Intravitreal triamcinolone injection for chronic diabetic macular oedema with severe hard exudates

The evolving therapeutic landscape of diabetic retinopathy

INTRODUCTION

Diabetic retinopathy (DR) is a leading cause of blindness worldwide. Recent decades have seen rapid progress in the management of diabetic eye disease, evolving from pituitary ablation to photocoagulation and intravitreal pharmacotherapy. The advent of effective intravitreal drugs inhibiting vascular endothelial growth factor (VEGF) marked a new era in DR therapy. Sustained innovation has since produced several promising biologics targeting angiogenesis, inflammation, oxidative stress, and neurodegeneration.

AREAS COVERED

This review surveys traditional, contemporary, and emerging therapeutics for DR, with an emphasis on anti-VEGF therapies, receptor tyrosine kinase inhibitors, angiopoietin-Tie2 pathway inhibitors, integrin pathway inhibitors, gene therapy 'biofactory' approaches, and novel systemic therapies. Some of these investigational therapies are being delivered intravitreally via sustained release technologies for extended durability. Other investigational agents are being delivered non-invasively via topical and systemic routes. These strategies hold promise for early and long-lasting treatment of DR.

EXPERT OPINION

The evolving therapeutic landscape of DR is rapidly expanding our toolkit for the effective and durable treatment of blinding eye disease. However, further research is required to validate the efficacy of novel therapeutics and characterize real world outcomes.

Vitrectomy with internal limiting membrane peeling versus nonsurgical treatment for diabetic macular edema with massive hard exudates

Purpose

To compare the anatomical and functional outcomes of severe diabetic macular edema (DME) with massive hard exudates managed by pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling or nonsurgical treatment.

Methods

We retrospectively reviewed 40 eyes with DME and massive hard exudates treated with either PPV with ILM peeling (vitrectomy group, 21 eyes) or nonsurgical treatment with anti-vascular endothelium growth factor (VEGF) and/or steroids (nonsurgical group, 19 eyes). Changes in best-corrected visual acuity (BCVA) and central retinal thickness (CRT) and resolution of macular hard exudates were compared between the two groups.

Results

After treatment, CRT decreased steadily in the vitrectomy group but fluctuated in the nonsurgical group. Compared with eyes in the nonsurgical group, eyes in the vitrectomy group had better visual improvement (P < 0.05 at 6 and 12 months and the final visit) and greater decrease in CRT (P < 0.05 at 3 and 6 months and the final visit) after adjustment for baseline BCVA. Hard exudates resolved more rapidly in the vitrectomy group than in the nonsurgical group, with 94.1% versus 47.4% eyes showing significant absorption after 6 months of the treatment (P = 0.003). In the vitrectomy group, 62% eyes did not require any further injections for treating DME after the operation.

Conclusions

PPV with ILM peeling resulted in rapid resolution of hard exudates with significant anatomical and functional improvement in DME with massive hard exudates.

Removal of foveal hard exudates by subretinal balanced salt solution injection using 38-gauge needle in diabetic patients

PURPOSE

To examine the anatomic and visual outcomes after removal of foveal hard exudates through a macular hole created by subretinal balanced salt solution (BSS) injection.

METHODS

This was a retrospective, consecutive, case series. Six patients (7 eyes) underwent vitrectomy with removal of foveal hard exudates. All patients were women and the mean age was 65 years (range from 55 to 71). All patients had a history of panretinal photocoagulation. Previous treatments included intravitreal anti-vascular endothelial growth factor injection in one eye and vitrectomy in both eyes of one patient. The geometric mean preoperative decimal visual acuity was 0.11 (range from 0.08 to 0.3). The mean postoperative follow-up period was 12 months (range from 6 to 19). The status of lens was two phakic and five pseudophakic. Surgical procedures included simultaneous cataract surgery if phakic, creation of posterior vitreous detachment if not present, internal limiting membrane (ILM) peeling and a gas or air tamponade. Manual subretinal BSS injection using 38-gauge needle was performed at ILM-peeled area. Removal of foveal hard exudates was conducted by the water flow through the macular hole created during subretinal BSS injection.

RESULTS

Foveal hard exudates decreased in all cases early after surgery. The geometric mean final decimal visual acuity was 0.31 (range from 0.1 to 0.9). Visual acuity improved more than 0.2 LogMAR units in six eyes and unchanged in one eye. There was no severe complication and recurrence of macular edema.

CONCLUSION

This procedure may be effective for foveal hard exudates in diabetic patients.

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.

Macular edema resolution assessment with implantable dexamethasone in diabetic retinopathy (MERIT): a pilot study

Purpose

This study aimed to evaluate the effect of dexamethasone implantation on the hard exudates (HEX) in patients with diabetic macular edema (DME).

Study design

This was a nonrandomized open-label single-center prospective trial.

Methods

This study included 15 eyes of 11 subjects with DME. Key inclusion criteria were naïve eyes with DME with HEX within 3 mm of fovea with center-involving DME; central macular thickness (CMT) >250 μm at baseline; best-corrected visual acuity (BCVA) between 20/400 and 20/40. Key exclusion criteria were previous intraocular surgery and history of panretinal photocoagulation (PRP) in past 4 months. The primary outcome measure was change in total HEX area at the macula (in mm²) measured by semiautomated algorithm. Secondary outcome measures were change in visual acuity, low-contrast visual acuity (LCVA), retinal sensitivity (RS) on macular microperimetry, and CMT.

Results

The total HEX area reduced from 1.5 mm² (±1.46 mm²) at baseline to 0.89 mm² (±1.062 mm²) at the final visit (p=0.185). The CMT improved significantly (p=0.03) from 488.67 μm (±240.66 μm) to 326.93 μm (±135.84 μm) at the final visit. Mean BCVA remained stable (p=0.95) (50.93±16.65 at baseline and 50.6±18.95 at final visit). The mean LCVA and RS showed insignificant improvement (p=0.31 and p=0.28, respectively).

Conclusion

Our pilot study demonstrated an improving trend in reduction of total HEX area and other anatomical outcomes, with limited functional outcomes. Larger randomized studies with a larger sample size with a control group are warranted to establish management protocols for DME with significant subfoveal HEX.

Follow-Up after Intravitreal Triamcinolone Acetonide for Diabetic Macular Edema

PURPOSE

To report on the follow-up of patients who received an intravitreal high-dosage injection of triamcinolone acetonide (IVTA) as treatment of diffuse diabetic macular edema.

METHODS

The clinical interventional case-series study included 109 eyes (90 patients) with diffuse diabetic macular edema who consecutively received an IVTA of about 20 mg. Mean follow-up was 11.2 +/- 6.2 months.

RESULTS

Visual acuity improved significantly (p<0.001) from 0.89 +/- 0.33 logMAR to a best minimum of 0.65 +/- 0.35 logMAR. An increase in best visual acuity by at least 1 Snellen line, 2 lines, and 3 lines was found in 91 (83%) eyes, 68 (62%) eyes, and 45 (41%) eyes, respectively. Differences in visual acuity between baseline and follow-up examinations were significant for measurements performed at 1 month (p<0.001), 2 months (p<0.001), 3 months (p<0.001), and at 6 months (p=0.001) after the injection. At 9 months after the injection, mean visual acuity regressed significantly so that visual acuity at 9 months (p=0.83) and at 12 months after the injection (p=0.58) compared with baseline values did not differ significantly. Forty-seven (43%) eyes developed a rise in intraocular pressure (pressure >21 mmHg) for 6 to 8 months after the injection. No other severe complications were detected.

CONCLUSIONS

The duration of a visual acuity increase and intraocular pressure rise after high-dosage IVTA in diffuse diabetic macular edema is about 6 to 8 months. Compared with data in the literature, the high-dosage IVTA may not have a markedly higher profile of side effects than low-dosage IVTA.

Quantitative evaluation of hard exudates in diabetic macular edema after short-term intravitreal triamcinolone, dexamethasone implant or bevacizumab injections

Background

To quantitatively compare short-term hard exudates (HEs) alteration in patients with diabetic macular edema (DME) after intravitreal triamcinolone, dexamethasone implant or bevacizumab injections.

Methods

This retrospective study enrolled DME eyes with HEs that underwent a single-dose intravitreal injection of triamcinolone (25 eyes), dexamethasone implant (20 eyes), or three monthly injections of bevacizumab (25 eyes) and completed at least three months of follow-up. All patients were examined before and after 1, 2 and 3 months of injections. Using color fundus photographs, the amount of HEs was quantified by two masked graders. The difference in HEs area between baseline and each follow-up visit was compared among the three groups.

Results

After three months, HEs area was reduced to 52.9 ± 4.21% (P < 0.001) in the triamcinolone group, 63.6 ± 6.08% (P = 0.002) in the dexamethasone implant group, and 85.2 ± 5.07% (P = 0.198) in the bevacizumab group. A significant reduction in HEs appeared at one month in the triamcinolone group (53.5 ± 4.91%, P < 0.001) and at two months in the dexamethasone implant group (70.1 ± 5.21%, P = 0.039).

Conclusions

Our study suggests intravitreal steroids (triamcinolone, dexamethasone implants) significantly reduce HEs in DME patients on short-term follow-up, whereas intravitreal bevacizumab does not. Therefore, intravitreal steroids may be useful in DME with HEs in the fovea.

Indocyanine-green-guided targeted laser photocoagulation of capillary macroaneurysms in macular oedema: a pilot study

AIMS

In longstanding diabetic macular oedema (DME) or retinal vein occlusion (RVO), capillary macroaneurysms may develop. Indocyanine green angiography (ICGA) has been shown to optimise their detection. Here, we report the anatomical and functional outcome of the elective photocoagulation of capillary macroaneurysms.

METHODS

A retrospective, interventional, two-centre study. In eyes with chronic macular oedema and severe hard exsudates due to diabetic retinopathy or RVO, the presence of capillary macroaneurysms (defined by a diameter larger than 150 µm) was assessed by ICGA and optical coherence tomography (OCT). Capillary macroaneurysms were selectively photocoagulated, the presence of photothrombosis within the lumen being assessed by immediate OCT.

RESULTS

Four eyes from three patients with DME and five eyes from five patients with RVO were included. The median duration of visual loss was 4 years. Median initial visual acuity (VA) was 20/200. The median number of capillary macroaneurysms per eye was 2 (range, 1-8) and their median size was 410 µm (range, 154-603). Six months after photocoagulation, there was a significant reduction in macular thickness (mean±SD, 528 µm±200 vs 271 µm±152, p<0.05) and improvement of VA (mean log MAR, 0.82 vs 0.58, p<0.05).

CONCLUSIONS

During macular oedema with severe hard exsudates due to DME or RVO, systematic detection of capillary macroaneurysms by ICGA followed by their OCT-controlled photocoagulation may be of interest. These results may contribute to re-evaluate the role of photocoagulation in the management of longstanding macular oedema.

Effect of intravitreal bevacizumab on diabetic macular edema with hard exudates

Background

We evaluated the efficacy of intravitreal bevacizumab on diabetic macular edema with subfoveal and perifoveal hard exudates.

Materials and methods

Eleven eyes (11 patients) exhibiting diabetic macular edema with subfoveal and perifoveal hard exudates were included in this prospective, nonrandomized interventional pilot study. All patients were treated with monthly scheduled intravitreal bevacizumab injections for 6 months. Changes in the Early Treatment Diabetic Retinopathy Study best corrected visual acuity, amount of hard exudates on fundus photography, and macular edema detected by central subfield thickness on spectral domain optical coherence tomography after six serial injections, were assessed. The amount of hard exudates at each visit was evaluated as pixels in fundus photography, using an Adobe Photoshop program.

Results

Ten of 11 patients completed follow-up. The mean Early Treatment Diabetic Retinopathy Study best corrected visual acuity was 59.9±5.7 letters (Snellen equivalent, 20/63) at baseline evaluation. The best corrected visual acuity exhibited no significant difference at month 6 compared with at baseline (57.9±6.0 letters or 20/70 at month 6; P=0.085). At month 6, mean central subfield thickness decreased from 370.4±56.5 to 334.6±65.0 μm (P=0.009). The mean amount of hard exudates increased from 4467.1±2736.1 to 6592.4±2498.3 pixels at month 6 (P=0.022). No serious adverse events occurred.

Conclusion

Continuous intravitreal bevacizumab was found to have no benefit in visual acuity and amount of hard exudates, despite the improvement of macular edema at 6 months.

IVTA as adjunctive treatment to PRP and MPC for PDR and macular edema: a meta-analysis

BACKGROUND

To quantify the effect of a combination treatment of intravitreal triamcinolone acetonide (IVTA) injection, panretinal photocoagulation (PRP), and macular photocoagulation (MPC) in patients with proliferative diabetic retinopathy (PDR) and diabetic macular edema (DME).

METHODOLOGY/PRINCIPAL FINDINGS

We conducted a meta-analysis and searched for reports concerning IVTA injection combined with PRP for the treatment of PDR and DME using Medline, EMbase, Web of Science, the Cochrane Library, and Google according to Cochrane evaluation guidelines. The quality of the reports was evaluated using the Jadad score. Only four studies were ultimately included in this meta-analysis and the fixed-effects model was used. Treatment with IVTA injection combined with PRP and MPC significantly improved BCVA (p<0.001) from one to six months, compared with PRP and MPC alone. There was a statistically significant mean difference in central macular thickness (CMT), at the one-month follow-up (p<0.001). No evidence of publication bias was present. There was a low level of heterogeneity in this group of studies.

CONCLUSIONS/SIGNIFICANCE

This meta-analysis indicates that IVTA injection combined with PRP and MPC results in an improvement of BCVA, and CMT reduction in patients with PDR and DME.

Suprachoroidal drug infusion for the treatment of severe subfoveal hard exudates

PURPOSE

To evaluate the safety, feasibility, and preliminary efficacy of suprachoroidal drug delivery with a microcatheter for the treatment of severe subfoveal hard exudates (SHE) in retinal vasculopathies. Definitive treatments for SHE have not yet been identified and prognosis is unfavorable.

METHODS

In this prospective, interventional pilot study, six eyes of six patients with central or branch retinal vein occlusion or diffuse diabetic macular edema accompanied by massive refractory SHE underwent a single treatment with bevacizumab and triamcinolone administered to the submacular suprachoroidal space via a microcatheter introduced at the pars plana and advanced posteriorly. The main outcome measures included best-corrected visual acuity, vascular leakage, macular thickness, extent of SHE, and complications.

RESULTS

Mean follow-up was 12 months. Three eyes had central retinal vein occlusion, one had branch retinal vein occlusion, and two had chronic diabetic macular edema. Best-corrected visual acuity improved by ≥2 lines in 4 eyes and remained stable in 2 eyes. At 1 month to 2 months postprocedure, SHE was almost completely resolved in all eyes and macular edema was significantly reduced. There were no surgical or postoperative complications.

CONCLUSION

Suprachoroidal infusion of drugs can be effective in reabsorbing massive SHE.

Pharmacokinetics of triamcinolone acetonide for the treatment of macular edema

INTRODUCTION

The use of intravitreal triamcinolone acetonide (TA) for the treatment of various types of macular edema has been widespread, particularly for the last decade. Currently, there is a scant amount of evidence-based literature evaluating the pharmacokinetic profile of TA despite clinical data showing the efficacy of intravitreal TA for multiple forms of macular edema.

AREAS COVERED

This paper is an extensive review of human and experimental studies published on the pharmacokinetics of TA for the treatment of macular edema. The literature search was conducted via OVID, TRIP Database and EMBASE, up to April 2011.

EXPERT OPINION

The pharmacokinetic profile of TA is unpredictable and the agent has a time-limited therapeutic action due to its relatively short half-life. This has led to the need for repeated injections. Future research should investigate the pharmacokinetic profiles of TA when administered intravitreally, as well as through alternate routes in more robust studies.

Serum lipid profile in diabetic macular edema

PURPOSE

To evaluate the correlation of lipid profile and clinical presentation of macular edema in Type 2 diabetes mellitus (DM) patients.

MATERIALS AND METHODS

The study included 20 patients with chronic diabetic macular edema and plaque-like hard exudates (Group 1), 20 patients with diabetic macular edema (Group 2), and 20 DM patients but without retinopathy (Group 3). Diabetic retinopathy was classified according to the Early Treatment Diabetic Retinopathy Study grading system. Sample t test was used to evaluate the association between the fasting serum lipid [total cholesterol, triglyceride, low-density lipoprotein (LDL), high-density lipoprotein (HDL)], glycosylated hemoglobin (HbA1c), fasting blood glucose, creatinine levels, and the clinical findings. P values <.05 were considered statistically significant.

RESULTS

There was no difference between fasting serum lipids and HbA1c levels. Duration of diabetes was shorter in Group 3 than in Groups 1 and 2. Patients in Group 1 had longer duration of diabetes than others (P<.05). Creatinine levels in Group 1 were higher than in other groups (P<.05). Although there was no correlation between fasting blood glucose and HbA1c levels, HbA1c was higher in all three groups from the baseline-normal limits (P<.05).

CONCLUSION

No correlation was found between serum lipid levels and macular edema severity, but the duration of diabetes was demonstrated as a significant factor in the progression of macular edema. High HbA1c levels in all patients highlight the importance of intense glycemic control in diabetic patients.

Association of the extent of diabetic macular edema as assessed by optical coherence tomography with visual acuity and retinal outcome variables

PURPOSE

To determine whether the extensiveness of diabetic macular edema using a 10-step scale based on optical coherence tomography explains pretreatment variation in visual acuity and predicts change in macular thickness or visual acuity after laser photocoagulation.

METHODS

Three hundred twenty-three eyes from a randomized clinical trial of two methods of laser photocoagulation for diabetic macular edema were studied. Baseline number of thickened optical coherence tomography subfields was used to characterize diabetic macular edema on a 10-step scale from 0 to 9. Associations were explored between baseline number of thickened subfields and baseline fundus photographic variables, visual acuity, central subfield mean thickness (CSMT), and total macular volume. Associations were also examined between baseline number of thickened subfields and changes in visual acuity, CSMT, and total macular volume at 3.5 and 12 months after laser photocoagulation.

RESULTS

For baseline visual acuity, the number of thickened subfields explained no more variation than did CSMT, age and fluorescein leakage. A greater number of thickened subfields was associated with a greater baseline CSMT, total macular volume, area of retinal thickening, and degree of thickening at the center of the macula (r = 0.64, 0.77, 0.61-0.63, and 0.45, respectively) and with a lower baseline visual acuity (r = 0.38). Baseline number of thickened subfields showed no association with change in visual acuity (r < or = 0.01-0.08) and weak associations with change in CSMT and total macular volume (r from 0.11 to 0.35).

CONCLUSION

This optical coherence tomography based assessment of the extensiveness of diabetic macular edema did not explain additional variation in baseline visual acuity above that explained by other known important variables nor predict changes in macular thickness or visual acuity after laser photocoagulation.

Intravitreal bevacizumab versus combined bevacizumab-triamcinolone versus macular laser photocoagulation in diabetic macular edema

PURPOSE

To evaluate the additive effect of triamcinolone to bevacizumab in comparison to standard macular laser photocoagulation versus bevacizumab in the management of diabetic macular edema (DME).

METHODS

In a prospective, randomized clinical trial, 130 eyes of 110 patients with type 2 diabetes with DME were included. Eligible eyes were randomly assigned to 1.25 mg intravitreal bevacizumab (42 eyes) (IVB group) or combination of 1.25 mg bevacizumab and 2 mg triamcinolone acetonide (41 eyes) (IVB+IVT group) or macular laser photocoagulation (47 eyes) (MPC). Central macular thickness (CMT) and visual acuity changes at week 6 and 16 were assessed.

RESULTS

The mean age of the patients was 57 -/+7 years. Patients were followed 16 weeks. At week 6, all the three groups showed significant reduction in CMT but the reductions for IVB and IVB+IVT were significantly more than MPC (p<0.001). At week 16, the response was not stable for IVB (p<0.001), but IVB+IVT maintained its superior status to MPC (p<0.001). At week 16, visual acuities were essentially unchanged for the two groups of MPC and IVB and improvement for IVB+IVT was marginal and at most was 0.1 log MAR. No patient developed uveitis, endophthalmitis, or thromboembolic event.

CONCLUSIONS

Single intravitreal bevacizumab or triamcinolone plus bevacizumab injection brought about significantly greater macular thickness reduction in diabetic patients in comparison to standard laser treatment. However, the response for bevacizumab alone was short-lived. Reduction in macular thickness was only marginally associated with visual acuity improvement in the triamcinolone plus bevacizumab injection group.

Diabetic macular edema: what is focal and what is diffuse?

PURPOSE

To review the available information on classification of diabetic macular edema (DME) as focal or diffuse.

DESIGN

Interpretive essay.

METHODS

Literature review and interpretation.

RESULTS

The terms focal diabetic macular edema and diffuse diabetic macular edema frequently are used without clear definitions. Published definitions often use different examination methods and often are inconsistent. Evaluating published information on the prevalence of focal and diffuse DME, the responses of focal and diffuse DME to treatments, and the importance of focal and diffuse DME in assessing prognosis is hindered because the terms are used inconsistently. A newer vocabulary may be more constructive, one that describes discrete components of the concepts such as extent and location of macular thickening, involvement of the center of the macula, quantity and pattern of lipid exudates, source of fluorescein leakage, and regional variation in macular thickening and that distinguishes these terms from the use of the term focal when describing one type of photocoagulation technique. Developing methods for assessing component variables that can be used in clinical practice and establishing reproducibility of the methods are important tasks.

CONCLUSIONS

Little evidence exists that characteristics of DME described by the terms focal and diffuse help to explain variation in visual acuity or response to treatment. It is unresolved whether a concept of focal and diffuse DME will prove clinically useful despite frequent use of the terms when describing management of DME. Further studies to address the issues are needed.

Adverse events after intravitreal triamcinolone in patients with and without uveitis

PURPOSE

To evaluate the rates of adverse ocular events after intravitreal triamcinolone acetonide (IVTA) injection in patients with and without uveitis.

DESIGN

Retrospective observational case series.

PARTICIPANTS

Two hundred twenty-two eyes of 173 patients were included in the study: 45 eyes of 31 patients with macular edema (ME) due to uveitis and 177 eyes of 142 patients with ME secondary to other etiologies.

METHODS

Retrospective review of patients who received IVTA at the Cole Eye Institute for ME attributable to various causes between the years 2001 and 2005. Data review of clinical records included patient demographics, etiology of ME, and adverse outcomes after injection. Rates of adverse outcomes in patients with and without uveitis were compared.

MAIN OUTCOME MEASURES

Intraocular pressure (IOP) elevation and posterior subcapsular cataract (PSC) progression.

RESULTS

Uveitis patients were significantly younger, more likely to be female, and more likely to have had prior posterior sub-Tenon's capsule steroid injection and/or glaucoma therapy than their nonuveitis counterparts. In a multivariate analysis adjusting for the differences in these factors, the presence of uveitis was the strongest risk factor for an adverse IOP event (odds ratio, 2.5; 95% confidence interval [CI], 1.0-6.1; P = 0.05). The odds of having a documented increase in PSC after IVTA injection were 5.6 times greater in uveitis eyes (P = 0.007; 95% CI, 1.6-19.6).

CONCLUSIONS

Intraocular pressure elevation and PSC progression occurred with greater frequency in uveitis patients receiving IVTA. Patients with uveitis treated with IVTA should be counseled about these risks and monitored closely.

Quantitative evaluation of reduction of plaque-like hard exudates in diabetic macular edema after intravitreal triamcinolone injection

BACKGROUND

To describe a new method of quantifying the amount of plaque-like hard exudates after intravitreal triamcinolone acetonide injection in diabetic macular edema.

METHODS

This study included 22 eyes of 14 patients (mean age, 63 years) with chronic diabetic macular edema and plaque-like hard exudates. The patients were injected with a single dose of 4 mg intravitreal triamcinolone acetonide. The optic disc size as relative size unit was taken to quantify the hard exudates: Total areas of exudates and the optic nerve head were computed from fundus pictures with a digital analysis program on magnified images. The former was divided by the latter, and the results were expressed as a percentage value. The ratio was used to track improvements in a given eye over 6 months.

RESULTS

Average ratio of hard exudates to optic nerve head area reduced to 81% of its initial value at 1 month (P=0.007), to 54% at 3 months (P<0.001) and to 41% at 6 months (P<0.001).

CONCLUSIONS

The new method allowed detection of a significant reduction of ratio of hard exudates to optic disc area of diabetic plaque-like hard exudates following 4 mg intravitreal triamcinolone.

The use of intravitreal corticosteroids, evidence-based and otherwise

PURPOSE OF REVIEW

To provide a current update on the use of intravitreal corticosteroids as a treatment for a variety of retinal diseases.

RECENT FINDINGS

Pharmacokinetic studies demonstrate that a single 4 mg injection of intravitreal triamcinolone acetonide is present in the vitreous for up to 3 months. Many recent studies demonstrate a significant reduction in macular edema often with a significant improvement in vision for up to several months followed by a waning of treatment effect and recurrence of macular edema. Retreatments have been shown to be efficacious. Intravitreal triamcinolone acetonide may help lead to a reduction in subfoveal hard exudates in diffuse diabetic macular edema. It has been shown to be a more potent treatment than sub-Tenon's and retrobulbar triamcinolone acetonide for persistent macular edema. It may also be a significant adjunctive treatment for choroidal neovascularization treated with photodynamic therapy. Intravitreal corticosteroid implants have also been shown to be beneficial in early trials for persistent macular edema.

SUMMARY

Intravitreal triamcinolone acetonide provides a potent short-term treatment for persistent macular edema and may be a useful adjunctive treatment for choroidal neovascularization. It remains to be determined whether intravitreal corticosteroids can provide long-term visual gain or stabilization. The side-effect profile of intravitreal corticosteroids is significant with corticosteroid-induced intraocular pressure rises. With longer-term studies, the rate of posterior subcapsular cataract formation is higher than previously reported, and there is a small but potential risk of endophthalmitis.

Current treatment approaches in diabetic macular edema

PURPOSE

To review current treatment approaches in diabetic macular edema (DME).

METHODS

The underlying pathopathology, classifications and diagnostic examination techniques including fluorescein angiography, optical coherence tomography and stereoscopic biomicroscopy. Treatment modalities with focal or grid argon laser photocoagulation, pars plana vitrectomy with and without peeling of the inner limiting membrane (ILM), as well as intravitreal injections using triamcinolone acetonide or novel vascular endothelial growth factor (VEGF) inhibitors are described.

RESULTS

DME results from a series of biochemical and cellular changes, causing progressive leakage and exudation. Focal and grid photocoagulation remains the standard care for diabetic maculopathy. However, the availability of new agents raises the possibility of improvements if significant benefits can be validated in randomized clinical trials. Posterior vitreous attachments play a critical role through several mechanical or physiological mechanisms. Vitrectomy without ILM removal seems to be effective in reducing the retinal thickness and improving visual acuity.

CONCLUSION

A proper evaluation of the vitreous and retina is fundamental to select the most appropriate treatment approach in DME. While small microaneurysms with focal DME may be treated by conventional focal photocoagulation, diffuse DME which do not respond to grid photocoagulation may benefit from intravitreal injections using triamcinolone acetonide or novel VEGF inhibitors. Eyes with DME and additional vitreous traction may benefit from pars plana vitrectomy without ILM peeling. A combination of laser, pharmacological and surgical treatment modalities may be necessary to maintain central vision in eyes with DME.

Intravitreal triamcinolone as an adjunct in the treatment of concomitant proliferative diabetic retinopathy and diffuse diabetic macular oedema

PURPOSE

To investigate if triamcinolone acetonide (TA) can be an adjunct to laser treatment in patients with concomitant non-high-risk proliferative diabetic retinopathy (PDR) and diffuse clinically significant diabetic macular oedema (CSMO).

METHODS

This prospective, interventional and comparative clinical study included 32 eyes of 16 patients with bilateral concomitant non-high-risk PDR and diffuse CSMO. Each patient received 4 mg intravitreal TA for the eye with worse visual acuity (study group) and macular focal and grid laser photocoagulation (MP) for the other eye (control group). One month later, each patient received four sessions of panretinal photocoagulation for both eyes plus MP for the eyes in the study group. The visual and angiographic results of both groups were compared.

RESULTS

In the study group, the mean visual acuity (VA) improved from 0.12 +/- 2.3 lines at the baseline to 0.19 +/- 3.1 (P = 0.004), 0.20 +/- 3.2 (P = 0.004), 0.19 +/- 3.6 (P = 0.009) and 0.19 +/- 3.3 lines (P = 0.091) at the 1-, 3-, 6- and 9-month follow-up intervals, respectively. The macular oedema was found to be resolved in 11 eyes (69%) and decreased in five eyes (31%). In the control group, the mean VA deteriorated progressively from 0.41 +/- 3.1 lines at the baseline to 0.20 +/- 3.1 lines (P = 0.026) at the end of the study and the macular oedema decreased only in three eyes (19%) at the sixth follow-up month.

CONCLUSIONS

During the follow-up period of the study, intravitreal TA as an adjunct in the treatment of concomitant non-high-risk PDR and diffuse CSMO led to a more-favourable clinical outcome than conventional laser treatment.