Dexamethasone intravitreal implant for treatment of patients with persistent diabetic macular edema

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

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

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.

Optical Coherence Tomography Reflectivity in Foveal Cysts: A Novel Biomarker for Early-Response Prediction of Diabetic Macular Edema Treated with Dexamethasone

This study investigated spectral-domain optical coherence tomography (OCT) biomarkers to predict short-term anatomical improvement for diabetic macular edema (DME) after dexamethasone (DEX) injection in intravitreal anti-vascular endothelial growth factor (anti-VEGF) non-responders. This retrospective comparative study included 31 eyes of 31 patients with DME unresponsive to anti-VEGF, divided into better and lesser responder groups. OCT prior to DEX injection was used to evaluate the morphological features including optical density (ODN) and optical density ratio (ODR) of the outer nuclear layer (ONL) cysts. Correlations between baseline OCT parameters and mean central macular thickness (CMT) changes at 1 month were analyzed. There were no between-group differences in age, sex, number of previous anti-VEGF injections, duration of diabetes, or HbA1c level. However, ODN and ODR values in ONL cysts were lower in the better responder group (p = 0.020 and p < 0.001, respectively). ODN and ODR showed negative correlations with CMT changes (R = −0.546, p = 0.002 and R = −0.436, p = 0.014, respectively). Higher OCT reflectivity in the foveal cystoid space was associated with a lesser decrease in CMT after DEX injection in anti-VEGF non-responders, suggesting the usefulness of this parameter in predicting short-term CMT responses after DEX injection.

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.

CHANGES IN SUBFOVEAL CHOROIDAL THICKNESS AFTER INTRAVITREAL DEXAMETHASONE IMPLANT THERAPY FOR DIABETIC MACULAR EDEMA

PURPOSE

To investigate changes in subfoveal choroidal thickness (SFCT) and their relationship with best-corrected visual acuity and optical coherence tomography parameters after intravitreal dexamethasone implant injection for diabetic macular edema.

METHODS

Eighty-one eyes treated with dexamethasone implant injection for diabetic macular edema were evaluated for best-corrected visual acuity, central macular thickness, SFCT, and optical coherence tomography parameters at baseline and Weeks 7 and 14.

RESULTS

The mean baseline SFCT significantly decreased at Weeks 7 (P < 0.001) and 14 (P < 0.001). At Week 7, each 1-µm reduction in central macular thickness and five Early Treatment Diabetic Retinopathy Study letters (-0.1 logarithm of the minimal angle of resolution) improvement were associated with SFCT reductions of 0.09 (P = 0.002) and 3.91 (P = 0.044) µm, respectively. At Week 14, each 1-µm reduction in central macular thickness was associated with a 0.14-µm reduction in SFCT (P < 0.001). Eyes with good functional and anatomical responses exhibited significantly greater SFCT reductions. Subretinal fluid resulted in greater SFCT changes (P = 0.039) and better best-corrected visual acuity (P = 0.033) at Week 7. A continuous ellipsoid zone/interdigitation zone layer was associated with a smaller mean SFCT at Week 7 (P = 0.002) and better best-corrected visual acuity at Weeks 7 and 14 (both, P < 0.001).

CONCLUSION

Changes in SFCT after dexamethasone implant injection therapy for diabetic macular edema may predict anatomical and functional outcomes and correlate with optical coherence tomography features that are known as predictors of treatment response.

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.

DEXAMETHASONE IMPLANT FOR DIABETIC MACULAR EDEMA IN NAIVE COMPARED WITH REFRACTORY EYES: The International Retina Group Real-Life 24-Month Multicenter Study. The IRGREL-DEX Study

PURPOSE

To investigate efficacy and safety of repeated dexamethasone (DEX) implants over 24 months, in diabetic macular edema (DME) eyes that were treatment naive compared with eyes refractory to anti-vascular endothelial growth factor treatment, in a real-life environment.

METHODS

This multicenter international retrospective study assessed best-corrected visual acuity and central subfield thickness (CST) of naive and refractory eyes to anti-vascular endothelial growth factor injections treated with dexamethasone implants. Safety data (intraocular pressure rise and cataract surgery) were recorded.

RESULTS

A total of 130 eyes from 125 patients were included. Baseline best-corrected visual acuity and CST were similar for naive (n = 71) and refractory eyes (n = 59). Both groups improved significantly in vision after 24 months (P < 0.001). However, naive eyes gained statistically significantly more vision than refractory eyes (+11.3 ± 10.0 vs. 7.3 ± 2.7 letters, P = 0.01) and were more likely to gain ≥10 letters (OR 3.31, 95% CI 1.19-9.24, P = 0.02). At 6, 12, and 24 months, CST was significantly decreased compared with baseline in both naive and refractory eyes; however, CST was higher in refractory eyes than in naive eyes (CST 279 ± 61 vs. 313 ± 125 μm, P = 0.10).

CONCLUSION

Over a follow-up of 24 months, vision improved in diabetic macular edema eyes after treatment with dexamethasone implants, both in eyes that were treatment naive and eyes refractory to anti-vascular endothelial growth factor treatment; however, improvement was greater in naive eyes.

Disorganization of retinal inner layers as a biomarker in patients with diabetic macular oedema treated with dexamethasone implant

PURPOSE

To investigate disorganization of retinal inner layers (DRIL) as a biomarker in eyes with diabetic macular oedema (DME) treated by intravitreal dexamethasone (DEX) implant.

METHODS

Multicentre, retrospective study including eyes with DME treated with DEX implant and follow-up of 12 months after the first injection. OCT scans were evaluated for the presence of DRIL and other structural features. Best corrected visual acuity (BCVA) and central subfield thickness (CST) were recorded at baseline and at 2, 4, 6 and 12 months after treatment. Correlation between DRIL at baseline and outcomes after DEX treatment and the change in DRIL were analysed.

RESULTS

A total of 177 eyes (177 patients; naïve, n = 131; refractory, n = 46) were included. Patients without DRIL at baseline gained significantly more vision and enjoyed greater reduction in CST over 12 months (both p = 0.03). DRIL at the boundary between the ganglion cell-inner plexiform complex and inner nuclear layer improved in 48/64 eyes (75%, p < 0.001), while DRIL between the inner nuclear layer and outer plexiform layer improved in 27/77 eyes (35%, p = 0.004).

CONCLUSIONS

This is the first study to show that DEX implant has the potential to ameliorate DRIL. Patients without DRIL at baseline have a favourable outcome. DRIL may serve a robust biomarker in DME treated by DEX implant.

The Effects of Epiretinal Membranes on the Treatment Outcomes of Dexamethasone Implants in Diabetic Macular Edema: A Real-Life Study

Purpose: To evaluate the effects of a coexisting epiretinal membrane (ERM) on the treatment outcomes of a dexamethasone implant (DI) in diabetic macular edema (DME) patients. Methods: One hundred five eyes of 78 DME patients (44 F, 34 M; mean age: 65.7) treated with minimum 2 DIs were enrolled into this retrospective study. The study population was divided into the ERM (+) study group and the ERM (-) control group. The best corrected visual acuity (BCVA), intraocular pressure, and central macular thicknesses (CMTs) were evaluated at baseline and months 1, 2, and 3 after each DI treatment. Results: Both groups were comparable in baseline BCVA, CMT, HbA1c levels, and age. In the study group (n: 49), BCVA changed following the first DI from 0.83 to 0.76 and from 0.97 to 0.80 following the second DI. CMT decreased after the first DI from 465 to 377 μ (P < 0.001) and from 477 to 356 μ (P < 0.001) after the second DI. In the control group (n: 56), BCVA changed following the first DI from 0.81 to 0.77 and from 0.86 to 0.83 following the second DI. After the first DI, CMT decreased from 483 to 280 μ (P < 0.001) and from 468 to 301 μ (P < 0.001) after the second DI. The inter-group comparison revealed no significant difference in visual or anatomical gain (P = 0.46, P = 0.05, respectively). Conclusion: The presence of an epiretinal membrane did not change the treatment response to DI therapy.

The effects of intravitreal triamcinolone acetonide in diabetic macular edema refractory to anti-VEGF treatment

PURPOSE

To investigate the efficacy and safety of primary intravitreal triamcinolone acetonide (IVTA) in eyes affected by diabetic macular edema (DME) refractory to anti-vascular endothelial growth factor (VEGF) therapy.

STUDY DESIGN

Retrospective observational study METHODS: The medical records of patients who attended our clinic from March 2013 to September 2018 with refractory macular were reviewed. We included the patients who were injected at least one IVTA and completed 6 months of observation. Best-corrected Snellen visual acuity (VA), central macular thickness (CMT), intraocular pressure (IOP), and adverse events (AEs) were examined at baseline and at 1 month, 2 months, 3 months, and 6 months.

RESULTS

Sixty-four eyes of 54 subjects were included. The mean VA was improved significantly at all time points compared to pre-treatment (P < 0.0001), with the greatest mean improvement at 1 month (0.3 logMAR). The reduction in mean CMT was also significant at all follow-up examinations compared to baseline (P < 0.0001), with the greatest decrease at 1 month (113.68 ± 53.78 μm). A poorer VA before injection was a factor that influenced visual gain 1 month post treatment (0.247 logMAR units/unit increase in baseline VA, P = 0.006). The most common AE associated with IVTA treatment was elevated IOP (11 eyes), observed significantly more often after IVTA injections containing a preservative (25.8%) than after those that were preservative-free (9.1%) (P = 0.033).

CONCLUSION

IVTA injection can be an alternative steroid treatment for DME refractory to anti-VEGF therapy.

Association between Hyperreflective Foci on Spectral-Domain Optical Coherence Tomography and Early Recurrence of Diabetic Macular Edema after Intravitreal Dexamethasone Implantation

Purpose

To investigate the associations between hyperreflective foci (HRF) on spectral-domain optical coherence tomography (SD-OCT) and early recurrence of macular edema after intravitreal dexamethasone (DEX) implantation in eyes with refractory diabetic macular edema (DME) to bevacizumab.

Methods

Medical records of patients with refractory DME to bevacizumab, who underwent intravitreal DEX implantation and 12-month follow-up, were reviewed. Eyes in which central subfield thickness (CST) increased over 50 μm at 3 months compared with the first month after intravitreal DEX implantation were categorized into the early recurrence group, and the others were categorized into the late recurrence group. Best-corrected visual acuity (BCVA), CST, and number of HRF on SD-OCT were analyzed.

Results

Twenty-nine eyes of 26 patients (16 eyes in the early recurrence group and 13 eyes in the late recurrence group) were included in this study. The numbers of HRF in entire retina, inner retina, and outer retina at baseline in the early recurrence group (11.38 ± 3.07 in entire retina, 5.44 ± 1.50 in inner retina, 5.94 ± 2.74 in outer retina) were significantly greater than those in the late recurrence group (7.54 ± 3.60 in entire retina, p=0.006; 4.08 ± 1.70 in inner retina, p=0.034; 3.46 ± 2.30 in outer retina, p=0.013). Multivariate logistic regression analysis showed that a higher number of HRF increased the risk of early recurrence after intravitreal DEX implantation (odds ratio in entire retina: 1.518, p=0.012; odds ratio in inner retina: 2.058, p=0.027; odds ratio in outer retina: 1.610, p=0.029).

Conclusions

Higher baseline numbers of HRF on SD-OCT may be a predictive indicator of early recurrence of macular edema after intravitreal DEX implantation for DME.

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.

A Collaborative Retrospective Study on the Efficacy and Safety of Intravitreal Dexamethasone Implant (Ozurdex) in Patients with Diabetic Macular Edema: The European DME Registry Study

PURPOSE

To evaluate the efficacy, effect profile, and safety of dexamethasone implant on diabetic macular edema (DME) in a real-life setting, further comparing results by DME duration, previous treatment status, and diabetic control.

DESIGN

A multicenter, retrospective cohort of 340 DME eyes of 287 patients from 25 clinical sites from 8 countries.

METHODS

Data were analyzed in 2 perspectives: per injection, in which all measurements were grouped and baseline was defined as the day of injection, and thus the pharmacodynamics of single injections could be assessed; and injection series, defined as 2 or more injections with 3 to 6 months between injections analyzing the outcome 3 to 6 months after the last injection.

MAIN OUTCOME MEASURES

Primary outcome was improvement of 15 or more letters in best-corrected visual acuity (BCVA) from baseline. Secondary outcomes included improvement of 10 letters or more in BCVA, change in central macular thickness (CMT), and time to maximum improvement and safety.

RESULTS

Overall, 762 injections were administered to 340 eyes of 287 patients. Injection series analysis included 171 series in 171 eyes of 150 patients, for a total of 444 injections, with a mean follow-up of 1.7±0.8 years. Of the 762 injections analyzed per injection, 22.7% achieved a 15-letter or more improvement, and 37.8% achieved a 10-letter or more improvement. Mean time to peak improvement was 81.9±39.7 days. Mean maximum change in CMT was -174±171 μm. Overall, 7.6% lost 15 or more letters. More eyes with early DME gained 10 or more letters and fewer eyes lost 10 or more letters compared with eyes with late DME (47.4% vs. 33.9% [P = 0.001] and 8.2% vs. 13.5% [P = 0.029], respectively). Patients with controlled diabetes showed greater CMT reduction (P = 0.0002). A higher percentage of treatment-naive patients gained 10 or 15 letter or more in BCVA (P = 0.001 and P = 0.006, respectively). Intraocular pressure elevation of more than 25 mmHg was found following 7.9% of injections; no endophthalmitis was reported.

CONCLUSIONS

Dexamethasone implant is an effective and safe treatment for DME. Peak improvement was achieved 3 months after injection and dissipated thereafter. Clinicians and providers may consider shortening treatment intervals.

Efficacy of vitrectomy combined with an intraoperative dexamethasone implant in refractory diabetic macular edema

AIMS

To evaluate the safety and efficacy of vitrectomy combined with an intraoperative dexamethasone (Ozurdex^®) implant in refractory diabetic macular edema (DME).

METHODS

Patients who were diagnosed at our institution as having DME refractory to more than 6 months of non-surgical treatment and underwent intravitreal dexamethasone implantation combined with vitrectomy. All patients were followed up for more than 12 months. Best-corrected visual acuity (BCVA, logMAR), central macular thickness (CMT), and intraocular pressure at the initial visit and 1, 3, 4, 6, and 12 months after treatment were recorded.

RESULTS

Twenty-two eyes (22 patients) were included in this study. The mean preoperative BCVA was 0.68 and the mean CMT was 470.80 µm. The total number of the previous injections was 5.1 ± 1.6. The mean BCVA was significantly improved at all visits, and the mean CMT was also significantly reduced (p < 0.05). Sixteen eyes (73%) did not need additional implantations during follow-up.

CONCLUSIONS

Vitrectomy combined with an intraoperative dexamethasone (Ozurdex) implant was an effective and safe treatment option in patients with refractory DME.

Early versus late switch: How long should we extend the anti-vascular endothelial growth factor therapy in unresponsive diabetic macular edema patients?

PURPOSE

To compare the results of early versus late switch to the dexamethasone intravitreal implant Ozurdex^® in patients with diabetic macular edema who had a poor response to vascular endothelial growth factor inhibitors.

METHODS

Retrospective and single-center study conducted, in a real setting, on consecutive diabetic macular edema patients who were switch to an intravitreal dexamethasone implant after a poor response to anti-vascular endothelial growth factor treatment. Study sample was divided into two groups: (1) early-switch group, included those eyes who received three anti-vascular endothelial growth factor injections before switch and (2) late-switch group, included those eyes that received six or more anti-vascular endothelial growth factor injections before switch. The primary end-point was the difference in mean change in best-corrected visual acuity and in central subfoveal thickness.

RESULTS

A total of 69 (31 early-switch group and 38 late-switch group) eyes were included. In the early-switch group, median (25-75 quartile range) best-corrected visual acuity significantly increase from 0.2 (0.2-0.5) at baseline to 0.4 (0.3 -0.7) at month 24 (p = 0.0043). Whereas, in the late-switch group, best-corrected visual acuity did not increase (p = 0.8602). Central subfoveal thickness was significantly reduced in both early- and late-switch groups, p = 0.0002 and 0.0038, respectively. The proportion of eyes obtaining a central subfoveal thickness reduction ⩾ 10% was significantly greater in the early-switch group than in the late-switch group (71.0% vs 47.4%, respectively, p = 0.0498). Three (9.7%) and 10 (26.3%) eyes have developed ocular hypertension during the study in the early- and late-switch groups, respectively, p = 0.0816.

CONCLUSION

Early switch to Ozurdex in patients who did not adequately respond to anti-vascular endothelial growth factor therapy provided better functional and anatomical outcomes.

Effectiveness and Safety of Intravitreal Dexamethasone Implant (Ozurdex) in Patients with Diabetic Macular Edema: A Real-World Experience

INTRODUCTION

There are few real-life studies on the intravitreal 0.7-mg dexamethasone implant for the treatment of diabetic macular edema (DME) conducted in Latin America. We aimed to assess the effectiveness and safety of this implant in clinical practice.

METHODS

Twenty-seven centers from Brazil and one from Argentina provided information on patients with DME treated with Ozurdex. The efficacy outcome variables were best-corrected visual acuity (BCVA) in Snellen and central retinal thickness (CRT). Safety was assessed by the elevation in intraocular pressure (IOP), occurrence of cataracts, and adverse events.

RESULTS

A total of 329 eyes (both treated cases and naïve eyes) from 282 patients underwent treatment. The time since diagnosis of DME ranged from 1 to 156 months. The median BCVA was 0.7 logMAR/50 letters at baseline and 0.3 logMAR/70 letters after treatment (both p < 0.001). Median CRT values decreased from 425 µm at baseline to 270 µm after treatment (p < 0.001). Increases in IOP of at least 10 mm Hg were observed in 7.4% of eyes, and 4% of eyes had cataract evolution. No cases of endophthalmitis were reported.

CONCLUSION

These real-life results suggest that the intravitreal dexamethasone implant is effective and safe for eyes with DME.

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.

Shall we stay, or shall we switch? Continued anti-VEGF therapy versus early switch to dexamethasone implant in refractory diabetic macular edema

AIMS

To compare functional and anatomical outcomes of continued anti-vascular endothelial growth factor (VEGF) therapy versus dexamethasone (DEX) implant in eyes with refractory diabetic macular edema (DME) after three initial anti-VEGF injections in a real-world setting.

METHODS

To be included in this retrospective multicenter, case-control study, eyes were required: (1) to present with early refractory DME, as defined by visual acuity (VA) gain ≤ 5 letters or reduction in central subfield thickness (CST) ≤ 20%, after a loading phase of anti-VEGF therapy (three monthly injections) and (2) to treat further with (a) anti-VEGF therapy or (b) DEX implant. Main outcome measures were change in visual acuity (VA) and central subfield thickness (CST) at 12 months. Due to imbalanced baseline characteristics, a matched anti-VEGF group was formed by only keeping eyes with similar baseline characteristics as those in the DEX group.

RESULTS

A total of 110 eyes from 105 patients were included (anti-VEGF group: 72 eyes, DEX group: 38 eyes). Mean change in VA at 12 months was - 0.4 ± 10.8 letters (anti-VEGF group), and + 6.1 ± 10.6 letters (DEX group) (P = 0.004). Over the same period, mean change in CST was + 18.3 ± 145.9 µm (anti-VEGF group) and - 92.8 ± 173.6 µm (DEX group) (P < 0.001). Eyes in the DEX group were more likely to gain ≥ 10 letters (OR 3.71, 95% CI 1.19-11.61, P = 0.024) at month 12.

CONCLUSIONS

In a real-world setting, eyes with DME considered refractory to anti-VEGF therapy after three monthly injections which were switched to DEX implant and had better visual and anatomical outcomes at 12 months than those that continued treatment with anti-VEGF therapy.

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.

Polyester elastomers for soft tissue engineering

Polyester elastomers are soft, biodegradable and biocompatible and are commonly used in various biomedical applications, especially in tissue engineering. These synthetic polyesters can be easily fabricated using various techniques such as solvent casting, particle leaching, molding, electrospinning, 3-dimensional printing, photolithography, microablation etc. A large proportion of tissue engineering research efforts have focused on the use of allografts, decellularized animal scaffolds or other biological materials as scaffolds, but they face the major concern of triggering immunological responses from the host, on top of other issues. This review paper will introduce the recent developments in elastomeric polyesters, their synthesis and fabrication techniques, as well as their application in the biomedical field, focusing primarily on tissue engineering in ophthalmology, cardiac and vascular systems. Some of the commercial and near-commercial polyesters used in these tissue engineering fields will also be described.

Evaluation of the effect of combined intravitreal ranibizumab injection and sub-tenon steroid injection in the treatment of resistant diabetic macular edema

PURPOSE

To compare sub-tenon steroid plus anti-VEGF injection with anti-VEGF injection solely in the treatment of resistant diabetic macular edema (DME).

METHOD

Patients who exhibited insufficient anatomic [over 350 μm central macular thickness (CMT)] and less than 3 lines of visual gain at least six anti-VEGF injections, were randomly divided into two groups. In group I, the anti-VEGF injection was performed 10 days after the sub-tenon steroid injection [Triamcinolone acetonide (Sinakort-A^®)]. And anti-VEGF was performed when needed during the follow-up period. In group II, treatment was continued with anti-VEGF only. All patients' visual acuity and CMT were followed up for 6 months.

RESULTS

The baseline BCVA in group I and group II was 0.51 ± 0.667 logMAR and 0.47 ± 0.60 logMAR, respectively (p = 0.52). In group I and II, at the end of 6-month follow-up, BCVA improved to 0.38 ± 0.60 logMAR (p < 0.001) and 0.43 ± 0.60 logMAR (p = 0.20), respectively. The baseline CMT in group I and group II was 494 ± 118.32 and 438.20 ± 90.99 μm, respectively (p = 0.029). In group I and II, at the end of 6 months, CMT decreased to 302.57 ± 69.89 μm (p < 0.001) and 439.20 ± 107.6 μm (p = 0.96), respectively.

CONCLUSION

Adding steroid to routine anti-VEGF treatment is an effective way of treatment method for resistant DME.

Treatment outcomes and predicting factors for diabetic macular edema treated with ranibizumab - One-year real-life results in Taiwan

PURPOSE

To report the one-year outcomes of diabetic macular edema (DME) treated with ranibizumab under a real-life setting in Taiwan, and to identify the prognostic factors.

METHODS

Between July 2013 and January 2015, 119 eyes receiving intravitreal ranibizumab for DME were retrospectively recruited. Best-corrected visual acuity (BCVA) and central foveal thickness (CFT) measured with optical coherence tomography were collected at baseline and at Month 3, 6, and 12. Linear regression was used to identify the predicting factors for changes in BCVA and CFT at Month 12.

RESULTS

The average number of ranibizumab given within one year was 4.36 ± 1.87. The BCVA (logMAR) improved from 0.74 ± 0.30 at baseline to 0.64 ± 0.37 at Month 12 (p = 0.002). A better improvement in BCVA at Month 3 was significantly correlated with a better visual improvement at Month 12 (p < 0.001). The existence of subretinal fluid at baseline (p = 0.02) and a greater reduction in CFT at Month 3 (p < 0.001) were both correlated with a greater reduction in CFT at Month 12. Previous subtenon injection of triamcinolone acetonide was associated with fewer additional IVR after Month 3 (odds ratio = 0.35, 95% CI = 0.14-0.89).

CONCLUSION

Compared with existing prospective studies, the one-year real-life data in Taiwan showed fewer ranibizumab injections for DME and a less prominent yet still significant visual improvement. Both visual and anatomical improvements at Month 3 were correlated with the level of improvements at Month 12. Previous subtenon steroid injection might reduce the need of additional ranibizumab injections.

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.

OCT Biomarkers as Functional Outcome Predictors in Diabetic Macular Edema Treated with Dexamethasone Implant

PURPOSE

Identification and characterization of patients with diabetic macular edema (DME) are important for individualizing treatment and optimizing outcome. We investigated OCT biomarkers for DME treated by intravitreal dexamethasone (DEX) implant.

DESIGN

Multicenter, retrospective, observational cohort study.

PARTICIPANTS

A total of 299 eyes from 284 patients treated with DEX implant for DME (naïve, n = 209; refractory, n = 90). Baseline best-corrected visual acuity (BCVA) was between 0.3 and 1.0 on a logarithm of minimum angle of resolution visual chart.

METHODS

The OCT scans previous to DEX implants were evaluated for submacular fluid, size and location of cystoid changes, inner segment-outer segment (IS-OS) continuity, quantity and location of hyperreflective foci (HRF), vitreomacular interface abnormalities, and epiretinal membrane. The BCVA and central macular thickness were recorded at baseline and at 1, 2, and 4 months after treatment with DEX implants. Correlations between OCT measures and visual outcome were analyzed using the generalized estimating equations procedure.

MAIN OUTCOME MEASURES

The correlation between spectral-domain (SD) OCT measures at baseline and BCVA response (mean change from baseline; categorized improvement [<5, 5-9, or ≥10; Early Treatment Diabetic Retinopathy Study letters] in BCVA) after treatment with a DEX implant.

RESULTS

The presence of subretinal fluid (odds ratio [OR], 1.98; 95% confidence interval [CI], 1.23-3.20; P = 0.01), absence of HRF (OR, 3.66; 95% CI, 1.40-9.62; P = 0.01), and integrity of the IS-OS layer (OR, 2.09; 95% CI, 1.30-3.37; P = 0.003) were all predictive of better visual outcome after treatment with DEX implants. Although eyes with naïve DME gained more vision than refractory eyes (P < 0.001), the predictive value of OCT findings did not differ according to this classification.

CONCLUSIONS

Spectral-domain OCT is useful in identifying various imaging findings in DME. Among eyes with DME, those with submacular fluid, no HRF, and a continuous IS-OS layer responded better to DEX implants than those without these features. These findings call for further study of combinations of OCT and metabolic biomarkers.

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.].

New Drugs and New Posterior Delivery Methods in CME

PURPOSE

To discuss the characteristics, indications and adverse events (AEs) of sustained-release corticosteroid devices for the treatment of cystoid macular edema (CME).

RECENT FINDINGS

Ozurdex® is approved for the treatment of diabetic macular edema (DME), retinal vein occlusion related-CME and noninfectious posterior uveitis (NIPU). It releases dexamethasone over a maximum period of 6 months making repeated intravitreal injections necessary for recurrent CME. Iluvien® releases fluocinolone for up to 36 months and is effective for the treatment of chronic DME. Retisert® (Bausch & Lomb, Rochester, NY) also releases fluocinolone, and is approved for chronic NIPU. Both Iluvien® and Retisert® are non-biodegradable devices and are highly associated with cataract and glaucoma.

SUMMARY

Long-acting intraocular corticosteroid formulations offer a more predictable drug-release profile and reduced dosing frequency in comparison to conventional formulations of the same compounds but the risk-benefit ratio must be taken into consideration previous to the implantation of those devices.

Efficacy and Safety of Intravitreal Dexamethasone Implants for Treatment of Refractory Diabetic Macular Edema

Purpose

To evaluate the safety and efficacy of intravitreal dexamethasone (IVD) implants in eyes with diabetic macular edema that did not respond to previous treatment.

Methods

We included 46 eyes of 46 patients in this retrospective study. Each month, we recorded patient visual acuity with logarithm of the minimum angle of resolution using the Early Treatment Diabetic Retinopathy Study chart, central macular thickness measurements with optical coherence tomography, intraocular pressure (IOP), and posttreatment complication occurrence.

Results

The mean follow-up time was 8.95 ± 1.33 months (range, 6 to 12). Best-corrected visual acuity improved significantly in the first 4 months after IVD, but no statistically significant change was observed over the following 2 months. Although a statistically significant decrease in central macular thickness was observed in the first 3 months, the change was not statistically significant in the following 3 months. There was a statistically significant increase in IOP in the first 2 months, but no statistically significant change was observed in the following months. IOP was controlled with medication in all patients with elevated IOP. Of the 26 phakic patients, two had cataracts requiring surgery.

Conclusions

Cases of refractory diabetic macular edema that did not respond to previous treatment, such as anti-vascular endothelial growth factor injections and laser photocoagulation, exhibited improvements in visual acuity and decreases in retinal thickness after IVD implantation. Both functional and anatomical effects were observed in the first 3 months after injection. Repeat injections and frequent examination might be required for continued improvement. Side effects, such as cataracts and elevation of IOP, may require medical or surgical treatment.

Twelve-Month Follow-Up of Dexamethasone Implants for Macular Edema from Various Diseases in Vitrectomized and Nonvitrectomized Eyes

Purpose. To evaluate the best-corrected visual acuity (BCVA), central retinal thickness (CRT), and the number of dexamethasone implants needed to treat cystoid macular edema (CME) from various etiologies over 12 months in vitrectomized and nonvitrectomized eyes. Methods. This multicenter retrospective cohort study included 112 patients with CME secondary to retinal diseases treated pro re nata (PRN) with a 0.7 mg intravitreal dexamethasone implant for 12 months. The BCVA, CRT, adverse events, safety data, and number of implants were recorded. Results. Vitrectomized and nonvitrectomized eyes received means of three implants and one implant, respectively, over 12 months (P < 0.001). The mean BCVA of all patients improved from 0.13 at baseline to 0.33 (P < 0.001) 12 months after one (P = 0.001), two (P = 0.041), and three (P < 0.001) implants but not four implants (P = 0.068). The mean baseline CRT decreased significantly (P < 0.001) from 463 to 254 microns after 12 months with one (P < 0.001), two (P = 0.002), and three (P = 0.001) implants but not with four implants (P = 0.114). The anatomic and functional outcomes were not significantly different between vitrectomized and nonvitrectomized eyes. Increased IOP was the most common adverse event (23.2%). Conclusions. Dexamethasone implant administered PRN improved VA and decreased CRT in CME, with possible long-term clinically relevant benefits for treating CME from various etiologies. Vitrectomized eyes needed more implants compared with nonvitrectomized eyes.

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.

Short-term Efficacy of Intravitreal Dexamethasone Implant in Vitrectomized Eyes with Recalcitrant Diabetic Macular Edema and Prior Anti-VEGF Therapy

Purpose:

To determine the efficacy of an intravitreal dexamethasone implant (IDI) for diabetic macular edema (DME) in vitrectomized eyes.

Methods:

This interventional retrospective consecutive case series included vitrectomized eyes undergoing IDI placement for treatment of recalcitrant DME between June 2011 and June 2014. All patients had previously received anti-VEGF therapy (ranibizumab or bevacizumab). Primary endpoints were changes in visual acuity (VA) and central retinal thickness (CRT) from baseline values one month after device implantation. Secondary endpoints were VA and CRT changes at 3 months.

Results:

A total of 8 eyes of 8 patients met the inclusion criteria. One month after IDI placement, there was a significant (p = 0.01) improvement in VA from 0.79 ± 0.52 logMAR (20/123 Snellen equivalent) to 0.64 ± 0.55 logMAR (20/88), meanwhile CRT improved from 455.75 ± 123.19 to 295.00 ± 90.39 μm (p = 0.02). These findings persisted at 3 months.

Conclusion:

In vitrectomized eyes previously treated with anti-VEGF agents for recalcitrant DME, implantation of the IDI appears to be efficacious in improving VA and CRT at 1-month with the observed benefits persisting for at least for 3 months.

Efficacy and Safety of a Dexamethasone Implant in Patients with Diabetic Macular Edema at Tertiary Centers in Korea

Purpose. To evaluate the real-world efficacy and safety of the dexamethasone implant (DEX implant) in patients with diabetic macular edema (DME). Methods. Retrospective, multicenter, and noncomparative study of DME patients who were treated with at least one DEX implant. A total of 186 eyes from 165 patients were included. Best-corrected visual acuity (BCVA), central retinal thickness (CRT), complications, and number of retreatments were collected. Data at baseline and monthly for 6 months were analyzed. Results. The average baseline BCVA and CRT were 0.60 LogMAR and 491.6 μm, respectively. The mean BCVA improved until 3 months and then decreased up to 6 months of follow-up (0.53, 0.49, and 0.55 LogMAR at 1, 3, and 6 months; p = 0.001, <0.001, and 0.044, resp.). The change of mean CRT was similar to BCVA (345.0, 357.7, and 412.5 μm at 1, 3, and 6 months, p < 0.001, <0.001, and <0.001, resp.). 91 eyes (48.9%) received additional treatment with anti-VEGF or DEX implant. The average treatment-free interval was 4.4 months. In group analyses, the DEX implant was more effective in pseudophakic eyes, DME with subretinal fluid (SRF), or diffuse type. Conclusions. Intravitreal dexamethasone implants are an effective treatment for patients with DME, most notably in pseudophakic eyes, DME with SRF, or diffuse type. A half of these patients require additional treatment within 6 months.

Long-term efficacy and safety of intravitreal dexamethasone implant for the treatment of diabetic macular edema

PURPOSE

To evaluate the long-term efficacy and safety of the dexamethasone intravitreal implant Ozurdex® in the treatment of diabetic macular edema (DME).

METHODS

This was a retrospective noncomparative study. A total of 23 patients with DME followed for at least 12 months were included. All patients were treated with at least 2 Ozurdex® injections for the treatment of DME. Best-corrected visual acuity, central retinal thickness, intraocular pressure (IOP), and cataract progression were recorded over 12 months.

RESULTS

From baseline, the mean decrease in central retinal thickness was 315.9 µm at the 12th month and the mean best-corrected visual acuity improvement from baseline was 8.7 letters. Ozurdex® is administered via the extended release system Novadur®. Its efficacy extends beyond 4 months with a single injection and permits allows good stabilization until the 12th month, with 2.13 injections during this period. An increase in IOP was observed in 13.1% of patients and all were managed using topical IOP-lowering medications. No glaucoma or cataract surgery was necessary, and no endophthalmitis was reported.

CONCLUSIONS

In real-life clinical practice, Ozurdex® has anatomical and functional effectiveness for the treatment of DME. Side effects were rare and manageable in our practice.

Treatment of Non-infectious Uveitic Macular Edema with the Intravitreal Dexamethasone Implant

PURPOSE

To describe the clinical outcome of phakic eyes with macular edema (ME) due to non-infectious uveitis treated with a dexamethasone intravitreal implant.

METHODS

A retrospective analysis of 41 eyes treated with a total of 58 dexamethasone intravitreal implants was conducted. Best corrected visual acuity (BCVA), central retinal thickness (CRT) and complications data were collected.

RESULTS

One month after the first implant, even as CRT improved significantly in most eyes (p<0.001), 31.7% showed no improvement in BCVA. At 6 months post-implantation, CRT and BCVA had deteriorated in up to 70% of patients. Thirteen eyes were re-implanted, with a similar effect to that of the first implant. Ocular hypertension developed in 36.2% of eyes, and three eyes had cataract surgery, all in eyes with repeated implants.

CONCLUSIONS

The dexamethasone intravitreal implant can be safely used to treat ME due to non-infectious uveitis, but with a limited and short effect on BCVA.

Effect of Posterior Subtenon Triamcinolone Acetonide Injection on Diabetic Macular Edema Refractory to Intravitreal Bevacizumab Injection

Purpose

To evaluate the effects of posterior subtenon triamcinolone acetonide injection on refractory diabetic macular edema (DME) after intravitreal bevacizumab (IVB) injection failure.

Methods

Patients with DME and central subfield thickness (CST) >300 µm who did not respond to IVB injections were retrospectively included. Specifically, we enrolled patients who were diagnosed with refractory DME and who experienced an increase in CST after 1 to 2 IVB injections or no decrease after ≥3 consecutive IVB injections. One clinician injected 20 mg of triamcinolone acetonide into the posterior subtenon space. All patients received ophthalmic examinations at baseline and at 2, 4, and 6 months post-baseline. Examinations included Snellen visual acuity, intraocular pressure, and spectral-domain optical coherence tomography.

Results

Forty eyes of 34 patients were included. The average baseline CST was 476 µm. The average CST decreased to 368 µm at 2 months, 374 µm at 4 months, and 427 µm at 6 months (p < 0.001 for all results, Wilcoxon signed-rank test). The average intraocular pressure increased from 15.50 to 16.92 mmHg at 2 months but decreased to 16.30 mmHg at 4 months and 15.65 mmHg at 6 months. Logarithm of the minimum angle of resolution visual acuity improved from 0.56 to 0.50 at 2 months (p = 0.023), 0.50 at 4 months (p = 0.083), and 0.48 at 6 months (p = 0.133, Wilcoxon signed-rank test). No complications were detected.

Conclusions

Posterior subtenon triamcinolone acetonide is an effective and safe treatment for reducing CST in DME refractory to IVB.

New Diagnostic and Therapeutic Approaches for Preventing the Progression of Diabetic Retinopathy

Diabetic retinopathy (DR) is a severe sight-threatening complication of diabetes mellitus. Retinal laser photocoagulation, antivascular endothelial growth factors, steroid therapy, and pars plana vitrectomy are now used extensively to treat advanced stages of diabetic retinopathy. Currently, diagnostic devices like ultrawide field fundus fluorescein angiography and the improvement of optical coherence tomography have provided quicker and more precise diagnosis of early diabetic retinopathy. Thus, treatment protocols have been modified accordingly. Various types of lasers, including the subthreshold micropulse laser and RPE-targeting laser, and selective targeted photocoagulation may be future alternatives to conventional retinal photocoagulation, with fewer complications. The new developed intravitreal medications and implants have provided more therapeutic options, with promising results.

Diabetic Macular Edema Pathophysiology: Vasogenic versus Inflammatory

Diabetic macular edema (DME) can cause blindness in diabetic patients suffering from diabetic retinopathy (DR). DM parameters controls (glycemia, arterial tension, and lipids) are the gold standard for preventing DR and DME. Although the vascular endothelial growth factor (VEGF) is known to play a role in the development of DME, the pathological processes leading to the onset of this disease are highly complex and the exact sequence in which they occur is still not completely understood. Angiogenesis and inflammation have been shown to be involved in the pathogenesis of this disease. However, it still remains to be clarified whether angiogenesis following VEGF overexpression is a cause or a consequence of inflammation. This paper provides a review of the data currently available, focusing on VEGF, angiogenesis, and inflammation. Our analysis suggests that angiogenesis and inflammation act interdependently during the development of DME. Knowledge of DME etiology seems to be important in treatments with anti-VEGF or anti-inflammatory drugs. Current diagnostic techniques do not permit us to differentiate between both etiologies. In the future, diagnosing the physiopathology of each patient with DME will help us to select the most effective drug.