Laser treatment for diabetic macular edema in the 21st century

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.

Autonomous screening for laser photocoagulation in fundus images using deep learning

BACKGROUND

Diabetic retinopathy (DR) is a leading cause of blindness in adults worldwide. Artificial intelligence (AI) with autonomous deep learning algorithms has been increasingly used in retinal image analysis, particularly for the screening of referrable DR. An established treatment for proliferative DR is panretinal or focal laser photocoagulation. Training autonomous models to discern laser patterns can be important in disease management and follow-up.

METHODS

A deep learning model was trained for laser treatment detection using the EyePACs dataset. Data was randomly assigned, by participant, into development (n=18 945) and validation (n=2105) sets. Analysis was conducted at the single image, eye, and patient levels. The model was then used to filter input for three independent AI models for retinal indications; changes in model efficacy were measured using area under the receiver operating characteristic curve (AUC) and mean absolute error (MAE).

RESULTS

On the task of laser photocoagulation detection: AUCs of 0.981, 0.95, and 0.979 were achieved at the patient, image, and eye levels, respectively. When analysing independent models, efficacy was shown to improve across the board after filtering. Diabetic macular oedema detection on images with artefacts was AUC 0.932 vs AUC 0.955 on those without. Participant sex detection on images with artefacts was AUC 0.872 vs AUC 0.922 on those without. Participant age detection on images with artefacts was MAE 5.33 vs MAE 3.81 on those without.

CONCLUSION

The proposed model for laser treatment detection achieved high performance on all analysis metrics and has been demonstrated to positively affect the efficacy of different AI models, suggesting that laser detection can generally improve AI-powered applications for fundus images.

INDOCYANINE GREEN ANGIOGRAPHY-GUIDED PHOTOCOAGULATION OF LARGE MICROVASCULAR ABNORMALITIES ("TELCAPS") IN A PATIENT WITH PERSISTENT MACULA EDEMA IN THE CONTEXT OF RADIATION RETINOPATHY

PURPOSE

The purpose of this report is to describe a patient with radiation retinopathy who responded to indocyanine green angiography (ICGA)-guided photocoagulation as treatment for persistent macula edema secondary to TelCaps, a newly defined type of large microvascular abnormality.

METHODS

Retrospective case report.

RESULTS

A 40-year-old man with a history of bilateral retinoblastoma and right enucleation presented with decreased vision in the left eye secondary to macula edema. Examination revealed radiation retinopathy with a cluster of ICGA-avid large microaneurysms temporal to the macula. The patient did not respond to treatment with intravitreal bevacizumab or triamcinolone. Complete resolution of macula edema was demonstrated after two rounds of ICGA-guided focal photocoagulation to the aforementioned microaneurysm cluster. No subsequent or adjunctive intravitreal injections of anti-VEGF were required, and there was no recurrence of the TelCaps lesions at follow-up to eight years.

CONCLUSION

TelCaps are large microvascular abnormalities with high affinity for ICG. These lesions may not have been recognized because of difficulties in their detection on routine examination and with investigations including ocular coherence tomography angiogram and fluorescein angiogram. Early evidence supports their role in macula edema that is not responsive to intravitreal injections of anti-VEGF. ICGA-guided photocoagulation of TelCaps lesions can result in resolution of macula edema. To our knowledge, this is the first reported case of TelCaps secondary to radiation retinopathy.

Experimental and theoretical model of microvascular network remodeling and blood flow redistribution following minimally invasive microvessel laser ablation

Overly dense microvascular networks are treated by selective reduction of vascular elements. Inappropriate manipulation of microvessels could result in loss of host tissue function or a worsening of the clinical problem. Here, experimental, and computational models were developed to induce blood flow changes via selective artery and vein laser ablation and study the compensatory collateral flow redistribution and vessel diameter remodeling. The microvasculature was imaged non-invasively by bright-field and multi-photon laser microscopy, and optical coherence tomography pre-ablation and up to 30 days post-ablation. A theoretical model of network remodeling was developed to compute blood flow and intravascular pressure and identify vessels most susceptible to changes in flow direction. The skin microvascular remodeling patterns were consistent among the five specimens studied. Significant remodeling occurred at various time points, beginning as early as days 1-3 and continuing beyond day 20. The remodeling patterns included collateral development, venous and arterial reopening, and both outward and inward remodeling, with variations in the time frames for each mouse. In a representative specimen, immediately post-ablation, the average artery and vein diameters increased by 14% and 23%, respectively. At day 20 post-ablation, the maximum increases in arterial and venous diameters were 2.5× and 3.3×, respectively. By day 30, the average artery diameter remained 11% increased whereas the vein diameters returned to near pre-ablation values. Some arteries regenerated across the ablation sites via endothelial cell migration, while veins either reconnected or rerouted flow around the ablation site, likely depending on local pressure driving forces. In the intact network, the theoretical model predicts that the vessels that act as collaterals after flow disruption are those most sensitive to distant changes in pressure. The model results correlate with the post-ablation microvascular remodeling patterns.

Impact of COVID-19-related lifestyle changes on diabetic macular edema

AIM

To assess diabetic macular edema (DME) progression during the early phases of the COVID-19 pandemic, when severe societal restrictions raised the concern of possible deterioration of health in patients with systemic conditions, particularly those requiring frequent office visits.

METHODS

This is a multicenter retrospective chart review of 370 patients (724 eyes) with an established diagnosis of DME seen on 3 separate visits between January 2019 and July 2021. Period 1 was January 2019 to February 2020 (considered pre-COVID-19), period 2 was March 2020 to December 2020 (considered the height of the pandemic; highest level of pandemic-related clinical and societal regulations) and period 3 was January 2021 to July 2021 (re-adjustment to the new "pandemic norms"). Main outcome measures included visual acuity, body mass index (BMI), blood pressure (BP), hemoglobin A1c (HbA1c), macular thickness, patient adherence to scheduled ophthalmology visits, and DME treatment(s) received at each visit. To facilitate measurement of macular thickness, each macula was divided into 9 Early Treatment Diabetic Retinopathy Study (ETDRS)-defined macular sectors as measured by OCT imaging.

RESULTS

There was no change of BMI, systolic BP, and diastolic BP between any of the time periods. HbA1c showed a very small increase from period 1 (7.6%) to period 2 (7.8%, P=0.015) and decreased back to 7.6% at period 3 (P=0.12). Macular thickness decreased for 100% of macular regions. The central macular thickness decreased across all 3 periods from 329.5 to 316.6 µm (P=0.0045). After analysis of multiple variables including HbA1c, BMI, adherence to scheduled appointments, different clinic centers, and treatment interventions, there was no easily identifiable subgroup of patients that experienced the increase in DME.

CONCLUSION

DME doesn't worsen during the COVID-19 pandemic, instead sustaining a very small but statistically significant improvement. While identifying a mechanism behind our findings is beyond the scope of this study, potential explanations may include a delay in retinal changes beyond our study period, an unexpected increase in treatment frequency despite pandemic restrictions, and an unanticipated pandemic-related improvement in some lifestyle factors that may have had a positive impact on DME.

Experimental and Theoretical Model of Single Vessel Minimally Invasive Micro-Laser Ablation: Inducing Microvascular Network Remodeling and Blood Flow Redistribution Without Compromising Host Tissue Function

Overly dense microvascular networks are treated by selective reduction of vascular elements. Inappropriate manipulation of microvessels could result in loss of host tissue function or a worsening of the clinical problem. Here, experimental, and computational models were developed to induce blood flow changes via selective artery and vein laser ablation and study the compensatory collateral flow redistribution and vessel diameter remodeling. The microvasculature was imaged non-invasively by bright-field and multi-photon laser microscopy, and Optical Coherence Tomography pre-ablation and up to 30 days post-ablation. A theoretical model of network remodeling was developed to compute blood flow and intravascular pressure and identify vessels most susceptible to changes in flow direction. The skin microvascular remodeling patterns were consistent among the five specimens studied. Significant remodeling occurred at various time points, beginning as early as days 1-3 and continuing beyond day 20. The remodeling patterns included collateral development, venous and arterial reopening, and both outward and inward remodeling, with variations in the time frames for each mouse. In a representative specimen, immediately post-ablation, the average artery and vein diameters increased by 14% and 23%, respectively. At day 20 post-ablation, the maximum increases in arterial and venous diameters were 2.5x and 3.3x, respectively. By day 30, the average artery diameter remained 11% increased whereas the vein diameters returned to near pre-ablation values. Some arteries regenerated across the ablation sites via endothelial cell migration, while veins either reconnected or rerouted flow around the ablation site, likely depending on local pressure driving forces. In the intact network, the theoretical model predicts that the vessels that act as collaterals after flow disruption are those most sensitive to distant changes in pressure. The model results match the post-ablation microvascular remodeling patterns.

OCT-angiography based artificial intelligence-inferred fluorescein angiography for leakage detection in retina [Invited]

Optical coherence tomography angiography (OCTA) covers most functions of fluorescein angiography (FA) when imaging the retina but lacks the ability to depict vascular leakage. Based on OCTA, we developed artificial intelligence-inferred-FA (AI-FA) to delineate leakage in eyes with diabetic retinopathy (DR). Training data of 19,648 still FA images were prepared from FA-photo and videos of 43 DR eyes. AI-FA images were generated using a convolutional neural network. AI-FA images achieved a structural similarity index of 0.91 with corresponding real FA images in DR. The AI-FA generated from OCTA correctly depicted vascular occlusion and associated leakage with enough quality, enabling precise DR diagnosis and treatment planning. A combination of OCT, OCTA, and AI-FA yields more information than real FA with reduced acquisition time without risk of allergic reactions.

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

BACKGROUND

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

METHODS

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

DISCUSSION

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

TRIAL REGISTRATION

ClinicalTrials.gov NCT05728476. Registered on 15 February 2023.

Adjunct Nondamaging Focal Laser Reduces Intravitreal Injection Burden in Diabetic Macular Edema

This study aims to determine the impact of adjunct nondamaging focal laser therapy on the number of anti-vascular endothelial growth factor (anti-VEGF) injections and visual acuity (VA) and imaging in patients with diabetic macular edema (DME). A retrospective analysis of 18 eyes of 14 patients with DME treated with a single session of the PASCAL 532 nm Synthesis Photocoagulator with Endpoint Management was conducted. Demographic data, VA, imaging, laser parameters, and anti-VEGF injection burden six months before and after treatment were collected. Wilcoxon Signed-rank tests were used to assess changes in VA and injection burden before and after treatment. The mean number of intravitreal injections in the six-month period prior to laser treatment was 3.39 ± 2.57 injections compared to 2.33 ± 2.40 injections following laser treatment (p = 0.02). There was no significant difference between the mean VA on the day of treatment logMAR VA of 0.38 ± 0.27 (approx. Snellen equivalent 20/50) and the visual acuity on the most recent follow-up 6 months after laser logMAR VA of 0.35 ± 0.32 (approx. Snellen equivalent 20/40) (p = 0.34). There was also no significant difference in OCT central macular thickness before (311 μm) compared to 6 months after (301 μm, p = 0.64). Adjunct focal macular laser therapy is associated with a statistically and clinically significant decrease in the number of intravitreal injections required in the six-month period immediately following treatment, without compromising visual acuity or macular thickness. Nondamaging focal laser has the potential to alleviate the burden of injections for both patients and clinics.

Does HbA1c Level or Glomerular Filtration Rate Affect the Clinical Response to Endothelial Growth Factor Therapy (Ranibizumab or Aflibercept) in Diabetic Macular Edema? A Real-Life Experience

INTRODUCTION

Anti-vascular endothelial growth factor (VEGF) therapy is the first-line treatment for diabetic macular edema (DME). We investigated the effect of initial glycosylated hemoglobin (HbA1c) level and glomerular filtration rate (GFR) on treatment outcomes in patients with DME receiving anti-VEGF injections in routine clinical practice.

METHODS

A retrospective analysis of data from the prospective, multi-center, observational Fight Retinal Blindness! registry was performed. A total of 178 eyes with DME treated with anti-VEGF agents (ranibizumab or aflibercept) from 1 January 2010 to 31 March 2019 were enrolled in the analysis, with the long study period to allow for up to 24 months of follow-up. Data for eyes were tracked in the Fight Retinal Blindness! registry, and clinical parameters were collected by using local software. Changes in visual (best-corrected visual acuity [BCVA], in letters) and anatomic outcomes (central subfield thickness [CST], in microns) between subgroups of patients according to baseline HbA1c level (≤ 7% vs. > 7%) and GFR (> vs. ≤ 60 ml/min/m2 at 24 months were assessed.

RESULTS

The multivariate adjusted mean improvement in BCVA at 24 months of treatment was + 5.2 and + 6.8 letters in subgroups with baseline HbA1c level ≤ 7% and > 7%, respectively (p = 0.541), and + 6.9 and + 6.4 letters in subgroups with GFR > 60 and < 60 ml/min/1.73 m2, respectively (p = 0.852). The multivariate adjusted mean CST reduction was - 89.9 and - 76.4 µm in subgroups with baseline HbA1c level ≤ 7% and > 7%, respectively (p = 0.505), and - 85 and - 115 µm in subgroups with baseline GFR > 60 and ≤ 60 ml/min/1.73 m2, respectively (p = 0.130).

CONCLUSION

These results seem to indicate that visual and anatomical improvement in patients receiving intravitreal VEGF inhibitors for DME are independent of baseline HbA1c level and GFR, leading to the conclusion that high HbA1c levels or low GFR should not dictate injection timing in routine clinical practice. This study offers valuable insights for ophthalmologists, enabling a personalized treatment approach and optimizing DME patient outcomes.

Revisiting Retinal Degeneration Hallmarks: Insights from Molecular Markers and Therapy Perspectives

Visual impairment and blindness are a growing public health problem as they reduce the life quality of millions of people. The management and treatment of these diseases represent scientific and therapeutic challenges because different cellular and molecular actors involved in the pathophysiology are still being identified. Visual system components, particularly retinal cells, are extremely sensitive to genetic or metabolic alterations, and immune responses activated by local insults contribute to biological events, culminating in vision loss and irreversible blindness. Several ocular diseases are linked to retinal cell loss, and some of them, such as retinitis pigmentosa, age-related macular degeneration, glaucoma, and diabetic retinopathy, are characterized by pathophysiological hallmarks that represent possibilities to study and develop novel treatments for retinal cell degeneration. Here, we present a compilation of revisited information on retinal degeneration, including pathophysiological and molecular features and biochemical hallmarks, and possible research directions for novel treatments to assist as a guide for innovative research. The knowledge expansion upon the mechanistic bases of the pathobiology of eye diseases, including information on complex interactions of genetic predisposition, chronic inflammation, and environmental and aging-related factors, will prompt the identification of new therapeutic strategies.

Angiographic biomarkers are significant predictors of treatment response to intravitreal aflibercept in diabetic macular edema

This prospective single-center study aims to identify biomarkers that predict improvement in best-corrected visual acuity (BCVA) and central retinal thickness (CRT) at 6 months, in 76 eyes with diabetic macular edema (DME) treated monthly with intravitreal aflibercept. At baseline, all patients underwent standardized imaging with color photography, optical coherence tomography (OCT), fluorescein angiography (FA) and OCT angiography (OCTA). Glycosylated hemoglobin, renal function, dyslipidemia, hypertension, cardiovascular disease and smoking were recorded. Retinal images were graded in a masked fashion. Baseline imaging, systemic and demographic variables were investigated to detect associations to BCVA and CRT change post aflibercept. Predictors of BCVA improvement included greater macular vessel density quantified using OCTA (p = 0.001) and low-density lipoprotein (LDL) ≥ 2.6 mmol/L (p = 0.017). Lower macular vessel density eyes showed a significant reduction in CRT but no BCVA improvement. Predictors of CRT reduction included peripheral non-perfusion seen on ultrawide-field FA (p = 0.005) and LDL ≥ 2.6 mmol/L (p < 0.001). Retinal angiographic biomarkers derived from OCTA and ultrawide-field FA may help predict functional and anatomic response to anti-vascular endothelial growth factor (VEGF) therapy in patients with DME. Elevated LDL is associated with treatment response in DME. These results may be used to better-select patients who will benefit from intravitreal aflibercept for treatment of DME.

Optimizing treatment for diabetic macular edema during cataract surgery

Diabetic macular edema (DME) causes visual impairment in diabetic retinopathy (DR). Diabetes mellitus is a global epidemic and diabetic individuals are at risk of developing DR. Approximately 1 in 10 diabetic patients suffers from DME, which is the commonest cause of vision-threatening DR at primary-care screening. Furthermore, diabetes predisposes to a higher frequency and a younger onset of cataract, which further threatens vision in DME patients. Although cataract extraction is an effective cure, vision may still deteriorate following cataract surgery due to DME progression or recurrence, of which the risks are significantly higher than for patients without concurrent or previous history of DME at the time of operation. The management of pre-existing DME with visually significant cataract is a clinical conundrum. Deferring cataract surgery until DME is adequately treated is not ideal because of prolonged visual impairment and maturation of cataract jeopardizing surgical safety and monitoring of DR. On the other hand, the progression or recurrence of DME following prompt cataract surgery is a profound disappointment for patients and ophthalmic surgeons who had high expectations for postoperative visual improvement. Prescription of perioperative anti-inflammatory eye drops is effective in lowering the risk of new-onset DME after cataract surgery. However, management of concurrent DME at the time of cataract surgery is much more challenging because DME is unlikely to resolve spontaneously even with the aid of anti-inflammatory non-steroidal or steroid eye drops. A number of clinical trials using intravitreal injection of corticosteroids and anti-vascular endothelial growth factor (anti-VEGF) as first-line therapy have demonstrated safety and efficacy to treat DME. These drugs have also been administered perioperatively for the prevention of DME worsening in patients undergoing cataract surgery. This article reviews the scientific evidence to guide ophthalmologists on the efficacy and safety of various therapies for managing patients with DME who are particularly vulnerable to cataract surgery-induced inflammation, which disintegrates the blood-retinal barrier and egression of fluid in macular edema.

Advances in the treatment of intraocular malignancies: A literature review

Intraocular malignant tumors including primary and metastatic tumors, are mainly found in Retina and uvea, and very few cases originate from the sclera and optic nerve. Intraocular tumors can endanger the patient's vision and even life, and proper treatment is vital. There have been several traditional treatments for intraocular tumors, such as radiotherapy, chemotherapy and surgery. In recent years, new methods have been developed in clinical applications including anti-VEGF and gene therapy. This paper aims to provide a timely review about recent progress in the treatment of intraocular malignant tumor.

Intravitreal steroids compared to anti-vascular endothelial growth factor treatment for diabetic macular edema: a meta-analysis

TOPIC

Diabetic macular edema (DME) can be treated with either intravitreal anti-VEGF injections or intravitreal corticosteroid injections.

CLINICAL RELEVANCE

We provide an updated meta-analysis of the comparative efficacy and safety of intravitreal steroids and anti-VEGF agents for DME.

METHODS

A systematic search was performed on Ovid MEDLINE, Embase, and Cochrane Controlled Register of Trials from January 2005 to November 2021. Inclusion criteria included published randomized clinical trial data comparing the efficacy and safety of intravitreal steroids versus anti-VEGF agents for DME. Nonrandomized, noncomparative, and non-English studies were excluded.

RESULTS

Fourteen randomized clinical trials reporting on 827 eyes were included. Between these 2 treatments, our analysis revealed no significant difference in best-corrected visual acuity (BCVA) outcomes at 3 months (P = 0.11), 6 months (P = 0.21), 12 months (P = 0.24), and final follow-up (P = 0.91). Retinal thickness was significantly lower with steroid treatment at 3 months (P = 0.04), 6 months (P < 0.00001), and final follow-up (weighted mean difference = 39.99 μm; 95% confidence interval [CI] = 14.58,65.41; P = 0.002); however, there was no significant difference at 12 months (P = 0.18). Intravitreal anti-VEGF agents were associated with a lower incidence of intraocular pressure-related adverse events (risk ratio = 0.13; 95% CI = 0.05, 0.34; P < 0.00001). There was no significant difference between comparators for other adverse events, including cataract-related adverse events (P = 0.22).

CONCLUSIONS

Overall, intravitreal steroid treatment for DME was associated with no significant differences in BCVA, a significantly lower retinal thickness, and a higher risk of intraocular pressure-related events. The certainty of evidence ranged from low to moderate and the analysis was limited by heterogeneity. Our results reinforce the importance of a continual reevaluation of the role of intravitreal steroids in DME management.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Diabetic Macular Edema Treatment: Laser Photocoagulation Versus anti-VEGF Drugs

Abstract: Objective: The present study was aimed to compare best-corrected vision and central macular thickness for macular edema in diabetes (DME) after utilizing laser, Avastin, and Lucentis. Methods: A retrospective randomized cross-sectional study was conducted at Alfaisal Eye Center, Khartoum. Best-corrected vision and central macular thickness (CMT) were assessed by Snellen's chart and Heidelberg optical coherence tomography OCT, respectively. Results: In this study, a total of 252 records of DME-treated patients with laser applications, Avastin, and Lucentis were enrolled, their mean age was 57 ± 5.22 yrs. A significant enhancement in best-corrected vision and CMT of studied groups with laser applications, Avastin, and Lucentis was obtained (P= 0.000) with no differences between treated groups (p= 0.445 and 0,479), respectively. Non-significant differences in variable measurements related to gender or age (p = 0.117, 0.781), respectively. CMT of females (260 ± 48 μm) was thinner than males (306 ± 74 μm) after treatment (P = 0.000). Conclusion: laser applications, Avastin, and Lucentis improved best-corrected vision and reduced central macular thickness significantly with no clear differences between studied groups. Age or gender have a non-significant impact on dependent variables. Females gained thinner results compared to males after treatment.  

LUCENTIS IN THE TREATMENT OF DIABETIC MACULAR EDEMA, TWO-YEAR RESULTS

AIM

To evaluate, on the basis of two-year observations, the effectiveness of intravitreal treatment with Ranibizumab in patients with diabetic macular edema (DME) unresponsive to the previous laser treatment. Cohort and Methods: A retrospective study evaluates 29 eyes of 29 patients with diffuse DME unresponsive to their previous laser treatment. The group of the patients consisted of 16 males (55.1%) and 13 females (44.8%); their mean age was 71.3. The mean duration of diabetes mellitus was 13 years (3-20). 19 patients (65.5%) were treated with insulin, 10 patients (34.4%) were treated with peroral antidiabetics (PAD); the mean HbA1c value was 52 mmol/l. The treatment was started with 3 initial doses of intravitreal injections of Ranibizumab 0.5 mg. There was a one- -month interval between the applications. Subsequent evaluations and administrations of the following injections were made in the pro re nata (PRN) mode; the check-ups were carried out every month during the first year and on average every 3 months in the second year. The monitored parameters: the best corrected visual acuity (BCVA) measured on ETRDS (Early Treatment Diabetic Retinopathy Study) optotypes, the central retinal thickness (CRT). These parameters were monitored prior to the treatment and then in the 3rd, 6th, 9th, 12th, 18th and 24th months.

RESULTS

A statistically significant improvement in the mean value of BCVA was detected. From the initial 65.4 ±10.61 letters it improved by 11.2 letters (p.

Multicenter, Prospective, Randomized Study of Dexamethasone Intravitreal Implant in Patients with Center-Involved Diabetic Macular Edema in the Asia-Pacific Region

Purpose

To evaluate the safety and efficacy of dexamethasone intravitreal implant 0.7 mg (DEX) compared with laser photocoagulation in patients with diabetic macular edema (DME).

Patients and Methods

This Phase 3, multicenter, randomized, efficacy evaluator–masked, parallel-group, 12-month clinical study enrolled adults in China and the Philippines with reduced visual acuity secondary to fovea-involved DME in the study eye. Participants were randomized 1:1 to study eye treatment with laser photocoagulation every 3 months as needed (n = 139) or DEX every 5 months (n = 145). The main efficacy measures were best-corrected visual acuity (BCVA), central retinal thickness (CRT), and leakage area. The primary endpoint was the average change in BCVA from baseline over 12 months (area-under-the-curve method). Preplanned subgroup analyses evaluated outcomes in Chinese patients.

Results

Mean average change in BCVA from baseline during the study (letters) was 4.3 with DEX (n = 145) versus 1.4 with laser (n = 127) overall (P = 0.001) and 4.6 with DEX (n = 129) versus 0.6 with laser (n = 113) in Chinese patients (P < 0.001). At Month 12, mean change in CRT from baseline was −209.5 μm with DEX versus −120.3 μm with laser (P < 0.001) and mean change in total leakage area from baseline was −8.367 mm² with DEX versus −0.637 mm² with laser (P < 0.001). The most common treatment-emergent adverse events in the DEX group were increased intraocular pressure and cataract.

Conclusion

DEX administered every 5 months provided significantly greater improvement in BCVA, CRT, and total leakage area compared with laser treatment. DEX demonstrated an acceptable safety profile, consistent with an intraocular corticosteroid, and similar to that reported in completed global registration studies.

Laser Therapy in the Treatment of Diabetic Retinopathy and Diabetic Macular Edema

PURPOSE OF REVIEW

This review highlights indications and evidence on laser therapy in the management of diabetic retinopathy and diabetic macular edema. Particular focus is placed upon the benefits and limitations of conventional laser photocoagulation versus more modern laser photocoagulation techniques, as well as the role of laser photocoagulation in treatment of diabetic retinopathy and diabetic macular edema with the frequent utilization of pharmacologic, including anti-vascular endothelial growth factor (VEGF), therapy.

RECENT FINDINGS

Laser photocoagulation remains the gold-standard therapy for the effective, definitive treatment of PDR, and also is highly effective in the management of DME. However, numerous recent studies have demonstrated the clinical efficacy and improved functional and anatomic outcomes of combination therapy with pharmacologic treatment. Continuing innovations in laser technology and improved understanding of laser-retinal interactions and pathophysiology demonstrate that laser therapy will continue to play a critical role in the treatment of diabetic retinopathy and diabetic macular edema for many years to come.

The Effectiveness of Conbercept Combined with Panretinal Photocoagulation vs. Panretinal Photocoagulation in the Treatment of Diabetic Retinopathy: A Meta-Analysis

Objective

This meta-analysis aimed to compare the effect and safety of conbercept with panretinal photocoagulation (PRP) vs. PRP in the treatment of diabetic retinopathy (DR).

Methods

Relevant studies were identified through systemic searches of PubMed, EMBASE, China National Knowledge Infrastructure, and Wanfang database up to December 2020. The results of conbercept and PRP in patients with DR were analyzed, including overall effectiveness, best corrected visual acuity, central macular thickness, and complications.

Results

12 articles involving 1244 patients with DR were identified for this meta-analysis. The results of the meta-analysis showed that conbercept combined with PRP significantly increased the level of overall effectiveness and significantly reduced the central thickness of macula and the incidence of complications compared with the control group.

Conclusions

Conbercept with PRP tended to be more effective than PRP alone in terms of functional outcomes for treating DR.

Saudi Arabia Guidelines for diabetic macular edema: A consensus of the Saudi Retina Group

Diabetes mellitus (DM) and its complications are major public health burdens in Saudi Arabia. The prevalence of diabetic retinopathy (DR) is 19.7% and the prevalence of diabetic macular edema (DME) is 5.7% in Saudi Arabia. Diabetic macular edema is a vision-threatening complication of DR and a major cause of vision loss worldwide. Ocular treatments include retinal laser photocoagulation, anti-vascular endothelial growth factor (anti-VEGF) agents, intravitreal corticosteroids, and vitreoretinal surgery when necessary. The present consensus was developed as a part of the Saudi Retina Group's efforts to generate Saudi guidelines and consensus for the management of DME, including recommendations for its diagnosis, treatment, and best practice. The experts' panel stipulates that the treatment algorithm should be categorized according to the presence of central macula involvement. In patients with no central macular involvement, laser photocoagulation is recommended as the first-line option. Patients with central macular involvement and no recent history of cardiovascular (CVS) or cerebrovascular disorders can be offered anti-VEGF agents as the first-line option. In the case of non-responders (defined as an improvement of <20% in optical coherence tomography or a gain of fewer than 5 letters in vision), switching to another anti-VEGF agent or steroids should be considered after 3 injections. Within the class of steroids, dexamethasone implants are recommended as the first choice. In patients with a recent history of CVS events, the use of anti-VEGF agents is not recommended, regardless of their lens status. The experts' panel recommends that a future study be conducted to provide a cut-off point for early switching to steroid implants in pseudo-phakic eyes.

Burden of diabetic macular oedema in patients receiving antivascular endothelial growth factor therapy in South Korea: a healthcare resource use and cost analysis

OBJECTIVE

To examine healthcare resource utilisation (HRU) and direct medical costs for patients with diabetic macular oedema (DME) treated with antivascular endothelial growth factor (anti-VEGF) in Korea by comparing with those for (1) patients with diabetes mellitus (DM) without retinopathy and (2) patients with neovascular age-related macular degeneration (nAMD) treated with anti-VEGF.

DESIGN

Retrospective cohort study.

SETTING

The Korean National Health Insurance (NHI) database from 1 January 2014 to 31 December 2016.

PARTICIPANTS

We identified 1398 patients older than 30 years of age who received anti-VEGF treatment for DME in 2015 after excluding patients who had a diagnosis of nAMD in 2015 and any cancer in the preceding year.

MAIN OUTCOME MEASURES

One-year healthcare resource use and direct medical costs of patients with DME treated with anti-VEGF.

RESULTS

In total, 1398 patients with DME receiving anti-VEGF, 12 813 patients with DM without retinopathy and 12 222 patients with nAMD receiving anti-VEGF were identified. Hospital admissions and outpatient visits were highest in patients with DME, while the number of licensed anti-VEGF injections in those with DME was about half that of those with nAMD (2.1 vs 3.9 per patient per year). Mean 1-year medical costs were also higher in patients with DME (US$6723) than in those with DM without retinopathy (US$2687) and nAMD (US$4980). In a multivariable analysis with matched cohorts, DME was associated with 66% higher medical costs for comorbid diseases (adjusted OR (aOR), 1.66; 95% CI 1.45 to 1.90) and 50% lower anti-VEGF injections (aOR, 0.50; 95% CI 0.46 to 0.54) compared with nAMD.

CONCLUSIONS

The overall HRU and economic burden for DME treated with anti-VEGF were higher than for DM without retinopathy or for nAMD treated with anti-VEGF. Meanwhile, the lower number of licensed anti-VEGF injections compared with nAMD may reflect a potential lack of ophthalmological treatment for DME supported by the NHI in Korea.

Anatomical and functional outcomes of subthreshold micropulse laser versus intravitreal ranibizumab injection in treatment of diabetic macular edema

Background

To compare the therapeutic effects of subthreshold micropulse laser (SML) versus intravitreal injection of ranibizumab in treatment of diabetic macular edema (DME) both anatomically using optical coherence tomography (OCT) and functionally using best corrected visual acuity (BCVA) and multifocal electroretinogram (mfERG).

Methods

his study was an interventional prospective randomized comparative study. The study included 120 eyes classified into 3 groups: Group 1 included 40 eyes of 28 patients treated by SML laser, group 2 included 40 eyes of 32 patients treated by intravitreal injection of ranibizumab, and group 3 (control group for mfERG) included 40 eyes of 20 patients with diabetes mellitus (DM) of more than 10 year duration with no signs of diabetic retinopathy (DR). BCVA measurements, OCT and mfERG were done for the cases before and after interference and were followed up for 6 months

Results

By the end of the follow up period, BCVA significantly improved by 31% in group 1 vs 93% in group 2 with a statistically highly significant difference between the two groups (p value < 0.001). There was also a significant decrease in central subfield thickness in both groups with more reduction in group 2 compared with group 1 (p value < 0.001). There was a significant improvement in P1 amplitude of mf-ERG in group 2 (p value < 0.002) with no significant improvement in group 1. There was a significant decrease in P1 implicit time in group 2 (p value < 0.001) while there was no significant decrease in group1.

Conclusions

Intravitreal injection of ranibizumab is a superior treatment modality for DME compared with SML regarding both anatomical and functional outcomes.

Trial registration: This study has been approved by the local ethical committee of faculty of medicine of Minia University and retrospectively registered at the clinical trial gov. with Identifier: NCT04332133.

Biologic Therapy and Treatment Options in Diabetic Retinopathy with Diabetic Macular Edema

Proliferative diabetic retinopathy and diabetic macular edema can be a potentially sightthreatening disease if not treated correctly. It is directly correlated to the duration of diabetes and how well managed the patients' diabetes is. In the last 15 years, the treatment of diabetic eye disease has taken a quantum leap in methodology due to the group of biological agents named antivascular endothelial growth factor (anti-VEGF). The introduction of the first biological agent has revolutionized the treatment, not only in diabetic eye disease but also across most inflammatory eye diseases, causing leakage of fluid from the blood vessels i.e., in age-related macular degeneration. The availability of these biological agents, despite their considerable costs, have significantly improved the outcomes measured in visual acuity compared to more traditional treatments of diabetic retinopathy in the form of sole laser treatment and glycemic control. The agents demonstrate a favorable safety profile, but if the rarest and most severe side effects occur, there is a potential total loss of vision. This review aims to make an overview of the current pharmaceutical therapeutic options in the treatment of diabetic macular edema. This includes laser therapy, intravitreal steroids, and a primary focus on intravitreal antivascular endothelial growth factors.

Emerging corticosteroid delivery platforms for treatment of diabetic macular edema

INTRODUCTION

Diabetic macular edema (DME) is a leading cause of vision impairment. Low-grade inflammation is thought to play a critical role in its pathogenesis. Although vascular endothelial growth factor inhibitors are used first-line, not all eyes with DME respond optimally and may respond better to corticosteroids. Currently corticosteroids for DME are given intravitreally and require regular monitoring. There is an unmet need for longer lasting therapies and/or effective noninvasive therapies such as those given via oral or topical routes.

AREAS COVERED

This review discusses emerging corticosteroid delivery platforms for DME treatment. A literature search of investigational novel therapeutic steroid delivery platform in DME was conducted. Results are presented from preclinical, phase 1,2 & 3 clinical trials of various drug delivery systems using new technologies such as Solubilizing Nanoparticle technology, Mucus Penetrating Particles technology and Particle Replication In Non-wetting Templates. These new platforms aim to deliver corticosteroids effectively via topical, episcleral, subtenon, oral, and intravitreal routes.

EXPERT OPINION

These novel drug delivery platforms have the potential to lead to noninvasive or minimally invasive therapies and may overcome the shortcomings of current pharmacotherapy. However, larger comparative trials are needed for these agents to be added to the current armamentarium in DME management.

Treatment of Diabetic Macular Edema

PURPOSE OF REVIEW

Diabetes mellitus is a global epidemic which is growing in prevalence, and diabetic macular edema (DME) is a leading cause of visual impairment among patients affected by this disease. Our objective is to review current and upcoming therapeutic approaches to DME.

RECENT FINDINGS

Once considered the gold standard in treatment of DME, focal/grid laser is now reserved mostly for non-center-involving DME, while anti-vascular endothelial growth factor (anti-VEGF) therapy has become the first-line treatment. However, suboptimal responders to anti-VEGF and the burden of frequent injections have stimulated the development of novel approaches. Corticosteroids can be effective in treating DME, but adverse effects such as intraocular pressure elevation and cataract formation must be considered. Emerging therapeutics and drug delivery systems in the pipeline offer exciting potential solutions to this vision-threatening disease. Multiple types of therapeutics targeting various pathways implicated in the pathogenesis of DME may help lessen the global burden of vision loss from diabetes.

Handheld laser devices and laser-induced retinopathy (LIR) in children: an overview of the literature

Handheld laser devices are easily available to purchase through the internet and unregulated marketplaces at a relatively low cost. They are particularly attractive to children as they are seen as 'high tech', brightly coloured, and known to be able to burn holes in objects such as balloons. There is a widespread lack of knowledge about the risks of viewing the beam emanating directly from handheld lasers, and particularly those with high-output powers. The number of reported laser induced retinopathy (LIR) injuries in children is on the increase in the United Kingdom and represents a major public health issue. The number of individuals affected by LIR is likely to be underestimated owing to lack of presentation to health professionals, general poor awareness and non-reporting by children after the incident. The presentation of LIR is highly variable and dependent on many factors including type of laser, length of exposure and how it is administered. In this article, we review the features of retinal damage associated with inadvertent or deliberate laser administration using a handheld laser device. We highlight the importance of educating the wider public about this increasing problem; children who play with these devices are usually completely unaware of the long-term consequences of laser damage to the eye. It is also important that the features of LIR are recognised by health professionals involved in eye care as they can be mistaken for retinal dystrophies, particularly if the history of laser exposure is not volunteered or elicited.

The efficacy and safety of aflibercept and conbercept in diabetic macular edema

Diabetic macular edema (DME) has shown an increasing prevalence during the past years and is the leading cause of diabetic retinopathy blindness. Traditional treatment modalities include laser and corticosteroid therapy, which, however, either act through unclear mechanisms or cause cataracts and elevated intraocular pressure. In recent years, as the pathogenic role of VEGF in DME has been well-recognized, the intravitreal injection of anti-VEGF drugs has become the first-line treatment of DME due to their great efficacy in improving visual acuity and mitigating macular edema. Advantages have been shown for aflibercept and conbercept, the two recombinant decoy receptors that can bind VEGF with high specificity and affinity, in DME treatment in clinical trials conducted both worldwide and in People’s Republic of China. This review introduces the structural characteristics and molecular mechanisms of action of these two anti-VEGF drugs, and summarizes the clinical trials evaluating their efficacy and safety, with the hope to provide clues for designing optimal and personalized therapeutic regimens for DME patients.

ILUVIEN® technology in the treatment of center-involving diabetic macular edema: a review of the literature

Diabetic macular edema (DME) is one of the major causes of blindness, caused primarily by hyperglycemia and results from multiple pathological processes mostly secondary to increased levels of VEGF and other inflammatory cytokines. DME management includes control of systemic risk factors together with laser photocoagulation, frequent intraocular injections of anti-VEGF agents and steroids implants. Recent adoption of novel alternative drug delivery options has led to the development of sustained release ocular implants with longer duration of action with less injection frequency. This article will review the pharmacology and clinical data in terms of efficacy, safety and benefits of the sustained release steroid implants in treatment of DME with special emphasis on the fluocinolone acetonide ILUVIEN^® implant.

The RELATION study: efficacy and safety of ranibizumab combined with laser photocoagulation treatment versus laser monotherapy in NPDR and PDR patients with diabetic macular oedema

Purpose

To assess efficacy and safety of intravitreal ranibizumab 0.5 mg plus laser (COMBI) versus laser monotherapy (LASER) in patients with visual impairment due to diabetic macular oedema (DME) in either nonproliferative diabetic retinopathy (NPDR) or proliferative diabetic retinopathy (PDR) and to analyse the relevance of inner versus outer retinal thickness.

Methods

In this double‐masked, multicentre phase IIIb study, patients (N = 128) were randomized (2:1) to receive COMBI (n = 85) versus LASER (n = 43). Patients received four initial monthly injections of ranibizumab 0.5 mg (COMBI) or sham (LASER) followed by pro re nata (PRN) injections. In both groups, patients received laser at baseline and additional laser at 3 monthly intervals, as needed. The study was started in 2010 and was prematurely terminated due to approval of ranibizumab for DME.

Results

The least squares (LS) mean change in mean best‐corrected visual acuity (BCVA) from baseline to month 12 was higher in the COMBI (6.5) versus LASER (2.3) group (LS mean difference: 4.2 [95% CI 0.9; 7.4] letters, p = 0.01, primary end‐point). There was also a tendency in the same direction for the subgroup of 26 patients with PDR (LS mean difference 14.7, p = 0.11). Mean central retinal thickness decreased by 107.3 μm in the COMBI group and by 80.3 μm in the LASER group from baseline to month 12 (p = 0.28). Ranibizumab was well tolerated.

Conclusion

This study showed that ranibizumab plus laser is a valuable treatment option for the management of DME. Patients with DME in PDR might also benefit from combined therapy compared to laser alone.

Comparison of the Effect of Intravitreal Dexamethasone Implant in Vitrectomized and Nonvitrectomized Eyes for the Treatment of Diabetic Macular Edema

Purpose

To compare the effectiveness of sustained-release dexamethasone (DEX) intravitreal implant in nonvitrectomized eyes and vitrectomized eyes with diabetic macular edema (DME).

Methods

A retrospective review of the medical records of 40 eyes of 30 consecutive patients with diabetic macular edema who underwent intravitreal DEX implant injection. Patients were divided into 2 subgroups: 31 eyes that were nonvitrectomized (group 1) and 9 eyes that had previously undergone standard pars plana vitrectomy (group 2). The main outcome measures were BCVA and foveal thickness (FT).

Results

A significant improvement was seen in BCVA in both group 1 and group 2 at the 1st, 2nd, and 6th months after treatment with DEX implant (p < 0.05). In group 1, a significant reduction in FT was observed at the 1st, 2nd, and 6th months (p < 0.05). In group 2, a significant reduction in FT was seen at the 1st and 2nd months (p < 0.05), but the reduction rate at the 6th month after the injection was not statistically significant (p = 0.06).

Conclusion

DEX implant is effective for the treatment of diabetic macular edema, and the effectiveness of the drug is similar in vitrectomized and nonvitrectomized eyes.

Ranibizumab in Diabetic Macular Oedema - A Benefit-risk Analysis of Ranibizumab 0.5 mg PRN Versus Laser Treatment

INTRODUCTION

The structured Benefit-risk Action Team (BRAT) approach aims to assist healthcare decision makers in treatment assessments. We applied BRAT to compare the benefit-risk profile of ranibizumab 0.5 mg versus laser photocoagulation for the treatment of diabetic macular oedema (DMO).

METHODS

One-year data for the ranibizumab 0.5 mg pro re nata (PRN) and laser arms of the phase III trials RESPOND (NCT01135914; n=220), RESTORE (NCT00687804; n=345), and REVEAL (NCT00989989; n=396) were included in the analysis. The benefit measures included ≥10 letters gain/avoidance of loss in best-corrected visual acuity (BCVA), achieving central retinal thickness (CRT) <275 μm, and 25-item Visual Function Questionnaire (VFQ-25) outcomes. The risks measures included endophthalmitis, intraocular pressure increase, hypertension, proteinuria, arterial/venous thromboembolic events and deaths.

RESULTS

Ranibizumab treatment provided significant benefits compared with laser for ≥10 letter BCVA gain at month 12 (387/1,000 versus 152/1,000 patients), CRT <275 μm at 12 months (474/1,000 versus 348/1,000 patients), and improvement of ≥6.06 on the VFQ-25 near activities subscale (325/1,000 versus 245/1,000 patients). Results for the risk measures were similar for both treatments.

CONCLUSIONS

Superior clinically relevant outcomes were observed with ranibizumab 0.5 mg PRN compared with laser without compromising on safety. This analysis further supports the positive benefit-risk profile of ranibizumab 0.5 mg PRN.

Diabetic macular edema in proliferative stage treated with anti-vascular endothelial growth factor agent and triamcinolone acetonide by laser-based strategies

AIM

To appraise the effect of treatment for diabetic macular edema (DME) in proliferative stage with sufficient panrentinal photocoagulation (PRP) therapy and intravitreal injections (IV) Conbercept and posterior subtenon's triamcinolone acetonide (STTA) sequential therapy.

METHODS

This prospective clinical randomized controlled trial of cross-over design was conducted in three phases. The participants included cases of DME in proliferative stage. They were divided into two groups and treated with PRP before enrollment. Group A were treated with IV-Conbercept 0.5 mg for one month in the 1^st phase. Group B were treated with STTA 40 mg (twice per two weeks). The interventions were exchanged in the second phase (2mo) between the two groups. In the third phase (3-6mo) no other treatment was given. Best corrected visual acuity (BCVA), central macular thickness (CMT) measured by OCT and complications were compared.

RESULTS

After phase I: in Group A, BCVA improved from 0.201±0.17 to 0.37±0.24 (F=5.88, P=0.004). CMT changed from 449±155.10 to 304.1±84.70 µm (F=14.9, P<0.01). In Group B, BCVA changed from 0.195±0.19 to 0.26±0.20 (F=0.76, P=0.41) while CMT changed from 463.82±152.92 to 366.00±115.40 µm (F=3.70, P<0.03). The improvement of BCVA was better in Group A (P<0.05). After phase II: in Group A, BCVA raised to 0.47±0.27 (F=0.26, P<0.01), CMT reduced to 260.67±62.97 µm (F=-188.3, P<0.01); in Group B, BCVA raised to 0.51±0.26 (F=0.31, P<0.01), CMT reduced to 261.93±50.15 µm (F=-201.9, P<0.01). But there were no difference between two groups (P>0.05). After phase III: in Group A, BCVA maintained 0.42±0.25 (F=0.22, P=0.001), CMT maintained 267.8±58.34 µm, (F=-0.27, P<0.01); in Group B, BCVA was 0.47±0.25 (F=-0.27, P<0.01), CMT was 272.71±49.16 µm (F=-191.1, P<0.01). No serious complications happened in all phases.

CONCLUSION

PRP+Conbercept is better than PRP+STTA in DME with proliferative stage but PRP+Conbercept+STTA sequential therapy may be a wiser choice for persistent effectiveness on anatomical as well as functional status.

Clinical observation of the efficacy of Bevacizumab combined with argon green laser in treating fundus macular edema

We studied the clinical efficacy of Bevacizumab combined with argon green laser in treating fundus macular edema. From May 2009 to April 2013, 78 patients seeking treatment for macular edema in the First Affiliated Hospital of Nanchang University were enrolled in this study. Patients were randomly divided into two groups: i) The experimental group (n=39) and the control group (n=39). Patients in the experimental group were treated with Bevacizumab (Avastin^®) combined with argon green laser, and those in the control group were treated exclusively with argon green laser. Therapeutic effects were compared, and postoperative adverse reactions caused by both treatment methods were compared. Our results showed that, after treatment, the macular foveal thickness was reduced noticeably in both groups, while the therapeutic effect of combined treatment was more prominent. Patients in the experimental group gained the best-corrected visual acuity after one month of treatment, while patients in the control group achieved that after three months of treatment. We concluded that the use of Avastin^® combined with argon green laser was safe and effective. Visual acuity was improved obviously with minimum adverse reactions.

Considerations for management of patients with diabetic macular edema: Optimizing treatment outcomes and minimizing safety concerns through interdisciplinary collaboration

Diabetes is a growing worldwide epidemic and a leading cause of blindness in working-age people around the world. Diabetic retinopathy (DR) and diabetic macular edema (DME) are common causes of visual impairment in people with diabetes and often indicate the presence of diabetes-associated preclinical micro- and macrovascular complications. As such, patients with DR and DME often display complex, highly comorbid profiles. Several treatments are currently available for the treatment of DME, including anti-vascular endothelial growth factor (VEGF) agents, which are administered via intravitreal injection. While the safety profiles of approved ocular anti-VEGF therapies have been reassuring, the high-risk nature of the DME patient population means that treatment must be carefully considered and a holistic approach to disease management should be taken. This requires multidisciplinary, collaborative care involving all relevant specialties to ensure that patients not only receive prompt treatment for DME but also appropriate consideration is taken of any systemic comorbidities to evaluate and minimize potentially serious safety issues.

Combination of Anti-VEGF and Laser Photocoagulation for Diabetic Macular Edema: A Review

Diabetic macular edema (DME) is the most common cause of vision loss in diabetic patients. Thirty years ago, the Early Treatment Diabetic Retinopathy Study (ETDRS) demonstrated that focal/grid laser photocoagulation reduces moderate vision loss from DME by 50% or more; thus, macular photocoagulation became the gold standard treatment for DME. However, with the development of anti-VEGF drugs (bevacizumab, ranibizumab, and aflibercept), better outcomes were obtained in terms of visual acuity gain and decrease in macular thickness in some studies when antiangiogenic drugs were administered in monotherapy. Macular laser therapy may still play an important role as an adjuvant treatment because it is able to improve macular thickness outcomes and reduce the number of injections needed. Here, we review some of the clinical trials that have assessed the efficacy of macular laser treatment, either as part of the treatment protocol or as rescue therapy.

Clinical Characteristics of Patients with Newly Diagnosed Diabetic Macular Edema in Turkey: A Real-Life Registry Study-TURK-DEM

Purpose. To evaluate the clinical and diagnostic characteristics of patients with newly diagnosed diabetic macular edema (DME) in Turkey in a real-life setting. Methods. A total of 945 consecutive patients (mean (SD) age: 61.3 (9.9) years, 55.2% male) with newly diagnosed DME were included. Data on patient demographics, comorbidities, ocular history, ophthalmic examination findings including type of DME, central macular thickness (CMT) via time domain (TD) and spectral domain (SD) optical coherence tomography (OCT), and planned treatments were recorded. Results. OCT (98.8%) and fundoscopy (92.9%) were the two most common diagnostic methods. Diffuse and focal DMEs were detected in 39.2% and 36.9% of cases, respectively. Laser photocoagulation (32.1%) and antivascular endothelial growth factors (anti-VEGF; 31.8%) were the most commonly planned treatments. The median CMT in the right eye was significantly greater in untreated than in treated patients [376.5 μm (range: 160–840) versus 342 μm (range: 146–999) (p = 0.002)] and in the left eye [370 μm (range: 201–780) versus 329 μm (range: 148–999) (p < 0.001)]. Conclusions. This study is the first large-scale real-life registry of DME patients in Turkey. SD-OCT and fundoscopy were the most common diagnostic methods. Laser photocoagulation and anti-VEGF therapy were the most common treatments.

Laser thermal therapy monitoring using complex differential variance in optical coherence tomography

Conventional thermal therapy monitoring techniques based on temperature are often invasive, limited by point sampling, and are indirect measures of tissue injury, while techniques such as magnetic resonance and ultrasound thermometry are limited by their spatial resolution.  The visualization of the thermal coagulation zone at high spatial resolution is particularly critical to the precise delivery of thermal energy to epithelial lesions. In this work, an integrated thulium laser thermal therapy monitoring system was developed based on complex differential variance (CDV), which enables the 2D visualization of the dynamics of the thermal coagulation process at high spatial and temporal resolution with an optical frequency domain imaging system. With proper calibration to correct for noise, the CDV-based technique was shown to accurately delineate the thermal coagulation zone, which is marked by the transition from high CDV upon heating to a significantly reduced CDV once the tissue is coagulated, in 3 different tissue types ex vivo: skin, retina, and esophagus. The ability to delineate thermal lesions in multiple tissue types at high resolution opens up the possibility of performing microscopic image-guided procedures in a vast array of epithelial applications ranging from dermatology, ophthalmology, to gastroenterology and beyond.

Diabetic Macular Edema

Diabetic macular edema (DME), one the most prevalent causes of visual loss in industrialized countries, may be diagnosed at any stage of diabetic retinopathy. The diagnosis, treatment, and follow up of DME have become straightforward with recent developments in fundus imaging, such as optical coherence tomography. Laser photocoagulation, intravitreal injections, and pars plana vitrectomy surgery are the current treatment modalities; however, the positive effects of currently available intravitreally injected agents are temporary. At this point, further treatment choices are needed for a permanent effect.

Consumption of Polyphenol-Rich Zingiber Zerumbet Rhizome Extracts Protects against the Breakdown of the Blood-Retinal Barrier and Retinal Inflammation Induced by Diabetes

The present study investigates the amelioration of diabetic retinopathy (DR) by Zingiber zerumbet rhizome ethanol extracts (ZZRext) in streptozotocin-induced diabetic rats (STZ-diabetic rats). ZZRext contains high phenolic and flavonoid contents. STZ-diabetic rats were treated orally with ZZRext (200, 300 mg/kg per day) for three months. Blood-retinal barrier (BRB) breakdown and increased vascular permeability were found in diabetic rats, with downregulation of occludin, and claudin-5. ZZRext treatment effectively preserved the expression of occludin, and claudin-5, leading to less BRB breakdown and less vascular permeability. Retinal histopathological observation showed that the disarrangement and reduction in thickness of retinal layers were reversed in ZZRext-treated diabetic rats. Retinal gene expression of tumor necrosis factor-α, interleukin (IL)-1β, IL-6, vascular endothelial growth factor, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 were all decreased in ZZRext-treated diabetic rats. Moreover, ZZRext treatment not only inhibited the nuclear factor κB (NF-κB) activation, but also downregulated the protein expression of p38 mitogen-activated protein kinase (MAPK) in diabetic retina. In conclusion, the results suggest that the retinal protective effects of ZZRext occur through improved retinal structural change and inhibiting retinal inflammation. The antiretinopathy property of ZZRext might be related to the downregulation of p38 MAPK and NF-κB signal transduction induced by diabetes.

Perspective on the role of Ozurdex (dexamethasone intravitreal implant) in the management of diabetic macular oedema

Diabetic macular oedema (DMO) is the most common cause of visual loss in the working age population. Intravitreal therapy has superseded macular laser as the first-line treatment for the management of centre-involving DMO in most patients. As well as the proven efficacy of intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents, phase II and III clinical trials of Ozurdex intravitreal dexamethasone implants for DMO have also demonstrated a mean increase in visual acuity and corresponding mean reduction in central macular thickness, particularly in pseudophakic eyes. Because of the risk of visual loss from cataract, glaucoma and intraocular infection with the use of intravitreal steroids, Ozurdex tends to be reserved for use in patients unresponsive to anti-VEGF therapy for centre-involving DMO. Situations where Ozurdex may be considered a first-line treatment option for eyes with centre-involving DMO include pseudophakia, impending cataract surgery, or in the context of a recent arterial thromboembolic event. Because of their stable pharmacokinetics, Ozurdex slow-release implants may also be considered in vitrectomized eyes.

The ethanol extract of Zingiber zerumbet rhizomes mitigates vascular lesions in the diabetic retina

Diabetic retinopathy (DR) is a common diabetic eye disease which is well-known as the result of microvascular retinal changes. Although the ethanol extract from Zingiber zerumbet (L.) Smith rhizome (EEZZR) has been indicated to ameliorate hyperglycemia in diabetes, its protective effect on DR remains unclear. The aim of this study was to determine the effects of EEZZR on DR in streptozotocin (STZ) diabetic rats. Diabetic rats were treated orally with EEZZR (200, 300 mg/kg per day) or calcium dobesilate (CD; 500 mg/kg per day) for 12 weeks. EEZZR displayed similar characteristics to CD in reducing blood-retinal barrier permeability in diabetic rats. Retinal histopathological observation showed that retinal vessels were decreased in EEZZR-treated diabetic rats. EEZZR decreased the increased retinal expression of vascular endothelial growth factor (VEGF) and upregulate the expressions of renal pigment epithelium-derived factor (PEDF) in diabetic rats. Retinal mRNA expression of tumor necrosis factor-α, interleukin (IL)-1, IL-6, monocyte chemotactic proteins-1, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 were all decreased in EEZZR-treated diabetic rats. Moreover, EEZZR could attenuate phosphorylation of nuclear factor Kappa B (NF-κB) p65 and extracellular signal-regulated kinase (ERK)1/2 as well as inhibit the nuclear translocation of pNF-κB p65 induced by diabetes. In conclusion, restoring the balance between stimulators and inhibitors of angiogenesis may be associated with the protective effect of EEZZR on DR. In addition, EEZZR can ameliorate retinal inflammation via transrepression of NF-κB and inhibition of ERK1/2 signaling pathway.

What have we learnt about the management of diabetic macular edema in the antivascular endothelial growth factor and corticosteroid era?

PURPOSE OF REVIEW

To summarize the outcomes of the use of antivascular endothelial growth factor (anti-VEGF) agents and corticosteroids on the treatment paradigm for diabetic macular edema (DME).

RECENT FINDINGS

Favorable efficacy data along with acceptable long-term safety results of anti-VEGF agents have made them the standard first-line therapy in the management of DME. Level I evidence from large, multicenter clinical trials has established the beneficial role of anti-VEGF agents and intravitreal steroids. In addition, the role of anti-VEGF agents in the treatment of diabetic retinopathy has also been recently recognized. However, concerns such as suboptimal response, VEGF resistance, and long-term effects on retinal layers and vasculature have also been highlighted recently.

SUMMARY

The use of anti-VEGF agents and corticosteroids has revolutionized the management of DME. Despite the advantages including ease of administration, low incidence of adverse events, and concomitant improvement in retinopathy status, limitations of this therapeutic approach have been recognized. The current review will focus on the lessons learnt in the management of DME in the anti-VEGF and steroid era.

[Efficacy of dorzolamide in reducing retinal thickness after photocoagulation in diabetic macular oedema]

BACKGROUND

Focal photocoagulation interrupts vascular leakage in diabetic macular edema, and allows the retinal pigment epithelium to withdraw fluid that thickens the retina; this mechanism could be enhanced by dorzolamida, a topical carbonic anhydrase inhibitor.

OBJECTIVE

To determine the efficacy of dorzolamida compared against placebo, in reducing retinal thickness after focal photocoagulation, in eyes with diabetic macular oedema.

MATERIAL AND METHODS

Experimental, comparative, prospective, longitudinal, double blind study in diabetics with focal macular oedema treated with photocoagulation. Treated eyes were randomly assigned three weeks after the procedure to receive dorzolamide (group 1) or placebo (group 2), three times daily during three weeks. Means of visual acuity, center point thickness and macular volume were compared 3 and 6 weeks after photocoagulation within groups (Wilcoxon's t) and between groups (Mann-Whitneys's U).

RESULTS

Sixty-nine eyes form patients aged 58.3 ± 8.3 years; 37 were assigned to group 1 and 42 to group 2. Mean center point thickness changed from 178.4 ± 34μm to 170 ± 29.1μm in group 1 (p = 0.04), and from 179.2 ± 22.4μm to 178.6 ± 20.8μm in group 2 (p = 0.7); mean macular volume changed from 7.63 ± 0.52mm(3) to 7.50 ± 0.50mm(3) in group 1 (p = 0.02) and from 7.82 ± 0.43mm(3) to 7.76 ± 0.42mm(3) in group 2 (p = 0.014).

CONCLUSIONS

The efficacy of dorzolamide was higher than that of placebo, to reduce retinal thickness after focal photocoagulation in diabetics with macular oedema.

Dexamethasone Implants in Patients with Naïve or Refractory Diffuse Diabetic Macular Edema

PURPOSE

To assess the effect of dexamethasone (DEX) 0.7 mg (Ozurdex™) on refractory and treatment-naïve diffuse diabetic macular edema.

METHODS

A prospective study was conducted in 76 patients (40 refractory and 36 naïve) with visual acuities (VA) of 15-72 ETDRS letters, central macular thickness (CMT) >300 µm and intraocular pressure (IOP) <25 mm Hg. After the DEX implant (±photocoagulation), VA, CMT and total macular volume (TMV) were assessed monthly for 6 months.

RESULTS

At every visit, VA improved significantly from baseline (p < 0.001) in both groups, but values were significantly better in the naïve group, while CMT and TMV decreased significantly (p < 0.001) and similarly in both groups. The naïve group received more photocoagulations (p = 0.001). There were 7.9% transient IOP increases >10 mm Hg.

CONCLUSIONS

Substantial improvements in VA and CMT were achieved in both groups, and a gain of 1 ETDRS line was observed in the treatment-naïve group as compared to the refractory group, with a good safety profile in both.