disease. Consequently, there is an excellent requirement for therapeutic approaches to advance and become better at controlling diseases more satisfactorily and require fewer treatments overall. We conducted a thorough literature search in the current review to present a comprehensive overview of the primary data about the current DME therapeutic agents. We also covered the novel advances in DME management and probable future treatments being investigated and developed. This review recommended that Large clinical trials should afford sufficient evidence to support these innovative treatment modalities.

Comprehensive assessment of the impact of intravitreal faricimab on retinal diseases: A systematic review, meta-analysis, and trial sequential analysis

BACKGROUND

Faricimab stands as the inaugural and sole bispecific antibody approved by the US Food and Drug Administration (FDA) for intravitreal injection. Nonetheless, the efficacy and safety of intravitreal faricimab remained uncertain.

OBJECTIVES

The purpose of this study was to evaluate faricimab.

METHODS

This systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (CRD42023398320). Five databases (Pubmed, Embase, Web of science, Cochrane Library, ClinicalTrials gov) were searched. We calculated pooled standard mean difference or odds ratio with 95 % confident interval under a random-effect model or fixed-effect model. Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) was employed to ascertain the reliability of the analyses. Trial sequential analysis was performed to gauge the statistical reliability of the data in the cumulative meta-analysis.

RESULTS

8 studies (3975 participants) were included. The use of faricimab was associated with central subfield thickness (CST) change, but no difference was found in other primary efficacy outcomes. Apart from that, a correlation was observed between the use of faricimab and the risk of vitreous floaters. Based on TSA, strong evidence indicates that compared to the control group, faricimab aided in reducing CST but increasing the risk of vitreous floaters.

CONCLUSIONS

In this study, a correlation existed between the use of faricimab and a reduction in CST, indicating a superior therapeutic effect. Moreover, participants treated with faricimab demonstrated a higher risk of vitreous floaters. More randomized controlled trials are essential to further explore the efficacy and safety of faricimab.

Identification and mechanistic analysis of neurovascular coupling related biomarkers for diabetic macular edema

Introduction

Diabetic macular edema (DME) is a major cause of vision loss in the sick with diabetic retinopathy. The occurrence of DME is closely related to the breakdown of neurovascular coupling; however, its underlying mechanism has not been fully elucidated. The aim of this study was to investigate the diagnostic biomarkers and potential molecular mechanisms associated with neurovascular coupling in DME.

Methods

The differential expression analysis, STEM, and WGCNA were performed from GSE160306 to identify hub genes. The gene expression was validated by RT-qPCR. The relevant mechanisms of action were investigated through GO, KEGG, and GSEA analyses, as well as co-expression networks. Additionally, the LASSO regression analysis and a nomogram were used to demonstrate the diagnostic effectiveness of the model. Finally, the GenDoma platform was utilized to identify drugs with potential therapeutic effects on DME.

Results

Neurotrophic factor receptor (NGFR) was identified as a hub gene related to neurovascular coupling and DME. The expression of NGFR was verified by RT-qPCR in vitro cells. GSEA analysis indicated that high expression of NGFR may affect immunity and inflammatory pathway, thereby regulating neurovascular coupling and mediating the development of DME. The NGFR co-expression network was constructed, which exhibited the correlation with the neurotrophin signaling pathway. Moreover, a diagnostic model for DME based on NGFR and PREX1 demonstrated relatively good diagnostic performance using LASSO regression analysis and the nomogram. And then the GenDoma platform identified drugs with potential therapeutic effects on DME.

Conclusion

The high expression of NGFR may lead to abnormal neurovascular coupling and participate in the occurrence of DME by regulating the immunity, inflammatory and neurotrophin signaling pathway. Detection of NGFR and related expression genes may be beneficial for monitoring the occurrence and development of DME.

EPIRETINAL MACROPHAGE-LIKE CELLS ON OPTICAL COHERENCE TOMOGRAPHY: Potential Inflammatory Imaging Biomarker of Severity in Diabetic Retinopathy

PURPOSE

To investigate the clinical value of epiretinal macrophage-like cells (eMLCs) in different stages of diabetic retinopathy (DR), including diabetic macular edema (DME).

METHODS

One hundred and seventy-six eyes of 176 patients, including 31 diabetes eyes without retinopathy, 24 with mild nonproliferative DR (NPDR), 37 with moderate NPDR, 32 with severe NPDR, and 52 with proliferative DR, were compared with 30 healthy controls. The optic nerve head and macular region were examined using en face optical coherence tomography and optical coherence tomography angiography. A previously described technique was employed to measure the eMLCs on the inner limiting membrane.

RESULTS

The optic nerve head and macular eMLC densities increased with worsening DR stage and were higher in moderate, severe NPDR, and proliferative DR, especially in eyes with DME (all adjusted P < 0.01). The optic nerve head and macular eMLC densities in the DME groups were higher than those in their corresponding non-DME groups at the same DR stage (all P < 0.05). The average macular thickness was correlated with macular eMLC density (standardized β = 0.661, P < 0.001) in patients with diabetes. The proportion of eyes with larger and plumper eMLCs increased with worsening DR and was higher in moderate, severe NPDR, proliferative DR, and eyes with DME ( P = 0.018, P < 0.001, P < 0.001, and P < 0.001, respectively).

CONCLUSION

Increased density along with morphological changes of eMLCs is observed beginning with moderate NPDR and correlates with the progression of DR, including DME.

Biophysics of ophthalmic medications during spaceflight: Principles of ocular fluid dynamics and pharmacokinetics in microgravity

As spaceflight becomes increasingly accessible and expansive to humanity, it is becoming ever more essential to consider the treatment of various eye diseases in these challenging environments. This paper delves into the increasing fascination with interplanetary travel and its implications for health management in varying environments. It specifically discusses the pharmacological management of ocular diseases, focusing on two key delivery methods: topical eye drops and intravitreal injections. The paper explores how microgravity impacts the administration of these treatments, a vital aspect in understanding drug delivery in space. An extensive analysis is presented on the pharmacokinetics of eye medications, examining the interaction between pharmaceuticals and ocular tissues in zero gravity. The goal of the paper is to bridge the understanding of fluid dynamics, microgravity and the human physiological systems to pave the way for innovative solutions faced by individuals in microgravity.

Aqueous humour interleukin-6 and vision outcomes with anti-vascular endothelial growth factor therapy

BACKGROUND

This analysis evaluated aqueous humour (AH) interleukin (IL)-6 concentrations and the association between AH IL-6 and visual outcomes in patients with neovascular age-related macular degeneration (nAMD) or diabetic macular oedema (DMO) receiving anti-vascular endothelial growth factor (VEGF) monotherapy.

METHODS

Post hoc analysis of the multicentre, double-masked, randomised HARBOR (NCT00891735) and READ-3 (NCT01077401) trials. HARBOR enrolled treatment-naïve nAMD patients. READ-3 enrolled treatment-naïve/previously treated DMO patients. HARBOR patients received ranibizumab 0.5 or 2.0 mg monthly or as needed; AH samples were collected at month 2, after two previous intravitreal injections. READ-3 patients received ranibizumab 0.5 or 2.0 mg as needed; AH samples were collected at baseline and months 3, 6, 9, and 12.

MAIN OUTCOME MEASURE

association between AH IL-6 concentrations and month 24 best-corrected visual acuity (BCVA).

RESULTS

In both trials (HARBOR, N = 36; READ-3, N = 137), patients with higher AH IL-6 concentrations had worse visual outcomes. HARBOR patients with low AH IL-6 concentrations at month 2 had a mean (95% CI) BCVA change at month 24 of +2.9 (-2.6, 8.3) letters, whereas patients with high AH concentrations had a mean (95% CI) BCVA change of -9.0 (-22.7, 4.7) letters. READ-3 patients with low AH concentrations at baseline had a mean (95% CI) BCVA change at month 12 of +9.3 (7.4, 11.3) letters, whereas patients with high AH concentrations had a mean (95% CI) BCVA change of +5.6 (2.2, 9.1) letters.

CONCLUSIONS

Higher IL-6 AH concentrations may predict suboptimal visual responses to anti-VEGF monotherapy in patients with nAMD/DMO.

Anti-VEGF and steroid combination therapy relative to anti-VEGF mono therapy for the treatment of refractory DME: A systematic review of efficacy and meta-analysis of safety

The aim of the study was to determine the efficacy and safety of combined anti-VEGF and steroid therapy in treatment refractory DME patients. We conducted a systematic review and meta-analysis of peer-reviewed articles reporting on visual, anatomical and adverse outcomes to compare the efficacy and safety of combined intravitreal anti-VEGF/steroids versus anti-VEGF monotherapy for refractory DME. Seven studies (4 RCTs and 3 observational studies) reporting on 452 eyes were included. Our systematic review showed that combination therapy is significantly more effective for anatomical outcomes in the treatment of resistant DME compared to anti-VEGF monotherapy in six studies. Two studies found that addition of intravitreal steroids promoted faster visual improvement, but not significantly better final visual outcomes compared to anti-VEGF monotherapy. Combination therapy was associated with a higher incidence of IOP-related adverse events (RR = 0.10, 95% CI = [0.02, 0.42], p = 0.002) and cataract-related adverse events (RR = 0.10, 95% CI = [0.01, 0.71], p = 0.02). Our systematic review and meta-analysis of seven studies and 452 eyes revealed that combination therapy of anti-VEGF and steroid intravitreal drugs in the management of treatment refractory DME resulted in superior anatomical outcomes in all but one study. Combination therapy led to superior short-term visual outcomes in two studies, while others reported no difference between treatment groups. Meta-analysis revealed that combination therapy was associated with more adverse events. Future research should provide guidance on the standard definitions for treatment resistance and therapeutic alternatives for DME patients with sub-optimal response to anti-VEGF treatment.

Comparison between intravitreal brolucizumab and aflibercept in the treatment-naive central involved diabetic macular edema: One-year real-life case series

PURPOSE

To evaluate the effectiveness and safety of intravitreal brolucizumab (IVB) and intravitreal aflibercept (IVA) injections in the management of naive central involved diabetic macular edema (CIDME).

METHODS

This study included 45 treatment-naive eyes with CIDME. A complete ophthalmic examination, including BCVA and SD-OCT was performed. Patients were randomized to (IVB) or (IVA) groups. All participants received a loading phase of three consecutive intravitreal injections, then followed by a personalized treat and extend (T&E) regimen.

RESULTS

At 12-month follow-up, the mean numbers of injections in IVA and IVB groups were 7.25  ±  0.53 and 6.3  ±  0.45, respectively (P < 0.0001). The IVA group showed a significant increase of the mean BCVA from 0.66  ±  0.15 logMAR (50.9  ±  7.7 letters) to 0.41  ±  0.19 logMAR (63.7  ±  10.8 letters). Mean CFT decreased significantly from 441.2  ±  35.7 μm to 281.3  ±  18.4 μm. The IVB group showed a significant increase of mean BCVA from 0.65  ±  0.16 logMAR (52.1  ±  7.9 letters) to 0.39  ±  0.17 logMAR (65.3  ±  8.7 letters). Mean CFT decreased significantly from 437.2  ±  41.9 μm to 275.5  ±  21.7 μm.No significant difference between both groups in terms of the vision improvement and the reduction of CFT was reported, whereas a statistical difference was observed in terms of intravitreal injections (IVI) numbers. No ocular complications were reported.

CONCLUSIONS

This case series highlights the effectiveness of both brolucizumab and aflibercept in the treatment of CIDME with a lower frequency of injection in brolucizumab group lowering the burden of IVI in this cohort.

Worsening of early DME after cataract surgery. The DICAT II Study report #2

PURPOSE

To analyse the long anatomical and functional outcome of a subgroup of the DICAT II study cohort, consisting of 26 patients undergoing cataract surgery and withdrawn from the study for a clinically significant worsening of early diabetic macular edema (DME).

MATERIALS

Patients who underwent cataract surgery and withdrawn from the DICAT II study for a clinically significant worsening of early DME with at least 12 months follow-up after the dropout. The study population was divided into two groups according to the clinical evaluation at one-year follow-up: ongoing treatment patients for DME (Treatment group, TG) and patients no longer treated (Non Treatment group, NTG).

RESULTS

Central foveal thickness (CFT) at baseline and dropout time were higher in TG than in the NTG, with a statistically significant difference (p < 0.05). In addition, TG patients reported a higher levels of glycated hemoglobin at time baseline compared to NTG patients (7.81 ± 1.15 vs 7.02 ± 0.56; p = 0.048). The linear regression analysis demonstrated a statistically significant relationship between the visual acuity and the ongoing treatment group at one-year follow-up (p = 0.042).

CONCLUSION

The study provides parameters to be considered when assessing the risk of developing persistent DME after cataract surgery in diabetic patients. In particular, CFT at baseline and dropout time have been reported to be an effective and predictable OCT biomarkers when evaluating DME progression. During the evaluation of the systemic disease, similar results were found for the glycated hemoglobin at baseline.

Intravitreal OZURDEX vs. Intravitreal Bevacizumab for Diabetic Macular Edema: A Comprehensive Review

This comprehensive review examines the efficacy, safety, and implications of intravitreal OZURDEX and intravitreal bevacizumab in treating diabetic macular edema (DME). DME is a common complication of diabetes mellitus and a leading cause of vision loss. OZURDEX, through sustained release of dexamethasone, targets inflammation and vascular permeability, while bevacizumab inhibits vascular endothelial growth factor (VEGF), reducing angiogenesis. However, differences in safety profiles exist, with OZURDEX associated with an increased risk of intraocular pressure elevation and cataract formation and bevacizumab potentially carrying systemic risks. The choice between these treatments should be individualized, considering patient preferences, ocular and systemic comorbidities, and cost-effectiveness. Collaboration among healthcare providers is essential for the comprehensive management of DME. Future research should focus on long-term comparative studies, predictors of treatment response, and exploration of novel therapeutic targets to optimize treatment outcomes for patients with DME.

Diabetic Macular Edema Management: A Review of Anti-Vascular Endothelial Growth Factor (VEGF) Therapies

Diabetic macular edema (DME) is a major cause of vision impairment in diabetic individuals, characterized by fluid accumulation in the macula due to a breakdown of the blood-retinal barrier (BRB). This review article explores the role of anti-vascular endothelial growth factor (anti-VEGF) therapies in the management of DME. Anti-VEGF treatments, including ranibizumab, bevacizumab, and aflibercept, have revolutionized DME management by targeting VEGF, a key mediator in DME pathogenesis. We critically examined the efficacy of these therapies in reducing macular edema and improving visual acuity, assessed their safety and tolerability, and explored the variability in treatment response. The review highlights the latest advancements and future directions in anti-VEGF therapy, including novel drug delivery systems and emerging treatment paradigms. By providing a comprehensive overview of current anti-VEGF therapies, this review seeks to inform clinical practice, guide future research, and contribute to improved patient outcomes in DME management.

Early effects of intravitreal anti-VEGF agents on cornea and visual acuity in patients with diabetic retinopathy

PURPOSE

This study aimed to investigate the early effects of intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents on the cornea and visual acuity in patients with diabetic retinopathy (DR).

METHODS

This retrospective study enrolled patients who were administered conbercept or ranibizumab to treat DR. Fundus photograph, fluorescein angiograph, and optical coherence tomography were preoperatively performed. The patients were classified into two groups: nonproliferative DR (NPDR) and PDR. Best-corrected visual acuity (BCVA), specular microscopy, central corneal thickness (CCT), and intraocular pressure were obtained before injection and at 1 day and 7 days after injection. The effects of anti-VEGF agents on BCVA and CCT were compared between the groups receiving conbercept and ranibizumab and between NPDR and PDR eyes.

RESULTS

A total 38 eyes (30 patients) were enrolled in this study. Twenty-one eyes received conbercept, and 17 eyes received ranibizumab. Twenty eyes were classified as NPDR and 18 eyes as PDR. No significant differences were found between the groups receiving conbercept and ranibizumab in the increase in BCVA nor in the increase of CCT at 1 day and 7 days after injection. As compared with NPDR eyes, PDR eyes demonstrated a significantly greater increase in CCT (-5.3 ± 3.7 vs. 6.5 ± 2.9 μm, P = 0.02 < 0.05) but not in BCVA (P = 0.33) at 1 day after injection. At 7 days after injection, no significant differences were found in the increase in BCVA nor in the increase of CCT between NPDR eyes and PDR eyes.

CONCLUSION

Intravitreal administration of anti-VEGF agents could cause a small but significant greater increase in CCT in PDR than in NPDR eyes in the early period. In patients with DR, no significant difference was found between conbercept and ranibizumab in the early effects on the visual acuity nor in the cornea.

Study of aqueous humour inflammatory mediators' levels in a cohort of Egyptian patients with diabetic macular oedema

BACKGROUND

The aim was to study aqueous humour inflammatory mediators' levels in a cohort of Egyptian patients with diabetic macular oedema (DMO).

METHODS

This was a case-control prospective study conducted on 2 groups: 25 eyes of 22 (11 females) patients seeking treatment for DMO as patients group, and 10 eyes of 10 (4 females) cataract patients as a control group. Aqueous humour was aspirated before intravitreal injection (patients' group) or cataract surgery (control group). Inflammatory mediators in aqueous humour were measured using a multiplex bead immunoassay kit of 27 pre-mixed cytokines.

RESULTS

Eotaxin, interferon gamma-induced protein 10 (IP-10), monocyte chemoattractant protein-1 (MCP-1/CCL2) and interleukin-8 (IL-8/CXCL8) were found significantly higher in patients' group compared to control group (p = 0.043, 0.037, 0.001, 0.015 respectively). On the contrary, interferon-gamma (IFN-gamma) and granulocyte colony-stimulating factor (G-CSF) were found significantly higher in control group than patients' group (p = 0.003, 0.019 respectively). Basic fibroblast growth factor (Basic-FGF/FGF-2) and interleukin-1 receptor antagonist (IL-1ra) were found higher (but not statistically significant) in controls (p = 0.100 and 0.070 respectively). Additionally, a negative and significant correlation was found between Eotaxin level in aqueous humour and central macular thickness.

CONCLUSIONS

Some mediators might be implicated in the pathogenesis of DMO either augmenting or suppressing role. Eotaxin, IP-10, MCP-1 and IL-8 might have a role in cases not responding to standard anti-vascular endothelial growth factor (VEGF) therapy. IL-1ra might have a protective role; therefore, the effectiveness of intravitreal injection of IL-1ra homologue needs to be studied in future clinical trials.

The Role of Laser Photocoagulation in Treating Diabetic Macular Edema in the Era of Intravitreal Drug Administration: A Descriptive Review

Background and Objectives: This study aimed to elucidate the role of laser photocoagulation therapy in the treatment of diabetic macular edema (DME) as an alternative to, or in conjunction with, the first-line treatment, anti-vascular endothelial growth factor (VEGF). Materials and Methods: A comprehensive literature search to identify studies that evaluated the efficacy of laser photocoagulation therapy in the management of DME was performed. The relevant findings of the efficacy of focal/grid laser therapy from data in randomized, controlled trials were synthesized, and the potential of new laser technologies, such as navigated laser systems, pattern scan lasers, and subthreshold lasers, was explored. The usefulness of multimodal imaging-guided laser therapy was also evaluated, with a focus on the potential contribution to anti-VEGF therapy. Results: Focal laser photocoagulation targeting microaneurysms remains an effective therapeutic approach to chronic refractory edema, despite the widespread use of anti-VEGF therapy. To achieve the best possible treatment outcomes, precise identification of microaneurysms is essential. This requires the use of multimodal imaging-guided, highly accurate, minimally invasive coagulation techniques. Subthreshold laser therapy can also reduce the frequency of anti-VEGF injections and minimize treatment burden. Conclusions: Further studies are needed to determine the optimal timing and settings for laser photocoagulation therapy and the potential of new laser technologies in the management of DME. Nevertheless, laser photocoagulation therapy plays an important role in the management of DME, in conjunction with anti-VEGF therapy.

Characteristics and Treatment Patterns of Patients with Diabetic Macular Edema Non-Responsive to Anti-Vascular Endothelial Growth Factor Treatment in Ontario, Canada

Purpose

To understand the demographics, clinical characteristics, treatment patterns, visual and anatomic responses of patients with diabetic macular edema (DME) initially treated with anti-vascular endothelial growth factor (anti-VEGF) agents in the real-world clinical setting.

Patients and Methods

This retrospective cohort study used electronic health records to identify consecutively presenting patients with DME who received their first documented anti-VEGF injection (index injection) on or after 1 October 2015 and before 30 September 2016 (index period) at 4 clinical sites in Ontario, Canada. Patients receiving anti-VEGF injections in the study eye were followed for ≥18 months. After the first 3 monthly injections, patients were classified as "responder" (≥20% reduction in central retinal thickness [CRT] from index date) or "nonresponder" (<20% reduction in CRT) to anti-VEGF treatment.

Results

At 12 months, change from baseline (CFB) in best visual acuity (BVA) of responders (n = 30) was mean (SD) 12.8 (13.00) letters; CFB in nonresponders (n = 56) was 3.2 (16.3) letters. Sensitivity analyses stratified by initial BVA were supportive. Mean (SD) change in CRT (μm) was -160.4 (111.4) in responders and -62.2 (98.6) in nonresponders. While changes in anti-VEGF therapy were lower in responders versus nonresponders (10.0% vs 23.2%), mean number of injections was similar (8.3 in each cohort).

Conclusion

Despite receiving a substantial number of injections and requiring changes in therapy more frequently, nonresponders showed a lack of clinically meaningful change in BVA and CRT. Nonresponders could be identified after 3 anti-VEGF injections. There remains an unmet need for treatment options in patients with DME who show a nonresponse after 3 months of anti-VEGF treatment.

MicroRNA 9 Is a Regulator of Endothelial to Mesenchymal Transition in Diabetic Retinopathy

Purpose

Diabetic retinopathy (DR) is a significant cause of blindness. Most research around DR focus on late-stage developments rather than early changes such as early endothelial dysfunction. Endothelial-to-mesenchymal transition (EndMT), an epigenetically regulated process whereby endothelial cells lose endothelial characteristics and adopt mesenchymal-like phenotypes, contributes to early endothelial changes in DR. The epigenetic regulator microRNA 9 (miR-9) is suppressed in the eyes during DR. MiR-9 plays a role in various diseases and regulates EndMT-related processes in other organs. We investigated the role miR-9 plays in glucose-induced EndMT in DR.

Methods

We examined the effects of glucose on miR-9 and EndMT using human retinal endothelial cells (HRECs). We then used HRECs and an endothelial-specific miR-9 transgenic mouse line to investigate the effect of miR-9 on glucose-induced EndMT. Finally, we used HRECs to probe the mechanisms through which miR-9 may regulate EndMT.

Results

We found that miR-9 inhibition was both necessary and sufficient for glucose-induced EndMT. Overexpression of miR-9 prevented glucose-induced EndMT, whereas suppressing miR-9 caused glucose-like EndMT changes. We also found that preventing EndMT with miR-9 overexpression improved retinal vascular leakage in DR. Finally, we showed that miR-9 regulates EndMT at an early stage by regulating EndMT-inducing signals such as proinflammatory and TGF-β pathways.

Conclusions

We have shown that miR-9 is an important regulator of EndMT in DR, potentially making it a good target for RNA-based therapy in early DR.

Microperimetric analysis of diabetic macular edema after navigated direct photocoagulation with short-pulse laser for microaneurysms

BACKGROUND

Focal laser photocoagulation is an important treatment option for diabetic macular edema (DME). This study aimed to examine the retinal sensitivity (RS) and morphological changes at the coagulated site after direct photocoagulation of microaneurysms (MAs) in patients with DME using a navigated laser photocoagulator with a short-pulse duration of 30 ms.

METHODS

Images of early-phase fluorescein angiography were merged with images from the optical coherence tomography (OCT) map with 9 Early Treatment Diabetic Retinopathy Study grid circles, and MAs inside the edema area were selected for direct photocoagulation. The best-corrected visual acuity (BCVA), parameters of the OCT map including central retinal thickness and retinal thickness in edema range, central RS, and RS in the edema area were assessed at 1 and 3 months after the laser treatment. The RS points that overlapped with the laser spots were identified by merging the Navilas' digital treatment reports and the microperimetry images.

RESULTS

Seventeen eyes from 14 patients were studied. The mean retinal thickness in the edema range decreased at 3 months compared with pretreatment (P = 0.042), but the BCVA, central retinal thickness, central RS, and RS in the edema area remained unchanged. Overall, 32 of 400 sensitivity points overlapped with the laser-coagulated spots. The mean RS at these spots were 22.4 ± 5.3 dB at 1 month and 22.5 ± 4.8 dB at 3 months, with no significant change from the baseline of 22.7 ± 3.5 dB.

CONCLUSIONS

Retinal thickness improved in the coagulated edema area without a decrease in RS after direct photocoagulation of MAs with a short 30-ms pulse using Navilas. This promising therapeutic strategy for DME is effective and minimally invasive.

Prediction of OCT images of short-term response to anti-VEGF treatment for diabetic macular edema using different generative adversarial networks

PURPOSE

This study sought to assess the predictive performance of optical coherence tomography (OCT) images for the response of diabetic macular edema (DME) patients to anti-vascular endothelial growth factor (VEGF) therapy generated from baseline images using generative adversarial networks (GANs).

METHODS

Patient information, including clinical and imaging data, was obtained from inpatients at the Ophthalmology Department of Qilu Hospital. 715 and 103 pairs of pre-and post-treatment OCT images of DME patients were included in the training and validation sets, respectively. The post-treatment OCT images were used to assess the validity of the generated images. Six different GAN models (CycleGAN, PairGAN, Pix2pixHD, RegGAN, SPADE, UNIT) were applied to predict the efficacy of anti-VEGF treatment by generating OCT images. Independent screening and evaluation experiments were conducted to validate the quality and comparability of images generated by different GAN models.

RESULTS

OCT images generated f GAN models exhibited high comparability to the real images, especially for edema absorption. RegGAN exhibited the highest prediction accuracy over the CycleGAN, PairGAN, Pix2pixHD, SPADE, and UNIT models. Further analyses were conducted based on the RegGAN. Most post-therapeutic OCT images (95/103) were difficult to differentiate from the real OCT images by retinal specialists. A mean absolute error of 26.74 ± 21.28 μm was observed for central macular thickness (CMT) between the synthetic and real OCT images.

CONCLUSION

Different generative adversarial networks have different prognostic efficacy for DME, and RegGAN yielded the best performance in our study. Different GAN models yielded good accuracy in predicting the OCT-based response to anti-VEGF treatment at one month. Overall, the application of GAN models can assist clinicians in prognosis prediction of patients with DME to design better treatment strategies and follow-up schedules.

How to place the duality of specific MMP-9 inhibition for treatment of inflammatory bowel diseases into clinical opportunities?

Crohn’s disease (CD) and ulcerative colitis (UC) are inflammatory bowel diseases (IBD) with the involvement of immune cells and molecules, including cytokines, chemokines and proteases. A previous extensive review about the molecular biology of matrix metalloproteases (MMPs) and tissue inhibitors of metalloproteases (TIMPs), related to intestinal barrier destruction and restoration functions in IBD, is here complemented with the literature from the last five years. We also compare IBD as a prototypic mucosal inflammation of an epithelial barrier against microorganisms with inflammatory retinopathy as a disease with a barrier dysfunction at the level of blood vessels. Multiple reasons are at the basis of halting clinical trials with monoclonal antibodies against MMP-9 for IBD treatment. These include (i) the absence of a causative role of MMP-9 in the pathology in animal models of IBD, (ii) the fact that endotoxins, crossing the intestinal barrier, induce massive local release of both neutrophil collagenase (MMP-8) and gelatinase B (MMP-9), (iii) insufficient recognition that MMPs modify the activities of cytokines, chemokines and their receptors, (iv) ignorance that MMPs exist as mixtures of proteoforms with different posttranslational modifications and with different specific activities and (v) the fact that MMPs and TIMPs act in an interactive network, possibly having also beneficial effects on IBD evolution. Nevertheless, inhibition of MMPs may be a useful therapeutic approach during specific IBD disease phases or in specific sub-phenotypes. This temporary “window of opportunity” for MMP-9 inhibition may be complemented by a locoregional one, provided that the pharmacological agents are targeted in time to affected tissues, as is achieved in ophthalmological inflammation. Thus, in order to discover spatial and temporal windows of opportunity for MMP inhibition as treatment of IBD, more preclinical work including well controlled animal studies will be further needed. In this respect, MMP-9/NGAL complex analysis in various body compartments is helpful for better stratification of IBD patients who may benefit from anti-MMP-9.

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.