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

Diabetic Macular Oedema Guidelines: An Australian Perspective

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

A Comparison of Ocular Complications after 0.7 mg Dexamethasone Implant versus 2 mg of Intravitreal Triamcinolone in Vitrectomized Eyes

OBJECTIVE

To compare the rates of complications in eyes that received a dexamethasone (DEX) implant (0.7 mg) or intravitreal triamcinolone (IVT) (2 mg) to treat postvitrectomy macular edema (ME).

DESIGN

Retrospective, comparative, case series.

SUBJECTS

A total of 148 eyes (147 patients); 75 eyes (75 patients) in the DEX group and 73 eyes (72 patients) in the IVT group.

METHODS

The medical records of patients who received an intravitreal DEX 0.7 mg (Ozurdex) or triamcinolone (2 mg) (Triesence) for postvitrectomy ME between July 2014 and December 2021 with a minimum follow-up of 3 months were reviewed. Ocular hypotony and ocular hypertension were defined as intraocular pressure of < 6 mmHg and > 24 mmHg, respectively.

MAIN OUTCOME MEASURES

The rates of complications.

RESULTS

The follow-up duration was 2.5 ± 1.6 years, with no significant difference between the groups (P = 0.398). The rate of transient ocular hypotony per eye and per injection was significantly higher in the DEX group (10 eyes [13%], 30 of 443 injections [7%]) compared with the IVT group (2 eyes [3%], 2 of 262 injections [0.8%]) (P = 0.039 and < 0.001, respectively). Mean visual acuity significantly decreased at the time of ocular hypotony (P = 0.031), but returned to preinjection level after resolution of the hypotony after a median of 12 days. The incidence of ocular hypertension was higher in the DEX group (23 eyes [31%]) than the IVT group (16 eyes [22%]), but this was not statistically significant (P = 0.307). Ocular hypertension was controlled with observation or topical medication. There were no between-group differences in the incidence of vitreous hemorrhage (DEX, 3 eyes [4%]; IVT, 1 eye [1%]; P = 0.632) or rhegmatogenous retinal detachment (DEX, 3 eyes [4%]; IVT, 0 eyes [0%]; P = 0.253). Four eyes (5%) experienced migration of the DEX implant into the anterior chamber. No eye developed endophthalmitis.

CONCLUSION

The incidence of ocular hypotony, which causes transient visual impairment, was significantly higher in vitrectomized eyes treated with DEX compared with eyes treated with IVT. Injections other than the inferotemporal quadrant or rotating injection sites may be recommended.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Efficacy and safety of the dexamethasone implant in vitrectomized and nonvitrectomized eyes with diabetic macular edema: A systematic review and meta-analysis

Purpose: To compare the efficacy and safety of the intravitreal dexamethasone (DEX) implant for the treatment of diabetic macular edema (DME) in vitrectomized and nonvitrectomized eyes.

Methods: We performed a literature search in four electronic databases (PubMed, EMBASE, MEDLINE, and Cochrane Library) from inception to 22 May 2022. Studies comparing the efficacy of the DEX implant in vitrectomized and nonvitrectomized eyes with DME with at least 3 months of follow-up were included. The main outcomes included comparison of the mean change in the best-corrected visual acuity (BCVA) and central macular thickness (CMT) from baseline to different follow-up endpoints between the vitrectomized and nonvitrectomized groups. The secondary outcomes were the mean duration of action for the first DEX implantation and the number of required injections throughout the follow-up period. Safety data were collected and compared.

Results: The final analysis included 7 studies involving 582 eyes, 208 vitrectomized eyes and 374 nonvitrectomized eyes. The mean between-group differences in BCVA improvement were not significant at any endpoint, with averages difference of −0.07 logarithm of the minimum angle of resolution (logMAR) (p = 0.088) at 1 month, −0.03 logMAR (p = 0.472) 3 months, −0.07 logMAR (p = 0.066) 6 months, and −0.04 logMAR (p = 0.486) 12 months. The mean between-group differences in CMT reduction were not statistically significant, with mean differences of 7.17 μm (p = 0.685) at 1 month, 20.03 μm (p = 0.632) 3 months, −1.80 μm (p = 0.935) 6 months, and −25.65 μm (p = 0.542) 12 months. However, the vitrectomized group had a significantly shorter duration of action during the first DEX implantation than the nonvitrectomized group, with a mean difference of 0.8 months (p = 0.005). No significant between-group differences were detected for the number of required injections or safety profile.

Conclusion: This meta-analysis showed similar efficacy and safety of the sustained-release DEX intravitreal implant for vitrectomized and nonvitrectomized eyes with DME. The intravitreal DEX implant could be considered an effective choice for DME treatment in eyes with prior vitrectomy.

One-Month Outcomes of Intravitreal Anti-VEGF vs. Dexamethasone Implant in the Treatment of Diabetic Macular Edema in Vitrectomized Eyes

Objectives

To compare short-term effect of intravitreal ranibizumab with dexamethasone implant for diabetic macular edema (DME) in vitrectomized eyes.

Methods

Single-center, prospective, randomized study of vitrectomized eyes with DME. Study eyes were divided into two groups, receiving ranibizumab (IVV group, n = 35 eyes) or dexamethasone implant (IVD group, n = 35 eyes) respectively. Patients were evaluated at baseline, Week 1 and Month 1. The main outcome measures included best-corrected visual acuity (BCVA), central retinal thickness (CRT) and intraocular pressure (IOP).

Results

BCVA and CRT were similar in the two groups at baseline. At Week 1, the CRT improvement was significant in two groups (P = 0.041 in IVV group, P = 0.030 in IVD group), but at Month 1, only IVD group had significant improvement in CRT (P < 0.001). And BCVA gains were significant at Week 1 (P = 0.029) and Month 1 (P = 0.001) in IVD group, whereas IVV group did not show significant BCVA gains (P = 0.056 at Week1, P = 0.166 at Month 1). The changes of BCVA and CRT were significantly higher in IVD group than IVV group at Month1, but the changes were not significant at Week1.

Conclusions

Comparing to anti-VEGF therapy, DEX implant is more effect in improving BCVA and reducing CRT in vitrectomized eyes at 1 month, which indicated DEX implant is a better strategy.

CLINICAL FEATURES OF INTRAVITREAL DEXAMETHASONE IMPLANTATION IN VITRECTOMIZED EYES OF PATIENTS WITH DIABETIC MACULAR EDEMA

PURPOSE

To identify the clinical outcomes of intravitreal dexamethasone implantation (IVD) in previously vitrectomized eyes of patients with diabetic macular edema.

METHOD

We performed a retrospective observational study. We recorded central subfield thickness, best-corrected visual acuity, and intraocular pressure up to 12 months after IVD implant placement. We compared the duration of IVD action, intraocular pressure trends, and the prevalence of ocular hypertension after the first IVD treatment of nonvitrectomized and vitrectomized eyes. We also compared the central subfield thickness, best-corrected visual acuity, number of IVD treatments, and prevalence of ocular hypertension between the 2 groups after 12 months.

RESULTS

We found no significant between-group differences in the central subfield thickness, best-corrected visual acuity, or the prevalence of ocular hypertension during treatment. However, the duration of action of the first IVD treatment was significantly shorter in vitrectomized eyes, and these eyes required more IVD treatments during the 12-month follow-up period. The maximal average intraocular pressure was observed at 2 months after the first IVD treatment in the nonvitrectomized group, but 1 month after the first IVD treatment in the vitrectomized group.

CONCLUSION

These findings suggest that the IVD pharmacokinetics and pharmacodynamics differ between vitrectomized and nonvitrectomized eyes. Nevertheless, given the relatively long-lasting effectiveness of the treatment and the good clinical results, consecutive IVD treatments may be beneficial for patients with diabetic macular edema with previously vitrectomized eyes.

Comparison of Intravitreal Dexamethasone Implant and Ranibizumab in Vitrectomized Eyes with Diabetic Macular Edema

Purpose

This retrospective study aimed to compare the efficacy of intravitreal ranibizumab (IVR) and intravitreal dexamethasone implant (IDI) for pseudophakic vitrectomized eyes with diabetic macular edema (DME) in a single institution.

Methods

Pseudophakic vitrectomized eyes with treatment-naïve center-involved DME were enrolled, with one eye in each patient. They were divided into two groups: one group receiving IDI every 3 to 4 months and another group receiving IVR using 3 monthly plus treat-and-extend injections, all with monthly follow-up for 6 months. Switch of intravitreal drugs or deferred macular laser was not allowed. Primary outcome measures included change in central foveal thickness (CFT) in 1 mm by spectral-domain optical coherence tomography and best-corrected visual acuity (BCVA) at Month 6.

Results

Twenty-two eyes were included in the IDI group and 26 eyes in the IVR group. The baseline demographics, glycosylated hemoglobin level, intraocular pressure (IOP), BCVA, and CFT did not significantly differ (p > 0.05). Compared to baseline data, CFT decreased and BCVA improved significantly after either IDI or IVR at Month 6 (p < 0.05). Significantly better mean final BCVA (0.38 logMAR vs. 0.62 logMAR, p=0.04), more mean visual gain (−0.30 logMAR vs. −0.15 logMAR, p=0.02), lower mean final CFT (310.9 μm vs. 384.2 μm, p=0.04), and larger mean CFT decrease (−150.0 μm vs. −60.1 μm, p=0.03) were found in the IDI group compared to those in the IVR group. A smaller mean treatment number (2.6 vs. 5.6, p < 0.001) and higher rate of postinjection ocular hypertension requiring topical hypotensive agent therapy (27.3% vs. 0%, p=0.0002) were demonstrated in the IDI group than those in the IVR group.

Conclusion

We concluded that IDI and IVR can both effectively treat vitrectomized eyes with DME. Dexamethasone implants had significantly better visual/anatomical improvement, smaller treatment number, and higher rate of elevated IOP after injection than IVR in pseudophakic vitrectomized eyes with DME in a 6-month period.

Switching to intravitreal fluocinolone acetonide implant for refractory diabetic macular edema: 12- and 24-month results

PURPOSE

To report visual and anatomical outcomes of chronic/refractory diabetic macular edema (DME) treated with intravitreal fluocinolone acetonide implant.

SETTING

Retrospective, one arm, multicentric study.

METHOD

Between 2013 and 2018, 27 consecutive eyes of 25 patients with chronic/refractory DME were treated with a fluocinolone acetonide intravitreal implant. Best registered visual acuity (BRVA), central retinal thickness (CRT), and Goldmann tonometry intraocular pressure (IOP) were assessed at 12 and 24 months. The need for IOP lowering treatment as well as top-up therapy during the follow-up were also assessed.

RESULTS

The duration of DME prior to treatment in our study was 54 ± 24 months. The baseline mean BRVA of 0.7 ± 0.34 logMAR improved to 0.5 ± 0.3 (p = 0.01) at 12 months and 0.46 ± 0.3 (p = 0.04) at 24 months. At 12 months, BRVA improved in 14 eyes (52%), stabilized in 5 eyes (20%), and decreased in 3 eyes (11%). At 24 months, BRVA improved further in 6 eyes (24%), stabilized in 3 eyes (12%), and decreased in 6 eyes (24 %). Mean CRT decreased from 497 ± 176 to 349 ± 186 μm at 12 months (p = 0.0005) and to 267 ± 104 μm at 24 months (p = 0.001). Only five eyes required additional treatment for DME and only three eyes required treatment for raised IOP.

DISCUSSION

Our results show that the visual and the anatomical improvements achieved by a single injection of a fluocinolone acetonide implant were maintained up to 24 months with minimal additional therapy even in eyes with a long and heavy history; however, IOP monitoring remains essential.

Effectiveness and Safety of Coadministration of Intravitreal Dexamethasone Implant and Silicone Oil Endotamponade for Proliferative Diabetic Retinopathy with Tractional Diabetic Macular Edema

Purpose: To investigate the efficacy and safety of coadministered intravitreal dexamethasone (IVD) implant and silicone oil endotamponade during pars plana vitrectomy (PPV) for the treatment of proliferative diabetic retinopathy (PDR) with tractional diabetic macular edema (DME). Methods: In this prospective, controlled, and randomized clinical study, the eyes with PDR and vitreomacular traction syndrome that underwent PPV with silicone oil endotamponade were divided into 2 groups. Group 1 was defined as the control group, and no other procedures were performed. IVD was implanted to the eyes in Group 2. In both groups, panretinal photocoagulation was completed to the missed areas during PPV. All cases followed for 6 months, postoperatively. Retinal findings were followed with optical coherence tomography and fluorescein fundus angiography. Results: A total of 52 eyes of 52 patients were included in the study. Twenty-six eyes of 23 patients were included in both groups. The improvement in best corrected visual acuity was statistically significantly higher in Group 2 (P > 0.05). In the postoperative period, the DME development rate and intravitreal ranibizumab (IVR) injection requirement were significantly higher in Group 1 (P > 0.05). There was no statistically significant difference in the proliferative vitroretinopathy development rate between the groups (P < 0.05). Conclusion: Coadministration of IVD implant and silicone oil endotamponade to the eyes with PDR during vitrectomy seems to be safe and effective application and may decrease the rate of DME and the requirement of IVR injection.

Effect of dexamethasone intravitreal implant in vitrectomized and nonvitrectomized eyes of Taiwanese patients with treatment-naïve diabetic macular edema

BACKGROUND/PURPOSE

Vitrectomy may affect intravitreal drug clearance and efficacy for treating diabetic macular edema (DME). This study aimed to evaluate functional and anatomical outcomes of intravitreal dexamethasone (DEX) implant for vitrectomized and nonvitrectomized eyes with treatment-naïve DME in Taiwanese patients.

METHODS

In this retrospective single-center study, we reviewed treatment-naïve patients who received DEX implant monotherapy for center-involved DME from January 2015 to May 2017. Retreatments were provided at least 4 months apart as needed. The primary outcomes included changes from baseline in best-corrected visual acuity (BCVA) and central foveal thickness (CFT) at Month 6. Adverse events were recorded.

RESULTS

Twenty-seven eyes in 27 patients had prior vitrectomy and 43 eyes in 41 patients without vitrectomy. Baseline data were comparable. Overall, the improvements in BCVA and CFT were significant by 1 month post-treatment and sustained throughout the study (all p < 0.05). At Month 6, BCVA improved by 16.5 and 12.1 letters, and CFT reduced by 138.0 and 121.9 μm in vitrectomized and nonvitrectomized eyes, respectively, with a mean of 1.5 DEX implant injection. No significant differences in clinical outcomes were seen between the two groups (all p > 0.05). DEX implant injection was well tolerated. About 30% of patients had post-injection intraocular pressure value > 20 mmHg, and all were manageable with topical hypotensive agents, and no serious ocular complication was observed.

CONCLUSION

In this 6-month retrospective study, intravitreal DEX implant was effective in Taiwanese patients with treatment-naïve DME regardless of vitrectomy status.

Real Life Experience of Dexamethasone Implant in Refractory Diabetic Macular Oedema

Purpose

The purpose of this retrospective study was to examine the efficacy of dexamethasone implant in refractory diabetic macular oedema (DMO) in real life settings.

Methods

In all, 24 eyes of 22 patients that required treatment with single or multiple intravitreal dexamethasone implants for refractory DMO were included in the study. Patients having macular oedema for another retinal disease were excluded from the study. The patient data were collected and analyzed retrospectively. As a demographic data age, gender, the type of diabetes and the duration of DMO were collected. Changes in central foveal thickness and the number of hyper reflective spots (HRS) were analyzed with Heidelberg SD-OCT. Furthermore, the best-corrected visual acuity (BCVA) and changes in the intraocular pressure (IOP) were measured.

Results

In all, 50.0% of the eyes with baseline BCVA 0.45 (±2.4) lines in ETDRS LogMAR scale received only one implant during the follow-up of 332 (±79) days. At the end of the follow-up, BCVA was 0.26 (±2.0) lines. The other 50.0% of the eyes with baseline BCVA 0.64 (±3.0) lines received the second implant in 156 (±38) days. Central retinal thickness (CRT) at baseline was 333 (±44) μm in the eyes with only one implant and 497 (±125) μm in the eyes with 2 or more implants. IOP lowering medication was needed for 8.3% of the eyes. The decrease in the number of HRS was significant (8±17, p=0.048) in response to dexamethasone implantation.

Conclusion

The dexamethasone implant is a useful treatment in refractory DMO and HRS seen in the OCT might indicate inflammation in the retina.

Effectiveness of Intravitreal Dexamethasone Implant Treatment for Diabetic Macular Edema in Vitrectomized Eyes

Objectives:

To report the effectiveness and long-term outcomes of intravitreal dexamethasone implantation for diabetic macular edema (DME) in vitrectomized eyes

Materials and Methods:

Medical records of patients were retrospectively reviewed. Time of pars plana vitrectomy (PPV), PPV indications, interval between DEX injection and PPV, other intravitreal treatment prior to DEX application, best corrected visual acuity (BCVA), intraocular pressure (IOP), and central retinal thickness (CRT) measured by optical coherence tomography were recorded.

Results:

Seventeen eyes of 17 patients were included in the study. The mean follow-up after DEX injection was 21±2.4 months (12-43 months). The female/male ratio was 11/6. Mean age was 60.7 years (46-70 years). Sixteen eyes (94.1%) were pseudophakic at the time of DEX treatment. The most common indication for PPV was tractional retinal detachment (8 eyes, 47.1%). Ten eyes (58.8%) received a single injection and a total of 30 DEX implantations were performed. Mean BCVA was 0.77 logarithm of the minimum angle of resolution (logMAR) units before the first injection and improved to 0.64, 0.68 and 0.66 logMAR after 1, 3 and 6 months, respectively (p<0.01). CRT decreased significantly from 452 µm at baseline to 310, 368±34 and 375 µm after 1, 3 and 6 months, respectively (p<0.04). Mean IOP was 16±1.2 mmHg at baseline and 18.2, 18.8 and 18.5 mmHg after 1, 3, and 6 months (p>0.05). Two eyes (%8) received topical anti-glaucoma medication (IOP≥25 mmHg). Similar results were observed in eyes receiving repeated DEX injections.

Conclusion:

Intravitreal DEX injection treatment seems to be effective for improving BCVA and decreasing CRT in vitrectomized eyes with DME. This effect seemed to last for 6 months in most eyes, but maximized at 3 months. Patients with repeated injections often require injection before 6 months.

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.

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.