Intravitreal Triamcinolone Acetonide for Treatment of Central Retinal Vein Occlusion

Intravitreal dexamethasone implant versus triamcinolone acetonide for macular oedema of central retinal vein occlusion: quantifying efficacy and safety

PURPOSE

Among the retinal vascular diseases, burden of retinal vein occlusion is most common immediately after diabetic retinopathy. Intravitreal corticosteroids are gaining popularity in managing macular edema (ME) of RVO. Our study compares efficacy and safety of intravitreal triamcinolone (IVTA) and dexamethasone implant (IVD) over 6 months.

METHODS

This comparative, prospective, randomized study on 40 patients of non-ischemic central RVO with significant ME (> 330 μm) of < 3 months duration. Study was done at Army Research Hospital between Sep-2012 and May-2014 in accordance to Helsinki Declaration. IVD group (n = 20) received Ozurdex® while IVTA group (n = 20) received triamcinolone-acetonide (4 mg/0.1 ml), followed up at day-1 and weeks 4, 8, 12, 24.

RESULTS

At 6 months, mean improvement in best corrected visual acuity and retinal thickness (CMT) in the IVD group was 0.43 logmar and 323 μm and in IVTA group was 0.49 logmar and 322 μm respectively. Proportion of patients achieving ≥ 15 letters was about 40% in both groups. IOP rise was significantly higher in IVTA group at 12 and 24 weeks. In IVTA group ≥ 10 mmHg IOP rise was seen in 60% of patients, 41.6% among them had > 35 mmHg and 66% needed combination treatment and failed to reach baseline line IOP at 6 months. In IVD group, 5 pts had IOP rise with all being < 26 mmHg and were easily managed with single agent with IOP reaching baseline by 6th month in all pts. Relative risk of IOP rise with IVTA is 2.4 times higher compared to IVD. Cataract progression and cataract surgeries were required at significantly higher rates in IVTA group. In IVTA group, cataract progression was seen in 35% patients, with 71.5% requiring cataract surgery at 6 months. IVD group, 10% patients had cataract progression while none required surgery at 6 months. Relative risk of cataract progression with IVTA is 3.5 times higher compared to IVD.

CONCLUSION

Intravitreal steroids are effective in managing macular edema of retinal vein occlusion, while newer formulation of sustained release dexamethasone implant is significantly safer than IVTA.

Systematic literature review of treatments for management of complications of ischemic central retinal vein occlusion

Background

To understand the clinical and economic outcomes of treatments for managing complications of ischemic central retinal vein occlusion (iCRVO).

Methods

We conducted a systematic literature review by searching multiple databases and ophthalmology conferences from 2004 to 2015. Studies published in English language and populations of age ≥45 years were included. For clinical endpoints, we defined eligibility criteria as randomized controlled trials, prospective before-and-after study designs, and non-randomized studies reporting on treatments in patients with iCRVO. For economic endpoints, all types of study design except cost-of-illness studies were included. We evaluated the definitions of ischemia, clinical and economic endpoints, and rate of development of complications. Risk of bias was assessed for clinical studies using the Cochrane risk-of-bias tool.

Results

A total of 20 studies (1338 patients) were included. Treatments included anti-vascular endothelial growth factors (anti-VEGFs), steroids, and procedures primarily targeting macular edema and neovascularization. Ischemia was not defined consistently in the included studies. The level of evidence was mostly low. Most treatments did not improve visual acuity significantly. Development of treatment complications ranged from 11 to 57 %. Incremental cost-effectiveness ratios reported for anti-VEGFs and steroids were below the accepted threshold of GB£30,000, but considering such treatments only ameliorate disease symptoms they seem relatively expensive.

Conclusions

There is a lack of evidence for any intervention being effective in iCRVO, especially in the prevention of neovascularisation. iCRVO poses a significant clinical and economic burden. There is a need to standardize the definition of ischemia, and for innovative treatments which can significantly improve visual outcomes and prevent neovascular complications.

Choroidal thickness measurements with optical coherence tomography in branch retinal vein occlusion

AIM

To evaluate central macular thickness (CMT) and mean choroidal thickness (MCT) in eyes with branch retinal vein occlusion (BRVO), before and after ranibizumab treatment using spectral domain-optical coherence tomography (SD-OCT).

METHODS

Forty-two patients with unilateral BRVO and macular edema were included in this study. There were 25 men and 17 women. Using SD-OCT, choroidal thickness was measured at 500 µm intervals up to 1500 µm temporal and nasal to the fovea. MCT was calculated based on the average of the 7 locations. All the eyes with BRVO were treated with intravitreal ranibizumab (0.5 mg/0.05 mL). Comparisons between the BRVO and fellow eyes were analyzed using Mann-Whitney U test. Pre-injection and post-injection measurements were analyzed using Wilcoxon test and repeated measure analysis.

RESULTS

At baseline, there was a significant difference between the BRVO and fellow eyes in MCT [BRVO eyes 245 (165-330) µm, fellow eyes 229 (157-327) µm] and CMT [BRVO eyes 463 (266-899) µm, fellow eyes 235 (148-378) µm (P=0.041, 0.0001, respectively)]. Following treatment, CMT [295 (141-558) µm] and MCT [229 (157-329) µm] decreased significantly compared to the baseline measurements (P=0.001, 0.006, respectively). Also BCVA (logMAR) improved significantly (P=0.0001) in the BRVO eyes following treatment. After treatment CMT [BRVO eyes 295 (141-558) µm, fellow eyes 234 (157-351) µm] and MCT [BRVO eyes 229 (157-329) µm, fellow eyes 233 (162-286) µm] values did not reveal any significant difference in BRVO eyes and fellow eyes (P=0.051, 0.824, respectively).

CONCLUSION

In eyes with BRVO, CMT and MCT values are greater than the fellow eyes, and decrease significantly following ranibizumab injection.

Predictors of short-term outcomes related to central subfield foveal thickness after intravitreal bevacizumab for macular edema due to central retinal vein occlusion

AIM

To investigate the predictive factors for short-term effects of intravitreal bevacizumab injections on central subfield foveal thickness (CSFT) in patients with macular edema (ME) secondary to central retinal vein occlusion (CRVO).

METHODS

This was a retrospective study in 60 eyes treated with intravitreal bevacizumab injections for ME due to CRVO. Follow-up was three months. The Early Treatment Diabetic Retinopathy Study (ETDRS) score and CSFT measured by spectral-domain optical coherence tomography (SD-OCT) were used to observe the changes in best-corrected visual acuity (BCVA). Baseline BCVA, CSFT, age, CRVO duration and the presence of cystoid macular edema (CME) or subretinal fluid (SRF) were analyzed as potential predictive factors of the effects of intravitreal bevacizumab injections.

RESULTS

BCVA improved from 0.9 logMAR at baseline to 0.6 logMAR at 3mo, which was associated with a significant reduction in CSFT from 721 µm to 392 µm 3mo after injection. About 50% of CME cases and more than 90% of SRF cases responded to treatment with a complete resolution at 3mo. Age (P=0.036) and low baseline CSFT (P=0.037) were associated with a good 3-month prognosis. Patients >60 years old achieved better CME resolution (P=0.031) and lower CSFT at 3mo (305 µm vs 474 µm, P=0.003).

CONCLUSION

Intravitreal bevacizumab significantly improved visual acuity and CSFT in patients with CRVO after 3mo. Older age and lower baseline CSFT were good predictors of short-term CSFT outcomes. The retinal thickness response to bevacizumab might depend on the resolution of CME rather than SRF.

Intravitreal steroids versus observation for macular edema secondary to central retinal vein occlusion

BACKGROUND

Central retinal vein occlusion (CRVO) is a common retinal vascular abnormality associated with conditions such as hypertension, diabetes, glaucoma, and a wide variety of hematologic disorders. Macular edema (ME) represents an important vision-threatening complication of CRVO. Intravitreal steroids (IVS), such as triamcinolone acetonide, have been utilized to treat macular edema stemming from a variety of etiologies and may be a treatment option for CRVO-ME.

OBJECTIVES

To explore the effectiveness and safety of intravitreal steroids in the treatment of CRVO-ME.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2014 Issue 10), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to November 2014), EMBASE (January 1980 to November 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 13 November 2014. For all included primary studies, we used The Science Citation Index (3 December 2014) and manually reviewed reference lists to identify other possible relevant trials.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that compared intravitreal steroids, of any dosage and duration of treatment of at least six months, with observation for the treatment of CRVO-ME.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts identified from the electronic searches and assessed full-text articles from potentially eligible trials. Two review authors independently assessed trial characteristics, risk of bias, and extracted data from included trials. We contacted investigators of included trials for desired data not provided in the trial reports.

MAIN RESULTS

We included two RCTs that enrolled a total of 708 participants with CRVO-ME. SCORE compared triamcinolone acetonide intravitreal injections (n = 165) with observation (n = 72); GENEVA compared dexamethasone intravitreal implants (n = 290) with sham injections (n = 147). We observed characteristics indicative of high risk of bias due to incomplete outcome data in SCORE and selective outcome reporting in GENEVA. Loss to follow-up was high with 10% in the steroid groups and almost twice as much (17%) in the observation group. GENEVA enrolled participants with both branch and central retinal vein occlusion, but did not present subgroup data for the CRVO-ME population. A qualitative assessment of the results from GENEVA indicated that the dexamethasone implant was not associated with improvement in visual acuity after six months among participants with CRVO-ME. Although the SCORE investigators reported that participants treated with 1 mg (n = 82) or 4 mg (n = 83) triamcinolone intravitreal injections were five times more likely to have gained 15 letters or more in visual acuity compared with participants in the observation group (1 mg; risk ratio (RR): 5.27; 95% confidence interval (CI) 1.62 to 17.15; 4 mg RR 4.92; 95% CI 1.50 to 16.10) by the eighth-month follow-up examination, the average visual acuity decreased in all three groups. However, eyes treated with triamcinolone lost fewer letters than participants in the observation group at 8 months (1 mg mean difference (MD): 8.70 letters, 95% CI 1.86 to 15.54; 4 mg MD: 9.80 letters, 95% CI 3.32 to 16.28). A higher incidence of adverse events was noted with IVS therapy when compared with observation alone. As many as 20% to 35% of participants experienced an adverse event in the IVS groups compared with 8% of participants in the observation group of the SCORE study. The GENEVA investigators reported 63% in the treatment arm versus 43% in the observation arm experienced an adverse event. The most commonly encountered adverse events were elevated intraocular pressure, progression of cataracts, and retinal neovascularization. We graded the quality of evidence as low due to study limitations, imprecision of treatment estimates, and selective outcome reporting.

AUTHORS' CONCLUSIONS

The two RCTs reviewed herein provide insufficient evidence to determine the benefits of IVS for individuals with CRVO-ME. The improvement in visual acuity noted in the SCORE trial should be interpreted with caution as outcome data were missing for a large proportion of the observation group. Adverse events were observed more often with IVS treatment compared with observation/no treatment.

Three intravitreal bevacizumab versus two intravitreal triamcinolone injections in recent onset central retinal vein occlusion

PURPOSE

To evaluate the effects of repeated intravitreal injections of bevacizumab (IVB) versus triamcinolone acetonide (IVT) in the treatment of acute central retinal vein occlusion (CRVO).

METHODS

In this randomized clinical trial, 86 eyes with recent onset (<12 weeks) CRVO were assigned to two groups: IVB group (43 eyes) that received three monthly injections of 1.25 mg of IVB, and IVT group (43 eyes) that received two injections of 2 mg IVT 2 months apart. Outcomes were best-corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure (IOP) changes.

RESULTS

Mean BCVA improved significantly at 6 months in both groups; from 0.87 ± 0.49 to 0.41 ± 0.35 logMAR in IVB group, and from 0.81 ± 0.45 to 0.62 ± 0.48 logMAR in IVT group (p < 0.001). However, between-group differences reach a significant level at months 4 (p = 0.003) and 6 (p < 0.001) in favour of the IVB group. In terms of CMT reduction, the difference between the groups was statistically significant (p = 0.002) at month 6. Significant differences were noted more in the ischaemic cases in favour of the IVB group. Mean IOP rise was significantly higher in the IVT group at all visits.

CONCLUSIONS

Both 3-times monthly IVB injections and 2-times IVT injections could be effective in cases with recent onset CRVO up to 6 months. However, considering the better outcomes after IVB injections and the potential complications of IVT injections, we would recommend prescheduled repeated IVB injections for such cases. The observed favourable responses were more pronounced in the ischaemic types; nevertheless, this should be confirmed in larger studies.

Meta-analysis of the effect of intravitreal bevacizumab versus intravitreal triamcinolone acetonide in central retinal vein occlusion

PURPOSE

To further evaluate the effect of intravitreal bevacizumab (IVB) for the treatment of central retinal vein occlusion (CRVO) by meta-analysis.

METHODS

Pertinent publications were identified through PubMed, EMBASE, and the Cochrane Controlled Trials Register up to January 30, 2013. Changes in central macular thickness (CMT) and best-corrected visual acuity (BCVA) were extracted at 4, 12, and 24 weeks after treatment, and a meta-analysis was carried out to compare results between groups receiving IVB and intravitreal triamcinolone acetonide (IVTA).

RESULTS

One randomized controlled trial and 4 comparative studies were identified and included. All of the funnel plots, the Egger's method and Begg method did not show publication bias. Our meta-analysis revealed that BCVA and CMT at 4, 12, and 24 weeks after treatment did not vary significantly between the IVB groups and IVTA groups (BCVA: at 4 weeks, P=0.27; at 12 weeks, P=0.51; at 24 weeks, P=0.64; CMT at 4 weeks, P=0.88; at 12 weeks, P=0.57; at 24 weeks, P=0.64). However, the rate of intraocular pressure rise after intravitreal injection varied significantly between the IVB groups and IVTA groups (P<0.001).

CONCLUSIONS

Our results showed a similar improvement in BCVA and CMT among CRVO patients was obtained after intravitreal injections of both IVB, or IVTA, while the rate of IOP rise was significantly higher in the latter.

Steroids and macular edema from retinal vein occlusion

PURPOSE

The possibility of applying long-lasting steroids, such as triamcinolone and subsequently dexamethasone implant, directly in the eye, without the systemic side effects observed after their oral or intravenous administration, aroused great enthusiasm among ophthalmologists.

METHODS AND RESULTS

The SCORE study, a multicenter clinical trial, compared the efficacy and safety of 1-mg and 4-mg doses of preservative-free intravitreal triamcinolone with observation in central retinal vein occlusion (CRVO) participants with macular edema secondary to perfused CRVO. This study marked a turning point in the management of retinal vein occlusion (RVO), since it was the first report on an effective treatment of macular edema due to CRVO. But in branch retinal vein occlusion (BRVO), the SCORE study showed no difference in visual acuity for the standard care group compared with the triamcinolone groups; however, the rates of adverse events (particularly elevated intraocular pressure and cataract) were highest in the 4-mg group. The authors concluded that laser grid photocoagulation should remain the benchmark against which other treatments should be compared. The Geneva Study, a randomized, controlled, clinical trial, conducted to evaluate the safety and efficacy of an intravitreal implant that delivers sustained levels of dexamethasone (Ozurdex™), studied the largest group of RVO patients with macular edema (1267 patients), including 35% CRVO and 65% BRVO. The study demonstrated that this slow-release device could both reduce the risk of vision loss and improve the speed and incidence of visual improvement in eyes with macular edema secondary to CRVO and BRVO, with fewer side effects, such as elevation of intraocular pressure or cataract. Other ongoing studies evaluate the safety and efficacy of anti-vascular endothelial growth factor injection; preliminary results showed that these therapies are effective in decreasing macular edema and improving visual acuity, with fewer ocular adverse effects, but their duration of action seems limited.

CONCLUSIONS

These recent studies result in a great change in the management of macular edema from RVO. Unfortunately, long-term studies on safety and efficacy are not yet available, and further studies will have to show whether the short-term benefits are only transient or may finally lead to a long-lasting improvement in vision.

Dexamethasone intravitreal implant in combination with laser photocoagulation for the treatment of diffuse diabetic macular edema

PURPOSE

To evaluate Ozurdex (dexamethasone intravitreal implant [DEX implant]; Allergan, Inc, Irvine, CA) 0.7 mg combined with laser photocoagulation compared with laser alone for treatment of diffuse diabetic macular edema (DME).

DESIGN

Randomized, controlled, multicenter, double-masked, parallel-group, 12-month trial.

PARTICIPANTS

Two hundred fifty-three patients with retinal thickening and impaired vision resulting from diffuse DME in at least 1 eye (the study eye) were enrolled.

INTERVENTION

Patients were randomized to treatment in the study eye with DEX implant at baseline plus laser at month 1 (combination treatment; n = 126) or sham implant at baseline and laser at month 1 (laser alone; n = 127) and could receive up to 3 additional laser treatments and 1 additional DEX implant or sham treatment as needed.

MAIN OUTCOME MEASURES

The primary efficacy variable was the percentage of patients who had a 10-letter or more improvement in best-corrected visual acuity (BCVA) from baseline at month 12. Other key efficacy variables included the change in BCVA from baseline and the area of vessel leakage evaluated with fluorescein angiography. Safety variables included adverse events and intraocular pressure (IOP).

RESULTS

The percentage of patients who gained 10 letters or more in BCVA at month 12 did not differ between treatment groups, but the percentage of patients was significantly greater in the combination group at month 1 (P<0.001) and month 9 (P = 0.007). In patients with angiographically verified diffuse DME, the mean improvement in BCVA was significantly greater with DEX implant plus laser treatment than with laser treatment alone (up to 7.9 vs. 2.3 letters) at all time points through month 9 (P ≤ 0.013). Decreases in the area of diffuse vascular leakage measured angiographically were significantly larger with DEX implant plus laser treatment through month 12 (P ≤ 0.041). Increased IOP was more common with combination treatment. No surgeries for elevated IOP were required.

CONCLUSIONS

There was no significant between-group difference at month 12. However, significantly greater improvement in BCVA, as demonstrated by changes from baseline at various time points up to 9 months and across time based on the area under the curve analysis, occurred in patients with diffuse DME treated with DEX implant plus laser than in patients treated with laser alone.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Inflammation in retinal vein occlusion

Retinal vein occlusion is a common, vision-threatening vascular disorder. The role of inflammation in the pathogenesis and clinical consequences of retinal vein occlusion is a topic of growing interest. It has long been recognized that systemic inflammatory disorders, such as autoimmune disease, are a significant risk factor for this condition. A number of more recent laboratory and clinical studies have begun to elucidate the role inflammation may play in the molecular pathways responsible for the vision-impairing consequences of retinal vein occlusion, such as macular edema. This improved understanding of the role of inflammation in retinal vein occlusion has allowed the development of new treatments for the disorder, with additional therapeutic targets and strategies to be identified as our understanding of the topic increases.

Therapeutic potential of intravitreal pharmacotherapy in retinal vein occlusion

Retinal vein occlusion (RVO) is the most common visually disabling disease affecting the retina after diabetic retinopathy. Although the disease entity has long been known, its management is still controversial. Macular edema is the main reason for decreased visual acuity (VA) in this retinal vascular disorder. Recently the vitreous cavity has increasingly been used as a reservoir of drugs for the direct treatment of macular edema through intravitreal injection route. The most widely injected drugs so far have been triamcinolone acetonide (TA) and bevacizumab. The objective of this review is to evaluate the evidence and discuss the rationale behind the recent suggestions that intravitreal pharmacotherapy by corticosteroids and anti-vascular endothelial growth factors may be useful in the treatment of retinal vein occlusion.

Hypothalamic-pituitary-adrenal axis function following intravitreal triamcinolone acetonide injection

To evaluate the pituitary-adrenal axis function by means of the adrenocorticotropic hormone (ACTH) stimulation test following a single intravitreal injection of triamcinolone acetonide (IVTA). Prospective comparative clinical interventional study. Twenty-eight patients (28 eyes) received a single IVTA (4 mg in 0.1 ml) for macular edema. The basal cortisol level and the response to 1 μg adrenocorticotropic hormone stimulation were determined on the morning before IVTA injection and at 1 day and 1, 2, and 4 weeks after IVTA injection. Results were compared with those obtained from a control group of 50 healthy subjects. All patients in the study had normal basal cortisol and normal response to ACTH challenge before receiving IVTA. 1 day following IVTA, basal cortisol was suppressed in one patient in the study group. Fasting serum cortisol levels at 1, 2, and 4 weeks after IVTA injection were normal in all patients in the study group. 1 day following IVTA, the peak response to ACTH at 30 min was blunted in four patients (14.3 % of the study group, p = 0.05) and the cortisol response at 60 min was suppressed (p = 0.009). 1 week following IVTA, the response to ACTH challenge was blunted in only one patient. A single IVTA injection may be associated with impaired hypothalamic-pituitary-adrenal function in some patients during the first 24 h following IVTA.

Intravitreal bevacizumab (Avastin) in the treatment of macular edema secondary to retinal vein occlusion

Objective

To evaluate efficacy and safety of intravitreal injections of bevacizumab in the treatment of macular edema secondary to retinal vein occlusion (RVO).

Methods

Prospective study, noncomparative, interventional case series. Twelve consecutive patients (12 eyes) with macular edema associated with nonischemic retinal vein occlusion were treated with intravitreal bevacizumab (1.25 mg). All subjects underwent standardized ophthalmic evaluation at baseline and at weeks 1, 4, 12, and 24, consisting of visual acuity (VA) measurement using ETDRS charts, and imaging with ocular coherence tomography evaluating changes in foveal thickness (FT) and macular volume (MV).

Results

The median age was 66 years (± 4.16), and the median duration of symptoms was 4 months (± 1.81). There were six cases of inferior branch vein occlusion and six cases of superior branch retinal vein occlusion. Mean VA improved from 1.32 ± 0.24 (logMAR values) at baseline to 0.8 ± 0.15 (p = 0.0003) at the 6-month follow-up. The macular edema responded promptly, and a trend to restoration of normal macular anatomy was observed at by the seventh day. Mean FT improved from 615.50 ± 116.29 microns to 420 ± 72.53 microns (p = 0.001), and the mean MV improved from 19.81 ± 2.31mm3 to 9.23 ± 1.38 (p = 0.0001) at the 6-month follow-up.

Hemodilution therapy using automated erythrocytapheresis in central retinal vein occlusion: results of a multicenter randomized controlled study

BACKGROUND

Central retinal vein occlusion (CRVO) leads to poor visual outcome in most eyes. Abnormal hemorheology was suspected to play a major role in its pathogenesis. CRVO treatment is still a matter of debate but several studies have pointed out the efficacy of isovolumic hemodilution. The aim of this study was to assess the feasibility and efficacy of hemodilution using automated erythrocytapheresis in recent-onset CRVO.

METHODS

In this prospective randomized controlled multicenter study, 61 consecutive CRVO patients were enrolled when they met the following criteria: CRVO lasting for 3 weeks or less, visual acuity ranging from 20/200 to 20/32, age between 18 and 85 years, no diabetes, no uncontrolled systemic hypertension, no antiplatelet or anticoagulant therapy, hematocrit higher than 38%, and signed informed consent. Patients were randomly assigned to the hemodilution group (n = 31) or to the control group (n = 30). Hemodilution therapy consisted of one session of erythrocytapheresis on outpatient basis, followed by additional session(s) for 6 weeks if needed. Target hematocrit was 35%. Follow-up was 12 months.

RESULTS

No statistical differences in age, associated risk factors, or CRVO characteristics were observed at baseline between both groups. Mean visual acuity was equivalent to 20/80 in the hemodilution group and to 20/63 in the control group (non-significant difference). In the treated group, mean number of hemodilution sessions was 3.3 (range, 1 to 6), and no major side-effects occurred. At the 12-month follow-up visit, 64.5% of the hemodilution group had visual acuity of 20/40 or better compared to 40% of the control group (p = .048). Visual change was a gain of 1.7 ETDRS line in the hemodilution group versus a loss of 2.3 lines in the control group (p = .007). There was less conversion into an ischemic form in the hemodilution group (11%) than in the control group (50%, p = .004). Mean final retinal thickness was 289 μm in the hemodilution group versus 401 μm in the control group (p = .068).

CONCLUSIONS

This multicenter controlled randomized study demonstrated that automated erythrocytapheresis is a safe and effective tool for performing hemodilution and confirmed that hemodilution therapy can improve the final prognosis of CRVO when applied in the early phase of the disease.

Natural history of central retinal vein occlusion: an evidence-based systematic review

OBJECTIVE

To describe the natural history of central retinal vein occlusion (CRVO) based on the best available evidence from the literature.

CLINICAL RELEVANCE

Central retinal vein occlusion is a common sight-threatening retinal vascular disease. Despite the introduction of new interventions, the natural history of CRVO is unclear.

METHODS

Systemic review of all English language articles retrieved using a keyword search of MEDLINE, EMBASE, Current Contents, and the Cochrane Library to November 13, 2008. This was supplemented by hand-searching references of review articles published within the last 5 years. Two investigators independently identified all relevant observational studies evaluating the natural history of RVO and all clinical trials evaluating interventions for CRVO; an untreated control arm was included.

RESULTS

Of 5966 citations retrieved, 53 studies were reviewed, providing 3271 eyes with CRVO for analysis of its natural history. Visual acuity (VA) was generally poor at baseline (<20/40) and decreased further over time. Although 6 studies reported an improvement in VA, none of these improvements resulted in VA better than 20/40. Up to 34% of eyes with nonischemic CRVO converted to ischemic CRVO over a 3-year period. In ischemic CRVO cases, neovascular glaucoma developed in at least 23% of eyes within 15 months. In nonischemic CRVO cases, macular edema resolved in approximately 30% of eyes over time, and subsequent neovascular glaucoma was rare.

CONCLUSIONS

Untreated eyes with CRVO generally had poor VA, which declined further over time. One quarter of eyes with nonischemic CRVO converted to ischemic CRVO.

Randomized, sham-controlled trial of dexamethasone intravitreal implant in patients with macular edema due to retinal vein occlusion

OBJECTIVE

To evaluate the safety and efficacy of dexamethasone intravitreal implant (DEX implant; OZURDEX, Allergan, Inc., Irvine, CA) compared with sham in eyes with vision loss due to macular edema (ME) associated with branch retinal vein occlusion (BRVO) or central retinal vein occlusion (CRVO).

DESIGN

Two identical, multicenter, masked, randomized, 6-month, sham-controlled clinical trials (each of which included patients with BRVO and patients with CRVO).

PARTICIPANTS

A total of 1267 patients with vision loss due to ME associated with BRVO or CRVO.

INTERVENTION

A single treatment with DEX implant 0.7 mg (n = 427), DEX implant 0.35 mg (n = 414), or sham (n = 426).

MAIN OUTCOME MEASURES

The primary outcome measure for the pooled data from the 2 studies was time to achieve a > or =15-letter improvement in best-corrected visual acuity (BCVA). Secondary end points included BCVA, central retinal thickness, and safety.

RESULTS

After a single administration, the time to achieve a > or =15-letter improvement in BCVA was significantly less in both DEX implant groups compared with sham (P<0.001). The percentage of eyes with a > or =15-letter improvement in BCVA was significantly higher in both DEX implant groups compared with sham at days 30 to 90 (P<0.001). The percentage of eyes with a > or =15-letter loss in BCVA was significantly lower in the DEX implant 0.7-mg group compared with sham at all follow-up visits (P< or =0.036). Improvement in mean BCVA was greater in both DEX implant groups compared with sham at all follow-up visits (P< or =0.006). Improvements in BCVA with DEX implant were seen in patients with BRVO and patients with CRVO, although the patterns of response differed. The percentage of DEX implant-treated eyes with intraocular pressure (IOP) of > or =25 mmHg peaked at 16% at day 60 (both doses) and was not different from sham by day 180. There was no significant between-group difference in the occurrence of cataract or cataract surgery.

CONCLUSIONS

Dexamethasone intravitreal implant can both reduce the risk of vision loss and improve the speed and incidence of visual improvement in eyes with ME secondary to BRVO or CRVO and may be a useful therapeutic option for eyes with these conditions.

Long-term follow-up of OCT-guided bevacizumab treatment of macular edema due to retinal vein occlusion

BACKGROUND

To evaluate the long-term outcome of an OCT-guided reinjection scheme for bevacizumab treatment of macular edema (ME) due to retinal vein occlusion.

METHODS

Patients with persistent ME (>250 microm) due to central retinal vein occlusion (CRVO) or branch retinal vein occlusion (BRVO) received intravitreal bevacizumab 2.5 mg/0.1 ml. Visual acuity (ETDRS), ophthalmic examination and OCT were performed at baseline and at 6- to 8-week intervals. Reinjections were only performed if OCT showed persistent or recurrent ME.

RESULTS

Sixty-one patients with a minimum follow-up of 25 weeks were included in this analysis. Mean follow-up was 60 +/- 29 wks. In CRVO patients, central retinal thickness (CRT) decreased from 748 +/- 265 microm to 372 +/- 224 microm (p < 0.001) and visual acuity (VA) improved by 1.9 +/- 3.2 lines. In BRVO patients, mean CRT decreased from 601 +/- 206 microm to 386 +/- 178 microm (p < 0.001) and VA improved by 1.8 +/- 2.6 lines. Thirty-three percent of CRVO and 15% of BRVO patients did not show a ME recurrence for > or =25 wks at last visit. Thirty-seven percent of CRVO and 50% of BRVO patients suffered recurrences of ME within the last 25 wks, whereas 30% of CRVO and 35% of BRVO patients did not achieve a complete resolution of ME at any follow-up visit after receiving a minimum of three injections. CRVO patients with dry interval of > or =25 weeks at last visit were significantly younger, had a thinner CRT at baseline and more often had a complete resolution of ME after the first injection. In CRVO and BRVO, final VA was correlated significantly with initial VA, patients' age and final CRT. Change of VA was correlated with change of CRT in BRVO.

CONCLUSIONS

Patients with retinal vein occlusion benefit from treatment with bevacizumab. Favourable long-term results without necessity of further injections were achieved in 33% and 15% of CRVO and BRVO patients respectively. The remaining patients needed repeated injections to treat ME recurrences. However, one third of the CRVO/BRVO patients did not improve in VA, and further injections might be discontinued in these patients.

Intravitreal ranibizumab (Lucentis) for treatment of central retinal vein occlusion: a prospective study

BACKGROUND/PURPOSE

To evaluate the effect of individualized repeated intravitreal injections of ranibizumab (Lucentis) on visual acuity (VA) and central foveal thickness (CFT) for central retinal vein occlusion (CRVO)-induced macular edema.

METHODS

Our study was a prospective interventional case series. Twelve eyes of 12 consecutive patients diagnosed with CRVO-related macular edema (nine perfused, three ischemic CRVO) treated with repeated (when CFT was >220 microm) intravitreal injections of ranibizumab as a monotherapy within 3 months of onset were evaluated. Optical coherence tomography (OCT) and fluorescein angiography (FA) were performed monthly and every 3 months respectively. Changes in VA (ETDRS) and CFT were analyzed using the student's paired t-test.

RESULTS

The mean time from diagnosis until injection was 80 days (2.7 months; range, 63-90 days) and the follow-up time was 12 months. In total, 89 injections were performed (mean 7.4). The mean CFT improved from 480 +/- 166 microm at baseline to 230 +/- 33 microm (P < 0.001) at the end of the follow-up. During the same period, of the 12 eyes, eight demonstrated improved VA (>0.3 LogMAR change, >15 letters), three stable VA and one worse VA as compared to baseline. None of the nine patients with perfused CRVO were converted to ischemic at 12 months, and one of the three eyes with ischemic CRVO developed iris neovascularization despite two ranibizumab injections. No ocular or systemic side-effects were noted.

CONCLUSION

Individualized repeated intravitreal injections of ranibizumab have shown promising results in VA improvement and decrease in CFT in patients with macular edema associated with CRVO. Further studies are needed in order to elucidate the role of intravitreal lucentis in the ischemic form of CRVO, and its efficacy in preventing conversion from the perfused to the ischemic form of the disease.

Intravitreal steroids versus observation for macular edema secondary to central retinal vein occlusion

BACKGROUND

Central retinal vein occlusion (CRVO) is a common retinal vascular abnormality associated with conditions such as hypertension, diabetes, glaucoma, and a wide variety of hematologic disorders. Macular edema (ME) represents an important vision-threatening complication of CRVO. There is no proven treatment; laser photocoagulation is not effective in treating cystoid macular edema secondary to CRVO. Intravitreal steroids, such as triamcinolone acetonide, have been utilized to treat macular edema stemming from a variety of etiologies and may represent a treatment option for CRVO-ME.

OBJECTIVES

The objective of this review was to explore the effectiveness and safety of intravitreal steroids in the treatment of CRVO-ME.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 4, 2008), MEDLINE (January 1950 to November 2008) and EMBASE (January 1980 to November 2008). There were no language or date restrictions in the search for trials. The electronic databases were last searched on 5 November 2008. For all included primary studies, we used The Science Citation Index and manually reviewed reference lists to identify other possible relevant trials. We contacted researchers in the field, currently working on a randomized controlled trial (RCT) on this topic (The Standard Care versus Corticosteroid for Retinal Vein Occlusion - SCORE study), for information on additional current, past, or unpublished trials.

SELECTION CRITERIA

We considered RCTs that compared intravitreal steroids of any dosage/duration to observation in the treatment of CRVO-ME for inclusion in this review. We focused on studies that included individuals of any age or gender with unilateral or bilateral disease, with a minimum of six months follow up. Secondarily we considered non-randomized studies with the same criteria for description of evidence, however we did not conduct a separate electronic search for finding all non-randomized studies.

DATA COLLECTION AND ANALYSIS

We found no RCTs that met the inclusion criteria after independent and duplicate review of the search results.

MAIN RESULTS

We found no relevant RCTs and therefore performed no meta-analysis. Evidence from non-randomized studies is reported in this review.

AUTHORS' CONCLUSIONS

There is inadequate evidence for the use of intravitreal steroids for CRVO-ME due to a paucity of RCTs and well-designed observational studies on the topic; therefore, it is still an experimental procedure.

Use of intravitreal triamcinolone in the treatment of macular edema related to retinal vein occlusion

Objective:

To analyze the increasing trend of intravitreal triamcinolone (IVTA) use in the treatment of retinal vein occlusion-related macular edema.

Methods:

We performed MEDLINE/PUBMED searches (September 1984 - December 2007) to identify articles containing the keywords macular edema and triamcinolone. Case reports, reviews and abstracts were identified from references in the reviewed literature. This review focuses on literature published during the past 7 years with more than two-thirds of the articles that we reviewed being printed during the past 5 years. These reports analyzed the success of IVTA in the treatment of macular edema over a 12 month course of time.

Results:

The majority of studies suggested promising results for short time periods (4-6 months) after IVTA treatments. However, long term results were not encouraging.

Conclusions:

The success of IVTA therapy for short durations has been the impetus for development of sustained release devices to be used in the treatment of macular edema associated with various retinal diseases including edema related to retinal vein occlusion.

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.

RETINAL TOXICITY OF INTRAVITREAL KENALOG IN ALBINO RABBITS

PURPOSE

To evaluate possible toxicity of intravitreal Kenalog (commercial triamcinolone acetonide) to the retina of albino rabbits.

METHODS

Forty-three albino rabbits were injected intravitreally with 0.1 mL of experimental solution to the right eye and 0.1 mL of saline to the left eye (control). Rabbits in Group A (n=28) were injected with 4 mg/0.1 mL of Kenalog suspension; rabbits in Group B (n=8) were injected with 0.1 mL of Kenalog vehicle; and rabbits in Group C (n=7) were injected with 4 mg/0.1 mL of triamcinolone acetonide. Rabbits were examined ophthalmoscopically and by electroretinogram (ERG) recordings before and at different time intervals after injection. At the end of follow-up, animals were killed and the retinas were prepared for light microscopy.

RESULTS

Thirty-eight rabbits completed 4 weeks of follow-up. Follow-up for 8 and 17 weeks was completed by 29 and 3 rabbits, respectively. Intravitreal commercial Kenalog or its vehicle alone caused approximately 50% reduction in the ERG b-wave amplitude at the end of follow-up. Pure triamcinolone acetonide caused only mild (up to 14%) reduction of the ERG b-wave amplitude. Histologic examination of retinas exposed to Kenalog or its vehicle showed severe damage to all retinal layers in areas close to the site of Kenalog injection.

CONCLUSIONS

Intravitreal injection of 4 mg Kenalog suspension is retinotoxic to albino rabbit eyes. The vehicle of Kenalog is probably the main cause of this toxicity.

Evaluation of Intravitreal Kenalog Toxicity in Humans

OBJECTIVE

To evaluate possible functional toxicity of intravitreal Kenalog (commercial triamcinolone acetonide) in patients' retinas.

DESIGN

Observational case series.

PARTICIPANTS

Thirty-two phakic eyes of 16 patients who had nonproliferative diabetic retinopathy and bilateral macular edema refractory to laser therapy, which had no other eye disorder and no previous ophthalmic operation.

INTERVENTION

Kenalog (4 mg/0.1 ml) was injected intravitreally to one eye, whereas the second eye served as the control. The experimental eye was chosen as the eye with worse visual acuity (VA).

MAIN OUTCOME MEASURES

Deterioration of electroretinogram parameters of the study eye measured at 3 months of follow-up when compared with the electroretinogram responses of the fellow, control eye and when compared with electroretinogram responses obtained before injection. Visual acuity, intraocular pressure (IOP), and eventual complications were assessed. No improvement or deterioration of VA or any increase in IOP was regarded as a secondary outcome.

RESULTS

Average maximal response amplitude ratios of the dark-adapted b-wave (treated/control eyes) of the electroretinogram were 0.93 before (P = 0.221) and 0.94 (P = 0.387) 3 months after Kenalog injection. Average ratios of the light-adapted b-wave amplitude (treated/control eyes) of the electroretinogram were 1.04 (P = 0.702) before and 0.86 (P = 0.138) 3 months after Kenalog injection. No significant differences (P>0.05) were found between the electroretinogram parameters obtained from all eyes before and 3 months after Kenalog injection. Average VAs in the treated eyes were 1.08, 0.8, and 1.0 logarithm of the minimum angle of resolution units before and 2 and 4 months after injection, respectively. Temporary elevation of IOP was found in 4 treated eyes of 4 patients (25%).

CONCLUSIONS

No electroretinographic evidence of a retinotoxic effect of intravitreal Kenalog was found in our patients.

Interventions for Central Retinal Vein Occlusion

TOPIC

To assess the evidence for the effectiveness of interventions to improve visual acuity (VA) and prevent or treat neovascularization secondary to central retinal vein occlusion (CRVO).

CLINICAL RELEVANCE

Central retinal vein occlusion is a common cause of visual morbidity and blindness. Many different interventions have been advocated, but the evidence justifying their use remains unclear.

METHODS/LITERATURE REVIEWED

English and non-English language articles were retrieved using a keyword search of Medline (1966 onwards), Embase, the Cochrane Collaboration, the National Institutes of Health Clinical Trials database, and the Association for Research in Vision and Ophthalmology (2003-2005). This was supplemented by manually searching references of review articles. Two investigators independently identified all randomized clinical trials (RCTs) on interventions in CRVO with more than 3 months' follow-up.

RESULTS

Of 4133 citations retrieved, 17 RCTs comparing intervention with a control group were identified. There were 4 RCTs on laser photocoagulation. Grid macular laser photocoagulation did not improve VA in CRVO with macular edema. Prophylactic panretinal photocoagulation did not prevent angle and iris neovascularization in ischemic CRVO, but resulted in regression of angle and iris neovascularization and reduced progression to neovascular glaucoma. There were 4 RCTs that reported improvement in VA with inpatient hemodilution, 2 RCTs with no significant improvement, and 1 RCT showing deterioration in VA after outpatient hemodilution. Randomized clinical trials evaluating ticlodipine, troxerutin, and streptokinase showed a limited or no benefit.

CONCLUSIONS

This review found limited level I evidence for any intervention to improve VA in patients with CRVO. Panretinal photocoagulation resulted in regression of neovascularization. Hemodilution may improve vision in some patients, but the data conflict. More robust randomized controlled trials evaluating current treatments for CRVO are needed. The results of ongoing RCTs on intravitreal triamcinolone, anti-vascular endothelial growth factor agents, and chorioretinal anastomosis are awaited with interest.

Intravitreal triamcinolone acetonide: a change in a paradigm

BACKGROUND

Based on experimental studies and clinical observations by Robert Machemer, Gholam Peyman and others, the vitreous cavity has increasingly been used as a reservoir of drugs for the direct treatment of intraocular diseases.

METHODS AND RESULTS

The most widely injected drug so far has been triamcinolone acetonide for various intraocular neovascular and edematous diseases. Comparing the various diseases with respect to effect and side effects of the treatment, the best response in terms of gain in visual acuity has been achieved for intraretinal edematous diseases such as diffuse diabetic macular edema, branch retinal vein occlusion, central retinal vein occlusion, and pseudophakic cystoid macular edema. In eyes with various types of noninfectious uveitis including acute or chronic sympathetic ophthalmia and Adamantiadis-Behçet's disease, visual acuity increased and the degree of intraocular inflammation decreased. Some studies have suggested that intra- vitreal triamcinolone may be useful as an angiostatic agent in eyes with iris neovascularization and proliferative ischemic retinopathies. Intravitreal triamcinolone may possibly be helpful as adjunct therapy for exudative age-related macular degeneration, particularly in combination with photodynamic therapy. In eyes with chronic, therapy-resistant ocular hypotony, intravitreal triamcinolone can induce an increase in intraocular pressure and may stabilize the eye. The complications of intravitreal triamcinolone therapy include secondary ocular hypertension in about 40% of the eyes injected; medically uncontrollable high intraocular pressure leading to antiglaucomatous surgery in about 1-2% of the eyes; posterior subcapsular cataract and nuclear cataract leading to cataract surgery in about 15-20% in elderly patients within 1 year after injection; postoperative infectious endophthalmitis with a rate of about 1:1,000; noninfectious endophthalmitis, perhaps due to a reaction to the solvent agent, and pseudoendophthalmitis with triamcinolone acetonide crystals appearing in the anterior chamber. Intravitreal triamcinolone injection can be combined with other types of intraocular surgery including cataract surgery, particularly in eyes with iris neovascularization. Cataract surgery performed some months after the injection does not show a markedly elevated complication rate. The injection may be repeated, if vision redecreases. In nonvitrectomized eyes, the duration of the effect and side effects of a single intravitreal injection of triamcinolone is about 6-9 months for a dosage of about 20 mg, and about 2-4 months for a dosage of 4 mg. It has remained unclear so far, whether and how to remove the solvent agent. In the future, intravitreal triamcinolone may be combined with other antiangiogenic drugs for the treatment of exudative age-related macular degeneration or with neuroprotective drugs for treatment of diabetic retinopathy.

CONCLUSIONS

Despite an exponentially increasing number of mostly case-series studies, the intravitreal injection of triamcinolone may still be considered an experimental procedure until randomized studies have been presented.

Intravitreal triamcinolone acetonide for treatment of intraocular oedematous and neovascular diseases

Intravitreal triamcinolone acetonide (IVTA) has increasingly been applied as treatment for various intraocular neovascular and oedematous diseases. Comparing the various diseases with respect to effect and side-effects of the treatment, the best response in terms of gain in visual acuity (VA) has been achieved for intraretinal oedematous diseases such as diffuse diabetic macular oedema, branch retinal vein occlusion, central retinal vein occlusion and pseudophakic cystoid macular oedema. In eyes with various types of non-infectious uveitis, including acute or chronic sympathetic ophthalmia and Adamantiadis-Behcet's disease, VA increased and the degree of intraocular inflammation decreased. Some studies have suggested that intravitreal triamcinolone may be useful as angiostatic therapy in eyes with iris neovascularization and proliferative ischaemic retinopathies. Intravitreal triamcinolone may possibly be helpful as adjunct therapy for exudative age-related macular degeneration (AMD), particularly in combination with photodynamic therapy. In eyes with chronic, therapy-resistant ocular hypotony, intravitreal triamcinolone can induce an increase in intraocular pressure (IOP) and may stabilize the eye. The complications of intravitreal triamcinolone therapy include: secondary ocular hypertension in about 40% of the eyes injected; medically uncontrollable high IOP leading to antiglaucomatous surgery in about 1-2% of the eyes; posterior subcapsular cataract and nuclear cataract leading to cataract surgery in about 15-20% of elderly patients within 1 year of injection; postoperative infectious endophthalmitis occurring at a rate of about one per 1000; non-infectious endophthalmitis, perhaps due to a reaction to the solvent agent, and pseudo-endophthalmitis with triamcinolone acetonide crystals appearing in the anterior chamber. Intravitreal triamcinolone injection can be combined with other intraocular surgeries, including cataract surgery, particularly in eyes with iris neovascularization. Cataract surgery performed some months after the injection does not show a markedly elevated complication rate. The injection may be repeated if the resultant benefits decrease after the initial IVTA injection. In non-vitrectomized eyes, the duration of the effect and side-effects of a single intravitreal injection of triamcinolone is about 6-9 months for a dosage of about 20 mg, and about 2-4 months for a dosage of 4 mg. So far, it has remained unclear whether the solvent agent should be removed, and if so, how.