Vitrectomy for diabetic macular oedema

Vitrectomy as an Adjunct to Treat-and-Extend Anti-VEGF Injections for Diabetic Macular Edema: The Vitrectomy in Diabetic Macular Oedema (VIDEO) Randomized Clinical Trial

Importance

There are reported benefits from vitrectomy for diabetic macular edema (DME); however, data precede anti-vascular endothelial growth therapy (VEGF) therapy, supporting a need to assess the current role of vitrectomy.

Objective

To determine rates of recruitment and efficacy outcomes of vitrectomy plus internal limiting membrane (ILM) peeling adjunctive to treat-and-extend (T&E) anti-VEGF injections for diabetic macular edema (DME).

Design, Setting, and Participants

This was a single-masked, multicenter randomized clinical trial at 21 sites in the United Kingdom from June 2018 to January 2021, evaluating single eyes of treatment-naive patients with symptomatic vision loss from DME for less than 1 year. Inclusion criteria were best-corrected visual acuity (BCVA) Early Treatment Diabetic Retinopathy Study letter score greater than 35 (approximate Snellen equivalent, 20/200 or better) and central subfield thickness (CST) greater than 350 μm after 3 monthly intravitreal injections of ranibizumab or aflibercept. Data analysis was performed in July 2023.

Interventions

Patients were randomized 1:1 into vitrectomy plus standard care or standard care alone and further stratified into groups with vs without vitreomacular interface abnormality. Both groups received a T&E anti-VEGF injection regimen with aflibercept, 2 mg, or ranibizumab, 0.5 mg. The vitrectomy group additionally underwent pars plana vitrectomy with epiretinal membrane or ILM peel within 1 month of randomization.

Main Outcomes and Measures

Rate of recruitment and distance BCVA. Secondary outcome measures were CST, change in BCVA and CST, number of injections, rate of completed follow-up, and withdrawal rate.

Results

Over 32 months, 47 of a planned 100 patients were enrolled; 42 (89%; mean [SD] age, 63 [11] years; 26 [62%] male) completed 12-month follow-up visits. Baseline characteristics appeared comparable between the control (n = 23; mean [SD] age, 66 [10] years) and vitrectomy (n = 24; mean [SD] age, 62 [12] years) groups. No difference in 12-month BCVA was noted between groups, with a 12-month median (IQR) BCVA letter score of 73 (65-77) letters (Snellen equivalent, 20/40) in the control group vs 77 (67-81) letters (Snellen equivalent, 20/32) in the vitrectomy group (difference, 4 letters; 95% CI, -8 to 2; P = .24). There was no difference in BCVA change from baseline (median [IQR], -1 [-3 to 2] letters for the control group vs -2 [-8 to 2] letters for the vitrectomy group; difference, 1 letter; 95% CI, -5 to 7; P = .85). No difference was found in CST changes (median [IQR], -94 [-122 to 9] μm for the control group vs -32 [-48 to 25] μm for the vitrectomy group; difference, 62 μm; 95% CI, -110 to 11; P = .11).

Conclusions and Relevance

Enrollment goals could not be attained. However, with 47 participants, evidence did not support a clinical benefit of vitrectomy plus ILM peeling as an adjunct to a T&E regimen of anti-VEGF therapy for DME.

Trial Registration

isrctn.org Identifier: ISRCTN59902040.

The impact of Vitreo-Macular interface abnormalities on the response to Anti-VEGF therapy for centre involving diabetic macular oedema

BACKGROUND

The influence of Vitreomacular Interface Abnormalities (VMIA) such as Epiretinal Membrane (ERM) and/or vitreomacular traction (VMT) on the response of patients with Centre Involving Diabetic Macular Edema (CIDME) to standard of care Anti-VEGF medications is under-researched. The aims of this study were: 1) To determine the incidence of VMIA at baseline and 12 months amongst treatment naive patients commencing anti-VEGF treatment 2) To compare the response to Anti-VEGF medications at 3 monthly intervals for 12 months in a large cohort of patients with and without VMIA on their baseline OCT scan. Response was determined in terms of: number of injections, central macular thickness and visual acuity.

METHODS

A retrospective case notes review of treatment naïve patients with newly diagnosed CIDME. Included patients had been commenced on intravitreal Anti-VEGF injections (ranibizumab or aflibercept) at a single centre. Inclusion criteria were: treatment naïve DME patients with a CMT of 400μ or more receiving anti-VEGF treatment with at least 12 months follow up and in whom macular OCT scans and visual acuity (VA) measurements were available within two weeks of baseline, 3, 6, 9 and 12 months. Exclusion criteria included: previous intravitreal therapy, previous vitrectomy, cataract surgery during the follow-up period, concurrent eye conditions affecting vision or CMT.

RESULTS

119 eyes met the inclusion criteria and underwent analysis. Groups were comparable in their baseline demographics. Baseline CMT measurements were comparable at baseline (417μ and 430μ in the No-VMIA and VMIA groups respectively) and improved to approximately 300μ in both groups. From 6 months CMT continued to improve in the no-VMIA while progressively deteriorating in the VMIA group. Change in CMT was statistically different at 12 months between the 2 groups (108μ and 79μ, p= 0.04). There was a mean of 7 injections after 12 months.

CONCLUSION

Our study has shown a 46% incidence of VMIA amongst patients newly diagnosed with centre involving DME undergoing treatment with anti-VEGF injections. We have also demonstrated a significant difference in CMT and VA response to anti-VEGF treatment in patients with and without VMIA. Initial response was similar between the 2 groups up until 6 months. From 6 to 12 months significant differences in treatment response emerged. Differences in clinical response between patients with and without VMIA may help guide further prospective controlled studies and optimise treatment strategies.

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.

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

BACKGROUND

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

METHODS

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

DISCUSSION

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

TRIAL REGISTRATION

ClinicalTrials.gov NCT05728476. Registered on 15 February 2023.

Vitrectomy with ILM peeling in diabetic macular edema in one eye vs. intravitreal anti-VEGF injections in the second eye: a comparative study

PURPOSE

The aim of this study was to compare the results of vitrectomy performed in patients' worse eyes with diabetic macular edema to the results of continuous anti-VEGF treatment performed in patients' fellow eyes.

METHODS

A retrospective interventional study of 14 patients with diabetic macular edema in both eyes. The better eye was always qualified for aflibercept injections (group 1), and the worse eye was scheduled for vitrectomy (group 2). The follow-up lasted 12 months. The following parameters were measured: visual acuity (V), central retinal thickness (CRT), maximum retinal thickness (MRT), central choroidal thickness (CCT), superficial fovea avascular zone (sFAZ) and deep fovea avascular zone (dFAZ), and vessel density at the level of superficial (sVD) and deep (dVD) retinal vessels.

RESULTS

None of the analyzed factors differed between groups with statistical significance at any timepoint. The time of recovery of vision was identical in both eyes (F = 0.91, p = 0.449). The final sFAZ was significantly smaller for group 2 (median 196 μm) than for group 1 (median 375 μm; U = 101.0; p = 0.022; r = 0.44).

CONCLUSION

Both techniques resulted in similar improvements in visual acuity and decreases in CRT after 1 year. sFAZ decreased in all eyes, with a higher extent after vitrectomy.

The influence of retinal oxygen saturation and choroidal volume on postoperative outcomes in patients with epiretinal membrane

Purpose

To investigate the effects of vitrectomy (Vy) with or without same time cataract surgery and membrane plus internal limiting membrane peeling (MP+ILMP) on retinal oxygenation and choroidal volume and their role on postoperative outcome.

Methods

Thirty‐two eyes were included in this prospective clinical study. All patients received 23 gauge Vy+MP+ILMP without endotamponade. Additional cataract surgery was performed in 14 patients. Follow‐up visits were scheduled at day 1, week 1, month 1 and month 3. At each visit, best corrected visual acuity (BCVA) using ETDRS charts (except at day 1), oxygenation of retinal vessels using the Oxymap T1, and optical coherence tomography (OCT, Heidelberg Spectralis) was performed.

Results

Mean BCVA increased significantly from 73 ± 11 letters to 77 ± 7 letters at month 3 (p = 0.02). Mean central retinal thickness (CRT) decreased from 456 ± 84 µm at baseline to 418±58µm (p = 0.01 baseline versus month 3). In the cataract surgery group, CRT was higher at month 3 than in the group without (400 ± 58 µm versus 441 ± 51 µm; p = 0.007). There was no statistically significant difference in choroidal volume or oxygenation of retinal vessels between groups (additional cataract surgery versus vitrectomy alone). Oxygenation of retinal arteries tended to decrease at day 1 followed by an increase, but the changes did not reach the level of significance (p = 0.29 baseline versus month 3). Oxygenation of retinal veins increased significantly (p = 0.02 baseline versus month 1; p = 0.04 baseline versus month 3, accordingly). There was a significant negative correlation (Spearman correlation coefficient rs = −0.35, p = 0.047) between visual acuity and oxygenation of retinal veins at month 3. No statistically significant correlation was found between CRT and oxygenation of neither retinal arteries nor veins. Choroidal volume (CV) of the central mm did not change significantly during the study period (baseline: 0.203 ± 0.04 mm³, median: 0.206, month 3: 0.205 ± 0.04 mm³, p = 0.54). There was no statistically significant effect of choroidal volume at baseline on postoperative clinical outcomes (change in BCVA estimate [95% CI]: 7 [−76; 90], p = 0.86; change in CRT: 147 [−577; 871], p = 0.68).

Conclusion

Oxygen saturation may affect the visual acuity outcome but not the CRT in patients after vitrectomy for epiretinal membrane. Choroidal thickness had no statistically significant influence on the study outcomes. Further studies are needed to evaluate if the measurement of retinal oxygenation may be helpful in the decision for surgery.

Pars Plana Vitrectomy with Internal Limiting Membrane Peeling for Treatment-Naïve Diabetic Macular Edema: A Prospective, Uncontrolled Pilot Study

Purpose

To report the outcomes in subjects undergoing pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling for the management of treatment-naïve diabetic macular edema (DME).

Methods

Ten treatment-naïve subjects with non-proliferative diabetic retinopathy prospectively underwent PPV with ILM peeling for the treatment of DME at a single university-affiliated institution. The preoperative features, intraoperative details and postoperative outcomes were collected and analyzed.

Results

All 10 subjects underwent PPV with ILM peeling without significant intraoperative or postoperative complications at 6 months follow-up. Visual acuity improved from a baseline of 0.74 (95% CI: 0.48–1.0) logMAR (Snellen 20/110) to 0.46 (95% CI: 0.3–0.62) logMAR (Snellen 20/58) at 6 months follow-up (p=0.045). Optical coherence tomography central macular thickness reduced from a baseline of 456 (95% CI: 394.7–516.4) microns to 316.8 (95% CI: 275.9–357.7) microns at 6 months follow-up (p < 0.001).

Conclusion

This pilot study suggests that PPV with ILM peeling may be a viable treatment option for the management of treatment naïve DME in subjects with non-proliferative diabetic retinopathy. Development of a randomized controlled trial may be justified to validate the results of this study.

Clinicaltrials.gov Identifier #

NCT03660345.

En face image-based classification of diabetic macular edema using swept source optical coherence tomography

This retrospective study was performed to classify diabetic macular edema (DME) based on the localization and area of the fluid and to investigate the relationship of the classification with visual acuity (VA). The fluid was visualized using en face optical coherence tomography (OCT) images constructed using swept-source OCT. A total of 128 eyes with DME were included. The retina was segmented into: Segment 1, mainly comprising the inner nuclear layer and outer plexiform layer, including Henle’s fiber layer; and Segment 2, mainly comprising the outer nuclear layer. DME was classified as: foveal cystoid space at Segment 1 and no fluid at Segment 2 (n = 24), parafoveal cystoid space at Segment 1 and no fluid at Segment 2 (n = 25), parafoveal cystoid space at Segment 1 and diffuse fluid at Segment 2 (n = 16), diffuse fluid at both segments (n = 37), and diffuse fluid at both segments with subretinal fluid (n = 26). Eyes with diffuse fluid at Segment 2 showed significantly poorer VA, higher ellipsoid zone disruption rates, and greater central subfield thickness than did those without fluid at Segment 2 (P < 0.001 for all). These results indicate the importance of the localization and area of the fluid for VA in DME.

Pars Plana Vitrectomy versus Intravitreal Injection of Ranibizumab in the Treatment of Diabetic Macular Edema Associated with Vitreomacular Interface Abnormalities

Purpose

To compare the efficacy of pars plana vitrectomy (PPV) versus intravitreal injection (IVI) of ranibizumab (RBZ) in the treatment of diabetic macular edema (DME) associated with vitreomacular interface abnormalities (VMIA).

Methods

The records of patients presenting with DME and VMIA throughout 2016 to 2018 were retrospectively analyzed. The patients were divided into 2 groups: group I received IVIs of RBZ and group II underwent PPV with internal limiting membrane peeling. The main outcome measures were the change in the LogMAR corrected distance visual acuity (CDVA) and central subfield thickness (CSFT) on optical coherence tomography over 6 months.

Results

At 6 months, mean CDVA improved by 0.22 ± 0.21 in group I patients (p < 0.001), while in group II, it improved only by 0.09 ± 0.22 (p < 0.115). Fifty-five percent of group I and 60% of group II patients had stable CDVA (within 2 lines from baseline) at 6 months. Significant improvement in vision (gain of 2 or more lines) was seen in 45% and 30%, respectively. Worsening of vision (loss of 2 or more lines) was seen only in 2 patients in group II, but none in group I. The mean CSFT improved significantly in both groups (by 162 µ and 216 µ, respectively; p < 0.001). The mean CSFT at 6 months was similar in both groups (354 µ and 311 µ, respectively; p=0.172).

Conclusions

Both treatments resulted in anatomical improvement of DME with concurrent VMIA. Visual improvement was more pronounced in the IVI group, although this may have been affected by other confounding factors.

Predictive factors of outcome of selective retina therapy for diabetic macular edema

PURPOSE

To investigate the predictive factors of clinical outcome of selective retina therapy (SRT) for diabetic macular edema (DME).

METHODS

This retrospective study included 22 eyes of 22 patients (15 males and 7 females), who were treated with SRT for DME at the Department of Ophthalmology of Osaka City University Hospital and observed at least 6 months after the treatment. The mean age was 64 years (range 40-81). Thirteen of the 22 eyes (59%) had a treatment history other than SRT before. SRT laser (527 nm, 1.7 µs, 100 Hz) was used for treatment. Changes in the best-corrected visual acuity (BCVA) (logMAR) and central macular thickness (CMT) in optical coherence tomography were examined at baseline, 3-month follow-up, and 6-month follow-up. Factors associated with the rate of change in CMT at 3 and 6 months after SRT were examined.

RESULTS

The mean BCVA (logMAR) was 0.26 ± 0.31, 0.22 ± 0.27 and 0.23 ± 0.29 at baseline, 3 months and 6 months, respectively (p = 0.15 at 3 months, 0.40 at 6 months; compared to baseline). The mean CMT was 502 ± 163, 493 ± 204, and 416 ± 185 μm at baseline, 3 months, and 6 months, respectively (p = 0.69 at 3 months, 0.01 at 6 months; compared to baseline). The multivariate analysis found a significant negative association with previous macular photocoagulation (p = 0.03) at 3 months and a positive association with a history of insulin use (p = 0.02) and previous panretinal photocoagulation (p = 0.03) at 6 months after SRT.

CONCLUSION

The CMT was significantly decreased at 6 months after SRT in DME. The history of insulin use and panretinal photocoagulation may positively and the history of macular photocoagulation may negatively affect the outcome of SRT, which must be considered when determining the therapeutic indications for SRT.

Submacular Injection of Ranibizumab as a New Surgical Treatment for Refractory Diabetic Macular Edema

Purpose

In this study, we describe a new surgical technique for the treatment of refractory DME. The technique consists of vitrectomy with ILM peeling with a subretinal injection of ranibizumab.

Methods

This is a prospective interventional noncomparative study including patients with refractory DME. Included patients were subjected to the new surgical technique of pars plana vitrectomy with subretinal injection of ranibizumab.

Results

The study included 19 eyes with refractory macular edema, in which this novel technique was attempted. There were 10 males and 9 females. The age of the patients ranged from 17 to 67 years with a mean of 55.58 ± 13.242 years. The duration of diabetes before enrollment in the study ranged from 7 to 25 years with a mean of 16.3 years. Preoperatively, the mean CMT of the eyes ranged from 352 to 883 microns with mean ± SD of 498.58 ± 152.16 microns. Postoperatively, this improved significantly to 373.5 ± 100.3, 355.9 ± 89.8, and 365.74 ± 120.12 microns at 1, 3, and 6 months, respectively (p ≤ 0.001 for all).

Conclusion

This novel surgical procedure of vitrectomy with ILM peeling with a subretinal injection of ranibizumab is effective in cases of refractory DME. The study has been registered in Contact ClinicalTrials.gov PRS Identifier: NCT03975088.

Diabetic macular edema: Evidence-based management

Diabetic macular edema (DME) is the most common cause of vision loss in patients with diabetic retinopathy with an increasing prevalence tied to the global epidemic in type 2 diabetes mellitus. Its pathophysiology starts with decreased retinal oxygen tension that manifests as retinal capillary hyperpermeability and increased intravascular pressure mediated by vascular endothelial growth factor (VEGF) upregulation and retinal vascular autoregulation, respectively. Spectral domain optical coherence tomography (SD-OCT) is the cornerstone of clinical assessment of DME. The foundation of treatment is metabolic control of hyperglycemia and blood pressure. Specific ophthalmic treatments include intravitreal anti-VEGF drug injections, intravitreal corticosteroid injections, focal laser photocoagulation, and vitrectomy, but a substantial fraction of eyes respond incompletely to all of these modalities resulting in visual loss and disordered retinal structure and vasculature visible on SD-OCT and OCT angiography. Efforts to close the gap between the results of interventions within randomized clinical trials and in real-world contexts, and to reduce the cost of care increasingly occupy innovation in the social organization of ophthalmic care of DME. Pharmacologic research is exploring other biochemical pathways involved in retinal vascular homeostasis that may provide new points of intervention effective in those cases unresponsive to current treatments.

Dexamethasone implant in silicone oil: in vitro behavior

Background

To determine the effect of the silicone on the dexamethasone intravitreal implant.

Methods

Basic, experimental, prospective and transversal study performed at the hospital “Nuestra Señora de la Luz” in Mexico City. One dexamethasone implant was placed in a test tube with 4 mL of each tamponade medium: 1000cS, 5000cS and heavy silicone oil; basic saline solution was used as the control medium. Photographs were taken weekly for 12 months. 200 µL samples were taken from each medium at 24 h, 1, 2 weeks and monthly for 12 months. ELISA test was performed to quantify dexamethasone release in every sample. An inflammatory stimulus was created and later exposed it to every sample in order to test their anti-inflammatory capacity by cytokine analysis using cytometric bead array. Statistically significant results were obtained with p < 0.05.

Results

Photographic follow-up showed disintegration of the implant in control medium. Implants in silicone oil suffered no changes during follow-up. Dexamethasone levels in control medium showed stability from month 2 to 12. Silicone oil mediums showed irregular dexamethasone release during the 1 year period. Dexamethasone in control medium had inhibitory effects on TNF-α starting at 24 h (p < 0.001) and remained stable. Dexamethasone in 1000cS silicone oil showed inhibitory effects from month 2 (p < 0.001) until month 6 (p < 0.001). Implants in denser silicone oils showed no inhibitory effects in any of the samples.

Conclusions

Denser mediums altered the implant pharmacokinetics and showed no anti-inflammatory effects even when concentrations were quantified at levels similar to control medium in vitro.

Effects of kallidinogenase in patients undergoing vitrectomy for diabetic macular edema

PURPOSE

To evaluate the effectiveness of the combination of vitrectomy with kallidinogenase for diabetic macular edema (DME).

METHODS

This study was designed as a prospective, randomized, multicenter study comparing 19 eyes of 19 patients who received 150 units of kallidinogenase administered a day for 52 weeks from the day after vitrectomy (study group) with 20 eyes of 20 patients who received no kallidinogenase (control group). The main outcome measurements included logMAR visual acuity and central foveal thickness (CFT) before surgery and at 3, 6, 9, and 12 months after vitrectomy.

RESULTS

During follow-up, 11 patients dropped out (six in the study group and five in the control group), leaving 28 eyes in 28 patients for analysis (13 in the study group and 15 in the control group). Visual acuity improved significantly at 12 months in both groups compared with before surgery. The degree of improvement did not differ significantly between the groups. At 12 months, the mean CFT decreased significantly in both groups, with no significant difference in the rate of change between the two groups. In the study group, the visual acuity and CFT significantly improved from 3 to 12 months and from 6 to 12 months, whereas these parameters did not continue to improve in the control group after 6 months (for visual acuity) or 3 months (for CFT).

CONCLUSION

After vitrectomy for DME, visual acuity and CFT improved significantly in both groups, but only patients treated with kallidinogenase continued to have significant improvement throughout the study period.

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

Purpose

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

Methods

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

Results

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

Conclusion

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

Ocriplasmin treatment for vitreomacular traction in real life: can the indication spectrum be expanded?

PURPOSE

To evaluate the efficacy of intravitreal ocriplasmin for the resolution of vitreomacular traction (VMT) with or without a full thickness macular hole (FTMH) in the clinical setting and to assess whether the indication spectrum of this treatment modality can be expanded beyond that of the MIVI-TRUST trials.

METHODS

The records of patients with VMT with or without FTMH, who were treated with intravitreal ocriplasmin were reviewed. Patients were divided in two groups. In the first group, VMT with or without FTMH was present without any other macular pathology. In the second group, VMT with or without FTMH occurred alongside of other macular disease including age-related macular degeneration, diabetic maculopathy and post-operative pseudophakic cystoid macular edema.

RESULTS

Release of the VMT was achieved in 12/20 patients (12/20 eyes) of the first group. 16 eyes in this group met 3 or more criteria known to be associated with favorable prognosis after intravitreal ocriplasmin treatment. No cases of release of the VMT were observed in the second group, which included 15 patients (15 eyes). Significant improvement of visual acuity and reduction of the central macular thickness was observed only in the subgroup of eyes which responded to treatment.

CONCLUSIONS

Concomitant macular pathology was a significant factor for treatment failure and we suggest that ocriplasmin should be regarded with caution in these cases. Careful patient selection for treatment with ocriplasmin using specific criteria in the clinical setting can provide superior results to those reported in the MIVI-TRUST trials.

Intravitreal ranibizumab for diabetic macular oedema in previously vitrectomized eyes

PURPOSE

There is little information about the efficacy of intravitreal vascular endothelial growth factor (VEGF) inhibition in vitrectomized eyes. This study aimed to evaluate the efficacy of anti-VEGF (ranibizumab) on diabetic macular oedema in previously vitrectomized eyes.

METHODS

A nationwide retrospective review of medical records from 2010 to 2013.

RESULTS

We identified 33 previously vitrectomized eyes in 28 patients treated with ranibizumab injections for diabetic macular oedema. Median follow-up was 323 days (interquartile range 72-1404 days). Baseline mean visual acuity was 0.57 logMAR (95% CI 0.13-1.01) before injections. After an average of 4.7 injections (range 1-15), mean visual acuity remained stable at 0.54 logMAR (95% CI 0.13-0.95) with a mean improvement of 0.03 (p = 0. 45, 95% CI -0.12 to 0.06). In 12 eyes (36%), visual acuity improved 0.1 logMAR or more, in 12 eyes (36%), vision was unchanged (gain or loss of 0-0.05 logMAR), and in nine eyes (27%), vision decreased 0.1 logMAR or more. Mean central foveal thickness (CFT) on optical coherence tomography (OCT) scan was 412 μm (95% CI 390-434 μm) before injections. After injections, the mean CFT decreased to 352 μm (95% CI 334-370 μm). The mean reduction in CFT was 14% (95% CI 4-24%, p = 0.01). Sixteen eyes (48.5%) became devoid of oedema on the last OCT scan. Despite the significant reduction in CFT, the visual acuity remained unchanged.

CONCLUSION

Intravitreal ranibizumab can be effective in previously vitrectomized eyes with diabetic macular oedema. However, the response is variable and should be carefully monitored.

Diabetic macular oedema

Diabetic macular oedema, characterised by exudative fluid accumulation in the macula, is the most common form of sight-threatening retinopathy in people with diabetes. It affects one in 15 people with diabetes resulting in more than 20 million cases worldwide. Few epidemiological studies have been done to specifically investigate risk factors for diabetic macular oedema, although poor glycaemic and blood pressure control are associated with the presence and development of the disorder. The pathophysiological processes begin with chronic hyperglycaemia, and interplay between vascular endothelial growth factor (VEGF) and inflammatory mediators. Non-invasive imaging using optical coherence tomography has allowed clinicians to detect mild levels of diabetic macular oedema in order to monitor progress and guide treatment. Although focal or grid laser photocoagulation was the traditional mode of treatment, intraocular pharmacotherapy with anti-VEGF agents is now the standard of care. However, these therapies are expensive and resource intensive. Emerging therapeutic strategies include improving efficacy and duration of VEGF suppression, targeting alternative pathways such as inflammation, the kallikrein-kinin system, the angiopoietin-Tie2 system, and neurodegeneration, and using subthreshold and targeted laser therapy. Ongoing research should lead to improvements in screening, diagnosis, and management of diabetic macular oedema.

Spectral Domain Optical Coherence Tomography Features and Classification Systems for Diabetic Macular Edema: A Review

Spectral domain optical coherence tomography (SD-OCT) is fast becoming the current standard of care for the detection and assessment of diabetic macular edema. With the application of SD-OCT for imaging of retinal microstructure and measurement of retinal thickness, new information regarding disease characteristics has been gathered, which was unrecognized previously. Retinal thickness measurements on SD-OCT have also been used for deciding the management and monitoring of the disease. Since its development, OCT has enhanced the understanding of retinal anatomical changes in diabetic retinopathy. Several authors have used SD-OCT to classify diabetic macular edema with the purpose of correlating the pathophysiology with disease severity. The classification systems have helped monitor the treatment efficacy and provide prognostic information on the treatment outcome. The following review article summarizes these classifications.

Vitrectomy for center-involved diabetic macular edema

PURPOSE

To determine the effect of vitrectomy for center-involved diabetic macular edema (CI-DME).

METHODS

This was a retrospective study of 53 eyes of 45 patients who had vitrectomy for CI-DME and were followed up for at least 12 months. Charts were reviewed for visual acuity (VA), central subfield mean thickness measured by optical coherence tomography, presurgical and postsurgical interventions for CI-DME, and number of office visits in the first 12 months after surgery. Preoperative spectral domain optical coherence tomography was performed on 38 patients, and they were graded for ellipsoid zone (EZ) intactness by three independent graders with assessment of agreement between graders using intraclass correlation coefficients and Bland-Altman analysis.

RESULTS

The median VA improved from 20/100 (interquartile range [IQR], 20/63-20/200) at baseline to 20/63 (IQR, 20/32-20/125) at 12 months. The median central subfield mean thickness improved from 505 μm (IQR, 389-597 μm) at baseline to 279 μm (IQR, 246-339 μm) at 12 months. Intergrader agreement for EZ intactness was moderate (intraclass correlation coefficients 0.4294-0.6356). There was no relationship between preoperative intactness of the EZ and the 12-month change in VA.

CONCLUSION

Vitrectomy consistently thins the macula in CI-DME and, on average, leads to clinically significant improvement in VA comparable in size to that reported with serial intravitreal anti-vascular endothelial growth factor injections. A large, comparative, prospective, randomized clinical trial of these two treatments is needed to determine which is more effective and cost-effective.

Minimally Invasive Microincision Vitrectomy Surgery with an Intraoperative Dexamethasone Implant for Refractory Diabetic Macular Edema

PURPOSE

To evaluate the 1-year results of 25-gauge microincision vitrectomy surgery (MIVS25) combined with intraoperative dexamethasone (DEX) implant for persistent diabetic macular edema (DME).

METHODS

This study enrolled patients who had a history of DME for ≥12 months and underwent MIVS25 and DEX implant injection. Best corrected visual acuity (BCVA) and central retinal thickness (CRT) were assessed postoperatively.

RESULTS

Eighteen eyes were included in the analysis. Preoperatively, logMAR BCVA was 0.90 and CRT was 594 µm on average. CRT decreased until the 3-month follow-up visit and tended to increase at 6 months, but stabilized at 12 months with additional treatments in five eyes at 5 months postoperatively. Statistically significant improvement in BCVA was noted 1 month after treatment and at each subsequent follow-up visit (p < 0.001).

CONCLUSION

MIVS25 combined with DEX implant injection might be utilized as an effective and safe alternative treatment for intractable DME.

VITRECTOMY WITH INTERNAL LIMITING MEMBRANE PEELING FOR TRACTIONAL AND NONTRACTIONAL DIABETIC MACULAR EDEMA: Long-term Results of a Comparative Study

PURPOSE

To compare the long-term outcomes of vitreomacular surgery in eyes with nontractional diabetic macular edema (DME) with those from eyes with tractional DME.

METHODS

Retrospective comparative study from 55 consecutive patients (73 eyes). Twenty eyes were operated on for tractional DME and 53 eyes for nontractional DME unresponsive to laser photocoagulation or triamcinolone intravitreal injections. The best-corrected visual acuity, the central macular thickness, and the surgical complications were analyzed.

RESULTS

The mean follow-up duration was 5.3 ± 2.4 years for the group with traction and 4.4 ± 1.7 years for the group without traction (P = 0.13). At 3 years, the mean logarithm of the minimum angle of resolution best-corrected visual acuity had improved significantly from 0.78 to 0.58 for the group without traction and from 0.75 to 0.45 for the group with traction (P < 0.001). At the final visit, there was no significant difference between the 2 groups in regard to visual or central macular thickness improvement (P = 0.447 and P = 0.742, respectively). The incidence of surgical complications was not significant between the two groups. The preoperative best-corrected visual acuity was the only predictive factor for the final best-corrected visual acuity.

CONCLUSION

The results of vitrectomy were not different in terms of anatomical and visual outcomes and surgical complications between eyes without tractional DME and eyes with tractional DME.

Ranibizumab for Visual Impairment due to Diabetic Macular Edema: Real-World Evidence in the Italian Population (PRIDE Study)

Purpose. An expanded access program (PRIDE study) in Italy to provide ranibizumab 0.5 mg to diabetic macular edema (DME) patients, prior to reimbursement. Methods. Open-label, prospective, phase IIIb study. Majority of patients were not treatment-naïve before enrollment. Patients received ranibizumab as per the EU label (2011). Safety was assessed by incidences of ocular/systemic adverse events (AEs) and serious AEs (SAEs) and efficacy in terms of visual acuity (VA) change from baseline (decimal score or Snellen (20/value)). Results. Overall, 515 patients (83.5%) completed the study. In unilateral/bilateral patients, commonly observed AEs were cardiac disorders (1.3%/1.3%) and nervous system disorders (1.3%/1.1%); SAEs were reported in 4.5%/4.8% of patients. Acute renal failure, lung carcinoma, and cardiac arrest were the causes of death in one unilateral and two bilateral patients. Ranibizumab improved/maintained VA (Snellen (20/value)/decimal scores) in both unilateral (up to −16.7/1.5) and bilateral patients (up to −23.6/1.2) at Month 5, with a mean of 4.15 and 4.40 injections, respectively. Overall, no difference was observed in the VA outcomes and treatment exposure between unilateral/bilateral patients. Conclusions. The PRIDE study provided early ranibizumab access to >600 Italian patients. Ranibizumab was well-tolerated and improved/maintained VA in 40.2%–68.8% patients, with no differences in case of unilateral or bilateral pathology. The study is registered with EudraCT.

Dexamethasone intravitreal implant in vitrectomized versus nonvitrectomized eyes for treatment of patients with persistent diabetic macular edema

PURPOSE

To compare the 6-month anatomic and best-corrected visual acuity (BCVA) response after sustained-release dexamethasone (DEX) intravitreal implant between nonvitrectomized and vitrectomized eyes with persistent diabetic macular edema (DME).

METHODS

Retrospective, comparative, and consecutive review of the medical records of 58 patients with decreased visual acuity, due to refractory DME, who underwent a single injection of Ozurdex between November 2010 and January 2012, at the Instituto de Microcirurgia Ocular, Barcelona, Spain. Then, we divided patients into 2 groups: 24 eyes who had undergone standard pars plana vitrectomy (vitrectomized group), and 34 eyes that were not operated on (nonvitrectomized group). Outcomes measured were BCVA and foveal thickness (FT) at baseline and at months 1, 3, and 6.

RESULTS

Twenty-four of 58 eyes had prior vitrectomy (41%). Statistically significant improvement in BCVA also was seen at 1 month after treatment with a DEX implant and at each subsequent follow-up visit, in either groups (P<0.05). All of the FT reduction outcomes were statistically significant in both groups, with respect to baseline data (P<0.05). There were no statistically significant differences in BCVA and FT between nonvitrectomized and vitrectomized eyes at any time point (P<0.05).

CONCLUSION

In this study, the clinical findings were similar between nonvitrectomized and vitrectomized eyes. Intravitreal treatment with a DEX implant safely reduced DME and improved visual acuity in both groups. No statistically significant differences were found between the 2 groups regarding FT and BCVA.

Profile of ocriplasmin and its potential in the treatment of vitreomacular adhesion

The recent approval by the US Food and Drug Administration of ocriplasmin for the treatment of symptomatic vitreomacular adhesion (VMA), often associated with vitreomacular traction (VMT) and macular hole (MH), has brought new attention to the field of pharmacologic vitreolysis. The need for an enzyme to split the vitreomacular interface, which is formed by a strong adhesive interaction between the posterior vitreous cortex and the internal limiting membrane, historically stems from pediatric eye surgery. This review summarizes the different anatomic classifications of posterior vitreous detachment or anomalous posterior vitreous detachment and puts these in the context of clinical pathologies commonly observed in clinical practice of the vitreoretinal specialist, such as MH, VMT, age-related macular degeneration, and diabetic macular edema. We revisit the outcome of the Phase II studies that indicated ocriplasmin was a safe and effective treatment for selected cases of symptomatic VMA and MH. Release of VMA at day 28 was achieved by 26.5% of patients in the ocriplasmin group versus 10.1% in the placebo group (P<0.001). Interestingly, for MHs, the numbers were more remarkable. Predictive factors for successful ocriplasmin treatment were identified for VMT (VMA diameter smaller than 1,500 μm) and MH (smaller than 250 μm). In comparison with the highly predictable outcome after vitrectomy, the general success rate of ocriplasmin not under clinical trial conditions has not fully met expectations and needs to be proven in real-world clinical settings. The ocriplasmin data will be compared in the future with observational data on spontaneous VMA release, will help retina specialists make more accurate predictions, and will improve outcome rates.

Intraocular surgery in a large diabetes patient population: risk factors and surgical results

The prevalence of diabetes is on the increase in developed countries. Accordingly, the prevention and treatment of vision-threatening diabetic eye complications is assuming greater importance. The overall aim of this thesis is to analyse risk factors for intraocular surgery in a large diabetes population and to report surgical results. The specific objectives are to (1) estimate the incidence of diabetic vitrectomy and analyse risk factors (Study I), (2) report long-term results, prognostic factors and incidence of cataract surgery after diabetic vitrectomy (Study II), (3) report results and prognostic factors after cataract surgery in diabetes patients (Study III) and (4) analyse risk factors for diabetic papillopathy with emphasis on metabolic control variability (Study IV). All studies are based on a close-to-complete national surgery register and a large, closely followed diabetic retinopathy screening population. Study I (cohort study, 3980 type 1 diabetes patients) illustrates that diabetic vitrectomy is rarely required in a diabetes patient population with varying degrees of diabetic retinopathy. The risk of reaching diabetic vitrectomy increases fourfold with poor metabolic control, defined as glycosylated haemoglobin A1c > 75 mmol/mol (~9%), which points to good metabolic control as an important preventive measure. Study II (cohort study, 167 diabetes patients) shows that most diabetic vitrectomy patients stand to gain visual acuity ≥0.3 after surgery. Visual acuity is stable after 1 year, and the stability is maintained through 10 years of follow-up. The use of silicone oil for endotamponade is a consistent long-term predictor of low vision after surgery. The risk of requiring cataract surgery after diabetic vitrectomy is substantial, and the risk increases if silicone oil is used. Study III (cohort study, 285 diabetes patients) shows, on the other hand, that diabetes patients can expect a significant improvement in visual acuity after cataract surgery, regardless of the degree of diabetic retinopathy. Poor preoperative visual acuity, a high degree of diabetic retinopathy and advanced age are predictors of a poor visual acuity after surgery. The risk of diabetic macular oedema after surgery is 4%. Finally, Study IV (case-control study, 2066 type 1 diabetes patients) demonstrates that diabetic papillopathy shares characteristics with diabetic retinopathy. The risk of experiencing diabetic papillopathy increases markedly with a drastic, recent reduction in glycosylated haemoglobin A1c and a small optic disc. This lends support to the theory that diabetic eye complications may occur in anatomically predisposed patients in response to metabolic control variability. Overall, results after intraocular surgery in diabetes patients are favourable. Surgery, however, is associated with costs to society, patient discomfort and risk of complications. This thesis provides an analysis of risk factors for intraocular surgery and identifies prognostic factors for visual acuity after surgery, which can be used for preventive purposes, surgical decision-making and patient counselling.

Vitreomacular adhesion and neovascular age-related macular degeneration

We explore the hypothesis that vitreomacular adhesion (VMA) and vitreomacular traction (VMT) play a role in the pathogenesis and clinical course of neovascular ("wet") age-related macular degeneration (AMD). Several biological theories are offered to explain this possible association, including direct tractional force, altered vitreous oxygenation, altered diffusion coefficients of intravitreal molecules, and alterations in the pharmacokinetics of intravitreal drugs. Release of VMT may improve the clinical course of neovascular AMD, and a few case series suggest that vitrectomy can lead to both a functional and anatomic improvement. A large, randomized, controlled clinical trial is underway, investigating pharmacologic release of VMA in eyes with neovascular AMD.

Current treatments in diabetic macular oedema: systematic review and meta-analysis

OBJECTIVES

The aim of this systematic review is to appraise the evidence for the use of anti-VEGF drugs and steroids in diabetic macular oedema (DMO) as assessed by change in best corrected visual acuity (BCVA), central macular thickness and adverse events

DATA SOURCE

MEDLINE, EMBASE, Web of Science with Conference Proceedings and the Cochrane Library (inception to July 2012). Certain conference abstracts and drug regulatory web sites were also searched.

STUDY ELIGIBILITY CRITERIA, PARTICIPANTS AND INTERVENTIONS

Randomised controlled trials were used to assess clinical effectiveness and observational trials were used for safety. Trials which assessed triamcinolone, dexamethasone, fluocinolone, bevacizumab, ranibizumab, pegaptanib or aflibercept in patients with DMO were included.

STUDY APPRAISAL AND SYNTHESIS METHODS

Risk of bias was assessed using the Cochrane risk of bias tool. Study results are narratively described and, where appropriate, data were pooled using random effects meta-analysis.

RESULTS

Anti-VEGF drugs are effective compared to both laser and placebo and seem to be more effective than steroids in improving BCVA. They have been shown to be safe in the short term but require frequent injections. Studies assessing steroids (triamcinolone, dexamethasone and fluocinolone) have reported mixed results when compared with laser or placebo. Steroids have been associated with increased incidence of cataracts and intraocular pressure rise but require fewer injections, especially when steroid implants are used.

LIMITATIONS

The quality of included studies varied considerably. Five of 14 meta-analyses had moderate or high statistical heterogeneity.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

The anti-VEGFs ranibizumab and bevacizumab have consistently shown good clinical effectiveness without major unwanted side effects. Steroid results have been mixed and are usually associated with cataract formation and  intraocular pressure increase. Despite the current wider spectrum of treatments for DMO, only a small proportion of patients recover good vision (≥20/40), and thus the search for new therapies needs to continue.

Pathophysiology and treatment of diabetic retinopathy

In the past years, the management of diabetic retinopathy (DR) relied primarily on a good systemic control of diabetes mellitus, and as soon as the severity of the vascular lesions required further treatment, laser photocoagulation or vitreoretinal surgery was done to the patient. Currently, even if the intensive metabolic control is still mandatory, a variety of different clinical strategies could be offered to the patient. The recent advances in understanding the complex pathophysiology of DR allowed the physician to identify many cell types involved in the pathogenesis of DR and thus to develop new treatment approaches. Vasoactive and proinflammatory molecules, such as vascular endothelial growth factor (VEGF), play a key role in this multifactorial disease. Current properly designed trials, evaluating agents targeting VEGF or other mediators, showed benefits in the management of DR, especially when metabolic control is lacking. Other agents, directing to the processes of vasopermeability and angiogenesis, are under investigations, giving more hope in the future management of this still sight-threatening disease.

Diabetic macular edema: new trends in management

The treatment of diabetic macular edema may be evolving from a laser ablative approach into a pharmacotherapeutic approach. The exponential growth that has occurred over the past decade in the retinal pharmacotherapy field has led to the development of several pharmacotherapies for retinal vascular diseases such as diabetic macular edema. Many of these agents, in the form of intravitreal injections or sustained delivery devices, have already undergone clinical trial testing for safety and efficacy and many others are currently being similarly evaluated. Some of these agents have proven to be more efficacious than traditional laser therapy, and it is possible that traditional laser therapy for diabetic macular edema may be abandoned altogether in the near future, especially with the introduction of the micropulse laser. However, more research and experience is still needed in order to determine the best treatment agent or combination of therapeutic modalities, as well as the best treatment regimen for a given patient. In this article, we briefly review the major new developments in the field of diabetic macular edema treatment. In addition, we touch on some of the promising forthcoming therapies.

Factors associated with visual acuity outcomes after vitrectomy for diabetic macular edema: diabetic retinopathy clinical research network

PURPOSE

To evaluate factors ¶associated with favorable outcomes after vitrectomy for diabetic macular edema.

METHODS

Data were collected prospectively on 241 eyes undergoing vitrectomy for diabetic macular edema. Multivariate models were used to evaluate associations of 20 preoperative and intraoperative factors with 6-month outcomes of visual acuity and retinal thickness.

RESULTS

Median central subfield thickness decreased from 412 μm to 278 μm at 6 months, but median visual acuity remained unchanged (20/80, Snellen equivalent). Greater visual acuity improvement occurred in eyes with worse baseline acuity (P < 0.001) and in eyes in which an epiretinal membrane was removed (P = 0.006). Greater reduction in central subfield thickness occurred with worse baseline visual acuity (P < 0.001), greater preoperative retinal thickness (P = 0.001), removal of internal limiting membrane (P = 0.003), and optical coherence tomography evidence of vitreoretinal abnormalities (P = 0.006). No associations with clinician's preoperative assessments of the posterior vitreous were identified.

CONCLUSION

These results suggest that the removal of epiretinal membranes may favorably affect visual outcome after vitrectomy. Preoperative presence of vitreoretinal abnormalities appeared to be associated with somewhat greater reductions in retinal thickness but not with visual acuity outcome. These results may be useful for future studies evaluating vitrectomy for diabetic macular edema.

Reduced concentrations of angiogenesis-related factors in vitreous after vitrectomy in patients with proliferative diabetic retinopathy

BACKGROUND

The purpose of this study was to determine whether vitrectomy alters the angiogenic profile in the vitreous of eyes with proliferative diabetic retinopathy (PDR).

METHODS

We measured the levels of angiopoietin-2, HGF, bFGF, PDGF, TIMP-1, and TIMP-2 by sandwich enzyme linked immunosorbent assay (ELISA) in vitreous samples from 27 eyes of 26 patients with PDR before pars plana vitrectomy (without IOL implantation) and in 12 fluid samples from 12 patients with PDR obtained during an IOL implantation 3.5 to 9 (mean 4.9) months after an earlier vitrectomy. The levels of these factors were also measured in 12 vitreous samples obtained from 12 eyes that had undergone epiretinal membrane (ERM) or macular hole (MH) surgeries.

RESULTS

The mean vitreous levels of both angiopietin-2 (103 pg/ml) and HGF (1091 pg/ml) in the sample from eyes with PDR collected at the time of the IOL implantation were significantly lower than in those collected before the vitrectomy (P < 0.01). On the other hand, the changes in the levels of TIMP-1 and TIMP-2 were both not significant after vitrectomy.

CONCLUSION

The significant decrease of angiopietin-2 and HGF in the vitreous fluid after vitrectomy suggests that vitrectomy shifts the eye towards an anti-angiogenic environment.