Dexamethasone Intravitreal Implant for Chronic Diabetic Macular Edema Resistant to Intravitreal Bevacizumab Treatment

Switching to an Intravitreal Dexamethasone Implant after Intravitreal Anti-VEGF Therapy for Diabetic Macular Edema: A Review

Among working-age people, diabetic retinopathy and diabetic macular edema are currently considered the main causes of blindness. Nowadays, intravitreal injections are widely acknowledged as a significant milestone in ophthalmology, especially for the treatment of several retinal diseases, including diabetic macular edema. In particular, anti-vascular endothelial growth factor (VEGF) agents are typically the first line of treatment; however, monthly injections are required, at least, during the loading dosage. Notably, an intravitreal 0.7 mg dexamethasone (DEX) implant (Ozurdex®, AbbVie Inc., North Chicago, IL, USA) is considered a legitimate substitute treatment for diabetic eyes that have not responded to anti-VEGF treatment. In fact, clinical trials and real-life studies have demonstrated the effectiveness and safety of an intravitreal DEX implant in treating such conditions over a period of three to six months. For this reason, wisely selecting diabetic patients might be crucial to decreasing the load of injections in clinics and hospitals. The purpose of this review is to analyze the available scientific literature to highlight the benefits, efficacy, and clinical criteria for choosing whether to switch from intravitreal anti-VEGF therapy to an intravitreal DEX implant in diabetic macular edema.

A Review on Diabetic Retinopathy

Diabetic retinopathy is a well-recognised microvascular complication of diabetes and is among the leading cause of blindness all over the world. Over the last decade, there have been advances in the diagnosis of diabetic retinopathy and diabetic macular edema. At the same time, newer therapies for the management of diabetic retinopathy have evolved. As a result of these advances, a decline in severe vision loss due to diabetes has been witnessed in some developing countries. However, there is a steady increase in the number of people affected with diabetes, and is expected to rise further in the coming years. Therefore, it is prudent to identify diabetic retinopathy, and timely intervention is needed to decrease the burden of severe vision loss. An effort has been made to review all the existing knowledge regarding diabetic retinopathy in this article and summarize the present treatment options for diabetic retinopathy.

Safety and Efficacy of Dexamethasone Intravitreal Implant Given Either First-Line or Second-Line in Diabetic Macular Edema

Diabetic macular edema (DME) is a common sight-threatening complication of diabetic retinopathy (DR) and the leading cause of severe visual impairment among the working-age population. Several therapeutic options are available for the management of DME, including intravitreal corticosteroids. They have been traditionally used as second-line treatment, due to the risk of intraocular pressure increase and cataract-related adverse events. However, attention has recently been focused on the primary or early use of intravitreal corticosteroids, due to growing evidence of the crucial role of inflammation in the pathogenesis of DME. Furthermore, intravitreal steroid implants offer the additional advantage of a longer duration of action compared to anti-vascular endothelial growth factor agents (anti-VEGF). This review aims to summarize the available evidence on the efficacy and safety profile of dexamethasone (DEX) intravitreal implant, with a specific focus on clinical scenarios in which it might be considered or even preferred as first-line treatment option by adequate selection of patients, considering both advantages and possible adverse events. Patients with contraindications to anti-VEGF, DME with high inflammatory OCT biomarkers, pseudophakic patients and phakic patients' candidates to cataract surgery as well as vitrectomized eyes may all benefit from first-line DEX implant. Additionally, DME not responders to anti-VEGF should be considered for a switch to DEX implant and a combination therapy of DEX implant and anti-VEGF could be a valid option in severe and persistent DME.

Comparison of the efficacy of intravitreal Anti-VEGF versus intravitreal dexamethasone implant in treatment resistant diabetic Macular Edema

PURPOSE

Comparison of the efficacy of monthly anti-VEGF versus dexamethasone (DEX) implant in patients with diabetic macular edema (DME) whose macular edema persists despite three doses of anti-VEGF therapy.

MATERIALS AND METHODS

This retrospective study included 94 eyes of 94 patients with central macular thickness (CMT) > 300 μm despite previously receiving three doses of anti-VGEF (aflibercept or ranibizumab) injections between January 2014 and January 2019. The patients were divided into four groups. The first and second groups were the patients who received three more doses of initial anti-VGEF treatment after the initial anti-VGEF treatment. The third and fourth groups were patients switched to intravitreal dexamethasone implants. Patients were followed up every month for six months after the injection. The primary outcome measures were best-corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure (IOP) at six months.

RESULTS

The mean age of the patients included in the study was 64.64 ± 7; there were 58 men (61.7%) and 36 women (38.3%). There was no statistically significant difference between the groups regarding age, stage of retinopathy, and lens status. When CMT, BCVA, and IOP were assessed among the four groups at the end of the sixth month, no statistical difference between the groups was found. There was no need for medical intervention despite the statistically significant increase in IOP at the end of the sixth month compared to the third month in the dexamethasone implanted groups. In contrast to the decrease in CMT, which was statistically significant in all four groups at the end of the sixth month compared to the third month, the increase in BCVA was not statistically significant in any of the four groups at the end of the sixth month.

CONCLUSION

According to the results of our study, there is no superiority between continuing with existing anti-VEGF or switching to a dexamethasone implant after three doses of anti-VEGF.

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.

Effects of Smoking on Outcomes of Anti-Vascular Endothelial Growth Factor Therapy in Patients with Diabetic Macular Edema: A Retrospective Case-Control Study

PURPOSE

To determine the effect of smoking on the response to anti-vascular endothelial growth factor (anti-VEGF) therapy treatment in patients with diabetic macular edema (DME).

METHODS

This is a retrospective case - control study that included 60 eyes with DME. Smoking habits were obtained from hospital records and patient recall. Patients were divided into two groups: the ever-smoker group and the never-smoker group. All patients received Intravitreal ranibizumab with three loading doses followed by PRN protocol and all were followed up for at least 1 year. Outcome measures were best-corrected visual acuity (BCVA), central retinal thickness (CRT) at the fovea, and number of visits.

RESULTS

Smoking was not associated with worse posttreatment visual acuity and was not found to influence the change in ocular coherence tomography measurement of central macular thickness and the change in BCVA (posttreatment minus pretreatment). There were no statistically significant differences in the duration of treatment or number of visits between two groups of patients the ever-smoker group and the never-smoker group (P > 0.05).

CONCLUSION

In this study, smoking status did not influence the treatment outcome of anti-VEGFs; however, smoking should be encouraged due to its well-known other systemic unwanted effects.

Dexamethasone Intravitreal Implant for the Treatment of Macular Edema and Uveitis: A Comprehensive Narrative Review

Purpose

The purpose of this review article is to provide a comprehensive review of the current applications of intravitreal DEX implant (Ozurdex^®, Allergan Inc, Irvine, CA) for a variety of ophthalmic conditions – ranging from FDA approved indications to off-label uses. We have attempted to provide relevant evidence from the literature to help a reader develop an understanding of the biological and pharmacokinetic properties of DEX implant, its uses, and potential side effects.

Methods

PubMed searches were performed using the terms “Ozurdex”, or “intravitreal DEX implant”, AND “retinal vein occlusion”, or “diabetic macular edema”, or “uveitis”. The search was performed in July of 2021, with an additional search in October 2021. All original English language articles were considered for this review.

Results

DEX implant has evidence of efficacy in a variety of clinical situations including macular edema associated with retinal vein occlusion, diabetes, uveitis, and others. Safety concerns include cataract formation and progression, intraocular pressure elevation, complications related to intravitreal injection, and opportunistic infections secondary to steroid-induced immune suppression.

Conclusion

DEX implant is a useful tool in the management of several retinal disorders. Further studies are needed for head-to-head comparison with other treatment modalities and to determine its precise place in clinical practice.

Updates on the Current Treatments for Diabetic Retinopathy and Possibility of Future Oral Therapy

Diabetic retinopathy (DR) is a complication of diabetes and one of the leading causes of vision loss worldwide. Despite extensive efforts to reduce visual impairment, the prevalence of DR is still increasing. The initial pathophysiology of DR includes damage to vascular endothelial cells and loss of pericytes. Ensuing hypoxic responses trigger the expression of vascular endothelial growth factor (VEGF) and other pro-angiogenic factors. At present, the most effective treatment for DR and diabetic macular edema (DME) is the control of blood glucose levels. More advanced cases require laser, anti-VEGF therapy, steroid, and vitrectomy. Pan-retinal photocoagulation for non-proliferative diabetic retinopathy (NPDR) is well established and has demonstrated promising outcomes for preventing the progressive stage of DR. Furthermore, the efficacy of laser therapies such as grid and subthreshold diode laser micropulse photocoagulation (SDM) for DME has been reported. Vitrectomy has been performed for vitreous hemorrhage and tractional retinal detachment for patients with PDR. In addition, anti-VEGF treatment has been widely used for DME, and recently its potential to prevent the progression of PDR has been remarked. Even with these treatments, many patients with DR lose their vision and suffer from potential side effects. Thus, we need alternative treatments to address these limitations. In recent years, the relationship between DR, lipid metabolism, and inflammation has been featured. Research in diabetic animal models points to peroxisome proliferator-activated receptor alpha (PPARα) activation in cellular metabolism and inflammation by oral fenofibrate and/or pemafibrate as a promising target for DR. In this paper, we review the status of existing therapies, summarize PPARα activation therapies for DR, and discuss their potentials as promising DR treatments.

Efficacy and safety of single-dose dexamethasone implantation for patients with persistent diabetic macular edema: a systematic review and meta-analysis

PURPOSE

This meta-analysis was conducted to evaluate the efficacy and safety of single-dose dexamethasone implantation for treating persistent DME (diabetic macular edema) refractory to anti-VEGF (anti-vascular endothelial growth factor) drugs over a period of 6 months.

METHODS

All related clinical trials were reviewed by searching electronic databases of PubMed, Medline, Web of Science, Cochrane Library, and EMBASE. The primary outcome parameters were best-corrected visual acuity (BCVA) and central macular thickness (CMT). We performed this meta-analysis by using Stata15.0.

RESULTS

Ten clinical trials involving 362 eyes from 328 patients were eligible in the final analysis. After single-dose dexamethasone implantation, there was a significant improvement in BCVA from baseline to 1, 3, and 6 months with an average increase of - 0.15 logMAR (p < 0.001), - 0.14 logMAR (p < 0.001), and - 0.07 logMAR (p = 0.004), respectively. Further, mean CMT decreased significantly with an average reduction of 249.18 μm (p < 0.001), 217.66 μm (p < 0.001), and 91.56 μm (p < 0.001) at months 1, 3, and 6, respectively.

CONCLUSIONS

Our results indicate that switching to a dexamethasone implant could achieve significant anatomical and functional improvement among patients with refractory DME. Clinicians should be aware of this treatment option in refractory DME.

Short-Term Outcomes of Refractory Diabetic Macular Edema Switch From Ranibizumab to Dexamethasone Implant and the Influential Factors: A Retrospective Real World Experience

Introduction: To evaluate the effectiveness and safety of intravitreal dexamethasone (DEX) implants in refractory diabetic macular edema (DME) treated by intravitreal ranibizumab.

Materials and Methods: We retrospectively analyzed DME patients who received DEX implant treatment after being refractory to at least 3 monthly intravitreal ranibizumab injections. The main outcomes were best-corrected visual acuity (BCVA), central retinal thickness (CRT), and intraocular pressure (IOP).

Results: Twenty-nine eyes of 26 patients who had previously received an average of 8.1 ± 4.4 ranibizumab injections were included. Patients received between one and three DEX implants during 12.4 ± 7.4 months of follow-up. The mean final CRT significantly decreased from 384.4 ± 114.4 μm at baseline to 323.9 ± 77.7 μm (p = 0.0249). The mean final BCVA was 51.4 ± 21.3 letters, which was not significant compared to baseline (44.9 ± 30.2 letters, p = 0.1149). Mean IOP did not increase significantly. All patients tolerated the treatment well without serious adverse events. Higher baseline CRT and worse BCVA correlated with better therapeutic responses.

Conclusion: Switching to DEX implant is feasible and safe for treating patients of DME refractory to intravitreal ranibizumab in real world. Further larger-scale or multicenter studies would be conducted to explore different DEX treatment strategies for DME, such as first-line or early switch therapy, for better BCVA improvement.

Anti-VEGF-Resistant Retinal Diseases: A Review of the Latest Treatment Options

Anti-vascular endothelial growth factor (anti-VEGF) therapy currently plays a central role in the treatment of numerous retinal diseases, most notably exudative age-related macular degeneration (eAMD), diabetic retinopathy and retinal vein occlusions. While offering significant functional and anatomic benefits in most patients, there exists a subset of 15–40% of eyes that fail to respond or only partially respond. For these cases, various treatment options have been explored with a range of outcomes. These options include steroid injections, laser treatment (both thermal therapy for retinal vascular diseases and photodynamic therapy for eAMD), abbreviated anti-VEGF treatment intervals, switching anti-VEGF agents and topical medications. In this article, we review the effectiveness of these treatment options along with a discussion of the current research into future directions for anti-VEGF-resistant eyes.

Dril Influences Short-term Visual Outcome after Intravitreal Corticosteroid Injection for Refractory Diabetic Macular Edema

Purpose: Intravitreal injections (IVI) of anti-vascular endothelial growth factor (anti-VEGF) are considered the gold standard for diabetic macular edema (DME). Despite adequate anti-VEGF treatments, many patients present persistent DME. The aim of this study is to identify systemic, ocular and anatomical characteristics influencing functional and anatomical outcomes in refractory DME patients treated with IVI of corticosteroid.Materials and Methods: Retrospective multicenter hospital-based cohort study including type 2 diabetic adult patients with refractory DME that switched from intravitreal anti-VEGF to intravitreal corticosteroid between January 2017 and September 2018. Sociodemographic, clinical data, DME and treatment characteristics were collected at baseline (visit before switch), as well as spectral domain OCT features.Results: A total of 101 eyes were included. The median number of anti-VEGF injections before switch was 5.0 (min-max: 4.0-9.0) and the median anti-VEGF treatment duration before switch was 33.2 (min-max: 19.5-50.3) months. More than half of the patients (56; 54.9%) were diagnosed with diffuse DME. At baseline, 80 (88%) patients had cystoid DME, 55 (62.5%) patients had disorganization of retinal inner layers (DRIL) and 16 (17.6%) had subretinal fluid. Dexamethasone was the corticosteroid more commonly used (71.4%), followed by triamcinolone (24.4%) and fluocinolone (4.2%). Regarding best corrected visual acuity (BCVA), post-switch results showed no statistically significant improvement at three-month follow-up (p = .048/0.096), but the mean central macular thickness (CMT) decreased significantly from 486.3 (SD = 159) µm to 369.3 (SD = 129) µm at three-month follow-up (p < .001). DRIL was the tomographic characteristic able to influence significantly both CMT and BCVA final results (p = .02 and 0.012, respectively).Conclusions: Subfoveal DRIL on structural OCT was the DME factor influencing significantly clinical and imaging outcomes in refractory DME patients treated with intravitreal corticosteroid. Portuguese care trend towards DME shows preference for the use of dexamethasone implant after therapeutic failure with ranibizumab or bevacizumab injection.

Differential response to intravitreal dexamethasone implant in naïve and previously treated diabetic macular edema eyes

Background

To identify different response patterns to intravitreal dexamethasone implants (IDI) in naïve and previously treated (PT) diabetic macular edema (DME) eyes in a real-life setting.

Methods

342 IDI injections (203 DME eyes) were included. Number of IDI injections, percentage (%) of eyes with 1, 2, 3 and ≥ 4 injections, time to reinjections, visual acuity (VA), intraocular pressure (IOP) and central retinal thickness (CRT) were evaluated for naïve and PT DME eyes over 24 months.

Results

Mean number of injections was significantly lower in naïve vs PT DME eyes (1.40 ± 0.9 vs 1.82 ± 0.9, p < 0.001). The percentage of eyes receiving 1 injection was significantly higher in naïve vs PT DME eyes (76.1 vs 47.7), (p < 0.001). However, it was significantly lower for 2 (16.4 vs 29.4), or 3 injections (1.4 vs 17.6) (both p < 0.001), with no differences in eyes receiving ≥4 injections (5.9 vs 5.1 respectively, p = 0.80). Mean time to reinjection was not significantly different between both groups for the second, third and fourth injection (9.6 ± 4.0 vs 10.0 ± 5.5, p = 0.75, 13.2 ± 4.0 vs 16.0 ± 3.5, p = 0.21 and 21.7 ± 3.8 vs 19.7 ± 5.8, p = 0.55). VA scores were consistently better in naïve vs PT DME eyes at all studied timepoints, with no significant differences in CRT reduction or adverse effect rates.

Conclusion

Naïve DME eyes received lower number of IDI injections and showed better VA levels than PT DME eyes for 24 months in a real-world setting. This data supports the IDI use in early DME stages and provide further evidence of better IDI response when used as first-line therapy.

Comparison of Anatomical and Functional Outcomes of Intravitreal Dexamethasone Implant between Phakic and Pseudophakic Eyes with Diabetic Macular Edema

Purpose

To compare the effectiveness of dexamethasone (DEX) intravitreal implants for the treatment of diabetic macular edema between phakic and pseudophakic eyes after a follow-up.

Methods

A total of 79 eyes in 79 patients with diabetic macular edema who were insufficiently responsive to the previous anti-vascular endothelial growth factor treatment and applied intravitreal DEX implant were included in this retrospective study. The patients were divided into two groups according to their type of lenses: pseudophakic (group 1) and phakic (group 2). Best-corrected visual acuity, intraocular pressure (IOP), retinal nerve fiber layer thickness, and central macular thickness changes in the two groups were compared.

Results

Group 1 comprised 42 eyes in 42 patients with a mean age of 64.02 ± 3.79 years, while group 2 comprised 37 eyes in 37 patients with a mean age of 64.19 ± 5.08 years. In both groups, best-corrected visual acuity improved significantly with a significant decrease in central macular thickness (p < 0.001). In both lens types, the IOP values decreased significantly on the first day but subsequently increased significantly compared to baseline from one week to six months. Increases in IOP values were significantly higher in group 1 at the first week, 1st month, and 6th month compared with group 2. During follow-up, the inferior quadrant retinal nerve fiber layer showed a significant decrease in both groups.

Conclusions

In both phakic and pseudophakic eyes, intravitreal DEX implantation is an effective treatment method with low-risk complications. In our study, the pseudophakic group experienced a significantly earlier increase in IOP and at higher levels than did the phakic group. In light of these data, we suggest that in patients with pseudophakic eyes, follow-ups for IOP should be stricter and started earlier after intravitreal DEX treatment.

The effects of intravitreal injections on intraocular pressure and retinal nerve fiber layer: a systematic review and meta-analysis

The number of eye diseases treated with intravitreal injections is increasing. Obviously, an injection of fluid into the eye results in an increase of intraocular pressure (IOP), the main risk factor for glaucoma. However, the effect of these repeated IOP increases on the eye is unclear. Therefore, we performed a systematic review with meta-analyses. PubMed, Embase and Clinical Trials Registries were searched for articles investigating the relationship between intravitreal injections (anti-vascular endothelial growth factor [anti-VEGF] or steroids) and either IOP, retinal nerve fiber layer (RNFL)-thickness and glaucoma. Multiple meta-analyses were performed, combining data on intravitreal injection of anti-VEGF medication and dexamethasone implants. A total of 74 articles were eligible for meta-analyses. The short-term effect of an intravitreal injection of anti-VEGF showed a statistically significant increase in IOP. One day after injection of anti-VEGF, however, IOP was significantly lower than baseline. The long-term time-intervals showed no significant difference in IOP. After intravitreal injection of a dexamethasone implant, IOP was significantly higher than baseline 1 month post-injection. RNFL-thickness was significantly reduced 6 and 12 months post-injection of anti-VEGF, as well as at end of follow up. Caution is advised when using intravitreal medication, especially when treating patients with advanced glaucoma; in these cases, prophylactic IOP-lowering medication may be considered.

Intravitreal dexamethasone implant Ozurdex in the treatment of diabetic macular edema in patients not previously treated with any intravitreal drug: a prospective 12-month follow-up study

Objective: To evaluate the mid-long-term efficacy and safety of the dexamethasone intravitreal (DEX) implant (Ozurdex¹) in naïve patients with diabetic macular edema (DME).Methods: Prospective and single-center study conducted on consecutive patients with a diagnosis of DME, who received a DEX implant and were followed up for at least 12 months. The main outcomes measurements were the mean change in best corrected visual acuity (BCVA) and in foveal thickness (FT) as compared to the baseline values.Results: Of the 84 screened patients 50 were included in the study. The BCVA significantly improved from 52.4 (20.4) letters at baseline to 62.6 (15.6), 61.2 (18.4), 61.6 (18.6), 60.6 (19.0), and 60.6 (18.8) at 2, 4, 6, 12 months and end of follow-up period, respectively (repeated measures ANOVA and the Greenhouse-Geisser correction; p = .0008). At the end of the follow-up period, a gain of BCVA of ≥5, ≥10, and ≥15 letters were observed in 26 (52.0%), 18 (36.0%), and 16 (32.0%) patients, respectively. The mean FT was significantly reduced from 446.0 (139.9) µm at baseline to 327.2 (103.6) at the end of follow-up (repeated measures ANOVA and the Greenhouse-Geisser correction; p = .0008). During the study follow-up, the patients receive a mean of 3.4 (2.9-3.9) implants. Of the 32 phakic eyes at baseline, 17 (53.1%) either developed new lens opacity or progression of an existing opacity.Conclusion: In eyes with DME not previously treated with intravitreal drugs, DEX implants provide meaningful functional and anatomical benefits, and these results are sustained mid-long-term.

Anatomical and functional changes after dexamethasone implant and ranibizumab in diabetic macular edema: a retrospective cohort study

AIM

To investigate the efficacy and safety of ranibizumab (RZB group) and dexamethasone implant (DEX group) intravitreal treatments in patients with treatment-naïve center involved diabetic macular edema (DME) by means of functional and morphological assessments.

METHODS

This retrospective cohort study included 50 eyes of 50 patients with DME treated either with RBZ or DEX. Best-corrected visual acuity (BCVA) and microperimetry were evaluated at baseline and during a 6-month follow-up. In addition, central macular thickness (CMT) by means of structural optical coherence tomography (OCT) and retinal capillary plexus density and choriocapillary density by means of OCT angiography were assessed in all cases.

RESULTS

Functional and morphological parameters significantly improved during the study period in both groups. BCVA improved significantly in both groups with a greater increase in the DEX group compared to the RBZ group (P=0.030). Microperimetry significantly differed during follow-up between the two treatments (P=0.031). In both groups CMT significantly decreased (P<0.001) without statistically significant differences between the two groups. A statistically significant increase of deep capillary plexus density was detected in both groups at 30d after therapy. The retreatment rate was 0.70±0.10 and 0.65±0.10 in the RBZ group and 0.65±0.10 and 0.50±0.11 in DEX group at 120 and 180d respectively. Two out of 25 patients in DEX group showed intraocular pressure increase requiring hypotonic eye drops.

CONCLUSION

Both treatments are very effective for DME treatment during 6mo of follow-up with a lower retreatment rate in DEX group.

First-line treatment algorithm and guidelines in center-involving diabetic macular edema

Management of center-involving diabetic macular edema represents a real therapeutic challenge. Diabetic macular edema is the leading cause of visual acuity impairment in diabetic patients. Since the advent of intravitreal drugs, management of diabetic macular edema has significantly evolved. The historical grid laser photocoagulation is no longer recommended as first-line treatment of diabetic macular edema owing to the findings of the pivotal randomized controlled trials, and anti-vascular endothelial growth factor therapy has emerged as first-line therapy. Steroids also represent a valid treatment option in the management of naïve diabetic macular edema and their efficacy has also been confirmed in several studies. The optimal treatment for diabetic macular edema should consider both general and ophthalmological comorbidities. Patient compliance and motivation should also be carefully evaluated as some treatments require monthly follow-up. Based on recent literature evidence, the present review provides clinicians with a first-line treatment algorithm for center-involving diabetic macular edema tailored to the patient’s individual characteristics.

Dexamethasone Implant in Patients with Diabetic Macular Edema Resistant to Anti-VEGF Therapy

Objectives:

To investigate the efficacy of single dose intravitreal dexamethasone implant in patients with diabetic macular edema (DME) resistant to anti-VEGF therapy.

Materials and Methods:

Twenty eyes of 14 patients (8 male, 6 female; mean age, 65±5.7 years) with DME resistant to intravitreal ranibizumab injections were studied. A single intravitreal dexamethasone implant was injected into each eye and patients were followed up for 6 months. Response to therapy was assessed monthly by measuring intraocular pressure (IOP), best-corrected visual acuity (BCVA), and central foveal thickness (CFT).

Results:

Baseline (before injection) IOP was 14.9±2.7 mmHg and did not change significantly in the six months following injection. Baseline BCVA was 1.04±0.35 LogMAR and improved to 0.86±0.31 at month 1 without statistical significance (p=0.056). CFT was significantly lower in all monthly measurements compared to its baseline value of 682.2±229.2 μm. During the follow-up period, endophthalmitis, significant cataract, or rhegmatogenous retinal detachment were not detected.

Conclusion:

Intravitreal dexamethasone implant injection is associated with significant CFT reduction for up to six months without causing any complications. Although BCVA did not improve in parallel with the CFT reduction, intravitreal dexamethasone implant should be considered as an effective and safe treatment option in the management of DME patients resistant to anti-VEGF injections.

Intravitreal dexamethasone implant Ozurdex® in naïve and refractory patients with different subtypes of diabetic macular edema

Background

Diabetic macular edema (DME) can be treated with different alternatives, among them Dexamethasone intravitreal implant 0.7 mg (DEX 0.7) has demonstrated that may improve both central macular thickness (CMT) and best corrected visual acuity (BCVA). This study aimed to evaluate the effect of the intravitreal dexamethasone implant Ozurdex® in patients with different subtypes of diabetic macular edema over a 6-month follow-up period.

Methods

Eighty-four (29 naïve and 55 previously treated) eyes were included in this retrospective study. For each patient, the BCVA [Early Treatment Diabetic Retinopathy Study (ETDRS) charts] and macular thickness on optical coherence tomography (OCT) at baseline visit and within the 2nd, 4th, and 6th months of follow-up were obtained. The main outcomes measurements were the mean change in BCVA and in CMT with respect to the baseline value. The percentage of patients gaining ≥5 letters and ≥ 10 letters in BCVA was also analyzed. Results: A total of 84 eyes, 29 (34.5%) naïve and 55 (65.5%) non-naïve, from 69 patients were included in the study. BCVA at baseline was 58.8 (16.4) and 61.8 (11.6) in naïve and refractory patients, respectively, p = 0.4513. At every visit, BCVA significantly improved from baseline in naïve and non-naïve eyes (p < 0.0001 and p = 0.0003, respectively; Friedman rank sum test). At baseline, the mean CMT was 466.2 (189.7) μm and 448.1 (110.7) μm in the naïve and non-naïve patients, respectively (p = 0.5830); and decreased to 339.3 (92.5) μm and 357.5 (79.1) μm, respectively (p = 0.0004 and p < 0.0001, respectively, Wilcoxon signed-rank test). The proportion of patients gaining ≥10 letters was significantly greater in the naïve group, p = 0.0199.

Conclusion

The intravitreal dexamethasone implant (Ozurdex) is effective for the treatment of diabetic macular edema, even in refractory cases that have failed to respond to previous therapies.

Pharmacological Management of Diabetic Macular Edema in Real-Life Observational Studies

OBJECTIVES OF THE STUDY

of observational studies concerning the pharmacological management of diabetic macular edema (DME).

METHODS

A literature review was conducted using the PubMed database on 1 February 2018 to identify studies evaluating the efficacy of anti-VEGF and dexamethasone (DEX) implants for DME. Studies with more than 10 patients and follow-up of more than 6 months were selected. Analyses were carried out on the overall population and on subgroups defined according to baseline visual acuity (BVA) and the patients' naïve or non-naïve status.

RESULTS

Thirty-two studies evaluating the efficacy of anti-VEGF and 31 studies evaluating the efficacy of DEX-implants were retained, concerning 6,842 and 1,703 eyes, respectively. A mean gain of +4.7 letters for a mean of 5.8 injections (mean follow-up: 15.6 months) and +9.6 letters for a mean of 1.6 injections (10.3 months) was found in the anti-VEGF and DEX-implant studies, respectively. Final VA appears to be similar for both treatment (62 letters for anti-VEGF, 61.2 letters for DEX-implant), and BVA appears lower for DEX-implant, which may partially explain the greater visual gain. The DEX-implant studies show greater gains in VA compared to the anti-VEGF studies, especially for higher BVA. Indeed, mean gains for the subgroups of patients with BVA<50 letters, 5060 letters are +4.3, +5.8, and +3.1 letters, respectively, in the anti-VEGF studies and +10.5, +9.3, and +8.8 letters, respectively, in the DEX-implant studies. Regarding the patient's initial status, only naïve status appears to confer the best functional response in DEX-implant studies.

CONCLUSION

Observational studies investigating DEX-implant report clinically similar final VA when compared to anti-VEGF, but superior visual gains in real-life practice. This latter difference could be due to the better BVA, but also to the fact that less injections were administered in the anti-VEGF observational studies than in the interventional studies.

INTRAVITREAL DEXAMETHASONE IMPLANTATION IN PATIENTS WITH DIFFERENT MORPHOLOGICAL DIABETIC MACULAR EDEMA HAVING INSUFFICIENT RESPONSE TO RANIBIZUMAB

PURPOSE

To evaluate the effectiveness of a single intravitreal injection of dexamethasone implant in resistant diabetic macular edema that have different morphological types.

METHODS

In this retrospective study, 31 patients (35 eyes) with persistent diabetic macular edema, who underwent a single injection of dexamethasone implant, were evaluated. Diabetic macular edema was classified into three types: diffuse retinal thickening (n = 10), cystoid macular edema (n = 13), and serous retinal detachment (n = 12). Primary outcome measures were best corrected visual acuity, and central macular thickness.

RESULTS

The three subgroups were similar in terms of age and gender (P > 0.05). Total duration of diabetes was significantly less in the serous retinal detachment subgroup (P = 0.01). There were no differences in the best corrected visual acuity between the three subgroups until the sixth month. However, the best corrected visual acuity was significantly better in the diffuse retinal thickness subgroup at the sixth month (P = 0.008). Regarding the central macular thickness values, it was statistically better in serous retinal detachment than in diffuse retinal thickening and cystoid macular edema subgroups till the sixth month (P = 0.001). However, at the sixth month, there was not any statistical difference between subgroups regarding central macular thickness values. Antiglaucomatous agents were required in 4 (11.4%) patients throughout the study.

CONCLUSION

Treatment algorithms should differ according to the morphology of diabetic macular edema; however, more data is needed to give specific recommendations.

Repeated Dexamethasone Intravitreal Implant for the Treatment of Diabetic Macular Oedema Unresponsive to Anti-VEGF Therapy: Outcome and Predictive SD-OCT Features

PURPOSE

To investigate dexamethasone intravitreal implant 0.7 mg (DEX implant) for the treatment of diabetic macular oedema (DME) refractory to anti-vascular endothelial growth factor (anti-VEGF) therapy and evaluate predictive factors.

METHODS

Two-centre retrospective interventional case series, including 40 eyes of 31 patients treated with DEX implant for at least 2 consecutive cycles.

RESULTS

Mean ± SD intervals from implantation to recurrence in the first (4.2 ± 1.0 months) and second cycles (4.0 ± 0.9 months) were not significantly different. Best corrected visual acuity improved significantly (p < 0.001) by 7.0 ± 8.4 letters from baseline to month 2, and by 5.1 ± 6.9 letters between the first and second cycles. Central retinal thickness reduction 2 months after implantation was greater after the first (-194 ± 172 µm) than the second cycle (-134 ± 150 µm). Ellipsoid zone-external limiting membrane (EZ-ELM) disruption score decreased from 1.39 ± 1.16 at baseline to 1.24 ± 1.16 (p = 0.0832) after cycle 1 and remained stable 2 months after cycle 2. Eyes with persisting severe EZ-ELM disruption (score >2, n = 10) 2 months after the first DEX implant showed significantly (p = 0.0153) smaller visual acuity (VA) gains than eyes with less severe (score ≤2) EZ-ELM disruption.

CONCLUSION

Repeated intravitreal DEX injections with average intervals of 4 months are valuable in patients with DME refractory to anti-VEGF therapy. Disorganization of outer retinal layers (EZ-ELM) may predict smaller VA gains if evaluated after initial reduction of macular oedema.

A novel and less invasive technique to assess cytokine profile of vitreous in patients of diabetic macular oedema

PurposeA pilot study to validate the collection of vitreous reflux (VR) after intravitreal injection using Schirmers tear strips was carried out. We assessed its efficiency for proteomics studies by estimating the differential expression of 27 cytokines using multiplexed bead array in diabetic macular oedema and proliferative diabetic retinopathy. To set, validate and assess the efficacy of Schirmer tear strips for collecting VR in patients undergoing intravitreal injections for diabetic macular oedema (DME).Patients and methodsVR samples were collected from 11 eyes of DME patients after intravitreal injections using Schirmer tear strips. Undiluted vitrectomy samples were obtained from six eyes of non-diabetic patients with idiopathic macular hole and seven eyes of diabetic patients with high-risk proliferative diabetic retinopathy (Hr-PDR), which were also subsampled on the Schirmer tear strips. Tear sampling was done in a subset of the DME patients. Total protein concentration between VR and vitrectomy samples was compared. Levels of the set of 27 cytokines in Schirmer tear strips samples were measured. Inter-group comparison for cytokines was done using Mann-Whitney U-test.ResultsSimilar protein concentration in VR samples and vitrectomy samples (P<0.05) was obtained. Tear protein contamination was not detected in VR samples. In comparison with no-DR patients, 25 and 20 of the measured 27 cytokines were significantly elevated (P<0.05) in the Hr-PDR and DME patients, respectively. As compared with no-DR patients, vascular endothelial growth factor was only moderately elevated in DME patients (P>0.05), but significantly elevated in Hr-PDR patients (P<0.05). Interleukin 1 receptor antagonist/interleukin 1b (IL1RA/IL1b) ratio was 13 times higher in DME patients as compared with Hr-PDR group.ConclusionWe demonstrated a simple, safe method of VR sampling. This technique provides a pure, albeit small, vitreous sample for proteomics. IL1RA/IL1b ratio was found to be 13-fold higher in the DME group as compared to the Hr-PDR.

Dexamethasone implant (0.7 mg) in Indian patients with macular edema: Real-life scenario

Context:

Role of Ozurdex in macular edema due to various posterior segment pathologies.

AIM:

The aim of this study is to report outcome of Ozurdex implant in macular edema (ME) secondary to various posterior segment pathologies.

SETTINGS AND DESIGN:

This was a single-center, retrospective, interventional study.

SUBJECTS AND METHODS:

Patients of ME were treated with one or more Ozurdex implants (0.7 mg). Data collection included demographic details, best-corrected visual acuity (BCVA), central foveal thickness (CFT), duration of efficacy, and record of adverse events (if any) within 24 weeks.

STATISTICAL ANALYSIS USED:

Paired sample t-test, Stata data analysis, and statistical software, version 12.1, StataCorp, College Station, TX, USA, were used in the study.

RESULTS:

One hundred and sixteen eyes of 104 patients were studied which had a diagnosis of diabetic ME (n = 46), retinal vein occlusion (n = 40), and uveitis (n = 30). The average age of patients (mean ± standard deviation) was 50.2 ± 21.9 years. Baseline mean ± SD (standard deviation) logMAR BCVA, CFT, and intraocular pressure (IOP) were 0.636 ± 0.4, 527.8 ± 210.1 μm, and 15.3 ± 3.8 mmHg, respectively. The reinjection interval was around 12–18 weeks. Ozurdex proved its efficacy in improving mean logMAR visual acuity and reduction of CFT from baseline till 12 weeks' follow-up period (0.414 ± 0.5 and 301.5 ± 278.5, respectively; P < 0.05), and after 12 weeks' follow-up, it started worsening (0.530 ± 0.9 and 444.8 ± 375.2, respectively; P > 0.05). The most common reported adverse event was significant rise of IOP (>5 mmHg), with a total of 12 cases followed by cataract 9 cases.

CONCLUSION:

Ozurdex implant leads to a significant improvement in BCVA and CFT values till 12 weeks, followed by a gradual decline for all the pathologies studied together. No new safety concerns were observed with the Ozurdex implant. The duration of efficacy was found to be <24 weeks.

Aflibercept in diabetic macular edema refractory to previous bevacizumab: outcomes and predictors of success

PURPOSE

To evaluate functional and anatomical outcomes after aflibercept in patients with diabetic macular edema (DME) with poor response to bevacizumab.

METHODS

We retrospectively reviewed patients with DME recalcitrant to bevacizumab who were switched to aflibercept between January and December 2015. All patients had a minimal follow-up of three months before the conversion and underwent at least three injections of bevacizumab. Functional outcome consisted in best corrected visual acuity (VA). Anatomical outcomes were demonstrated through central macular thickness (CMT) measured by optical coherence tomography.

RESULTS

Forty-nine eyes of 34 subjects were reviewed. Mean VA improved from 0.55 ± 0.32 logMAR to 0.46 ± 0.33 logMAR (p = 0.038). Mean CMT decreased from 473 ± 146 μm to 349 ± 85 μm (p < 0.001). Twelve eyes (24%) demonstrated absence of macular edema after aflibercept. Previous bevacizumab exposure did not correlate with different outcomes. The variation of VA in response to aflibercept was significantly superior in the group with poorer VA before the switch (mean variation of -0.097 ± 0.21 logMAR) when compared to eyes with VA < 0.4 logMAR (mean variation of +0.019 ± 0.090 logMAR; p = 0.036). The same scenario was verified for anatomical outcomes as eyes with poor vision before the switch (≥0.4 logMAR) achieved superior reduction in CMT in response to aflibercept (mean CMT variation of -157 ± 171 μm versus -49.5 ± 39.9 μm; p < 0.01). Pre-switch CMT was a predictor of CMT reduction after switching (B = -0.945; confidence interval 95% -1.1; -0.76; p < 0.001).

CONCLUSIONS

Conversion to aflibercept for persistent DME resulted in functional and anatomical improvements and these outcomes were not influenced by previous bevacizumab exposure. Pre-switch CMT was a predictor of anatomical changes after aflibercept.

Outcomes of Intravitreal Dexamethasone Implant in the Treatment of Recalcitrant Diabetic Macular Edema

Objectives:

To investigate the efficacy and safety of intravitreal dexamethasone (OZURDEX®) implantation in patients with recalcitrant diabetic macular edema.

Materials and Methods:

This is a retrospective non-randomized study of patients who underwent intravitreal dexamethasone implantation for recalcitrant diabetic macular edema. Main outcome measures included changes in best corrected visual acuity (BCVA), central macular thickness (CMT), and incidence of ocular side effects.

Results:

Fifty-seven eyes of thirty-eight patients (20 females, 18 males; mean age 65±7 years) were included in the study. The mean hemoglobin A1c level was 7.9±1.7%. Before entering the study, patients had undergone 5.71±3.40 anti-vascular endothelial growth factor (anti-VEGF) and 3.44±2.46 intravitreal triamcinolone acetonide injections. The mean duration of diabetes and diabetic macular edema was 17.2±6.4 years and 60.2±17.6 months, respectively. At baseline, mean CMT was 506.76±166.74 µm, and the mean BCVA was 0.68±0.38 LogMAR. Mean CMT significantly decreased to 341.36±146.26 µm (p<0.001), 324.41±114.58 µm (p<0.001), and 384.82±151 µm (p<0.001) at 1, 3, and 4 months of follow-up and increased again to 462.29±152.87 µm at 5 months. Sixteen eyes (28%) received second injections after mean of 7.4±2.3 months and mean CMT was again significantly decreased at 7, 8, and 9 months. Significant improvement in mean BCVA (0.54±0.41 LogMAR; p<0.001) occurred only at 1 month after implantation. However, subgroup analysis revealed significant BCVA improvement in the pseudophakic group at 1, 3, and 4 months. Among phakic patients, 50% showed cataract progression and 28% had elevated intraocular pressure increase which was managed medically.

Conclusion:

Intravitreal dexamethasone implantation was effective for the first 4 months in eyes with recalcitrant diabetic macular edema. However, it is hard to displace anti-VEGF agents as first-line therapy due to steroid-related complications.

REAL-LIFE STUDY IN DIABETIC MACULAR EDEMA TREATED WITH DEXAMETHASONE IMPLANT: The Reldex Study

PURPOSE

To evaluate the efficacy and safety of intravitreal implant of dexamethasone (Ozurdex) in diabetic macular edema in real-life practice.

METHODS

In this bicentric retrospective study, the authors reviewed 128 eyes of 89 patients. Main outcome measures included changes in best-corrected visual acuity, central macular thickness, time to retreatment, and incidence of adverse effects. Linear mixed-effects models were used to study changes in best-corrected visual acuity and central macular thickness over the 3-year follow-up.

RESULTS

Best-corrected visual acuity increased by a mean of 3.6 letters at Month 2 (P = 0.005), 4.2 letters at Month 12 (P = 0.006), 5.3 at Month 24 (P = 0.007), and 9.5 letters at Month 36 (P = 0.023). The proportion of eyes achieving at least a 15-letter improvement from baseline was 25.4% at Month 36. Central macular thickness decreased from 451 μm to 289 μm at Month 2 (P < 0.001), 370 μm at Month 12 (P < 0.001), 377 μm at Month 24 (P = 0.004), and 280 μm at Month 36 (P = 0.001). A mean of 3.6 injections were administered over the 3-year follow-up. Ten percent of eyes developed a transient increase in intraocular pressure (IOP ≥ 25 mmHg), and cataract was removed from 47% of phakic eyes.

CONCLUSION

This large case series study showed favorable 3-year outcomes when using Ozurdex to treat diabetic macular edema. Intravitreal Ozurdex provides substantial long-term benefits in the treatment of diabetic macular edema in real-life.

Combined Intravitreal Dexamethasone Implant And Micropulse Yellow Laser For Treatment Of Anti-VEGF Resistant Diabetic Macular Edema

Purpose:

To report the efficacy and safety of combined intravitreal dexamethasone implant and micropulse laser for anti-VEGF resistant diabetic macular edema.

Patients and Methods:

Prospective, non-controlled study that was conducted for twenty eyes with center-involved diabetic macular edema not responding to anti-VEGF therapy. Ozurdex intravitreal implant was injected to all eyes with subsequent micropulse yellow laser one month after the injection. All eyes were followed up after one, three, four, six, nine and twelve months. The primary outcome measure is the change in best corrected visual acuity (BCVA) after one year and secondary outcome measures are central macular thickness (CMT) change and safety of both dexamethasone implant and micropulse laser. Reinjection was done for those eyes with recurrent edema.

Results:

The mean age was 58.8 ±7.94 years. The mean BCVA was 0.6± 0.14, 0.57 ±0.12, 0.51±0.15, 0.59±0.12, 0.6± 0.12 and 0.59±0.14 after one, three, four, six, nine and twelve months in comparison to 0.45± 0.14 as initial BCVA [SS,P<0.05]. The CMT was 302.5±30.01, 330.6±20.24, 357.6±32.15, 285.4±19.95, 292.9±25.07 and 285.2±14.99 after one ,three, four ,six , nine and twelve months µm in comparison to initial CMT of 420.7 ±38.74µm [HS, P<0.01]. Cataract occurred in 6 eyes from 14 phakic eyes (42.8%). Transient ocular hypertension occurred in 6 eyes (30%). Reinjection was done for eight eyes (40%).

Conclusion:

Intravitreal dexamethasone implant and micropulse laser are both effective and safe treatment options for anti-VEGF resistant diabetic macular edema.

Efficacy of the Intravitreal Sustained-Release Dexamethasone Implant for Diabetic Macular Edema Refractory to Anti-Vascular Endothelial Growth Factor Therapy: Meta-Analysis and Clinical Implications

BACKGROUND AND OBJECTIVE

To assess the effect on best-corrected visual acuity (BCVA) and efficacy of the intravitreal sustained-release 0.7 mg dexamethasone implant (Ozurdex; Allergan, Irvine, CA) in patients with recalcitrant diabetic macular edema (DME).

PATIENTS AND METHODS

Meta-analysis utilizing the MOOSE framework and a random effects model. Studies included adults undergoing treatment with Ozurdex for DME. The methodologic quality of each study was assessed using the MINORS and the Cochrane Collaboration Risk of Bias for randomized studies.

RESULTS

A total of 3,859 patients among 15 studies were included in the final analysis. The mean difference in BCVA was a gain of four lines or 20 Early Treatment of Diabetic Retinopathy Study letters with Ozurdex at a mean follow-up period of 6 months.

CONCLUSIONS

Treatment with Ozurdex is associated with significant mean improvement in visual acuity. Clinicians should have a multimodality approach to treating DME and be aware of this treatment option in those who have a suboptimal response to anti-VEGF therapy. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:160-166.].

Use of Corticosteroids in the Treatment of Patients With Diabetic Macular Edema Who Have a Suboptimal Response to Anti-VEGF: Recommendations of an Expert Panel

BACKGROUND AND OBJECTIVE

Guidance on the use of corticosteroids in the treatment of diabetic macular edema (DME) is lacking. This study aimed to develop a clinically recommended treatment paradigm for DME with emphasis on the role of corticosteroids.

PATIENTS AND METHODS

An expert panel of nine retinal specialists in the United States developed consensus recommendations for DME treatment through a modified Delphi process.

RESULTS

The panelists typically use intravitreal injections of vascular endothelial growth factor (VEGF) antagonists as first-line treatment of DME and switch patients with an inadequate response to anti-VEGF therapy (failure of best-corrected visual acuity to improve to 20/40 or better because of edema after three to six monthly injections, or a less-than-50% reduction in excess macular thickness after three to four monthly injections) to intravitreal corticosteroid treatment.

CONCLUSION

Intravitreal corticosteroids have a potentially useful role in the treatment of patients with DME who have an inadequate response to intravitreal anti-VEGF therapy. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:291-301.].

Intravitreal Aflibercept for Patients With Diabetic Macular Edema Refractory to Bevacizumab or Ranibizumab: Analysis of Response to Aflibercept

PURPOSE

To investigate the short-term efficacy and safety of intravitreal aflibercept in a case series of patients with diabetic macular edema (DME) refractory to ranibizumab or bevacizumab.

DESIGN

A retrospective chart review.

METHODS

From September 2013 to March 2016, we identified patients with DME who developed resistance to bevacizumab or ranibizumab. Three monthly intravitreal aflibercept injections were administered in refractory cases. Nonresponse to aflibercept was defined as a paradoxical increase in central foveal thickness (CFT) and gain in best-corrected visual acuity (BCVA) of less than 1 line at 1 month after treatment compared with before aflibercept administration.

RESULTS

Out of a total of 72 eyes in 72 refractory patients, 42 eyes (58.3%) responded to aflibercept injections. The BCVA and CFT were 0.65 ± 0.32 logMAR and 438.5 ± 80.1 μm, respectively, before aflibercept treatment and significantly improved to 0.31 ± 0.17 logMAR (P = 0.0008) and 297.9 ± 19.1 μm (P = 0.0004), respectively, 1 month after 3 aflibercept injections in responders. No differences in baseline characteristics, including age, sex, glycosylated hemoglobin, serum creatinine, total cholesterol, lens status, grades of diabetic retinopathy, and CFT/BCVA before aflibercept management (P > 0.05), were observed between responders and nonresponders. There were 17 vitrectomized eyes in 30 nonresponders (56.7%), a significantly higher rate than among the 42 responders (0%; P = 0.00001).

CONCLUSIONS

Three monthly intravitreal aflibercept injections had benefit in nearly two thirds of cases with DME resistant to bevacizumab or ranibizumab over short-term follow-up. Vitrectomized eyes responded poorly to aflibercept treatment.

PROSPECTIVE RANDOMIZED SUBJECT-MASKED STUDY OF INTRAVITREAL BEVACIZUMAB MONOTHERAPY VERSUS DEXAMETHASONE IMPLANT MONOTHERAPY IN THE TREATMENT OF PERSISTENT DIABETIC MACULAR EDEMA

PURPOSE

To compare intravitreal bevacizumab monotherapy with intravitreal dexamethasone delayed delivery system monotherapy for persistent diabetic macular edema.

METHODS

Single-center, randomized, subject-masked study of eyes with persistent diabetic macular edema, defined as central subfield thickness (CST) >340 μm despite ≥3 anti-vascular endothelial growth factors injections within 5 months. The intravitreal bevacizumab monotherapy (n = 23 eyes) and delayed delivery system monotherapy (n = 27 eyes) groups received treatments q1month and q3months, respectively.

RESULTS

Baseline best-corrected visual acuity and CST were similar in the two groups. At Month 7, the mean final best-corrected visual acuity (mean ± SD) was 65 ± 16 letters (mean Snellen visual acuity 20/50) and 64 ± 11 letters (20/50) (P = 0.619), the mean change in best-corrected visual acuity was +5.6 ± 6.1 and +5.8 ± 7.6 letters (P = 0.785), the mean final CST was 471 ± 157 and 336 ± 89 μm (P = 0.001), and the mean change in CST was -13 ± 105 and -122 ± 120 μm (P = 0.005) in the intravitreal bevacizumab monotherapy and delayed delivery system monotherapy groups, respectively. The number of injections was 7.0 ± 0.2 and 2.7 ± 0.5 (P < 0.001) in the 2 groups.

CONCLUSION

The two groups had similar best-corrected visual acuity gains. The delayed delivery system monotherapy group achieved a significantly greater reduction of CST compared with the intravitreal bevacizumab monotherapy group, with a q3month interval of treatment, and had no recurrent edema at any visit.

A multicenter, 12-month randomized study comparing dexamethasone intravitreal implant with ranibizumab in patients with diabetic macular edema

PURPOSE

To evaluate whether treatment with dexamethasone intravitreal implant (DEX implant) 0.7 mg every 5 months provides a similar average change in best-corrected visual acuity (BCVA) from baseline as ranibizumab 0.5 mg administered as per its European Summary of Product Characteristics in patients with diabetic macular edema (DME).

METHODS

This was a multicenter, open-label, 12-month, randomized, parallel-group, noninferiority study in patients with DME (one eye/patient). The primary efficacy measure was BCVA using the Early Treatment Diabetic Retinopathy Study (ETDRS) method. Secondary efficacy measures included area of leakage on fluorescein angiography and central retinal thickness (CRT) on optical coherence tomography.

RESULTS

Baseline patient characteristics were similar in the two treatment groups (DEX implant, n = 181; ranibizumab, n = 182); mean DME duration was ∼33 months. The mean average BCVA change from baseline over 12 months was 4.34 letters with DEX implant and 7.60 letters with ranibizumab. The lower limit of the 95 % confidence interval of the between-group difference was -4.74 letters, and therefore, DEX was demonstrated to be noninferior to ranibizumab based on the prespecified noninferiority margin of 5 letters. At monthly follow-up visits, the percentage of patients with ≥15-letter BCVA gain from baseline ranged from 7.2 to 17.7 % with DEX implant and 4.4 to 26.9 % with ranibizumab. Both DEX implant and ranibizumab effectively reduced CRT and reduced the area of fluorescein leakage. Between-group differences in change from baseline CRT favored DEX implant at 1, 2, 6, and 7 months (p ≤ 0.007) and ranibizumab at 4, 5, 9, and 10 months (p < 0.001); the decrease in fluorescein leakage area was greater with DEX implant than ranibizumab at month 12 (p < 0.001). Ocular adverse events in the study eye were more frequent in the DEX implant group because of the occurrence of intraocular pressure (IOP) increases and cataract. IOP increases were transient and generally managed with topical medication.

CONCLUSIONS

Both DEX implant and ranibizumab were well tolerated and improved BCVA and anatomic outcomes in patients with DME. DEX implant met the a priori criterion for noninferiority to ranibizumab in average change from baseline BCVA over 12 months. Noninferiority was achieved with an average of 2.85 DEX implant injections and 8.70 ranibizumab injections per patient.

Contralateral eye-to-eye comparison of intravitreal ranibizumab and a sustained-release dexamethasone intravitreal implant in recalcitrant diabetic macular edema

Objective

To compare the effects of intravitreal ranibizumab (RZB) or dexamethasone (DEX) intravitreal implant in cases of recalcitrant diabetic macular edema (DME).

Methods

Retrospective, interventional study examining patients with symmetric bilateral, center-involved DME recalcitrant to treatment with RZB, who received DEX in one eye while the contralateral eye continued to receive RZB every 4–5 weeks for a study period of 3 months.

Results

Eleven patients (22 eyes) were included: mean logarithm of the minimal angle of resolution (logMAR) visual acuity (VA) for the DEX arm improved from 0.415 (standard deviation [SD] ±0.16) to 0.261 (SD ±0.18) at final evaluation, and mean central macular thickness (CMT) improved from 461 µm (SD ±156) to 356 µm (SD ±110; net decrease: 105 µm, P=0.01). Mean logMAR VA for the RZB arm improved from 0.394 (SD ±0.31) to 0.269 (SD ±0.19) at final evaluation. Mean CMT improved from 421 µm (SD ±147) to 373 µm (SD ±129; net decrease: 48 µm, P=0.26).

Conclusion

A subset of recalcitrant DME patients demonstrated significant CMT reduction and VA improvement after a single DEX injection.

Diabetic macular oedema: pathophysiology, management challenges and treatment resistance

Diabetic macular oedema (DMO) is the leading cause of vision loss in patients living with diabetes. DMO results from hyperglycaemia-induced activation of pathways that lead to oxidative stress and release of cytokines, impairing the inner and outer blood-retinal barriers. Improved understanding of the pathophysiological mechanisms leading to DMO have led to the development of effective therapies, including vitreoretinal surgery, laser photocoagulation, intravitreal anti-vascular endothelial growth factor drugs and corticosteroids. Advances in imaging, including fluorescein angiography and optical coherence tomography, have also enhanced diagnosis and management of the condition. Despite these advances, there remain patients who do not respond completely to therapy, reflecting the complex pathophysiology of DMO. These patients may be considered treatment-resistant. In this review, we summarise the pathophysiology of DMO, as well as the available treatments and their mechanism of action. Additionally, we focus on treatment-resistant disease and review the literature on potential options for managing this complication of diabetes.

Long-lasting corneal endothelial graft rejection successfully reversed after dexamethasone intravitreal implant

Graft rejection is the most significant complication corneal transplantation and the leading indication for overall corneal transplantation. Corticosteroid therapy represents the mainstay of graft rejection treatment; however, the optimal route of administration of corticosteroid remains uncertain. We report herein for the first time the multimodal imaging of a case of long-lasting corneal endothelial graft rejection successfully reversed 3 months after dexamethasone intravitreal implant. A 29-year-old Asian female presented with a long-lasting corneal endothelial graft rejection in her left phakic eye. She underwent penetrating keratoplasty for advanced keratoconus 24 months before presentation. Hourly dexamethasone eyedrops, daily intravenous methylprednisolone, and one parabulbar injection of methylprednisolone acetate were administered during the 5 days of hospitalization. However, the clinical picture remained approximately unchanged despite therapy. By mutual agreement, we opted for the off-label injection of dexamethasone 0.7 mg intravitreal implant in order to provide therapeutic concentrations of steroid for a period of ~6 months. No other concomitant therapies were prescribed to the patient. Visual acuity measurement, slit lamp biomicroscopy, anterior segment photography, confocal microscopy, anterior segment optical coherence tomography, laser cell flare meter, intraocular pressure measurement, and ophthalmoscopy were performed monthly for the first postoperative 6 months. Three months after injection, both clinical and subclinical signs of rejection disappeared with a full recovery of visual acuity to 20/30 as before the episode. Currently, at the 12-month follow-up visit, the clinical picture remains stable without any sign of rejection, recurrence, or graft failure. Dexamethasone intravitreal implant seems to be a new potential effective treatment for corneal graft rejection, particularly in case of poor compliance or lack of response to conventional treatment. In addition, it could be especially useful in diabetic patients unable to receive systemic steroids.

Role of implants in the treatment of diabetic macular edema: focus on the dexamethasone intravitreal implant

Diabetic macular edema (DME) is the leading cause of sight-threatening complication in diabetic patients, and several treatment modalities have been developed and evaluated to treat this pathology. Intravitreal agents, such as anti-vascular endothelial growth factors (anti-VEGF) or corticosteroids, have become more popular in recent years and are widely used for treating DME. Sustained release drugs appear to be mentioned more often nowadays for extending the period of intravitreal activity, and corticosteroids play a key role in inhibiting the inflammatory process in DME. A potent corticosteroid, dexamethasone (Ozurdex(®)), in the form of an intravitreal implant, has been approved for various ocular etiologies among which DME is also one. This review evaluates the role of implants in the treatment of DME, mainly focusing on the dexamethasone intravitreal implant.