Diabetic macular edema: pathogenesis and treatment

Autonomous Screening for Diabetic Macular Edema Using Deep Learning Processing of Retinal Images

Objective

To develop and validate a deep learning model for diabetic macular edema (DME) detection using color fundus imaging, which is applicable in a diverse, multidevice clinical setting.

Design

Evaluation of diagnostic test or technology.

Subjects

A deep learning model was trained for DME detection using the EyePACS dataset, consisting of 32 049 images from 15 892 patients. The average age was 55.02%, and 51% of the patients were women.

Methods

Data were randomly assigned, by participant, into development (n = 14 246) and validation (n = 1583) sets. Analysis was conducted on the single image, eye, and patient levels. Model performance was evaluated using sensitivity, specificity, and the area under the receiver operating characteristic curve (AUC). Independent validation was further performed on the Indian Diabetic Retinopathy Image Dataset, as well as on new data.

Main Outcome Measures

Sensitivity, specificity, and AUC.

Results

At the image level, a sensitivity of 0.889 (95% confidence interval [CI]: 0.878, 0.900), a specificity of 0.889 (95% CI: 0.877, 0.900), and an AUC of 0.954 (95% CI: 0.949, 0.959) were achieved. At the eye level, a sensitivity of 0.905 (95% CI: 0.890, 0.920), a specificity of 0.902 (95% CI: 0.890, 0.913), and an AUC of 0.964 (95% CI: 0.958, 0.969) were achieved. At the patient level, a sensitivity of 0.900 (95% CI: 0.879, 0.917), a specificity of 0.900 (95% CI: 0.883, 0.911), and an AUC of 0.962 (95% CI: 0.955, 0.968) were achieved.

Conclusions

Diabetic macular edema can be detected from color fundus imaging with high performance on all analysis metrics. Automatic DME detection may simplify screening, leading to more encompassing screening for diabetic patients. Further prospective studies are necessary.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Choroidal thickness and vascularity in diabetic macular edema: impact of serous macular detachment

PURPOSE

This comparative study aimed to investigate the role of the choroidal vascular system in the formation of serous macular detachment (SMD) in diabetic macular edema (DME).

METHODS

A study population of 126 naive patients was divided into two groups: group 1 (DME without serous macular detachment, n = 90) and group 2 (DME with serous macular detachment, n = 36). The following assessments were conducted: best corrected visual acuity (BCVA), central macular thickness (CMT), the height of the SMD, subfoveal central choroidal thickness (SFCT), choroidal thickness at the nasal (SFNCT) and temporal (SFTCT) borders of the subfoveal 1500-micron area, choroidal thickness at the nasal (SMNCT) and temporal (SMTCT) borders of the submacular 6000-micron area, and subfoveal and submacular choroidal vascularity index (CVI).

RESULTS

BCVA was significantly better in group 1, whereas CMT was greater in group 2 (p = 0.002, p < 0.001, respectively). The logMAR BCVA was positively correlated with CMT in both groups (p < 0.001 for both, r = 0.940, and r = 0.920, respectively), but BCVA was not significantly correlated with SFCT, CVI or submacular CVI. Group 2 also showed significantly greater values for SFCT, SFNCT and SFTCT (p < 0.001) and SMNCT (p = 0.046); whereas SMTCT values showed no significant difference (p = 0.074). With regard to the subfoveal and submacular CVI, no significant differences were found between the groups (p = 0.142, p = 0.468).

CONCLUSION

While the presence of SMD in DME affects choroidal thickness, no significant difference was observed in the choroidal vascularity index. These findings may enlighten SMD pathogenesis, supporting the hypothesis that choroidal changes are not directly linked to alterations in vascular structure.

Ocular drug delivery systems based on nanotechnology: a comprehensive review for the treatment of eye diseases

Ocular drug delivery is a significant challenge due to the intricate anatomy of the eye and the various physiological barriers. Conventional therapeutic approaches, while effective to some extent, often fall short in effectively targeting ocular diseases, resulting in suboptimal therapeutic outcomes due to factors such as poor ocular bioavailability, frequent dosing requirements, systemic side effects, and limited penetration through ocular barriers. This review elucidates the eye's intricate anatomy and physiology, prevalent ocular diseases, traditional therapeutic modalities, and the inherent pharmacokinetic and pharmacodynamic limitations associated with these modalities. Subsequently, it delves into nanotechnology-based solutions, presenting breakthroughs in nanoformulations such as nanocrystals, liposomes, dendrimers, and nanoemulsions that have demonstrated enhanced drug stability, controlled release, and deeper ocular penetration. Additionally, it explores a range of nanosized carriers, including nano-structured lipid carriers, hydrogels, nanogels, nanoenzymes, microparticles, conjugates, exosomes, nanosuspensions, viral vectors, and polymeric nanoparticles, and their applications. Unique insights include emerging innovations such as nanowafers and transcorneal iontophoresis, which indicate paradigm shifts in non-invasive ocular drug delivery. Furthermore, it sheds light on the advantages and limitations of these nanotechnology-based platforms in addressing the challenges of ocular drug delivery. Though nano-based drug delivery systems are drawing increasing attention due to their potential to enhance bioavailability and therapeutic efficacy, the review ends up emphasizing the imperative need for further research to drive innovation and improve patient outcomes in ophthalmology.

Efficacy of ranibizumab and aflibercept on reducing maximum diameter of largest cyst in diabetic cystoid macular edema: MARMASIA study group

PurposeThis study aimed to compare the effect of intravitreal aflibercept (IVA) and ranibizumab (IVR) on the maximal diameter of the largest intraretinal cyst (mdIRC), indicating chronicity in patients with diabetic cystoid macular edema (CME).MethodsThis retrospective, comparative study included a subgroup of patients from the MARMASIA Study with treatment-naïve diabetic CME who had IVA (IVA group) or IVR (IVR group) on a pro re nata regimen after a loading dose of 3-monthly injections and followed-up for 24 months. Best-corrected visual acuity (logMAR), central macular thickness (CMT, µm), and mdIRC (µm) and their changes during the study period in the IVA and IVR groups were compared.ResultsA total of 175 eyes (65 [37.1%] in IVA and 110 [62.9%] in IVR group) of 113 patients were included in the study analysis. Both groups had statistically significant improvements in BCVA and CMT during the follow-up (p < 0.05 for all), which were comparable between the groups at each time point. However, the mean reduction in mdIRCs was consistently and significantly higher in the IVA group compared to the IVR group at each follow-up examination (F[1, 3.52] = 6.93, p = 0.009).ConclusionIVA seems to have a greater impact in reducing cyst sizes than IVR in diabetic CME.

Detection of diabetic macular oedema patterns with fine-grained image categorisation on optical coherence tomography

PURPOSE

To develop an artificial intelligence (AI) system for detecting pathological patterns of diabetic macular oedema (DME) with fine-grained image categorisation using optical coherence tomography (OCT) images.

METHODS

The development of the AI system consists of two parts, a pretraining process on a public dataset (Asia Pacific Tele-Ophthalmology Society (APTOS)), and the training process on the local dataset. The local dataset was partitioned into the training set, validation set and test set in the ratio of 6:2:2. The Split Subspace Attention Network (SSA-Net) architecture was adopted to train independent models to detect the seven pathological patterns of DME: intraretinal fluid (IRF), subretinal fluid (SRF), pigment epithelial detachment (PED), hyper-reflective retinal foci (HRF), Müller cell cone disruption (MCCD), subretinal hyper-reflective material (SHRM) and intra-cystic hyper-reflective material (ICHRM). The confusion matrix, sensitivity, specificity and receiver operating characteristic (ROC) were used to evaluate the performance of the models.

RESULTS

The APTOS public dataset consists of 33 853 OCT images and the local dataset consists of 1346 OCT images with DME. In the pretraining process on the public dataset, the accuracy was 0.652 for IRF, 0.928 for SRF, 0.936 for PED and 0.975 for HRF. After the training process on the local dataset, the SSA-Net architecture showed better performance in fine-grained image categorisation on the test set. The area under the ROC curve was 0.980 for IRF, 0.995 for SRF, 0.999 for PED, 0.908 for MCCD, 0.887 for HRF, 0.990 for SHRM and 0.972 for ICHRM. The AI system outputs a heatmap for each result, which can give a visual explanation for the automated identification process. The heatmaps revealed that the regions of interest of the AI system were consistent with the retinal experts.

CONCLUSIONS

The proposed SSA-Net architecture for detecting the pathological patterns of DME achieved satisfactory accuracy. However, this study was conducted in one medical centre, and multicentre trials will be needed in the future.

Long-term visual outcomes and fluid compartment changes in limited-early versus early response to anti-VEGF treatment for diabetic macular edema

OBJECTIVE

This study assessed best visual acuity (BVA) and central subfield thickness (CST) outcomes for LER (limited early responder) and ER (early responder) patients at 24 and 36 months.

DESIGN

Retrospective chart review PARTICIPANTS: One-hundred and twelve patients characterized at 3 months after their first anti-VEGF injections as either LER if they met the anatomic criteria (aLER = CST reductions ≤ 10%), visual criteria (vLER = ETDRS letter gains < 5 letter), or both (cLER). All other patients were classified as ER (aER/vER/cER).

METHODS

Variables collected include CST and ETDRS letters at baseline, 3, 24, and 36 months following injections, comorbidities, smoking status, demographics, baseline systemic factors, and the type and quantity of anti-VEGF injections. Analyses were performed using Welch's t-test, multivariable linear and multivariable logistic regression.

RESULTS

BVA changes from 3 months were significant between cLER versus cER and vLER versus vER groups (p < 0.05). There was a greater decrease in mean BVA from 3 months to 36 months in the cER group compared to the cLER group. Alternatively, mean BVA decreased in the vER cohort, while the vLER cohort slightly increased. CST changes from 3 months were statistically significant (p < 0.01) between all LER and ER groups with LER groups showing greater reductions compared to ER counterparts. BVA and CST changes from baseline to 24 and 36 months were not significant after controlling for baseline differences between LER and ER groups.

CONCLUSION

Results highlight the value of long-term anti-VEGF treatment and the need to further explore options that may lead to continued BVA improvements beyond 3 months.

Current Treatment Options for Diabetic Retinal Disease

The global incidence of diabetes is rising steadily and with it the number of people living with diabetic retinal disease (DRD) is increasing. Like diabetes, DRD can be treated but not cured. In response, therapies to address DRD include targeted ocular and systemic medications. This review discusses diabetes and DRD in terms of current screening recommendations, treatments, and considerations related to those therapies and future drug targets and trials on the horizon. This discourse is targeted at all members of the diabetes care team, including primary care providers, optometrists, and ophthalmologists. The dynamic landscape of diabetic retinopathy treatment is promising for the prevention and improvement of visually significant disease.

Efficacy of Intravitreal Dexamethasone Implant (Ozurdex®) in Naïve and Refractory Patients with Different Morphological Subtypes of Diabetic Macular Edema

Background and Objectives: To investigate anatomical and functional outcomes in different morphological subtypes of diabetic macular edema (DME) treated with an intravitreal dexamethasone implant (Ozurdex) over 6 months follow-up. Materials and Methods: A retrospective, comparative study on patients with DME who received an intravitreal dexamethasone implant. Best-corrected visual acuity (BCVA), central subfoveal thickness (CST) and maximum CST on optical coherence tomography (OCT) were measured. The recruits were divided into three groups based on the morphological patterns of DME: serous retinal detachment (SRD), cystic macular edema (CME) and diffuse retinal thickening (DRT). The presence or absence of previous treatment were considered as being previously treated with anti-VEGF (PT) vs. naïve eyes (TN). All subjects received a single injection of the dexamethasone implant. The primary outcomes included changes in BCVA, CST and CSTMax at 2-, 4- and 6-months of follow-up. Results: CST was significantly reduced following one dexamethasone injection in the whole cohort from a total mean value of 513.3 μm to 368.2 μm at 2 months, 447.2 μm at 4 months and 471.5 μm at 6 months. The change in CST was significantly greater in SRD as opposed to the DRT and CME group at all time points. Overall, BCVA improved from 0.82 at baseline to 0.75 and 0.76 LogMAR at 2 and 4 months, respectively, whilst showing an overall deterioration to 0.84 at 6 months. The CME group showed the best BCVA at 6 months. Concerning treatment status (TN vs. PT), there was no significant difference in CST at 2 and 4 months, while CST was reduced at 6 months for the PT group (p = 0.023). Similarly, BCVA was significantly better in the PT group at 6 months (p = 0.017). Conclusions: The dexamethasone implant was effective in reducing DME and providing short-term BCVA improvement. The presence of SRD was associated with more favorable anatomical results, while CME was associated with better visual acuity. Dexamethasone provided superior results in previously treated patients.

Assessment the real-world safety of intravitreal dexamethasone implant (Ozurdex): novel insights from a comprehensive pharmacovigilance analysis utilizing the FAERS database

OBJECTIVE

The intravitreal dexamethasone implant (Dex) is widely used for various ocular conditions, including diabetic macular edema (DME), retinal vein occlusion (RVO), and non-infectious uveitis. Despite its efficacy, concerns remain regarding its safety profile. This study aims to analyze the adverse events (AEs) associated with Dex reported in the FDA Adverse Event Reporting System (FAERS) database from 2010 to 2024.

METHODS

Data were extracted from FAERS, focusing on cases where Dex was the primary suspect drug. The dataset was processed to eliminate duplicates and incomplete entries. Disproportionality analysis, including Reporting Odds Ratio (ROR) and Proportional Reporting Ratio (PRR), was used to detect safety signals. AEs were categorized by system organ class (SOC) and preferred term (PT).

RESULTS

A total of 1,588 adverse event reports (AERs) were analyzed, revealing a significant upward trend. The Eye disorders was the most commonly reported SOC, with strong disproportionality signals (ROR: 45.11; PRR: 23.71). Key AEs identified at the PT level included Corneal decompensation, Choroidal hematoma, and Posterior capsule rupture, which were not listed on the drug label. Considering the reported numbers, the Endophthalmitis was the most common AE. Additionally, a significant proportion of AEs were observed within the first seven days post-administration, emphasizing the need for monitoring.

CONCLUSION

While Dex remains an effective treatment option for ocular conditions, its use is associated with significant risks, particularly regarding unexpected and severe complications such as corneal decompensation. Continuous pharmacovigilance and detailed patient monitoring are essential to mitigate these risks. Future studies should focus on prospective designs and comprehensive clinical data to better understand the safety profile of Dex.

Automated and code-free development of a risk calculator using ChatGPT-4 for predicting diabetic retinopathy and macular edema without retinal imaging

BACKGROUND

Diabetic retinopathy (DR) and macular edema (DME) are critical causes of vision loss in patients with diabetes. In many communities, access to ophthalmologists and retinal imaging equipment is limited, making screening for diabetic retinal complications difficult in primary health care centers. We investigated whether ChatGPT-4, an advanced large-language-model chatbot, can develop risk calculators for DR and DME using health check-up tabular data without the need for retinal imaging or coding experience.

METHODS

Data-driven prediction models were developed using medical history and laboratory blood test data from diabetic patients in the Korea National Health and Nutrition Examination Surveys (KNHANES). The dataset was divided into training (KNHANES 2017-2020) and validation (KNHANES 2021) datasets. ChatGPT-4 was used to build prediction formulas for DR and DME and developed a web-based risk calculator tool. Logistic regression analysis was performed by ChatGPT-4 to predict DR and DME, followed by the automatic generation of Hypertext Markup Language (HTML) code for the web-based tool. The performance of the models was evaluated using areas under the curves of receiver operating characteristic curve (ROC-AUCs).

RESULTS

ChatGPT-4 successfully developed a risk calculator for DR and DME, operational on a web browser without any coding experience. The validation set showed ROC-AUCs of 0.786 and 0.835 for predicting DR and DME, respectively. The performance of the ChatGPT-4 developed models was comparable to those created using various machine-learning tools.

CONCLUSION

By utilizing ChatGPT-4 with code-free prompts, we overcame the technical barriers associated with using coding skills for developing prediction models, making it feasible to build a risk calculator for DR and DME prediction. Our approach offers an easily accessible tool for the risk prediction of DM and DME in diabetic patients during health check-ups, without the need for retinal imaging. Based on this automatically developed risk calculator using ChatGPT-4, health care workers will be able to effectively screen patients who require retinal examinations using only medical history and laboratory data. Future research should focus on validating this approach in diverse populations and exploring the integration of more comprehensive clinical data to enhance predictive performance.

ADAMTS13 Improves Endothelial Function and Reduces Inflammation in Diabetic Retinopathy

The protease, a disintegrin and metalloproteinase with thrombospondin type 1 motif member 13 (ADAMTS13), known to cleave only the von Willebrand factor (VWF), has powerful regulatory effects on microvascular platelet adhesion, thrombosis, inflammation, and endothelial dysfunction. We study the protection against diabetes-induced retinal injury in experimental rats by supplementation with recombinant ADAMTS13. We compare human epiretinal membranes and vitreous samples from nondiabetic subjects and patients with proliferative diabetic retinopathy (PDR) and extend in vitro analyses with the use of various immunodetection and spectrofluorimetric methods on rat retina and human retinal glial and endothelial cell cultures. Functional studies include the assessment of the blood-retinal barrier (BRB), cell adhesion, and in vitro angiogenesis. In epiretinal membranes, endothelial cells and monocytes/macrophages express ADAMTS13. The levels of VWF, the platelet marker CD41, ADAMTS13, and the biomarkers of endothelial cell injury soluble VE-cadherin and soluble syndecan-1 are increased in PDR vitreous. ADAMTS13 is downregulated in diabetic rat retinas. The intravitreal administration of ADAMTS13 attenuates diabetes-induced BRB breakdown, the downregulation of VE-cadherin and β-catenin, and the upregulation of VWF, CD41, phospho-ERK1/2, HMGB1, VCAM-1, and ICAM-1. In Müller cells, ADAMTS13 attenuates MCP-1, MMP-9, and ROS upregulation induced by diabetic mimetic conditions. In HRMECs, ADAMTS13 attenuates the shedding of the soluble VE-cadherin and soluble syndecan-1 and the levels of phospho-ERK1/2, MCP-1, fractalkine, and ROS induced by diabetic mimetic conditions, the upregulation of ICAM-1 and VCAM-1 elicited by TNF-α, the adherence of monocytes induced by TNF-α, and VEGF-induced migration of human retinal microvascular endothelial cells. Our findings suggest that enhancing ADAMTS13 levels in situ ameliorates diabetes-induced retinal inflammation and vascular dysfunction.

Targeting pericyte retention in Diabetic Retinopathy: a review

Diabetic retinopathy is a common yet severe complication of diabetes mellitus and is the leading cause of blindness in middle-aged adults. After years of poorly managed hyperglycemia, complications begin as non-proliferative diabetic retinopathy but can then progress into the proliferative stage marked by neovascularization of the retina. Multiple pathologic mechanisms caused by chronic hyperglycemia damage the retinal vasculature leading to pericyte drop out and the progression of the disease. This review outlines the major pathways of pathogenesis in diabetic retinopathy, highlighting the protective role pericytes play in preserving the blood-retinal barrier. Given the loss of this cell line is a defining feature of the disease, ways in which to prevent pericyte dropout within retinal vasculature is discussed, targeting various pathogenesis pathways of diabetic retinopathy.

Intraoperative OCT-Guided Selective Epiretinal Membrane (ERM) Peeling Versus ERM and Internal Limiting Membrane Peeling for Tractional Macular Edema in Diabetic Eyes

BACKGROUND AND AIM

Despite the abundant literature, internal limiting membrane (ILM) peeling remains a controversial topic, especially in diabetic eyes. We compared the safety and effectiveness of intraoperative optical coherence tomography (iOCT)-assisted selective epiretinal membrane (ERM) peeling with dye-assisted ERM and ILM peeling, for the treatment of tractional diabetic macular edema (tDME).

MATERIAL AND METHODS

In this single-center retrospective study, we evaluated consecutive patients with tDME who underwent iOCT-assisted selective ERM peeling (Group A) or "dual blue" dye-assisted ERM and ILM peeling (Group B). Best corrected visual acuity (BCVA) and central macular thickness (CMT) were compared over a 12-month follow-up. A linear mixed model analysis was performed.

RESULTS

At baseline, the two groups were comparable in terms of their demographic and clinical outcomes. No significant difference between BCVA and CMT was observed among the groups. Both groups showed significant improvement in outcomes at the last follow-up (p < 0.001), although only iOCT-assisted ERM peeling ensured significant visual gain and macular thinning (p < 0.001) one month after surgery. A significant effect of time on both outcomes (p < 0.001) and of time-treatment interaction on visual change (p = 0.02) were observed. In eight patients, macular edema recurred (Group A: two patients; Group B: six patients) and was managed with an intravitreal dexamethasone implant. In Group A, one patient developed a recurrence of ERM without the need for reoperation.

CONCLUSIONS

iOCT-assisted ERM removal may be as effective as dye-assisted ERM and ILM peeling to treat tDME. Additionally, it ensures a quicker recovery of visual function and macular thickness. The observed ERM recurrence within the 1-year follow-up was mild and did not necessitate additional surgery.

Clinical and optical coherence tomography biomarkers as prognostic factors in dexamethasone intravitreal implant for diabetic macular edema

PURPOSE

Aim of the study was to evaluate the efficacy of dexamethasone (DEX) 0.7 mg intravitreal implant in patients with diabetic macular edema (DME) and serous retinal detachment (SRD), and to study the prognostic factors on a follow up of 12 months.

METHODS

Forty eyes of twenty- six patients with centre involving DME and SRD, who underwent DEX implant, were enrolled. Best-corrected visual acuity (BCVA), Swept source OCT imaging and intraocular pressure were evaluated. Central macular thickness (CMT), vitreomacular adhesion (VMA), disorganization of retinal inner layers (DRILs), hyperreflective dots (HRD), SRD and ellipsoid zone (EZ) disruption were included in the analysis at baseline and 12 months after implant.

RESULTS

According to our parametric analysis, at 12 months, BVCA improvement from 48.6 ± 23.4 letters to 53.3 ± 24.5 letters was statistically significant (p = 0.04), CMT decreased from 460 ± 99.52 μm to 322.9 ± 117 μm. The presence at baseline of VMA (p = 0.01), EZ disruption (p = 0.03) and DRILs (p = 0.04), were associated with poor BCVA improvement at the end of follow-up.

CONCLUSION

In conclusion, OCT biomarkers can be considered significant prognostic factors for treatment outcome in patients with DME undergoing DEX intravitreal implant.

Management of treatment-naïve diabetic macular edema patients: Review of real-world clinical data

The high prevalence of Diabetic macular edema (DME) is a real global health problem. Its complex pathophysiology involves different pathways. Over the last decade, the introduction of intravitreal treatments has dramatically changed the management and prognosis of DME. Among the different treatment options, inhibitors of vascular endothelial growth factor (anti-VEGF) and intravitreal steroids implants represent the first-line therapy of DME. We conducted a review of electronic databases to compile the available evidence about the clinical management of DME in a clinical setting, with a special focus on treatment-naïve patients. Anti-VEGF therapies represent a valuable option for treating DME patients. However, many patients do not respond properly to this treatment and, due to its administration regimen, many patients receive suboptimal treatment in real life. Current evidence demonstrated that in patients with DME, DEX-i improved significantly both anatomic and visual outcomes. Besides eyes with insufficient anti-VEGF respond or recalcitrant DME cases, DEX-i can be effectively and safely used in treatment-naïve DME patients as first line therapy. DEX-i may be considered first line therapy in different clinical scenarios, such as DME eyes with a greater inflammatory component, patients with cardiovascular events, vitrectomized eyes, or those requiring cataract surgery. In conclusion, there are still many points for improvement pending in the clinical management of the patient with DME. Since DME treatment must follow a patient-tailored approach, selecting the best therapeutic approach for each patient requires a good understanding of the pathophysiology of DME.

Prevalence of Diabetic Macular Edema Using Optical Coherence Tomography in Type 2 Diabetics With Nephropathy in Comparison With Type 2 Diabetics Without Nephropathy

INTRODUCTION

 The primary vision-threatening complication in patients with diabetic retinopathy (DR) is diabetic macular edema (DME). Diabetic nephropathy (DN) often has DR that threatens their vision and has a risk of developing DME. Hence, the presence of DN could be the only risk factor for developing DME without the presence of other factors. Hence, this study proposes to predict the prevalence of DME using optical coherence tomography (OCT) in type 2 diabetics with nephropathy in comparison with diabetics without nephropathy.

METHODS

This is a cross-sectional study done on patients visiting the Ophthalmology Department at Saveetha Medical College and Hospital, Chennai, for one year. A total of 120 patients were included in the study, with 60 diabetic patients without nephropathy in Group 1 and 60 diabetic patients with nephropathy in Group 2. A detailed history was recorded. Their recent blood reports of fasting blood sugar, postprandial blood sugar, hemoglobin A1c (HbA1c), renal function test, and urine protein/creatinine ratio were all noted. Chronic kidney disease (CKD) staging in nephropathy patients as done by the nephrologist was also documented. The best corrected visual acuity (BCVA) was assessed for distant and near vision. A slit lamp examination and dilated fundus examination were done. Fundus findings were independently graded according to the Early Treatment Diabetic Retinopathy Study (ETDRS) classification. OCT was done in all patients to confirm DME.

RESULTS

In our study. males and females were 60 each in number. The majority of patients (32.5%) were >70 years old. A small percentage of patients (1.7%) in Group 1 had DM of >10 years, and 41.7% of the patients in Group 2 had DM of >10 years. Meanwhile, 73.3% of the patients in Group 1 had an HbA1c level between 6% and 7.5%, and 83.3% of the patients in Group 2 had an HbA1c level >7.5%. The percentage of patients with DME in Group 1 was 1.7%, and that in Group 2 was 21.7%. The majority of patients who had BCVA of 6/6 were in Group 1. The majority of patients with DME (46.4%) had stage V nephropathy.

CONCLUSION

The coexistence of nephropathy in diabetic patients increases the incidence of DME. With long-standing diabetes and uncontrolled blood sugar levels being risk factors for developing DN and subsequently DME, such patients are to be screened regularly and advised on adequate glycemic control for achieving good visual prognosis and limit retinopathy progression. Moreover, the severity of DN should be kept in mind by nephrologists, and patients are to be promptly referred to the ophthalmology department for complete evaluation.

Correlation of limited-early-response status with 12-month CST, BVA, and machine learning-quantified retinal fluid in diabetic macular oedema in routine clinical practice

BACKGROUND/OBJECTIVES

Anti-VEGF treatment response in DMO has been measured by changes in the central subfield thickness (CST) and best visual acuity (BVA) outcomes at 3 months after initial treatment, termed early or limited early response (ER/LER). This study correlates LER with 12-month BVA, CST, and retinal fluid volumes quantified by a machine learning algorithm on optical coherence tomography (OCT).

SUBJECTS/METHODS

The study included treatment naïve DMO patients ≥ 18 years with OCT scans at baseline (M0), M3, M6, and M12. The 220 patients were categorized as limited early responders (LER) if they had ≤ 10% CST reduction and/or < 5 ETDRS letter gain at M3. BVA, CST, and subretinal (SRF), intraretinal (IRF), and total retinal (TRF) fluid volumes quantified by a machine learning algorithm were compared between groups and across time.

RESULTS

At M12, the anatomic LER (aLER), defined solely by CST, had significantly worse BVA and CST versus the anatomic ER (aER) group (p < 0.001). Retinal fluid M12 outcomes did not significantly vary between all LER and ER groups. No significant BVA, CST, TRF, and IRF variance across time for LER was found (p > 0.1).

CONCLUSIONS

BVA and CST M12 outcomes vary by aLER/aER status indicating that CST may be a strong predictor of treatment outcomes, while retinal fluid volumes were not predicted by LER status.

Effect of anti-vascular endothelial growth factor on early-stage post-vitrectomy macular edema in patients with proliferative diabetic retinopathy

PURPOSE

To investigate the effectiveness of anti-vascular endothelial growth factor (VEGF) therapy on post-vitrectomy macular edema (PVME) and determine the risk factors for PVME recovery.

METHODS

This retrospective study included 179 eyes of 179 patients who underwent pars plana vitrectomy for proliferative diabetic retinopathy and developed PVME within 3 months after surgery. Eyes were grouped according to postoperative anti-VEGF treatment.

RESULTS

Central retinal thickness (CRT) decreased significantly from baseline to 3-month follow-up in groups with (509.9 ± 157.2 μm vs. 401.2 ± 172.1 μm, P < 0.001) or without (406.1 ± 96.1 μm vs. 355.1 ± 126.0 μm, P = 0.008) postoperative anti-VEGF treatment. Best-corrected visual acuity (BCVA) did not differ between the two groups during follow-up. In the group not receiving anti-VEGF therapy, BCVA was significantly improved at 1, 2, and 3 months (P = 0.007, P < 0.001, and P < 0.001, respectively), while in the anti-VEGF group, BCVA was significantly improved at 1 and 3 months (P = 0.03 and P < 0.001). A thicker baseline CRT (β = 0.44; 95% confidence interval, 0.26-0.61; P < 0.001) was significantly associated with decreasing CRT.

CONCLUSION

PVME tends to spontaneously resolve in the early postoperative period. The effect of anti-VEGF therapy in the first 3 months after diagnosis appears to be limited.

Macular vascular and photoreceptor changes for diabetic macular edema at early stage

This study was intended to investigate the macular vascular and photoreceptor changes for diabetic macular edema (DME) at the early stage. A total of 255 eyes of 134 diabetes mellitus patients were enrolled and underwent an ophthalmological and systemic evaluation in this cross-sectional study. Early DME was characterized by central subfoveal thickness (CST) value between 250 and 325 μm, intact ellipsoid zone, and an external limiting membrane. While non-DME was characterized by CST < 250 μm with normal retinal morphology and structure. Foveal avascular zone (FAZ) area ≤ 0.3 mm2 (P < 0.001, OR = 0.41, 95% CI 0.26-0.67 in the multivariate analysis) and HbA1c level ≤ 8% (P = 0.005, OR = 0.37, 95% CI 0.19-0.74 in multivariate analysis) were significantly associated with a higher risk of early DME. Meanwhile, no significant differences exist in cone parameters between non-DME and early DME eyes. Compared with non-DME eyes, vessel diameter, vessel wall thickness, wall-to-lumen ratio, the cross-sectional area of the vascular wall in the upper side were significantly decreased in the early DME eyes (P = 0.001, P < 0.001, P = 0.005, P = 0.003 respectively). This study suggested a vasospasm or vasoconstriction with limited further photoreceptor impairment at the early stage of DME formation. CST ≥ 250 μm and FAZ ≤ 0.3 mm2 may be the indicator for early DME detection.

Perfusion Deficits in Diabetes Without Retinopathy Localize to the Perivenular Deep Capillaries Near the Fovea on OCT Angiography

Purpose

To localize early capillary perfusion deficits in patients with diabetes mellitus (DM) without clinical diabetic retinopathy (DR) using averaged OCT angiography (OCTA).

Design

Retrospective cross-sectional study.

Participants

Patients with DM without DR and healthy controls.

Methods

We measured perfusion deficits in the full retina, superficial capillary plexus (SCP), and deep capillary plexus (DCP) on averaged 3 × 3-mm OCTA images. Perfusion deficits were defined as the percentage of retinal tissue located >30 μm from blood vessels, excluding the foveal avascular zone (FAZ). One eye from each patient was selected based on image quality. We measured deficits in the parafoveal region, the 300 μm surrounding the FAZ, and 300 to 1000 μm surrounding the FAZ. If a capillary layer within one of these regions was significantly different in DM without DR compared with controls, we further characterized the location of perfusion deficit as periarteriolar, perivenular, or the capillaries between these 2 zones.

Main Outcome Measures

Location of increased perfusion deficits in patients with DM without DR compared with controls.

Results

Sixteen eyes from 16 healthy controls were compared with 16 eyes from 16 patients with DM without DR (age 45.1 ± 10.7 and 47.4 ± 15.2 years respectively, P = 0.64). Foveal avascular zone area and perfusion deficits in the entire parafovea and the 300 to 1000-μm ring around the FAZ were not significantly different between groups (P > 0.05 for all). Perfusion deficits in 300 μm around the FAZ were significantly increased in patients with DM without DR in full retinal thickness, SCP, and DCP (P < 0.05 for all). When analyzing the perivenular, periarteriolar, and capillary zones, only the perivenular DCP perfusion deficits were significantly increased (5.03 ± 2.92% in DM without DR and 2.73 ± 1.97% in controls, P = 0.014).

Conclusions

Macular perfusion deficits in patients with DM without DR were significantly increased in the region nearest the FAZ, mainly at the perivenular deep capillaries. Further research on these early changes may improve our understanding of the capillaries most susceptible to vascular injury and disruption during diabetes.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Ensemble learning for retinal disease recognition under limited resources

Retinal optical coherence tomography (OCT) images provide crucial insights into the health of the posterior ocular segment. Therefore, the advancement of automated image analysis methods is imperative to equip clinicians and researchers with quantitative data, thereby facilitating informed decision-making. The application of deep learning (DL)-based approaches has gained extensive traction for executing these analysis tasks, demonstrating remarkable performance compared to labor-intensive manual analyses. However, the acquisition of retinal OCT images often presents challenges stemming from privacy concerns and the resource-intensive labeling procedures, which contradicts the prevailing notion that DL models necessitate substantial data volumes for achieving superior performance. Moreover, limitations in available computational resources constrain the progress of high-performance medical artificial intelligence, particularly in less developed regions and countries. This paper introduces a novel ensemble learning mechanism designed for recognizing retinal diseases under limited resources (e.g., data, computation). The mechanism leverages insights from multiple pre-trained models, facilitating the transfer and adaptation of their knowledge to retinal OCT images. This approach establishes a robust model even when confronted with limited labeled data, eliminating the need for an extensive array of parameters, as required in learning from scratch. Comprehensive experimentation on real-world datasets demonstrates that the ensemble models constructed by the proposed ensemble method show superior performance over the baseline models under sparse labeled data, especially the triple ensemble model, which achieves the accuracy of 92.06%, which is 8.27%, 7.99%, and 11.14% better than the three baseline models, respectively. In addition, compared with the three baseline models learned from scratch, the triple ensemble model has fewer trainable parameters, only 3.677M, which is lower than the three baseline models of 8.013M, 4.302M, and 20.158M, respectively.

Allopurinol and the Risk of Diabetic Macular Edema among U.S. Veterans with Type 2 Diabetes

BACKGROUND

By inhibiting xanthine oxidase, subsequent inflammatory cytokine release and the resulting breakdown of the blood-retina barrier, allopurinol may limit the inflammation-driving diabetic macular edema (DME).

METHODS

We examined the relationship between allopurinol and DME among type 2 diabetic United States veterans using a retrospective cohort study.  We used propensity score matching and Cox hazard models to estimate the risk of DME.

RESULTS

Propensity score-matched Cox models revealed allopurinol was associated with a 24.6% reduction in the risk of DME (HR = 0.754; 95% CI = (0.684-0.831)).

CONCLUSION

Allopurinol could reduce the risk of DME, one of the major causes of visual disturbance among diabetic patients. Further research into the effects of allopurinol on DME is warranted.

Comparing the efficacy of dexamethasone implant and anti-VEGF for the treatment of macular edema: A systematic review and meta-analysis

OBJECTIVES

To evaluate the clinical efficacy of dexamethasone (DEX) implant, for the treatment of macular edema (ME) caused by retinal vein occlusion (RVO) and diabetic retinopathy (DR) through a systematic review and meta-analysis.

METHODS

The PubMed, Embase and Cochrane Library databases were comprehensively searched from inception to November 21, 2022, for studies evaluating the clinical efficacy of DEX implant for patients with retinal vein occlusion macular edema (RVO-ME) or diabetic macular edema (DME). Randomized controlled trials (RCTs) published in English were considered eligible. The Cochrane Collaboration tool was applied to assess the risk of bias in each study. Effect estimates with 95% confidence intervals (CIs) were pooled using the random effects model. We also conducted subgroup analyses to explore the sources of heterogeneity and the stability of the results.

RESULTS

This meta-analysis included 8 RCTs (RVO-ME [n = 2] and DME [n = 6]) assessing a total of 336 eyes. Compared with anti-VEGF therapy, DEX implant treatment achieved superior outcomes in terms of best corrected visual acuity (BCVA) (mean difference [MD] = -3.68 ([95% CI, -6.11 to -1.25], P = 0.003), and no heterogeneity was observed (P = 0.43, I2 = 0%). DEX implant treatment also significantly reduced central macular thickness (CMT) compared with anti-VEGF treatment (MD = -31.32 [95% CI, -57.92 to -4.72], P = 0.02), and there was a high level of heterogeneity between trials (P = 0.04, I2 = 54%). In terms of severe adverse events, DEX implant treatment had a higher risk of elevated intraocular pressure than anti-VEGF therapy (RR = 6.98; 95% CI: 2.16 to 22.50; P = 0.001), and there was no significant difference in cataract progression between the two groups (RR = 1.83; 95% CI: 0.63 to 5.27, P = 0.31).

CONCLUSIONS

Compared with anti-VEGF therapy, DEX implant treatment is more effective in improving BCVA and reducing ME. Additionally, DEX implant treatment has a higher risk of elevated intraocular pressure. Due to the small number of studies and the short follow-up period, the results should be interpreted with caution. The long-term effects of the two treatments need to be further determined.

TRIAL REGISTRATION

Prospero Registration Number CRD42021243185.

Optical coherence tomography angiography for detection of microvascular changes in early diabetes: A systematic review and meta-analysis

AIMS

To evaluate the effectiveness of optical coherence tomography angiography (OCTA) in detecting early intraocular microvascular changes in diabetic patients.

MATERIALS AND METHODS

A systematic study search was performed on PubMed, Medline, Embase, and the Cochrane Library, ranging from January 2012 to March 2023. Controlled studies compared diabetes mellitus (DM) patients with non-diabetic retinopathy (NDR) or patients with mild non-proliferative diabetic retinopathy (mild NPDR) to healthy people. These studies included parameters of OCTA such as foveal avascular zone (FAZ), vessel density of superficial capillary plexus (VDscp), vessel density of deep capillary plexus (VDdcp), and peripapillary VD. The relevant effect model was used according to the heterogeneity, and the mean difference and 95% confidence intervals were calculated.

RESULTS

A total of 18 studies with 2101 eyes were eventually included in this meta-analysis. Our results demonstrated that early alterations of VDscp, VDdcp, and peripapillary VD in NDR patients had a significant difference compared with healthy people by OCTA (VDscp: WMD = -1.34, 95% CI: -1.99 to -0.68, P < 0.0001. VDdcp: WMD = -2.00, 95% CI: -2.95 to -1.04, P < 0.0001. Peripapillary VD: WMD = -1.07, 95% CI: -1.70 to -0.43, P = 0.0010). However, there was no statistically significant difference in total FAZ between them (WMD = -0.00, 95% CI: -0.02-0.01, P = 0.84). In addition, for patients with mild NPDR, OCTA could illustrate prominent changes in VDscp, VDdcp, and total FAZ compared with healthy people (VDscp: WMD = -6.11, 95% CI: -9.90 to -2.32, P = 0.002. VDdcp: WMD = -4.26, 95% CI: -5.95 to -2.57, P < 0.00001. FAZ: WMD = 0.06, 95% CI: 0.01-0.11, P = 0.03).

CONCLUSIONS

In diabetic patients with or without retinopathy, the parameters of OCTA such as VDscp, VDdcp, and peripapillary vessel density were demonstrated as potential biomarkers in monitoring the early alterations of retinal microangiopathy, while total FAZ may have no significant changes in diabetic patients without retinopathy.

FNeXter: A Multi-Scale Feature Fusion Network Based on ConvNeXt and Transformer for Retinal OCT Fluid Segmentation

The accurate segmentation and quantification of retinal fluid in Optical Coherence Tomography (OCT) images are crucial for the diagnosis and treatment of ophthalmic diseases such as age-related macular degeneration. However, the accurate segmentation of retinal fluid is challenging due to significant variations in the size, position, and shape of fluid, as well as their complex, curved boundaries. To address these challenges, we propose a novel multi-scale feature fusion attention network (FNeXter), based on ConvNeXt and Transformer, for OCT fluid segmentation. In FNeXter, we introduce a novel global multi-scale hybrid encoder module that integrates ConvNeXt, Transformer, and region-aware spatial attention. This module can capture long-range dependencies and non-local similarities while also focusing on local features. Moreover, this module possesses the spatial region-aware capabilities, enabling it to adaptively focus on the lesions regions. Additionally, we propose a novel self-adaptive multi-scale feature fusion attention module to enhance the skip connections between the encoder and the decoder. The inclusion of this module elevates the model's capacity to learn global features and multi-scale contextual information effectively. Finally, we conduct comprehensive experiments to evaluate the performance of the proposed FNeXter. Experimental results demonstrate that our proposed approach outperforms other state-of-the-art methods in the task of fluid segmentation.

The effect of glycosylated hemoglobin levels on the response to intravitreal dexamethasone implant for treating diabetic macular edema

This study investigates the impact of glycosylated hemoglobin (HbA1c) on the efficacy of intravitreal dexamethasone (DEX) implants in patients with diabetic macular edema (DME) over a 12-month period. We retrospectively reviewed 90 DME patients treated with DEX implants, categorizing them based on baseline HbA1c levels (≤ 7% and > 7%) and 12-month changes in HbA1c ("improved", "stable", "worsened"). At the 2-month mark, the mean central subfield thickness (CST) reduction in the HbA1c ≤ 7% group was - 147.22 ± 113.79 µm compared to -130.41 ± 124.50 µm in the > 7% group (p = 0.506). Notably, 12-month outcomes between these groups showed no significant difference. The "improved" HbA1c subgroup experienced a more pronounced CST reduction at 2 months (p = 0.042), with outcomes leveling off with other groups by 12 months. Conclusively, DEX implant outcomes in DME were not influenced by either baseline HbA1c levels or their changes over time. This suggests that local alterations in the inflammation milieu may have a potentially stronger impact on DME treatment outcomes, highlighting the importance of considering local factors in DME treatment.

Proteomic analysis of aqueous humor reveals novel regulators of diabetic macular edema

Diabetic macular edema (DME) is the most common cause of blindness in patients with diabetic retinopathy. To investigate the proteomic profiles of the aqueous humor (AH) of individuals with diabetic macular edema (DME), AH samples were collected from patients with non-diabetes mellitus (NDM), DM, nonproliferative diabetic retinopathy (NPDR), and DME. We performed comparative proteomic analyses using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and bioinformatics analyses. We identified 425 proteins in these AH samples, of which 113 showed changes in expression in DME compared with NDM, 95 showed changes in expression in DME vs. DM, and 84 showed changes in expression in DME compared with NPDR. The bioinformatics analysis suggested that DME is closely associated with platelet degranulation, oxidative stress-related pathway, and vascular-related pathways. Upregulation of haptoglobin (HP) and downregulation of fibrillin 1 (FBN1) were validated by ELISA. Receiver operating characteristic (ROC) analysis showed that HP and FBN1 could distinguish DME from NPDR with areas under the curve of 0.987 (p = 0.00608) and 0.791 (p = 0.00629), respectively. The findings provide potential clues for further analysis of the molecular mechanisms and the development of new treatments for DME. HP and FBN1 may be potential key proteins and therapeutic targets in human DME. The proteomics dataset generated has been deposited to the ProteomeXchange/iProX Consortium with Identifier: PXD033404/IPX0004353001.

Ocular and Plasma Pharmacokinetics of Enavogliflozin Ophthalmic Solution in Preclinical Species

An enavogliflozin ophthalmic solution (DWRX2008) is being developed to treat diabetic retinopathy and macular edema. This study evaluated the ocular distribution and plasma pharmacokinetics (PKs) of enavogliflozin in animal species. A sample of [14C] enavogliflozin was ocularly administered to two rabbits per time point at single doses of 600 μg/eye to evaluate ocular PK, which was evaluated using autoradiography until 48 h post-dose. Plasma concentrations after ocular administration in six rabbits, three rats, and three beagle dogs with single doses of 400 μg, 25 μg, and 100 μg, respectively, were investigated for 24 h. The retinal concentration of [14C] enavogliflozin reached Cmax at 2.0 h with an elimination half-life of 32.5 h, which remained above the IC50 value of sodium-dependent glucose transporter 2 until 24 h post-dose. In the plasma of rabbits, the fastest Tmax of 0.5 h and a 3.6 h half-life were observed among animal species. The relative bioavailability in rabbits after ocular administration was 3.4 compared to oral administration. Ocular administration of enavogliflozin could be a potential therapeutic route for diabetic retinal complications, based on relative bioavailability and effective delivery to the posterior ocular segment. DWRX2008 would be applicable to humans with favorable PK profiles and minimal systemic adverse effect.

Optical coherence tomography in the management of diabetic macular oedema

Diabetic macular oedema (DMO) is the major cause of visual impairment in people with diabetes. Optical coherence tomography (OCT) is now the most widely used modality to assess presence and severity of DMO. DMO is currently broadly classified based on the involvement to the central 1 mm of the macula into non-centre or centre involved DMO (CI-DMO) and DMO can occur with or without visual acuity (VA) loss. This classification forms the basis of management strategies of DMO. Despite years of research on quantitative and qualitative DMO related features assessed by OCT, these do not fully inform physicians of the prognosis and severity of DMO relative to visual function. Having said that, recent research on novel OCT biomarkers development and re-defined classification of DMO show better correlation with visual function and treatment response. This review summarises the current evidence of the association of OCT biomarkers in DMO management and its potential clinical importance in predicting VA and anatomical treatment response. The review also discusses some future directions in this field, such as the use of artificial intelligence to quantify and monitor OCT biomarkers and retinal fluid and identify phenotypes of DMO, and the need for standardisation and classification of OCT biomarkers to use in future clinical trials and clinical practice settings as prognostic markers and secondary treatment outcome measures in the management of DMO.

Neuritin Alleviates Diabetic Retinopathy by Regulating Endoplasmic Reticulum Stress in Rats

BACKGROUND

Neuritin, a small-molecule neurotrophic factor, maintains neuronal cell activity, inhibits apoptosis, promotes process growth, and regulates neural progenitor cell differentiation, migration, and synaptic maturation. Neuritin helps retinal ganglion cells (RGCs) survive optic nerve injury in rats and regenerate axons. However, the role of Neuritin in Diabetic retinopathy (DR) is unclear.

OBJECTIVE

This study is intended to investigate the effect and mechanism of Neuritin in DR. For this purpose, we established DR rat models and injected Neuritin into them. This study provides a potential treatment for diabetic retinopathy.

METHODS

The rat model of DR was established by streptozotocin (STZ) injection, and the effect of Neuritin on DR was detected by intravitreal injection. Histological analysis was performed by H&E and TUNEL methods. The mRNA and protein expressions of endoplasmic reticulum stress (ERS) pathway-related transcription factors were detected by qRT-PCR and western blot. The blood-retinal barrier (BRB) function was assessed using the patch-clamp technique and Evans blue leakage assay.

RESULTS

Neuritin significantly improved the retinal structure, restrained the apoptosis of retinal cells, and protected the normal function of BRB in DR model rats. Mechanistically, Neuritin may function by inhibiting the expression of GRP78, ASK1, Caspase-12, VEGF, and so on.

CONCLUSION

Our results indicate that Neuritin alleviates retinal damage in DR rats via the inactive endoplasmic reticulum pathway. Our study provides a potential treatment for DR.

Advances in the engineering of the outer blood-retina barrier: From in-vitro modelling to cellular therapy

The outer blood-retina barrier (oBRB), crucial for the survival and the proper functioning of the overlying retinal layers, is disrupted in numerous diseases affecting the retina, leading to the loss of the photoreceptors and ultimately of vision. To study the oBRB and/or its degeneration, many in vitro oBRB models have been developed, notably to investigate potential therapeutic strategies against retinal diseases. Indeed, to this day, most of these pathologies are untreatable, especially once the first signs of degeneration are observed. To cure those patients, a current strategy is to cultivate in vitro a mature oBRB epithelium on a custom membrane that is further implanted to replace the damaged native tissue. After a description of the oBRB and the related diseases, this review presents an overview of the oBRB models, from the simplest to the most complex. Then, we propose a discussion over the used cell types, for their relevance to study or treat the oBRB. Models designed for in vitro applications are then examined, by paying particular attention to the design evolution in the last years, the development of pathological models and the benefits of co-culture models, including both the retinal pigment epithelium and the choroid. Lastly, this review focuses on the models developed for in vivo implantation, with special emphasis on the choice of the material, its processing and its characterization, before discussing the reported pre-clinical and clinical trials.

Use of Yamane technique for secondary intraocular lens implantation following open globe injury

A woman in her 50s presented with suspected open globe injury (OGI) of the right eye after being hit with a high velocity piece of plastic. Visual acuity at the time of presentation was counting fingers in the affected eye. Slit lamp examination revealed a full thickness laceration of the cornea and a traumatic cataract. Primary corneal repair was performed and the patient was left aphakic after cataract removal. Secondary intraocular lens placement was deferred for 2 years, after which time a scleral-fixated intraocular lens was implanted using the Yamane technique. Postoperative visual acuity of 20/50 was achieved, with the vision limited by persistent diabetic macular oedema. Thus, this case of successful implantation of a secondary lens using the Yamane technique in a patient with prior corneal laceration and traumatic cataract highlights that the Yamane technique can result in visual improvement in patients with prior OGI.

Association between resistivity index of central retinal artery and severity of diabetic retinopathy

Purpose

Diabetic retinopathy (DR) is a leading cause of ocular morbidity. Its progression depends mainly on retinal vasculature and ocular blood flow. Color Doppler imaging (CDI) is a noninvasive imaging technique that measures blood flow velocity. The resistivity index (RI), calculated by the CDI, reflects the vascular resistance distal to the measuring location. RI is independent of the doppler angle and position of the patient, making it a reliable and reproducible parameter. To the best of our knowledge, there is only one study in literature studying the association between resistivity index (RI) of the central retinal artery (CRA) and severity of DR.

Aim

To determine the association between RI of CRA and severity of DR. To determine the association between RI of CRA and spectral-domain optical coherence tomography (SD-OCT) biomarkers for DR.

Methods

Type II diabetics visiting our OPD underwent DR screening and were graded into three categories according to ETDRS classification which include Group A-No diabetic retinopathy (No DR), Group B-Nonproliferative diabetic retinopathy (Moderate-Severe-Very Severe NPDR), and Group C-Proliferative diabetic retinopathy (PDR). SD-OCT was performed. Ultrasonic color doppler imaging was done. RI of the CRA was noted. It was compared between the three groups and its association with severity of DR and OCT biomarkers (central subfield thickness, cube average thickness and ellipsoid zone disruption) was studied.

Results

56 eyes of 28 patients were included in our study with 20 in Group A,14 in Group B, and 22 in Group C. RI of CRA compared within groups showed statistically significant association with severity of DR (P < 0.001). The presenting BCVA (LogMar) showed positive correlation with RI in all groups. OCT biomarker central subfield thickness showed a positive correlation with RI in Groups A (P < 0.001) and B. Ellipsoid zone (EZ) disruption showed a statistically significant association with RI in Group C (P < 0.001).

Conclusion

The RI of CRA is a reliable biomarker for the assessment of the severity of DR. Patients with high RI of CRA had higher chances of EZ disruption and presented with poor visual acuity.

CD40 Ligand-CD40 Interaction Is an Intermediary between Inflammation and Angiogenesis in Proliferative Diabetic Retinopathy

We aimed to investigate the role of the CD40-CD40 ligand (CD40L) pathway in inflammation-mediated angiogenesis in proliferative diabetic retinopathy (PDR). We analyzed vitreous fluids and epiretinal fibrovascular membranes from PDR and nondiabetic patients, cultures of human retinal microvascular endothelial cells (HRMECs) and Müller glial cells and rat retinas with ELISA, immunohistochemistry, flow cytometry and Western blot analysis. Functional tests included measurement of blood-retinal barrier breakdown, in vitro angiogenesis and assessment of monocyte-HRMEC adherence. CD40L and CD40 levels were significantly increased in PDR vitreous samples. We demonstrated CD40L and CD40 expression in vascular endothelial cells, leukocytes and myofibroblasts in epiretinal membranes. Intravitreal administration of soluble (s)CD40L in normal rats significantly increased retinal vascular permeability and induced significant upregulation of phospho-ERK1/2, VEGF, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). sCD40L induced upregulation of VEGF, MMP-9, MCP-1 and HMGB1 in cultured Müller cells and phospo-ERK1/2, p65 subunit of NF-ĸB, VCAM-1 and VEGF in cultured HRMECS. TNF-α induced significant upregulation of CD40 in HRMECs and Müller cells and VEGF induced significant upregulation of CD40 in HRMECs. sCD40L induced proliferation and migration of HRMECs. We provide experimental evidence supporting the involvement of the CD40L-CD40 pathway and how it regulates inflammatory angiogenesis in PDR.

Development of diabetic macular oedema shows associations with systemic medication - An epidemiological study

PURPOSE

To identify associations between systemic drugs and the incidence of diabetic macular oedema (DME). Of interest was to find beneficial and/or deleterious associations of used drugs.

METHODS

A historic cohort design based on administrative data. Study population consisted of 150 353 individuals with diabetes. Endpoint event was the development of DME (ICD-10 H36.01), censoring events were death or study end December 2017. The follow-up started between 1997 and 2010. The systemic medication consisted of 95 substances. We constructed a nested case-control study design comparing 2630 cases with DME to 13 144 age- and sex-matched controls without DME. Results are reported as odds ratios (ORs) with 95% confidence intervals (CIs) based on conditional logistic regression models.

RESULTS

Incidence rate for DME was 1.80 per 1000 person-years (95% CI 1.73-1.87). In all, we observed a lower incidence rate of DME in females (IRR 0.57; 95% CI 0.52-0.62) compared to males. Exposure to hormone replacement therapy estradiol (OR 0.42; 0.25-0.68), temazepam (0.23; 0.08-0.62) and allopurinol (0.61; 0.43-0.86) were associated with lower risk of DME, while use of insulin or insulin analogue (3.30; 2.99-3.64), sulfonylureas (1.21; 1.05-1.40), diuretic furosemide (1.90; 1.61-2.24), calcium channel blocker amlodipine (1.53; 1.34-1.75), ACE inhibitors ramipril (1.66; 1.46-1.89) and enalapril (1.38; 1.16-1.64) were associated with an increased risk of DME.

CONCLUSIONS

Large-scale studies examining the incidence of DME are lacking. Our findings suggest that associations of systemic medications with the incidence of DME may shed light on the pathogenesis of complex DME, encouraging further studies.

Early Postoperative Changes in Macular Choroidal Thickness After Uncomplicated Phacoemulsification in Patients With and Without Glaucoma: A Swept-Source Optical Coherence Tomography Study

Purpose The objective of this study was to examine the impact of uncomplicated phacoemulsification on macular choroidal thickness (CT) within the first three postoperative months and to investigate its relationship with postoperative cystoid macular edema (CME) in both glaucomatous and healthy subjects, utilizing swept-source optical coherence tomography (SS-OCT). Methods The non-randomized prospective study involved 82 patients, selected via convenience sampling from the First Department of Ophthalmology, Medical School of Athens, "G. Gennimatas" Hospital, Athens, Greece, between May 2018 and May 2022, undergoing phacoemulsification and intraocular lens (IOL) implantation. The inclusion criteria encompassed patients aged 50 years or above, with or without glaucoma. Patients with ocular pathologies that could influence macula or CT measurements were excluded. Data collection focused on retinal and CT variables of the macular area, measured using SS-OCT. Baseline measurements were established preoperatively, with follow-up assessments at one week, one month, and three months postoperatively to monitor CT and macular edema onset. Results A total of 82 eyes from 82 patients with a mean age of 79.1±8.3 years were included. The study population was divided into a glaucoma group (n=28 eyes) and a control group (n=54 eyes). Our findings indicate a consistently significant increase in macular CT measurements one month after cataract surgery, observed in both glaucomatous and non-glaucomatous eyes. In the first postoperative week, statistically significant changes in CT were observed only in patients with CME. Subsequently, at one-month interval, both patient groups, those with and without CME, exhibited statistically significant changes in CT across all macular sectors. CME was detected in 10 out of 28 eyes in the glaucoma group and in 16 out of 54 eyes in the control group. When evaluating the impact of postoperative CME on groups of glaucomatous and non-glaucomatous eyes, it was observed that glaucomatous eyes exhibited a significantly larger magnitude of change in subfoveal CT (SFCT) (p=0.03) at one month (relative to baseline) compared to non-glaucomatous eyes. There was also a 31% increase in the odds of developing CME for glaucoma patients; this result was not statistically significant (odds ratio {OR}, 1.31; 95% confidence interval {CI}, 0.50-3.47; p=0.57). Conclusions During the early postoperative period, the study revealed a significant increase in CT at one month after phacoemulsification in both glaucomatous and non-glaucomatous eyes. When CME was present, a significantly more pronounced magnitude of change in SFCT was observed at one month in glaucomatous eyes, as opposed to non-glaucomatous eyes. This observation suggests a possible selective susceptibility of glaucomatous eyes in the early postoperative period that requires further research.

Serum apolipoprotein A1 and B are associated with 6-month persistent and incident diabetic macular oedema in type 2 diabetes

AIMS

To investigate the associations of baseline apolipoprotein A1 (ApoA1) and B (ApoB) levels with persistent and incident diabetic macular oedema (DMO) after 6 months of follow-up.

METHODS

This is a prospective cohort study of patients aged ≥30 years with untreated diabetic retinopathy. Examinations, fundus photography and spectral domain optical coherence tomography (SD-OCT) were assessed at baseline, 1, 3 and 6 months. Serum lipids and apolipoproteins were analysed at a pathology laboratory. DMO was confirmed using SD-OCT, classified as (1) incident DMO, (2) persistent DMO and (3) regressed DMO. Eye-specific data were used, controlling for covariates and cluster effect.

RESULTS

We recruited 53 patients but only 38 completed the study [(62 eyes), 20 eyes (32.3%) with DMO]. Higher quartile of ApoA1 was associated with lower risk of persistent/incident DMO (p for trend 0.02), while higher ApoB/A1 was associated with higher risk of persistent/incident DMO (p for trend 0.02). Every 10 mg/dL increase in ApoA1 levels was associated with lower risk of persistent/incident DMO (OR 0.69; 95% CI 0.49 to 0.92; p value 0.016), whereas every 0.2 increase in ApoB/A1 was significantly associated with higher risk of persistent/incident DMO (OR 1.4; 95% CI 1.1 to 1.9; p value 0.013) at the end of the study.

CONCLUSION

Individuals with diabetes with higher ApoA1 had lower risk of persistent/incident DMO and those with higher ApoB/A1 had higher risk of persistent/incident DMO at the end of 6 months. These suggest that serum ApoA1 and ApoB/A1 levels may be important risk factors for DMO and could be predictive of persistent/incident DMO despite anti-vascular endothelial growth factor treatment.

Mid-term safety and effectiveness of macular peeling one month after intravitreal dexamethasone implant for tractional diabetic macular edema

Macular peeling combined or followed by intravitreal dexamethasone implant (DEX-i) was recommended as an efficacy approach for tractional diabetic macular edema (tDME). Knowing the synergistic effect of cataract surgery and DEX-i one month earlier in eyes with DME, we compared Epiretinal Membrane/Inner Limiting Membrane (ERM/ILM) peeling preceded by DEX-i one month before versus ERM/ILM peeling alone for the treatment of tDME. A retrospective study on patients affected by tDME who underwent ERM/ILM peeling one month after DEX-i (n = 11; Group A) or ERM/ILM peeling alone (n = 10; Group B) was performed. Longitudinal comparison of best-correct visual acuity (BCVA), central retinal thickness (CRT), and intraocular pressure (IOP) between the time of surgery (T₀) and each time point (months 1,3,5,6) within and among the groups were assessed. To evaluate the repeated measurements of BCVA, CRT, and IOP, a linear mixed-effects model was used. In Group A, DEX-i significantly improved mean BCVA and CRT (P < 0.001) just after 1 month (T₀). After ERM/ILM peeling, mean BCVA and CRT significantly improved from month 1 in Group A and month 3 in Group B. Mixed model revealed a significant difference in BCVA (P ≤ 0.0001) and CRT (P ≤ 0.02) at different time-points among the groups with better results in Group A. Neither complications nor uncontrolled IOP increase was detected. ERM/ILM peeling confirmed its effectiveness in treating tDME. DEX-i performed one month before surgery seemed to be a safe approach and ensured a greater and faster recovery considering functional and tomographic parameters.

The 0.19-mg Fluocinolone Acetonide Intravitreal Implant Reduces Treatment Burden in Diabetic Macular Edema

PURPOSE

To assess treatment burden in patients with diabetic macular edema (DME) after the 0.19-mg fluocinolone acetonide (FAc) intravitreal implant (ILUVIEN).

DESIGN

Prospective and retrospective analyses of a 36-month, phase 4, open-label, observational study.

METHODS

Setting: Multicenter.

PATIENT POPULATION

Included patients had DME and previously received corticosteroid treatment without a clinically significant rise in intraocular pressure (IOP) (N = 202 eyes in 159 patients). Patients were not randomized.

OBSERVATION PROCEDURES

Prospective, observational treatment burden data were analyzed for their relationship to safety and functional efficacy outcomes across 36 months.

MAIN OUTCOME MEASURES

Outcomes included the mean number of yearly treatments, supplemental-free probability over time, best-corrected visual acuity, and monitoring of IOP-related events.

RESULTS

Over 36 months, the mean number of yearly treatments decreased from 3.5 before FAc to 1.7 after FAc; at 36 months, 68.3% of patients required 0 to 2 treatments per year. After FAc, the percentage of eyes requiring supplemental therapy decreased vs before FAc (P < .0001 for each). Through 36 months, 25% of FAc-treated eyes did not require supplemental treatment. At 36 months, mean best-corrected visual acuity increased by 4.5 letters vs a decline of 6.4 letters in the 36 months before FAc. IOP elevations >25 mm Hg occurred in 18.2% of eyes that did not receive supplemental treatment after FAc vs 27.2% of eyes that received supplemental treatments, which included additional intraocular steroids.

CONCLUSIONS

Over 36 months, the FAc implant is associated with improved visual outcomes and better disease control as measured by a significant reduction in yearly treatment burden in patients with DME.

Visual function and retinal morphological changes after single suprachoroidal delivery of fluocinolone acetonide (Iluvien®) implant in eyes with chronic diabetic macular edema

BACKGROUND

To assess the efficacy and safety of supra-choroidal (SC) Iluvien in the management of chronic diabetic macular edema (DME).

METHODS

A retrospective interventional non-comparative consecutive case series including patients with chronic DME who received an SC Iluvien implant. All patients had persistent central macular thickness (CMT) ≥ 300µ after previous treatment with anti-vascular endothelial growth factor (VEGF) agents or laser photocoagulation. The main outcome measures were improvement of best-corrected visual acuity (BCVA), reduction of CMT, and detection of ocular hypertension/glaucoma or cataract formation. Friedman's two-way ANOVA was used to analyze BCVA, intraocular pressure (IOP), and DME across different time points. P-value = 0.05.

RESULTS

The study included 12 eyes of 12 patients. Six patients (50%) were males. The median age was 58 years (range 52-76 years). The median duration of DM was 13 years (range 8-20 years). Ten patients (83.3%) were phakic and 2 patients (17%) were pseudophakic. The median pre-operative BCVA was 0.07 (range 0.05-0.8). The median pre-operative CMT was 544µ (range 354-745µ). The median pre-operative IOP was 17 mmHg (range 14-21mmHg). The median follow-up period was 12 months, range (12-42). Post-operatively, the median final BCVA was 0.15 (range 0.03-1), p 0.02, the median CMT was 404µ (range 213-747), p 0.4 and the median IOP was 19.5 mmHg (range 15-22), p 1. Two out of 10 phakic patients (20%) developed nuclear sclerosis grade I by 12 months. Six patients (50%) developed a transient rise in IOP < 10 mmHg from the baseline that resolved within 3 weeks with antiglaucoma drops.

CONCLUSION

SC Iluvien is potentially effective in improving visual function, reducing macular edema, and reducing the incidence of steroid-induced cataracts and glaucoma.

Persistent diabetic macular edema: Definition, incidence, biomarkers, and treatment methods

Intravitreal antivascular endothelial growth factor (anti-VEGF) treatment has drastically improved the visual and anatomical outcomes in patients with diabetic macular edema (DME); however, success is not always guaranteed, and a proportion of these eyes demonstrate persistent DME (pDME) despite intensive treatment. While standardized criteria to define these treatment-resistant eyes have not yet been established, many studies refer to eyes with no clinical response or an unsatisfactory partial response as having pDME. A patient is considered to have pDME if the retinal thickness improves less than 10-25% after 6 months of treatment. A range of treatment options have been recommended for eyes with pDME, including switching anti-VEGF agents, using corticosteroids and/or antioxidant drugs in adjunct with anti-VEGF therapy, and vitrectomy. In addition, multimodal imaging of DME eyes may be advantageous in predicting the responsiveness to treatment; this is beneficial when initiating alternative therapies. We explore the literature on persistent DME regarding its defining criteria, incidence, the baseline biological markers that may be useful in anticipating the response to treatment, and the available treatment options.

Diabetic Macular Oedema Guidelines: An Australian Perspective

The number of people living with diabetes is expected to rise to 578 million by 2030 and to 700 million by 2045, exacting a severe socioeconomic burden on healthcare systems around the globe. This is also reflected in the increasing numbers of people with ocular complications of diabetes (namely, diabetic macular oedema (DMO) and diabetic retinopathy (DR)). In one study examining the global prevalence of DR, 35% of people with diabetes had some form of DR, 7% had PDR, 7% had DMO, and 10% were affected by these vision-threatening stages. In many regions of the world (Australia included), DR is one of the top three leading causes of vision loss amongst working age adults (20-74 years). In the management of DMO, the landmark ETDRS study demonstrated that moderate visual loss, defined as doubling of the visual angle, can be reduced by 50% or more by focal/grid laser photocoagulation. However, over the last 20 years, antivascular endothelial growth factor (VEGF) and corticosteroid therapies have emerged as alternative options for the management of DMO and provided patients with choices that have higher chances of improving vision than laser alone. In Australia, since the 2008 NHMRC guidelines, there have been significant developments in both the treatment options and treatment schedules for DMO. This working group was therefore assembled to review and address the current management options available in Australia.

Focal Photocoagulation as an Adjunctive Therapy to Reduce the Burden of Intravitreal Injections in Macula Edema Patients, the LyoMAC2 Study

AIM

To assess the efficacy of focal photocoagulation of capillary macroaneurysms (CMA) to reduce the burden of intravitreal injections (IVI) in patients with macular edema (ME).

MATERIALS AND METHODS

Retrospective multicenter study in patients with diabetic ME or ME secondary to retinal vein occlusion (ME-RVO). CMA associated with ME were selectively photocoagulated. Patients were followed for one year after photocoagulation.

RESULTS

93 eyes of 76 patients were included in this study. At 6 months after the laser (n = 93), there was a significant decrease in mean macular thickness (from 354 µm to 314 µm, p < 0.001) and in mean IVI number (from 2.52 to 1.52 at 6 months, p < 0.001). The mean BCVA remained stable (0.32 and 0.31 logMAR at baseline and 6 months, p = 0.95). At 12 months (n = 81/93), there was a significant decrease in mean macular thickness (from 354 µm to 314 µm, p < 0.001) and in mean IVI number (from 4.44 to 2.95 at 12 months, p < 0.001), while the mean BCVA remained stable (0.32 and 0.30 logMAR at baseline and 12 months, p = 0.16).

CONCLUSION

Focal laser photocoagulation of CMA seems to be effective and safe for reducing the burden of IVI in patients with ME. Their screening during the follow-up should be considered closely.

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.

Impact of obstructive sleep apnea on the expression of inflammatory mediators in diabetic macular edema

PURPOSE

To determine differences in inflammatory markers expressed in diabetic macular edema (DME) patients with and without obstructive sleep apnea (OSA).

METHODS

This was a prospective, cross-sectional study. Patients with treatment naive DME were enrolled in the study. They were stratified into 2 groups based on Apnea Hypopnea Index (AHI) from overnight polysomnography: OSA + (AHI ≥ 15) and OSA - (AHI<15). Multiplex immunoassay was performed for aqueous and serum cytokines including VEGF, placental growth factor (PGF), ICAM, IL2, IL3, IL6, IL8, IL10, IL17, vascular cell adhesion molecule-1 (VCAM1), monocyte attractant protein-1 (MCP1), epidermal growth factor (EGF) and platelet derived growth factor (PDGF). Statistical significance was defined as p < 0.004 using Bonferroni correction.

RESULTS

32 DME positive patients were enrolled in the study; of which 17 patients were OSA + and 15 OSA-. The OSA + cohort had significantly higher levels of serum EGF (p = 0.003), and trended towards higher levels of most serum cytokines including ICAM and IL6. OSA- cohort had significantly higher levels of aqueous IL17 compared to the OSA + cohort (2.97 ± 1.7 vs. 1.4 ± 0.46 pg/mL, p = 0.004). There were no significant differences in other aqueous cytokines.

CONCLUSIONS

OSA + group trended towards higher levels of most serum inflammatory markers, suggesting a greater pro-inflammatory state. However, they did not have significantly greater level of aqueous cytokines.

Artificial intelligence in screening, diagnosis, and classification of diabetic macular edema: A systematic review

We review the application of artificial intelligence (AI) techniques in the screening, diagnosis, and classification of diabetic macular edema (DME) by searching six databases- PubMed, Scopus, Web of Science, Science Direct, IEEE, and ACM- from January 1, 2005 to July 4, 2021. A total of 879 articles were extracted, and by applying inclusion and exclusion criteria, 38 articles were selected for more evaluation. The methodological quality of included studies was evaluated using the Quality Assessment for Diagnostic Accuracy Studies (QUADAS-2). We provide an overview of the current state of various AI techniques for DME screening, diagnosis, and classification using retinal imaging modalities such as optical coherence tomography (OCT) and color fundus photography (CFP). Based on our findings, deep learning models have an extraordinary capacity to provide an accurate and efficient system for DME screening and diagnosis. Using these in the processing of modalities leads to a significant increase in sensitivity and specificity values. The use of decision support systems and applications based on AI in processing retinal images provided by OCT and CFP increases the sensitivity and specificity in DME screening and detection.

Diabetic Retinopathy – Diagnostics and Treatment Guidelines

Diabetic retinopathy is one of the most common complications of diabetes mellitus and represents a serious health, social and economic problem. With the expected increase in the number of patients with diabetes, it is becoming the leading cause of severe vision loss in the working-age population.  The presented guidelines summarize the current knowledge about this disease in order to standardize and update the procedures for the diagnosis, classification and treatment of diabetic retinopathy.

Sustained therapeutic effect of an anti-inflammatory peptide encapsulated in nanoparticles on ocular vascular leakage in diabetic retinopathy

Pigment epithelium-derived factor (PEDF), an endogenous Wnt signaling inhibitor in the serine proteinase inhibitors (SERPIN) super family, is present in multiple organs, including the vitreous. Significantly low levels of PEDF in the vitreous are found to associate with pathological retinal vascular leakage and inflammation in diabetic retinopathy (DR). Intravitreal delivery of PEDF represents a promising therapeutic approach for DR. However, PEDF has a short half-life after intravitreal injection, which represents a major hurdle for the long-term treatment. Here we report the prolonged therapeutic effects of a 34-mer peptide of the PEDF N-terminus, encapsulated in poly (lactic-co-glycolic acid) (PLGA) nanoparticles (PEDF34-NP), on DR. PEDF34-NP inhibited hypoxia-induced expression of vascular endothelial growth factor and reduced levels of intercellular adhesion molecule 1 (ICAM-1) in cultured retinal cells. In addition, PEDF34-NP significantly ameliorated ischemia-induced retinal neovascularization in the oxygen-induced retinopathy rat model, and significantly reduced retinal vascular leakage and inflammation in streptozotocin-induced diabetic rats up to 4 weeks after intravitreal injection, as compared to PLGA-NP control. Intravitreal injection of PEDF34-NP did not display any detectable toxicities to retinal structure and function. Our findings suggest that PEDF34-NP can confer sustained therapeutic effects on retinal inflammation and vascular leakage, having considerable potential to provide long-term treatment options for DR.

Comparison of intravitreal ranibizumab, aflibercept and bevacizumab therapies in diabetic macular edema with serous retinal detachment

Purpose

To compare the effects of ranibizumab, aflibercept and bevacizumab treatments in treatment-naive diabetic macular edema(DME) patients with serous retinal detachment(SRD).

Material and methods

This is a retrospective, comparative study. In a sample of 86 eyes of 86 untreated DME patients with accompanying SRD, 23 patients were treated with ranibizumab (IVR), 28 patients with aflibercept (IVA), and 35 patients with bevacizumab (IVB). All were injected intravitreally once a month for a 3-month loading dose. Subsequently, all participants were evaluated every months and if neccessary they received additional intravitreal treatments.Mean changes in best corrected visual acuity (BCVA), central retinal thickness (CRT), and SRD height over the 6-months study period were compared.

Results

At baseline, the groups did not differ in mean BCVA,CRT and SRD height. During the first 3 months, in IVA group the mean decrease in CRT and SRD height were significantly more than in the other two groups ( p < 0.05 for all). However, these differences disappeared at 6 months.The number of injections was similar between the groups during the study period.

Conclusion

In patients with DME accompanied by SRD, IVA is a more advantageous option in terms of reduction in CRT and SRD height from baseline to 3 months. In the 6-month period of treatment, IVR, IVA and IVB therapies areanatomically and functionally similar and significant effective modalities.