Intravitreal diclofenac versus intravitreal triamcinolone acetonide in the treatment of diabetic macular edema

Neuroinflammation and neurodegeneration in diabetic retinopathy

Diabetic retinopathy (DR) is the most common complication of diabetes and has been historically regarded as a microangiopathic disease. Now, the paradigm is shifting toward a more comprehensive view of diabetic retinal disease (DRD) as a tissue-specific neurovascular complication, in which persistently high glycemia causes not only microvascular damage and ischemia but also intraretinal inflammation and neuronal degeneration. Despite the increasing knowledge on the pathogenic pathways involved in DR, currently approved treatments are focused only on its late-stage vasculopathic complications, and a single molecular target, vascular endothelial growth factor (VEGF), has been extensively studied, leading to drug development and approval. In this review, we discuss the state of the art of research on neuroinflammation and neurodegeneration in diabetes, with a focus on pathophysiological studies on human subjects, in vivo imaging biomarkers, and clinical trials on novel therapeutic options.

Nonsteroidal anti-inflammatory drugs for retinal neurodegenerative diseases

Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most common prescription drugs for inflammation, and topical NSAIDs are often used in ophthalmology to reduce pain, photophobia, inflammation, and edema. In recent years, many published reports have found that NSAIDs play an important role in the treatment of retinal neurodegenerative diseases, such as age-related macular degeneration (AMD), diabetic retinopathy (DR), glaucoma, pathological myopia, and retinitis pigmentosa (RP). The aim of the current review is to provide an overview of the role of various NSAIDs in the treatment of retinal neurodegenerative diseases and the corresponding mechanisms of action. This review highlighted that the topical application of NSAIDs for the treatment of retinal degenerative diseases has been studied to a remarkable extent and that its beneficial effects in many diseases have been proven. In the future, prospective studies with large study populations are required to extend these effects to clinical settings.

Intravitreal steroids for macular edema in diabetes

BACKGROUND

Diabetic macular edema (DME) is secondary to leakage from diseased retinal capillaries with thickening of central retina, and is an important cause of poor central visual acuity in people with diabetic retinopathy. Intravitreal steroids have been used to reduce retinal thickness and improve vision in people with DME.

OBJECTIVES

To assess the effectiveness and safety of intravitreal steroid therapy compared with other treatments for DME.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase on 15 May, 2019. We also searched reference lists, Science Citation Index, conference proceedings, and relevant trial registers. We conducted a top up search on 21 October, 2020.

SELECTION CRITERIA

We included randomized controlled trials that evaluated any type of intravitreal steroids as monotherapy against any other intervention (e.g. observation, laser photocoagulation, anti-vascular endothelial growth factor (antiVEGF) for DME.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility and risk of bias and extracted data. Where appropriate, we performed meta-analyses.

MAIN RESULTS

We included 10 trials (4348 participants, 4505 eyes). These trials compared intravitreal steroid therapies versus other treatments, including intravitreal antiVEGF therapy, laser photocoagulation, and sham injection. Most trials had an overall unclear or high risk of bias. One trial (701 eyes ) compared intravitreal dexamethasone implant 0.7mg with sham. We found moderate-certainty evidence that dexamethasone leads to slightly more improvement of visual acuity than sham at 12 months (mean difference [MD] -0.08 logMAR, 95% confidence interval [CI] -0.12 to -0.05 logMAR). Regarding improvement of three or more lines of visual acuity, there was moderate-certainty evidence in favor of dexamethasone at 12 months, but the CI covered the null value (risk ratio (RR) 1.39, 95% CI 0.91 to 2.12). Regarding adverse events, dexamethasone increased by about four times the risk of cataract progression and the risk of using intraocular pressure (IOP)-lowering medications compared to sham (RR 3.89, 95% CI 2.75 to 5.50 and RR 4.54, 95% CI 3.19 to 6.46, respectively; moderate-certainty evidence); about 4 in 10 participants treated with dexamethasone needed IOP-lowering medications. Two trials (451 eyes) compared intravitreal dexamethasone implant 0.7mg with intravitreal antiVEGF (bevacizumab and ranibizumab). There was moderate-certainty evidence that visual acuity improved slightly less with dexamethasone compared with antiVEGF at 12 months (MD 0.07 logMAR, 95% CI 0.04 to 0.09 logMAR; 2 trials; 451 participants/eyes; I² = 0%). The RR of gain of three or more lines of visual acuity was inconsistent between trials, with one trial finding no evidence of a difference between dexamethasone and bevacizumab at 12 months (RR 0.99, 95% CI 0.70 to 1.40; 1 trial; 88 eyes), and the other, larger trial finding the chances of vision gain were half with dexamethasone compared with ranibizumab (RR 0.50, 95% CI 0.32 to 0.79; 1 trial; 432 participants). The certainty of evidence was low. Cataract progression and the need for IOP-lowering medications increased more than 4 times with dexamethasone implant compared to antiVEGF (moderate-certainty evidence). One trial (560 eyes) compared intravitreal fluocinolone implant 0.19mg with sham. There was moderate-certainty evidence that visual acuity improved slightly more with fluocinolone at 12 months (MD -0.04 logMAR, 95% CI -0.06 to -0.01 logMAR). There was moderate-certainty evidence that an improvement in visual acuity of three or more lines was more common with fluocinolone than with sham at 12 months (RR 1.79, 95% CI 1.16 to 2.78). Fluocinolone also increased the risk of cataract progression (RR 1.63, 95% CI 1.35 to 1.97; participants = 335; moderate-certainty evidence), which occurred in about 8 in 10 participants, and the use of IOP-lowering medications (RR 2.72, 95% CI 1.87 to 3.98; participants = 558; moderate-certainty evidence), which were needed in 2 to 3 out of 10 participants. One small trial with 43 participants (69 eyes) compared intravitreal triamcinolone acetonide injection 4 mg with sham. There may be a benefit in visual acuity at 24 months (MD -0.11 logMAR, 95% CI -0.20 to -0.03 logMAR), but the certainty of evidence is low. Differences in adverse effects were poorly reported in this trial. Two trials (615 eyes) compared intravitreal triamcinolone acetonide injection 4mg with laser photocoagulation and reached discordant results. The smaller trial (31 eyes followed up to 9 months) found more visual acuity improvement with triamcinolone (MD -0.18 logMAR, 95% CI -0.29 to -0.07 logMAR), but a larger, multicenter trial (584 eyes, 12-month follow-up) found no evidence of a difference regarding change in visual acuity (MD 0.02 logMAR, 95% CI -0.03 to 0.07 logMAR) or gain of three or more lines of visual acuity (RR 0.85, 95% CI 0.55 to 1.30) (overall low-certainty evidence). Cataract progression was about three times more likely (RR 2.68, 95% CI 2.21 to 3.24; moderate-certainty evidence) and the use of IOP-lowering medications was about four times more likely (RR 3.92, 95% CI 2.59 to 5.96; participants = 627; studies = 2; I² = 0%; moderate-certainty evidence) with triamcinolone. About 1 in 3 participants needed IOP-lowering medication. One small trial (30 eyes) compared intravitreal triamcinolone acetonide injection 4mg with intravitreal antiVEGF (bevacizumab or ranibizumab). Visual acuity may be worse with triamcinolone at 12 months (MD 0.18 logMAR, 95% CI 0.10 to 0.26 logMAR); the certainty of evidence is low. Adverse effects were poorly reported in this trial. Four trials reported data on pseudophakic participants, for whom cataract is not a concern. These trials found no decrease in visual acuity in the second treatment year due to cataract progression.

AUTHORS' CONCLUSIONS

Intravitreal steroids may improve vision in people with DME compared to sham or control. Effects were small, about one line of vision or less in most comparisons. More evidence is available for dexamethasone or fluocinolone implants when compared to sham, and the evidence is limited and inconsistent for the comparison of dexamethasone with antiVEGF treatment. Any benefits should be weighed against IOP elevation, the use of IOP-lowering medication and, in phakic patients, the progression of cataract. The need for glaucoma surgery is also increased, but remains rare.

Intravitreal bromfenac liposomal suspension (100 μg / 0.1 ml). A safety study in rabbit eyes

INTRODUCTION

There is a need to find alternative treatments for MEe. Bromfenac has shown promise in inhibiting the COX-2 enzymatic pathway that partially causes the inflammatory cascade which contributes to the precipitation of ME. However, like other NSAID's, its intraocular half-life is limited. We hypothesize that a delayed-release liposome formulation containing bromfenac might provide a similar anti-inflammatory effect as long-lasting steroid release systems without the well-known steroidal side-effects. We introduced a novel formulation with these characteristics into the vitreous cavity of rabbit eyes in order to evaluate its safety profile.

MATERIAL AND METHODS

10 left eyes of rabbits were injected with the liposome-encapsulated bromfenac suspension (100 μg/0.1 ml). Basal ERG's were recorded. Total follow-up time was 3 months, at which point ERG's were repeated and eyes were enucleated for histopathological study. Total amplitude and implicit times were recorded. A difference of 25% in either recording was considered significant. Significance was assessed using the paired-t test and Wilcoxon matched-pairs signed-rank test. A p-value of <0.05 was considered significant.

RESULTS

No significant changes were recorded in ERG measurements after 3 months when compared to basal measurements. Histopathological analysis of retinal specimens found no traces of liposome-induced toxicity.

CONCLUSION

The liposome-encapsulated bromfenac suspension (100 μg/0.1 ml) is not toxic and has been proven safe to use in an animal model. Therefore, this formulation shows promise as a possible future alternative treatment for ME and should be further studied to show its biological effect and efficacy.

The Evolving Treatment of Diabetic Retinopathy

Purpose

To review the current therapeutic options for the management of diabetic retinopathy (DR) and diabetic macular edema (DME) and examine the evidence for integration of laser and pharmacotherapy.

Methods

A review of the PubMed database was performed using the search terms diabetic retinopathy, diabetic macular edema, neovascularization, laser photocoagulation, intravitreal injection, vascular endothelial growth factor (VEGF), vitrectomy, pars plana vitreous surgery, antiangiogenic therapy. With additional cross-referencing, this yielded 835 publications of which 301 were selected based on content and relevance.

Results

Many recent studies have evaluated the pharmacological, laser and surgical therapeutic strategies for the treatment and prevention of DR and DME. Several newer diagnostic systems such as optical coherence tomography (OCT), microperimetry, and multifocal electroretinography (mfERG) are also assisting in further refinements in the staging and classification of DR and DME. Pharmacological therapies for both DR and DME include both systemic and ocular agents. Systemic agents that promote intensive glycemic control, control of dyslipidemia and antagonists of the renin-angiotensin system demonstrate beneficial effects for both DR and DME. Ocular therapies include anti-VEGF agents, corticosteroids and nonsteroidal anti-inflammatory drugs. Laser therapy, both as panretinal and focal or grid applications continue to be employed in management of DR and DME. Refinements in laser devices have yielded more tissue-sparing (subthreshold) modes in which many of the benefits of conventional continuous wave (CW) lasers can be obtained without the adverse side effects. Recent attempts to lessen the burden of anti-VEGF injections by integrating laser therapy have met with mixed results. Increasingly, vitreoretinal surgical techniques are employed for less advanced stages of DR and DME. The development and use of smaller gauge instrumentation and advanced anesthesia agents have been associated with a trend toward earlier surgical intervention for diabetic retinopathy. Several novel drug delivery strategies are currently being examined with the goal of decreasing the therapeutic burden of monthly intravitreal injections. These fall into one of the five categories: non-biodegradable polymeric drug delivery systems, biodegradable polymeric drug delivery systems, nanoparticle-based drug delivery systems, ocular injection devices and with sustained release refillable devices. At present, there remains no one single strategy for the management of the particular stages of DR and DME as there are many options that have not been rigorously tested through large, randomized, controlled clinical trials.

Conclusion

Pharmacotherapy, both ocular and systemic, will be the primary mode of intervention in the management of DR and DME in many cases when cost and treatment burden are less constrained. Conventional laser therapy has become a secondary intervention in these instances, but remains a first-line option when cost and treatment burden are more constrained. Results with subthreshold laser appear promising but will require more rigorous study to establish its role as adjunctive therapy. Evidence to support an optimal integration of the various treatment options is lacking. Central to the widespread adoption of any therapeutic regimen for DR and DME is substantiation of safety, efficacy, and cost-effectiveness by a body of sound clinical trials.

Predictor of Early Remission of Diabetic Macular Edema under As-Needed Intravitreal Ranibizumab

The early remission of diabetic macular edema (DME) often occurs in eyes treated with anti-vascular endothelial growth factor (VEGF) treatment. We retrospectively reviewed and characterized eyes with early remission of DME at six months in 80 eyes under pro re nata (PRN) intravitreal ranibizumab (IVR) injections. The number of eyes without center-involved DME gradually increased and 14 and 20 eyes achieved remission of DME at 3 or 6 months, respectively, under the PRN regimen following three monthly loading doses. In particular, eyes with early remission at 6 months had smaller CSF thickness than those without the remission before and after the treatment except at the 1-month visit (P < 0.05); however, the changes in CSF thickness did not differ between them. VA and its changes were not different between eyes with and without remission. Multivariate analysis revealed that smaller CSF thickness at baseline predicted the early remission of DME under PRN IVR injections (odds ratio, 0.989; 95% confidence interval, 0.982–0.997; P = 0.008). These data elucidate the clinical characteristics of early remission of DME under PRN IVR injections and suggest that smaller CSF thickness at baseline is a novel predictor of early remission under PRN IVR injections for DME.

Intravitreal diclofenac versus intravitreal bevacizumab in persistent diabetic macular edema: Anatomical and functional outcome

PURPOSE

To compare the efficacy of diclofenac versus bevacizumab following single intravitreal injection in eyes with persistent diabetic macular edema.

METHODS

Fifty eyes with persistent DME were randomly allocated to intravitreal injection of 500 µg/0.1 ml of diclofenac (N = 20) or 1.25 mg/0.05 mL of bevacizumab (N = 20) or to non-treatment (10 eyes). Preoperative and postoperative visual acuity, central, paracentral macular thickness and intraocular pressure (IOP) were recorded and compared between the three groups up to 4 weeks.

RESULTS

Diclofenac and bevacizumab groups showed statistically significant reduction in central and paracentral macular thickness (diclofenac: p = 0.006, 0.02 and bevacizumab: p = 0.02, 0.01), without statistically significant difference between the two groups. The two groups showed no statistically significant difference in mean visual acuity or mean line improvement. Mean visual acuity improvement didn't reach statistical significance in either group. Diclofenac group showed statistically significant reduced IOP (P = 0.02). Control eyes did not show any change in mean visual acuity, macular thickness or IOP.

CONCLUSION

In persistent DME, diclofenac has a structural effect comparable to bevacizumab on central macular thickness. However, significant functional gain may not be accomplished by single injection. Unlike naïve DME, persistent cases may be confounded by systemic and local factors necessitating repeated injection of diclofenac.

Intravitreal diclofenac for treatment of refractory uveitis-associated cystoid macular oedema: A before and after clinical study

BACKGROUND

Cystoid macular oedema (CME) is one of the important complications of uveitis leading to irreversible blindness. Currently, there is no gold standard treatment for this condition. The aim of this study was to investigate the effects of single intravitreal diclofenac (IVD) injection on short-term outcome of refractory uveitis-associated CME.

METHODS

This was a prospective clinical study on 16 consecutive patients (16 eyes) with refractory uveitis-associated CME. Intravitreal injection of 500 μg/0.1 ml of diclofenac sodium was given to the patients. The clinical outcomes considered were best-corrected visual acuity (BCVA) change and central macular thickness (CMT) changes in the pre- and postinjection periods. Follow-up examinations were performed at 1 and 4 weeks after the injection.

RESULTS

Age of the patients varied from 18 to 59 years (mean ± SD: 39.5 ± 13.2 years). Ten patients (62.5%) were females. Statistically significant differences were found in the decrease of mean BCVA (logMAR) (p = 0.043) and mean CMT (p = 0.003) during the study period. There was no significant difference in the intraocular pressure (IOP) increase at the end of the study (p = 0.94).

CONCLUSION

Intravitreal diclofenac (IVD) may be a promising treatment for refractory uveitis-associated CME. Further clinical trials with a larger sample size should be conducted to confirm these findings and compare them with other treatments.

Impact of topical nonsteroidal anti-inflammatory drugs in prevention of macular edema following cataract surgery in diabetic patients

AIM

To evaluate the efficacy of prophylactic administration of topical non-steroidal anti-inflammatory drugs (NSAIDs) on macular edema following cataract surgery in diabetic patients, and to compare between types of NSAIDs (ketorolac tromethamine 0.4% and nepafenac 0.1%).

METHODS

Group 1 (control) received artificial tears substitute as a placebo group, group 2 (nepafenac) received topical nepafenac 0.1%, and group 3 (ketorolac) received topical ketorolac tromethamine 0.4%. Patients were examined postoperatively after completing one week, one month, two months and three months' intervals for evaluating cystoid macular edema (CME) development. The main study outcomes were achieving the best corrected visual acuity (BCVA) and change in the central macular thickness (CMT) measured with optical coherence topography (OCT).

RESULTS

Eighty eyes of 76 patients were included in this study. BCVA showed a statistically significant difference at the third month postoperative follow up between the control group and the NSAIDs groups (P=0.04). There was an increase in the CMT in all cases starting from postoperative first week until third month. CMT showed a statistically significant difference between control group and NSAIDs groups from postoperative first month until third month (P=0.008, 0.027, 0.004). There was no statistically significant difference between nepafenac and ketorolac groups in BCVA and OCT CMT.

CONCLUSION

Prophylactic preoperative and postoperative NSAIDs may have a role in reducing the frequency and severity of CME in diabetic eyes following cataract surgery.

Efficacy of systemic diclofenac sodium on intravitreal concentration

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs), as an alternative, are replacing corticosteroids in ocular inflammatory diseases. Diclofenac has been used mainly topically, and recent focus has been on intravitreal delivery. Both of these methods have been shown to have complications in long-term application.

PURPOSE

To assess the efficacy of slow release oral diclofenac sodium on intravitreal concentration in experimental model of chemically injured eyes.

METHODS

In an experimental double-masked clinical trial, right eyes of 24 albino rabbits were chemically injured by 1 N NaOH. One hour after chemical injury, 10 cc suspension gavage containing 100 mg slow release diclofenac sodium was administered in all cases. 2, 4, 6, 12, 24, 48 h after gavage, vitreous samples were obtained in all cases. Intravitreal concentration of diclofenac sodium was evaluated in all samples using high-performance liquid chromatography (HPLC) method.

RESULTS

Intravitreal diclofenac levels by oral intake were enhanced by the inflammation in all the measurements. In inflamed eyes, diclofenac concentration was ten times more than control eye (2.658 ± 0.344 vs. 0.242 ± 0.0279 and 1.617 ± 0.527 vs. 0.148 ± 0.095; in 2 and 4 h, respectively). After 6 h, diclofenac concentration was statistically different, although it reduced below 1 μg/ml.

CONCLUSION

Diclofenac is delivered to the inflamed eye more than healthy eye. It seems that by oral diclofenac consumption, it is possible to make a significant intravitreal concentration.

UNREPORTED SIDE EFFECT OF INTRAVITREAL DICLOFENAC IN CHRONIC DIABETIC MACULAR EDEMA

PURPOSE

To evaluate the safety and efficacy of intravitreal diclofenac sodium.

METHODS

A 61-year-old male with persistent diabetic macular edema was treated with 450 μg of intravitreal diclofenac sodium (systemic preparation).

RESULTS

Postinjection Day 1, the spectral domain optical coherence tomography showed irregular vitreoretinal interface with wrinkling and separation of the internal limiting membrane from the nerve fiber layer with homogeneity of the inner layers. At 1 month, the compactness of the retinal layers was restored. Complete resolution of the cystoid macular edema was seen. At 1 year, there was mild flattening of the foveal depression with epiretinal membrane.

CONCLUSION

Various studies have shown the safety and efficacy of intravitreal diclofenac without any reported side effect. We report the inner retinal toxicity in the form of cystic spaces and splitting of internal limiting membrane from nerve fiber layer on the first follow-up day, postinjection, which resolved over a period of 1 month. Further studies are needed to assess the safety of intravitreal diclofenac sodium.

Intravitreal Diclofenac in the Treatment of Macular Edema Due to Branch Retinal Vein Occlusion

BACKGROUND AND OBJECTIVE

To evaluate the effect of a single dose of intravitreal diclofenac on macular edema (ME) due to branch retinal vein occlusion (BRVO).

PATIENTS AND METHODS

In this prospective, interventional case series, 15 eyes with BRVO and ME with central macular thickness (CMT) greater than 250 µm on spectral-domain optical coherence tomography (SD-OCT) were enrolled. All patients were given 0.05 mg/0.1 mL of intravitreal diclofenac under aseptic conditions and followed up for 3 months with respect to best-corrected visual acuity (BCVA), intraocular pressure (IOP), fundus fluorescein angiography, and CMT measured on OCT.

RESULTS

The mean visual acuity improved from 0.115 ± 0.03 preoperatively to 0.356 ± 0.29 at 3 months (P = .002). Mean line improvement was 2.2 ± 1.6. Mean preoperative CMT decreased from 453.2 µm ± 55.3 µm to 340.47 µm ± 101 µm at 3 months postoperatively (P = .001). The mean preoperative IOP was 16.4 mm Hg ± 1.59 mm Hg, whereas the mean postoperative IOP was 16.6 mm Hg ± 1.58 mm Hg (P = .08). None of the 12 phakic eyes showed evidence of cataract progression.

CONCLUSION

Intravitreal diclofenac is safe and effective in improving BCVA and decreasing CMT in patients with BRVO and ME.

Intravitreal Diclofenac plus Bevacizumab versus Bevacizumab alone in treatment-naive diabetic macular edema: a randomized double-blind clinical trial

The aim of this study is to evaluate the short-term effects of a single intravitreal injection of 1.25 mg Bevacizumab combined with 300 lg/0.1 mL Diclofenac (IVB/D) versus 1.25 mg intravitreal Bevacizumab (IVB) alone in the treatment of naive diabetic macular edema (DME). In this prospective, randomized clinical trial, 80 eyes were included in the final analysis; 42 and 38 of which in the IVB and IVB/D groups, respectively. The primary outcome measure was a change in best-corrected visual acuity (BCVA) in logMAR at week 4. The secondary outcomes included changes in central macular thickness (CMT), macular volume, and potential injection-related complications. Significant improvement of BCVA was demonstrated in both study arms (mean reductions in LogMAR: -0.088 ± 0.278, -0.228 ± 0.330 for IVB and IVB/D, respectively). The difference in BCVA changes was in favor of IVB/D; however, not to a statistically significant level (P = 0.160). Significant reduction of CMT was documented in both study arms (mean reductions: 82.43 ± 160.09 and 153.26 ± 163.85 for IVB and IVB + IVD, respectively). Comparison of CMT changes between groups showed that IVB/D reduced CMT more than that of IVB (P = 0.04). Effects on macular volume corresponded to those of CMT. No injection-related complications or significant alterations in intraocular pressure were observed in any of the study arms. In treatment-naive DME, superiority of IVB/D combination therapy over IVB monotherapy may exist; especially as regards anatomical features. In our therapeutic arsenal for DME, IVD can be added as an adjunct to Bevacizumab.

Intravitreal ketorolac for the treatment of chronic cystoid macular edema after cataract surgery

Purpose

To report two cases of chronic postoperative cystoid macular edema, resistant to topical therapy, treated with consecutive intravitreal injections of ketorolac tromethamine.

Methods

Four daily intravitreal injections of 500 μg/0.05 mL of ketorolac were given to each patient. Complete clinical examination and OCT were performed before every injection, 1, 2, 3 weeks, and 1, 3, and 6 months after the last injection. Fluorescein angiography was performed at baseline examination, 1, 3, and 6 months after the last injection.

Results

In both cases, the edema regressed and visual acuity increased. At 6 months after the last injection, the leakage was significantly reduced at the fluorescein angiography.

Discussion

Both cases responded favorably to the consecutive intravitreal administration of ketorolac tromethamine. The long-lasting remission of the macular edema in these chronic cases underlines the therapeutic potential of these agents when delivered intravitreally.

Efficacy and vitreous levels of topical NSAIDs

INTRODUCTION

Nonsteroidal anti-inflammatory drugs (NSAIDs) are one of the most commonly prescribed medications and are routinely used for their analgesic, antipyretic, and anti-inflammatory properties. Because of their potent cyclooxygenase-inhibitory activity, they can inhibit pro-inflammatory prostaglandin synthesis, leading to complex inflammatory cascades. NSAIDs have been broadly used systemically for many decades and have recently become commercially available in the form of topical ophthalmic formulations. NSAIDs are weak acids with pKa values mostly between 3.5 and 4.5 and are poorly water-soluble. New, aqueous ophthalmic solutions of NSAIDs that afford better tissue penetration have recently been developed. In ophthalmological practice, topical NSAIDs are mostly used to stabilize pupillary dilation during intraocular surgery, manage postoperative pain and inflammation, and treat pseudophakic cystoid macular edema.

AREAS COVERED

This review focuses on the vitreous penetration of topical NSAIDs and their potential clinical applications in the treatment of retinal diseases.

EXPERT OPINION

A growing body of evidence suggests that NSAIDs may be beneficial in the treatment of age-related macular degeneration, diabetic retinopathy, and ocular tumors. Recent studies from our group and other authors have shown that the vitreous levels of NSAID exceed the median inhibitory concentration, which can significantly decrease vitreous PGE2 levels.

Updates in the management of diabetic macular edema

Diabetes mellitus is a chronic disease which has multiple effects on different end-organs, including the retina. In this paper, we discuss updates on diabetic macular edema (DME) and the management options. The underlying pathology of DME is the leakage of exudates from retinal microaneurysms, which trigger subsequent inflammatory reactions. Both clinical and imaging techniques are useful in diagnosing, classifying, and gauging the severity of DME. We performed a comprehensive literature search using the keywords "diabetes," "macula edema," "epidemiology," "pathogenesis," "optical coherence tomography," "intravitreal injections," "systemic treatment," "hypertension," "hyperlipidemia," "anemia," and "renal disease" and collated a total of 47 relevant articles published in English language. The main modalities of treatment currently in use comprise laser photocoagulation, intravitreal pharmacological and selected systemic pharmacological options. In addition, we mention some novel therapies that show promise in treating DME. We also review systemic factors associated with exacerbation or improvement in DME.

Sustained release of triamcinolone acetonide from an episcleral plaque of multilayered poly-ε-caprolactone matrix

A subtenon injection of triamcinolone acetonide (TA) is a widely used treatment modality for various chorio-retinal diseases. Although it is less invasive than intravitreal injection, it can produce dose-associated ocular complications and has the disadvantages associated with systemic TA exposure. In this study we have developed and evaluated an episcleral film consisting of TA and poly-ε-caprolactone (PCL). The films were prepared by spraying a mixture of PCL in dichloromethane and TA in acetone. The films were produced as 6mm wide and 12 mm long episcleral plaques. X-ray diffraction demonstrated an even distribution of TA crystals in PCL, although the TA was less crystalized than a native TA control. Fourier transform infrared spectroscopy revealed effective integration of TA within the PCL matrix. An in vitro study of the release of TA from the episcleral plaques showed that TA release rate was only 40-50% that of the equivalent native TA control. An in vivo study demonstrated that the plaques were well tolerated in rabbit eyes with significantly less systemic TA exposure. The episcleral plaques provided therapeutic vitreous TA levels for 3 months, while TA levels in the vitreous were detectable for only 1 month following an equivalent dose by subtenon TA injection. The PCL-TA 30-60 episcleral plaque may be further developed as a better alternative treatment for many chronic vitreo-retinal diseases, providing longer and controlled release and fewer drug-associated complications than those associated with a conventional subtenon injection of TA.

A pilot study of intravitreal diclofenac versus intravitreal triamcinolone for uveitic cystoid macular edema

PURPOSE

To compare the effect of intravitreal diclofenac (IVD) versus intravitreal triamcinolone (IVT) on refractory uveitic cystoid macular edema (CME).

METHODS

In this pilot randomized clinical trial, 15 eyes were randomly assigned to an IVD group, patients (8 eyes) who received a single intravitreal injection of diclofenac (500 μg/0.1 mL), and an IVT group (7 eyes), cases who received a single intravitreal injection of triamcinolone (2 mg). Change in best-corrected VA in logMAR at week 36 was the primary outcome measure. Secondary outcomes included changes in best-corrected visual acuity (BCVA) at 12 and 24 weeks, central macular thickness (CMT), macular leakage, and potential injection-related complications.

RESULTS

In the IVD group, BCVA was more than the baseline values in 4 eyes at 36 weeks; however, within-group analysis disclosed no statistically significant changes in the mean BCVA in this group. Nonetheless, in the IVT group, mean BCVA improved significantly at 12, 24, and 36 weeks compared to the baseline values. It was 0.86 ± 0.37 at baseline and 0.63 ± 0.48, 0.62 ± 0.42, and 0.43 ± 0.49 logMAR at 12, 24, and 36 weeks, respectively. Mean CMT reduction diminished also significantly only in the IVT group. Nevertheless, comparing the mean BCVA and CMT changes, macular leakage, and the occurrence of any injection-related complications, no significant difference was observed between the groups at any of the follow-up visits.

CONCLUSION

This pilot study demonstrated the superiority of IVT over IVD in the treatment of refractory uveitic CME regarding both functional and anatomical outcomes. Further studies are warranted to confirm potential benefit of IVD observed in this study.

Topical nonsteroidal anti-inflammatory drugs for macular edema

Nonsteroidal anti-inflammatory drugs (NSAIDs) are nowadays widely used in ophthalmology to reduce eye inflammation, pain, and cystoid macular edema associated with cataract surgery. Recently, new topical NSAIDs have been approved for topical ophthalmic use, allowing for greater drug penetration into the vitreous. Hence, new therapeutic effects can be achieved, such as reduction of exudation secondary to age-related macular degeneration or diabetic maculopathy. We provide an updated review on the clinical use of NSAIDs for retinal diseases, with a focus on the potential future applications.

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.

Nonsteroidal anti-inflammatory drugs for retinal disease

Nonsteroidal anti-inflammatory drugs (NSAIDs) are used extensively in ophthalmology for pain and photophobia after photorefractive surgery and to reduce miosis, inflammation, and cystoid macular edema following cataract surgery. In recent years, the US Food and Drug Administration has approved new topical NSAIDs and previously approved NSAIDs have been reformulated. These changes may allow for greater drug penetration into the retina and thereby offer additional therapeutic advantages. For example, therapeutic effects on diabetic retinopathy and age-related macular degeneration may now be achievable. We provide an updated review on the scientific rationale and clinical use of NSAIDs for retinal disease.

Intravitreal autologous plasmin as a therapeutic modality for diffuse diabetic macular edema

OBJECTIVES

To evaluate the outcome of vitreolysis using intravitreal autologous plasmin (IAP) injection as a sole therapeutic modality for patients with diffuse diabetic macular edema in comparison to triamcinolone acetonide (TA).

PATIENTS AND METHODS

The study included 50 diabetic patients, 18 males and 32 females, with a mean age of 66.4 ± 7.8 years and a mean duration of diabetes of 14 ± 2.4 years. All patients underwent full ophthalmologic examination and were allocated randomly into two groups: the TA group received 4 mg TA and the IAP group received 0.2 mL freshly home-prepared autologous plasmin. Outcome measures included determination of central macular thickness (CMT), best-corrected visual acuity (BCVA), and intraocular pressure (IOP) at 1, 3, and 6 months.

RESULTS

Both TA and plasmin induced significant decrease of CMT compared to baseline thickness with nonsignificant difference between both groups. The extent of decrease of CMT reached a peak at 1 month after injection and then started to decline until the sixth month, but was significantly thinner when compared to baseline thickness. However, the extent of deterioration was less evident with plasmin as the difference between follow-up measures at 3 and 6 months were nonsignificant compared to the 1-month measure and to each other. BCVA was significantly improved compared to baseline BCVA with a nonsignificant difference between both groups at 1 and 3 months, but at 6 months, mean BCVA significantly deteriorated in TA group compared to that recorded at 3 months, but not in the IAP group. At 3 and 6 months after injection, IOP was significantly lower in both groups compared to IOP at 1 month despite being significantly higher in the TA group, but IOP was nonsignificantly lower in the IAP group compared to baseline. Moreover, mean IOP estimated at 3 and 6 months was significantly higher in the TA group compared to the IAP group.

CONCLUSION

Vitreolysis using IAP injection provided effective diminution of CMT with improvement of BCVA and this effect was longer lasting and safer than intravitreal injection of TA without concomitant increase of IOP.