INTRAVITREAL TRIAMCINOLONE TREATMENT FOR MACULAR EDEMA ASSOCIATED WITH CENTRAL RETINAL VEIN OCCLUSION AND HEMIRETINAL VEIN OCCLUSION

The Effect of Intracameral Triamcinolone Acetonide on Controlling Common Complications following Phacoemulsification in Dogs

The intracameral injection of triamcinolone acetonide (TA) has achieved favorable clinical effects in controlling intraocular inflammatory reactions in humans after cataract surgery. However, the effect of this method remains unclear in veterinary practice. In this paper, 18 dogs with bilateral cataracts were randomly divided into three groups, with 6 dogs in each group. Phacoemulsification and intraocular lens implantation were performed on the 36 eyes of these dogs. A total of 0.1 mL of TA solution was injected into the oculus dexter (OD) anterior chambers. All oculus sinister (OS) anterior chambers of these dogs were used as controls. The results demonstrated that the corneal edema severity scores of the OD (1.5 mg TA) were lower than those of the OS from the 1st to 7th day after surgery, with a significant difference on the 3rd day after surgery (p = 0.033). The corneal edema severity scores in the OD (1.5 mg TA) were significantly lower than those in the OD (0.5 mg TA) on the 3rd day after surgery (p = 0.036). The aqueous humor protein concentration of the OD (1.5 mg TA) had a lower concentration than the OS on the 1st day after surgery (p = 0.004). Furthermore, on the 5th and 10th days, the aqueous humor protein concentration of the OD (1.5 mg TA) was lower than that of the OS (p = 0.038 and p = 0.044, respectively). The aqueous humor PGE2 concentration of the OD (1.5 mg TA) had a lower concentration than the OS on the 1st day after surgery (p = 0.026). The aqueous humor PGE2 concentrations in the OD (1.0 mg TA) and OD (1.5 mg TA) were lower compared to that in the OD (0.5 mg TA) on the 1st day after surgery (p = 0.041 and p = 0.037, respectively). It was demonstrated that TA-based treatment can be safely employed to effectively control common complications after phacoemulsification in dogs.

SCORE2 Report 24: Nonlinear Relationship of Retinal Thickness and Visual Acuity in Central Retinal and Hemiretinal Vein Occlusion

PURPOSE

To investigate whether a nonlinear association between central subfield thickness (CST) on spectral-domain OCT and concurrent visual acuity letter score (VALS) exists in eyes treated initially with aflibercept or bevacizumab for macular edema associated with central retinal vein occlusion (CRVO) or hemiretinal vein occlusion (HRVO) in the Study of Comparative Treatments for Retinal Vein Occlusion 2 (SCORE2).

DESIGN

Long-term follow-up after a randomized clinical trial from 64 centers in the United States.

PARTICIPANTS

Participants were followed up to 60 months and treated at investigator discretion after completing the 12-month treatment protocol.

METHODS

Two-segment linear regression models were compared with simple linear regression models of VALS on CST. Pearson correlation coefficients were calculated to assess strength of CST and VALS associations.

MAIN OUTCOME MEASURES

Central subfield thickness was measured by OCT and VALS by the electronic Early Treatment Diabetic Retinopathy Study methodology.

RESULTS

Estimated inflection points, reflecting turning points at which the CST and VALS association changes from positive to negative, calculated at 7 postbaseline visits, range from 217 to 256 μm. A strongly positive correlation exists to the left of each estimated inflection point, ranging from 0.29 (P < 0.01 at month 60) to 0.50 (P < 0.01 at month 12), and a strongly negative correlation exists to the right of each estimated inflection point, ranging from -0.43 (P < 0.01 at month 1) to -0.74 (P < 0.01 at month 24). Randomization statistical tests showed that 2-segment models are favored over 1-segment models for all postbaseline months (P < 0.001 for all tests performed).

CONCLUSIONS

The relationship between CST and VALS in eyes with CRVO or HRVO after treatment with anti-vascular endothelial growth factor (VEGF) therapy is not simply linear. The usually modest correlations between OCT-measured CST and visual acuity belie strong left and right correlations present in 2-segment models. Post-treatment CST close to the estimated inflection points showed the best expected VALS. The SCORE2 participants with a post-treatment CST after treatment close to the estimated inflection points of 217 to 256 μm showed the best VALS. In patients treated with anti-VEGF for macular edema associated with CRVO or HRVO, a thinner retina is not always associated with better VALS.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

COMBINED TREATMENT WITH BEVACIZUMAB AND TRIAMCINOLONE ACETONIDE FOR MACULAR EDEMA DUE TO RETINAL VEIN OCCLUSION

The purpose of this study was to determine the efficacy of combined intravitreal bevacizumab and triamcinolone in the treatment of macular edema due to retinal vein occlusion. A prospective randomized trial was conducted in the Department of Ophthalmology, Osijek University Hospital Centre in Osijek including 51 patients divided into three groups depending on the drug received. The first group received 1.25 mg intravitreal bevacizumab, the second group received 1 mg intravitreal triamcinolone, and the third group received a combination of 1.25 mg bevacizumab and 1 mg intravitreal triamcinolone on the same day. Changes in the central macular thickness, intraocular pressure and visual acuity were monitored during the follow up period. The retinal perfusion status was evaluated by fluorescein angiography. The group that received combined treatment had better outcome in terms of reduction of macular thickness. There was no statistically significant intraocular pressure elevation among the three treatment groups or within each group of patients. A positive trend regarding visual improvement was observed in the group receiving combined treatment in spite of the lowest initial visual acuity, highest value of macular thickness and longest mean duration of symptoms. In conclusion, combined treatment with bevacizumab and triamcinolone for the treatment of retinal vein occlusion is more potent, safe, efficient and cost-effective. It can also be recommended because fewer injections are needed in patients undergoing treatment for macular edema.

Comparison of the efficacy and safety of drug therapies for macular edema secondary to central retinal vein occlusion

OBJECTIVES

To evaluate the efficacy and safety of anti-vascular endothelial growth factor (VEGF) agents and corticosteroids for the treatment of macular oedema (ME) secondary to central retinal vein occlusion (CRVO).

DESIGN

Systematic review and network meta-analysis.

PARTICIPANTS

Patients from previously reported randomised controlled trials (RCTs) comparing anti-VEGF and corticosteroids for the treatment of ME secondary to CRVO.

METHODS

Literature searches were conducted using PubMed, Medline, Embase, Cochrane Library and clinicaltrials.gov until March 2017. Therapeutic effects were estimated using the proportions of patients gaining/losing ≥15 letters, best-corrected visual acuity (BCVA) and central retinal thickness (CRT). Treatment safety was estimated using the proportions of adverse events, namely increased intraocular pressure (IOP), cataracts, vitreous haemorrhage (VH) and retinal tear. The software ADDIS (V.1.16.8) was used for analysis. Treatment effect and safety of different drugs could be ranked based on simulation.

RESULTS

Eleven RCTs comprising 2060 patients were identified. Regarding patients gaining ≥15 letters, aflibercept and ranibizumab were significantly more effective than sham/placebo at 6 months. Regarding patients losing ≥15 letters at 6 months, ranibizumab showed significant improvement compared with dexamethasone. Aflibercept, bevacizumab or ranibizumab showed greater improvements in BCVA than sham/placebo at 6 months. Intravitreal ranibizumab injection demonstrated greater CRT reduction than both sham and dexamethasone did. Dexamethasone had a higher risk of increased IOP than aflibercept and ranibizumab. Ranibizumab demonstrated a greater risk of cataracts than dexamethasone. Aflibercept and ranibizumab demonstrated low incidence of VH and retinal tear, respectively. Aflibercept had a slight advantage over ranibizumab as assessed by benefit-risk analysis.

CONCLUSIONS

Anti-VEGF agents have advantages in the treatment of ME secondary to CRVO. Aflibercept and ranibizumab showed marked BCVA improvement and CRT reduction. Aflibercept may have a slight advantage over ranibizumab. The results of this study can serve as a reference for clinicians to provide patient-tailored treatment.

PROSPERO REGISTRATION NUMBER

CRD42017064076.

Comparison between intravitreal bevacizumab and posterior sub-tenon injection of triamcinolone acetonide in macular edema secondary to retinal vein occlusion

Aim

To compare the efficacy and safety between posterior sub-tenon injection of triamcinolone acetonide (PSTA) and intravitreal injection of bevacizumab (Avastin) (IVIA) in the treatment of macular edema secondary to retinal vein occlusion.

Patients and methods

A total of 45 eyes were retrospectively enrolled (23 eyes with intravitreal bevacizumab and 22 eyes with posterior sub-tenon triamcinolone acetonide). Main endpoints included logMAR of best-corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure (IOP) before and after treatment at 6 months.

Results

The mean logMAR improved from 0.78 to 0.56 at 6 months for intravitreal bevacizumab (p=0.001), and from 0.91 to 0.79 and 0.87 at 3 and 6 months (p=0.038 and 0.13), respectively, for sub-tenon triamcinolone acetonide. At 6 months, the BCVA was significantly better in the bevacizumab group (p=0.02). Both groups' mean CMT significantly improved, from 478 µm at baseline to 295 µm at 6 months in IVIA group (p<0.001) and from 419 µm at baseline to 350 µm in PSTA group (p=0.012); however, this was not different between the groups at 6 months (p=0.065). Recurrence of macular edema was not different between the groups either (p=0.08). Poorer final vision was associated with poorer baseline BCVA and diagnosis of central retinal vein occlusion after adjustment for age and sex (p<0.001 and 0.012, respectively). Significant elevation of IOP was noted at 3 months in the PSTA group, but declined at 6 months compared with baseline (p=0.002 and 0.41, respectively).

Conclusion

Intravitreal bevacizumab seemed to achieve better visual acuity compared with posterior sub-tenon injections of triamcinolone acetonide at 6 months, while CMT was comparable. PSTA still resulted in transient IOP elevation.

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.

Vision Preservation in Eyes of Polypoidal Choroidal Vasculopathy with Low-Dose Intravitreal Triamcinolone Acetonide

PURPOSE

To evaluate the efficacy and adverse effects of using low-dose intravitreal triamcinolone acetonide (IVTA) to preserve vision in polypoidal choroidal vasculopathy (PCV) eyes.

METHODS

This retrospective chart review study examined 8 eyes of 7 PCV patients, for whom verteporfin photodynamic therapy (vPDT) or antivascular endothelial growth factor (VEGF) therapy was not affordable/available and also with intolerable risk because of underlying cardiovascular and/or cerebrovascular ischemia. Low-dose IVTA (1 mg/0.025 mL) monotherapy was administered and repeated every 4 weeks if intraretinal edema or subretinal fluid persisted.

RESULTS

The median follow-up time was 26.4 months. Three eyes (3/8) maintained their initial best-corrected visual acuity and 4 eyes (4/8) exhibited improvement, whereas 1 eye (1/8) sustained some loss. The mean injection number per month was 0.7 for the first 6 months, after which it decreased to 0.4. In regard to adverse effects, intraocular pressure (IOP) of more than 21 mmHg was noted as persisting for a few weeks in 4 eyes and that of more than 30 mmHg was noted once in 1 eye. The increased IOP was adequately controlled by using IOP-lowering agents. Two initially phakic eyes each underwent cataract surgery in the 12th and 14th months after treatment.

CONCLUSIONS

Low-dose IVTA therapy may be valuable for preserving the vision of PCV patients, while vPDT or anti-VEGF is not affordable/available or of those with underlying diseases for whom anti-VEGF therapy is with intolerable risk.

Differential flow rate of commercially available triamcinolone with and without preservative through small-gauge needles

OBJECTIVE

To compare the flow rate through different gauge needles of triamcinolone acetonide with benzyl alcohol (TABA) versus preservative-free triamcinolone acetonide injectable suspension (TAIS).

MATERIALS AND METHODS

Experimental injections of 1 mL of TABA or TAIS were performed through a 27-, 30-, or 32-gauge needle. A piezoelectric pressure transducer connected to a personal computer was placed between the syringe and needle to record the force-time relationship and assess the flow rate (mL/s). Measurements were performed in triplicate.

RESULTS

Flow rates were similar between preparations using a 27-gauge needle. Using a 30-gauge needle, the flow rate was 0.058 mL/s for TABA and 0.178 mL/s for TAIS. Using a 32-gauge needle, no flow was sustained by TABA, whereas the flow rate of TAIS was 0.114 mL/s (P < .05).

CONCLUSION

TAIS can be injected through a 32-gauge needle without the risk of obstruction. Occlusions were seen with TABA using the 30- and 32-gauge needles.

Safety of intravitreal triamcinolone acetonide: an electrophysiologic and histopathological study in rabbits

AIM

To evaluate the retinal safety of various doses of intravitreal triamcinolone acetonide (TA) in rabbits.

METHODS

Thirty New Zealand albino rabbits were divided into five groups (six animals each). In group 1 (control group), each animal received a single intravitreal injection of 0.1mL phosphate buffered saline. In groups 2, 3, 4 and 5, each rabbit received a single intravitreal injection of 4, 8, 16 and 32mg of TA, respectively. Each dose was contained in 0.1mL phosphate buffered saline. Clinical ocular examinations were performed before the injection and on the 1st, 3rd, 10th and 17th post-injection days. A standard dark adapted electroretinogram (ERG) was obtained before injection and on the 3rd, 10th and 17th post-injection days. After 17d, animals were sacrificed and their eyes prepared for pathological examination.

RESULTS

By monitoring ERG as a functional index for the retina, intravitreal injection of 4mg TA showed no significant ERG changes. At doses of 8, 16 and 32, hyper-abnormal responses in a- and b- waves of ERG were detected on the 3rd post-injection day. These changes gradually returned back to normal limits after 17d. Histopathological examination of the retina of all animals showed no pathological changes.

CONCLUSION

High doses of intravitreal TA seemed to have enhancing effects on the retinal function with gradual return to normal limits with no pathological changes detected in examined eyes.

Evaluation of contrast sensitivity after single intravitreal triamcinolone injection for macular edema secondary to branch retinal vein occlusion

Purpose. To evaluate visual acuity (VA), contrast sensitivity (CS), and central retinal thickness (CRT) after intravitreal triamcinolone acetonide (IVT) injection for macular edema secondary to branch retinal vein occlusion (BRVO). Methods. In this prospective study, a total of 21 eyes of 21 patients were included. VA, CS, and CRT were assessed at baseline and at 1, 3, and 6 months after a single IVT injection. Results. Mean age was 64.57 ± 8.34 years. The mean baseline VA (LogMAR) increased from 1.11 ± 0.63 to 0.55 ± 0.39 (P < 0.001), 0.60 ± 0.40 (P < 0.001), and 0.78 ± 0.39 (P = 0.07) at 1, 3, and 6 months, respectively. The mean baseline CS (log CS) at 1 meter improved from 0.66 ± 0.49 to 1.11 ± 0.32 (P < 0.001), 0.99 ± 0.38 (P < 0.001), and 0.72 ± 0.37 (P = 0.8) at 1, 3, and 6 months, respectively. The mean baseline CS (log CS) at 3 meters improved from 0.34 ± 0.41 to 0.74 ± 0.41 (P < 0.001), 0.64 ± 0.44 (P = 0.036), and 0.46 ± 0.49 (P = 0.8) at 1, 3, and 6 months, respectively. The mean baseline CRT decreased from 511 ± 146 μm to 242 ± 119 μm, 277 ± 131 μm, and 402 ± 166 μm at 1, 3, and 6 months after IVT (P < 0.001 for each). Conclusion. Single IVT injection improved VA and CS and reduced CRT at 1 and 3 months of treatment. VA and CS returned to baseline levels at 6 months.

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.

Bevacizumab for macular edema secondary to retinal vein occlusion: a systematic review and meta-analysis

PURPOSE

To assess the effect and safety of using single intravitreal bevacizumab (IVB) versus intravitreal triamcinolone acetonide (IVTA) and grid laser photocoagulation (GLP), or a combination of IVB and IVTA for treatment of retinal vein occlusion (RVO)-associated macular edema, mainly exploring its effects on visual acuity (VA) and central macular thickness (CMT).

METHODS

Eligible studies were identified via searching databases, including Medline (PubMed), Web of Science, and the Cochrane Library, without status or other limits up to June 2012.

SELECTION CRITERIA

We include randomized clinical control trials comparing 1.25 mg IVB injection with other treatment strategies, including a 4 mg IVTA injection or GLP or a combination of 1.25 mg IVB and 2 mg IVTA injection, for patients with RVO-associated macular edema. Eligible studies should report both VA and CMT outcomes, and with a minimum follow-up of 4 weeks. Results: Two authors assessed the trial quality and extracted data independently.

MAIN RESULTS

Four studies were included in this study. Comparing to IVTA and GLP, IVB was more effective in improving VA at 1 month (weighted mean difference [WMD], -0.07; 95% confidence interval [CI], -0.10 to -0.05; P<0.00001), 3 months (WMD, -0.24; 95% CI, -0.28 to -0.20; P<0.00001), and 6 months during the follow-up (WMD, -0.17; 95% CI, -0.21 to -0.13; P<0.00001) in patients with RVO-associated macular edema. There was no statistical significance in reducing CMT values throughout the periods. Compared with IVB/IVTA combination, VA improvement became statistically significant at 3 months of follow-up (WMD, -0.26; 95% CI, -0.29 to -0.23; P<0.00001), while no statistical significance was found in both VA values at 1 month of follow-up and CMT values throughout the periods. The occurrence of intraocular pressure (IOP) was much lower in IVB groups.

CONCLUSIONS

IVB is effective in treating patients with RVO-associated macular edema; especially if it has distinct effects, of which, VA could be improved to the utmost extent as well as by the earliest of time. IVB is also effective in decreasing CMT, but without any significant advantages over IVTA or GLP. Furthermore, IVB seems to be safer than IVTA in consideration of IOP increase.

Personalized Medicine in Ophthalmology: From Pharmacogenetic Biomarkers to Therapeutic and Dosage Optimization

Rapid progress in genomics and nanotechnology continue to advance our approach to patient care, from diagnosis and prognosis, to targeting and personalization of therapeutics. However, the clinical application of molecular diagnostics in ophthalmology has been limited even though there have been demonstrations of disease risk and pharmacogenetic associations. There is a high clinical need for therapeutic personalization and dosage optimization in ophthalmology and may be the focus of individualized medicine in this specialty. In several retinal conditions, such as age-related macular degeneration, diabetic macular edema, retinal vein occlusion and pre-threshold retinopathy of prematurity, anti-vascular endothelial growth factor therapeutics have resulted in enhanced outcomes. In glaucoma, recent advances in cytoskeletal agents and prostaglandin molecules that affect outflow and remodel the trabecular meshwork have demonstrated improved intraocular pressure control. Application of recent developments in nanoemulsion and polymeric micelle for targeted delivery and drug release are models of dosage optimization, increasing efficacy and improving outcomes in these major eye diseases.

Influence of drug lipophilicity on drug release from sclera after iontophoretic delivery of mixed micellar carrier system to human sclera

Mixed micelles prepared using sodium taurocholate (TA) and egg lecithin (LE) were previously found to be an effective carrier for sustained release of a poorly water-soluble drug in transscleral iontophoretic delivery. The objectives of the present study were to investigate the effects of drug lipophilicity upon micellar carrier solubilization potential and drug release profiles from the sclera after iontophoretic delivery of model lipophilic drugs dexamethasone (DEX), triamcinolone acetonide (TRIAM), and β-estradiol (E2β) with a mixed micellar carrier system of TA-LE (1:1 mole ratio). In this study, the micellar carrier system was characterized for drug solubilization. The micelles encapsulating these drugs were evaluated for transscleral passive and 2-mA iontophoretic delivery (both cathodal and anodal) and drug release from excised human sclera in vitro. The results show that drug solubility enhancement of the micellar carrier system increased with increasing drug lipophilicity. The more lipophilic drugs E2β and TRIAM displayed slower drug release from the sclera compared with the less lipophilic drug DEX after iontophoretic drug delivery with the mixed micelles. These results suggest that the combination of transscleral iontophoresis and micellar carriers is more effective in sustaining transscleral delivery of the more lipophilic drugs studied in this investigation.

A comparison of three different intravitreal treatment modalities of macular edema due to branch retinal vein occlusion

PURPOSE

To compare the efficacy of intravitreal injection of triamcinolone, bevacizumab, and a combination of triamcinolone-bevacizumab for the management of macular edema due to branch retinal vein occlusion.

METHODS

Fifty-two eyes of 52 patients (29 male, 23 female) with branch retinal vein occlusion and macular edema were included. Patients received one of the following intravitreal treatments: 4 mg triamcinolone acetonide monotherapy (n=17), 1.25 mg bevacizumab monotherapy (n=14) or a combination of 2 mg triamcinolone acetonide and 1.25 mg bevacizumab (n=21). Measurements of Snellen visual acuity and central macular thickness with optical coherence tomography were done at baseline, and at months one, three, and six.

RESULTS

At baseline, the three groups did not differ in age (P=0.12), duration of macular edema (P=0.24), visual acuity (P=0.62), central macular thickness (P=0.16), and intraocular pressure (P=0.15). All study groups showed significant reduction of central macular thickness (P=0.02, P=0.02, and P=0.001, respectively) and improvement in visual acuity (P=0.02, P= 0.02 and P=0.02, respectively) one month after injection. At six months, there was a significant reduction in central macular thickness (P=0.02, P=0.02, and P=0.04, respectively) while only bevacizumab monotherapy group demonstrated significant improvement in visual acuity (P=0.01).

CONCLUSION

Intravitreal injection of triamcinolone, bevacizumab or combination of triamcinolone-bevacizumab appears to have similar therapeutic effects on macular edema due to branch retinal vein occlusion at one month. Intravitreal injection of bevacizumab yielded better results of visual acuity than the others at six months.

Visual outcomes in five different approaches for treatment of central retinal vein occlusion

BACKGROUND AND OBJECTIVE

Four treatment methods for central retinal vein occlusion were compared with its natural course.

PATIENTS AND METHODS

In this partially prospective, comparative, interventional case series on 63 eyes with central retinal vein occlusion, five approaches were compared: intravitreal triamcinolone injection; radial optic neurotomy; combined radial optic neurotomy and intraocular triamcinolone injection; combined internal limiting membrane peeling, radial optic neurotomy, and intraocular triamcinolone; and observation.

RESULTS

Final visual acuity in the intravitreal triamcinolone group was better compared with the observation (P = .025), radial optic neurotomy (P = .037), combined radial optic neurotomy/intraocular triamcinolone injection (P = .401), and combined internal limiting membrane peeling, radial optic neurotomy, and intraocular triamcinolone injection (P = .023) groups. However, after adjustment for baseline visual acuity, the only treatment method with significant visual acuity improvement in relation to the observation group was the combined radial optic neurotomy/intraocular triamcinolone injection (P = .025, .023, and .054 at 1, 3, and 6 months, respectively).

CONCLUSION

Among the five different approaches analyzed in this study, combined radial optic neurotomy and intraocular triamcinolone injection may provide a better visual outcome in the management of central retinal vein occlusion.

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.

Intravitreal triamcinolone acetonide vs bevacizumab for treatment of macular oedema secondary to branch retinal vein occlusion

PURPOSE

To compare the short-term visual and morphological results of intravitreal triamcinolone acetonide vsintravitreal bevacizumab for eyes with macular oedema secondary to branch retinal vein occlusion (BRVO).

DESIGN

Retrospective interventional consecutive case series.

METHODS

We reviewed the clinical records of 29 patients (29 eyes) who had macular oedema due to BRVO with minimum follow-up of 6 months. A total of 16 patients were treated with intravitreal injection of 4 mg/0.1ml triamcinolone acetonide. The other 13 patients received intravitreal bevacizumab of 1.25 mg in 0.05 ml. Baseline visual acuity, macular thickness, and intraocular pressure were recorded. Final visual acuity, final macular thickness, intraocular pressure, and adverse events were also recorded throughout the follow-up.

RESULTS

All patients completed at least 6 months of follow-up. There were significant improvement in visual acuity and showed significant macular oedema decrease in optical coherence tomography examination in both the two groups postoperatively. However the therapeutic effects showed no statistically significant difference between these two groups with regard to visual results (F=6.012, P=0.083) and macular thickness decline (F=0.007, P=0.570). Seven eyes developed recurrent macular oedema and received reinjections of triamcinolone acetonide or bevacizumab.

CONCLUSION

These short-term results indicate that intravitreal injection of triamcinolone acetonide or bevacizumab can both improve visual acuity and decrease macular oedema temporarily in eyes with BRVO. However, the therapeutic effects of intravitreal triamcinolone acetonide showed no significant differences compared with intravitreal bevacizumab with regard to anatomical and functional outcomes but seemed to cause more adverse events than bevacizumab.

A randomized trial comparing the efficacy and safety of intravitreal triamcinolone with standard care to treat vision loss associated with macular Edema secondary to branch retinal vein occlusion: the Standard Care vs Corticosteroid for Retinal Vein Occlusion (SCORE) study report 6

OBJECTIVE

To compare the efficacy and safety of 1-mg and 4-mg doses of preservative-free intravitreal triamcinolone with standard care (grid photocoagulation in eyes without dense macular hemorrhage and deferral of photocoagulation until hemorrhage clears in eyes with dense macular hemorrhage) for eyes with vision loss associated with macular edema secondary to branch retinal vein occlusion (BRVO).

METHODS

Multicenter, randomized clinical trial of 411 participants. Main Outcome Measure Gain in visual acuity letter score of 15 or more from baseline to month 12.

RESULTS

Twenty-nine percent, 26%, and 27% of participants achieved the primary outcome in the standard care, 1-mg, and 4-mg groups, respectively. None of the pairwise comparisons between the 3 groups was statistically significant at month 12. The rates of elevated intraocular pressure and cataract were similar for the standard care and 1-mg groups, but higher in the 4-mg group.

CONCLUSIONS

There was no difference identified in visual acuity at 12 months for the standard care group compared with the triamcinolone groups; however, rates of adverse events (particularly elevated intraocular pressure and cataract) were highest in the 4-mg group. Application to Clinical Practice Grid photocoagulation as applied in the SCORE Study remains the standard care for patients with vision loss associated with macular edema secondary to BRVO who have characteristics similar to participants in the SCORE-BRVO trial. Grid photocoagulation should remain the benchmark against which other treatments are compared in clinical trials for eyes with vision loss associated with macular edema secondary to BRVO. Trial Registration clinicaltrials.gov Identifier: NCT00105027.

Bevacizumab (Avastin) for the treatment of ocular disease

The use of intravitreal bevacizumab (Avastin) has greatly expanded since its introduction into ophthalmic care 3 years ago. A PubMed search on 1 August 2008 revealed 51 ocular disease processes that have been treated with bevacizumab. The majority of publications consist of case reports or retrospective case series and their number is increasing quickly. It is important to collate the experiences gained to date to properly inform our clinical decision making and improve the design of future clinical trials. Current studies cannot easily be combined in a meta-analysis given the lack of standardized data and the wide variety of disorders studied in small numbers. This paper will describe the attempted uses of intravitreal bevacizumab and its efficacy for each ocular disease in addition to discussing safety. Comments regarding appropriate use of this treatment are based on our current level of knowledge. It is clear that the initial encouraging results described in this paper warrant further study of intravitreal bevacizumab in larger, controlled, randomized trials.

SCORE Study report 1: baseline associations between central retinal thickness and visual acuity in patients with retinal vein occlusion

OBJECTIVE

To investigate the relationship between baseline center point retinal thickness measured by optical coherence tomography (OCT) and best-corrected visual acuity in eyes with macular edema associated with retinal vein occlusion and to investigate other factors associated with baseline visual acuity letter score.

DESIGN

The Standard Care versus COrticosteroid for REtinal Vein Occlusion (SCORE) Study includes 2 multicenter, randomized clinical trials: one evaluating participants with central retinal vein occlusion (CRVO) and the other evaluating participants with branch retinal vein occlusion (BRVO).

PARTICIPANTS

After omitting 17 participants with missing or unreliable OCT measurements, analyses proceeded with 665 enrolled SCORE Study participants (665 eyes), including 262 with CRVO and 403 with BRVO.

METHODS

At baseline, center point thickness was measured by OCT (Stratus OCT 3 [n=663] and OCT2 [n=2]; Carl Zeiss Meditech, Dublin, CA), and visual acuity was measured by the electronic Early Treatment Diabetic Retinopathy Study (E-ETDRS) methodology.

MAIN OUTCOME MEASURES

Center point thickness and best-corrected E-ETDRS visual acuity letter score.

RESULTS

The correlation coefficient for the association between baseline OCT-measured center point thickness and best-corrected E-ETDRS visual acuity letter score is -0.27 (95% confidence limit: -0.38 to -0.16) for participants in the CRVO trial and -0.28 (95% confidence limit: -0.37 to -0.19) in the BRVO trial. Regression modeling estimated the following decrease in baseline visual acuity letter score for every 100-microm increase in OCT-measured center point thickness: 1.7 letters (P=0.0007) for CRVO and 1.9 letters (P<0.0001) for BRVO. On the basis of multivariate regression models, baseline factors significantly associated (P<0.05, after adjusting for multiple testing) with baseline visual acuity letter score include age and duration of macular edema for CRVO participants and center point thickness and presence of cystoid spaces for BRVO participants.

CONCLUSIONS

The correlation between OCT-measured center point thickness and visual acuity letter score is modest. OCT-measured center point thickness represents a useful tool for the detection and monitoring of macular edema in retinal vein occlusion, but it cannot reliably substitute for visual acuity measurements.

Fluocinolone acetonide sustained drug delivery device for chronic central retinal vein occlusion: 12-month results

PURPOSE

To determine treatment outcomes of a long-acting intravitreal fluocinolone acetonide sustained drug delivery implant in eyes with central retinal vein occlusion (CRVO) and chronic refractory macular edema.

DESIGN

Prospective, noncomparative, interventional case series.

METHODS

Fourteen eyes of 14 patients with chronically persistent macular edema associated with CRVO underwent intraocular implantation of a three-year fluocinolone acetonide sustained drug delivery system. Best-corrected Early Treatment of Diabetic Retinopathy visual acuity (VA), central foveal thickness determined by optical coherence tomography, and intraocular pressure (IOP) were recorded after the first 12 months after implant insertion.

RESULTS

The median (range) vein occlusion and macular edema duration were 12.5 months (range, seven to 49). No eye experienced intraoperative complications. At baseline, median VA was 20/126, improved to 20/60 by two months, and was 20/80 by 12 months. A significant proportion of eyes had gained lines of VA at 12 months compared with baseline (P = .002). At 12 months, the mean and median central retinal thickness decreased from 622 and 600 microm before surgery, respectively, to 307 and 199 microm after surgery, respectively (P = .008). By month 12, cataract had developed in all five phakic patients, and 13 of 14 eyes required medical or surgical IOP-lowering interventions.

CONCLUSIONS

VA improved and macular edema decreased in a significant proportion of implanted eyes with chronic, CRVO-associated macular edema. Cataract formation and elevated IOP, the main side effects, were managed, respectively, with cataract extraction and medical or surgical IOP control, or both. This system is a promising novel alternative to currently available treatments for this challenging patient population.

Intravitreal triamcinolone acetonide for patients with macular oedema due to central retinal vein occlusion in Taiwan

PURPOSE

To evaluate the safety and outcome of intravitreal triamcinolone acetonide as treatment for macular oedema secondary to central retinal vein occlusion (CRVO) in Taiwanese.

METHODS

The prospective clinical interventional study included 43 patients (43 eyes) with macular oedema due to CRVO. The study group consisted of 22 patients who had accepted an intravitreal injection of 4 mg of triamcinolone acetonide. The control group included 21 patients without intravitreal triamcinolone acetonide. Examination included assessment of best-corrected visual acuity, slit-lamp biomicroscopy, measurement of intraocular pressure, ophthalmoscopy, and optical coherence tomography (OCT).

RESULTS

The mean follow-up was 283.00+/-70.62 days in the study group and 354.05+/-173.18 days in the control group, respectively. In the study group, visual acuity measurements improved significantly (P=0.007) from 1.00+/-0.45 logMAR preoperatively to a best postoperative visual acuity of 0.67+/-0.65 logMAR. Seventeen eyes (77.3%) gained improvement in visual acuity with 12 eyes (54.5%) showing an increase in visual acuity of at least two Snellen lines. All 22 patients showed significant macular oedema resolution in OCT examination (P<0.001) from 594.36+/-177.78 mum preoperatively to a mean retinal thickness of 317.23+/-196.83 mum postoperatively postintravitreal injection. In the control group, baseline best-corrected visual acuity and best-corrected visual acuity during the follow-up did not vary significantly (P=0.457).

CONCLUSION

Intravitreal triamcinolone acetonide can lead to a significant improvement in visual acuity and a resolution of macular oedema in patients with CRVO.

[Treatment of central retinal vein occlusion by isovolemic hemodilution]

PURPOSE

Evaluate the effects of hemodilution in the treatment of central retinal vein occlusion (CRVO).

PATIENTS AND METHODS

We carried out a retrospective, noncomparative study of 25 patients presenting unilateral CRVO, treated with one to three hemodilution sessions. The patients were re-examined in the 1st, 2nd, 3rd, 6th and 12th months following treatment with measurement of visual acuity, fluorescein angiography, and optical coherence tomography.

RESULTS

Our study included 17 men and eight women, averaging 63 years of age (range, 35-87 years), and monitored for an average of 7 months (range, 3-12 months). After the 6th month following treatment, average visual acuity improved compared to initial visual acuity. Initial visual acuity of less than 1/10, with the existence of poorly irrigated areas in the angiography, presented negative prognosis factors. The number of hemodilutions did not produce a significant difference in final visual acuity. No serious complications due to hemodilution were observed.

DISCUSSION

Treatment of CRVO is subject to debate. Some practitioners recommend against treatment, while others advocate intervention and offer laser-induced chorioretinal venous anastomosis. Surgical vitrectomy and radial optical neurotomy, with or without injection of triamcinolone, await evaluation. Hemodilution may offer a therapeutic approach to this pathology, in which the etiopathogenesis is not yet recognized, but in which blood viscosity plays a key role. This treatment is well tolerated.

CONCLUSION

Hemodilutions appear to have beneficial effects in treating CRVO, whatever the number of hemodilutions used. This study should be confirmed by a prospective study using an untreated control group.

Safety and pharmokinetics of triamcinolone hexacetonide in rabbit eyes

PURPOSE

The aim of this study was to evaluate whether intravitreal triamcinolone hexacetonide (TH) is a safe, longer lasting alternative to intravitreal triamcinolone acetonide (TA) in the rabbit eye.

METHODS

Three groups, each comprising of 15 Dutch-belted rabbits, received a unilateral injection of 0.1 mL of drug and 0.1 mL of physiologic salt solution in the fellow eye. Group I received TA, group II received commercially available TH, and group III received reformulated iso-osmolar triamcinolone hexacetonide (rTH). Simultaneous bilateral dark-adapted electroretinography was performed following the injection. Retinal morphology was assessed by using histopathology in each group enucleated 12 weeks after injection. High-performance liquid chromatography of vitreous isolated from the enucleated eyes was used to determine drug concentrations.

RESULTS

A significant reduction in saturated a-wave and maximal scotopic b-wave was observed in the group II eyes relative to the fellow control eyes at both 2 and 12 weeks postinjection (P < 0.001 for each comparison) but not in the other groups. Histopathology showed no differences between drug-injected eyes and fellow control eyes in groups I and III, but in group II there was severe degeneration of all retina layers. In group I, the drug half-life was 17.7 +/- 1.7 days, group II 44 +/- 13 days, and group III 12.8 +/- 2.3 days.

CONCLUSIONS

The half-life of commercially available TH in the vitreous is double that of TA, but the former is toxic to the retina in this rabbit model. Reformulated iso-osmolar TH showed no evidence of deleterious effects to retina function or structure but had a similar half-life to TA.

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.

Steroidal and Nonsteroidal Antiinflammatory Medications Can Improve Photoreceptor Survival after Laser Retinal Photocoagulation

OBJECTIVE

To determine whether methylprednisolone or indomethacin can enhance photoreceptor survival after laser retinal injury in an animal model.

DESIGN

Experimental study.

PARTICIPANTS

Twenty rhesus monkeys.

METHODS

Twenty rhesus monkeys (Macaca mulatta) received a grid of argon green (514.5 nm, 10 ms) laser lesions in the macula of the right eye and a grid of neodymium:yttrium-aluminum-garnet (Nd:YAG; 1064 nm, 10 ns) lesions in the macula of the left eye, followed by randomization to 2 weeks of treatment in 1 of 4 treatment groups: high-dose methylprednisolone, moderate-dose methylprednisolone, indomethacin, or control. The lesions were assessed at day 1, day 14, 2 months, and 4 months. The authors were masked to the treatment group. This report discusses the histologic results of ocular tissue harvested at 4 months.

MAIN OUTCOME MEASURE

The number of surviving photoreceptor cell nuclei within each lesion was compared with the number of photoreceptor nuclei in surrounding unaffected retina. The proportion of surviving photoreceptor nuclei was compared between each treatment group.

RESULTS

Argon retinal lesions in the high-dose steroid treatment group and the indomethacin treatment group demonstrated improved photoreceptor survival compared with the control group (P = 0.004). Hemorrhagic Nd:YAG lesions demonstrated improved survivability with indomethacin treatment compared with controls (P = 0.003). In nonhemorrhagic Nd:YAG laser retinal lesions, the lesions treated with moderate-dose steroids demonstrated improved photoreceptor survival compared with the control group (P = 0.004).

CONCLUSIONS

Based on histologic samples of retinal laser lesions 4 months after injury, treatment with indomethacin resulted in improved photoreceptor survival in argon laser lesions and hemorrhagic Nd:YAG laser lesions. Treatment with systemic methylprednisolone demonstrated improved photoreceptor survival in argon retinal lesions and in nonhemorrhagic Nd:YAG lesions.

Novel approaches to retinal drug delivery

Research into treatment modalities affecting vision is rapidly progressing due to the high incidence of diseases such as diabetic macular edema, proliferative vitreoretinopathy, wet and dry age-related macular degeneration and cytomegalovirus retinitis. The unique anatomy and physiology of eye offers many challenges to developing effective retinal drug delivery systems. Historically, drugs have been administered to the eye as liquid drops instilled in the cul-de-sac. However retinal drug delivery is a challenging area. The transport of molecules between the vitreous/retina and systemic circulation is restricted by the blood-retinal barrier, which is made up of retinal pigment epithelium and endothelial cells of the retinal blood vessels. An increase in the understanding of drug absorption mechanisms into the retina from local and systemic administration has led to the development of various drug delivery systems, such as biodegradable and non-biodegradable implants, microspheres, nanoparticles and liposomes, gels and transporter-targeted prodrugs. Such diversity in approaches is an indication that there is still a need for an optimized noninvasive or minimally invasive drug delivery system to the eye. A number of large molecular weight compounds (i.e., oligonucleotides, RNA aptamers, peptides and monoclonal antibodies) have been and continue to be introduced as new therapeutic entities. However, for high molecular weight polar compounds the mechanism of epithelial transport is primarily through the tight junctions in the retinal pigment epithelium, as these agents undergo limited transcellular diffusion. Delivery and administration of these new drugs in a safe and effective manner is still a major challenge facing pharmaceutical scientists. In this review article, the authors discuss various drug delivery strategies, devices and challenges associated with drug delivery to the retina.

Intravitreal triamcinolone acetonide for the management of papillophlebitis and associated macular edema

BACKGROUND

To investigate the efficacy of intravitreal injection of triamcinolone acetonide in the management of papillophlebitis and associated cystoid macular edema.

METHODS

This study was a retrospective medical records review of four eyes of four patients (three males and one female) who had approximately 2-4 months history of papillophlebitis and associated persistent cystoid macular edema. These patients were treated with a single intravitreal injection of 4 mg triamcinolone acetonide. Mean follow-up time was 15 +/- 4 months. The outcome measures included best corrected visual acuity (BCVA), intraocular pressure (IOP), and central retinal thickness by optical coherence tomography (OCT).

RESULTS

The BCVA ranged from 20/100 to 20/60 pre-operation. The mean gain in BCVA was 7 +/- 1 Snellen lines. All eyes had BCVA of 20/20 at the last visit. The mean baseline central retinal thickness as measured by OCT was 529 +/- 53 microm. The mean central retinal thickness by OCT was 235 +/- 15 microm at 1-week follow-up examination. At the last visit the mean central retinal thickness by OCT was 161 +/- 7 microm. One patient experienced an increase in IOP after the first injection and another patient had IOP elevation after the second injection. Both were well controlled with single topical anti-glaucoma medication.

CONCLUSION

Intravitreal injection of triamcinolone acetonide appears to be an effective treatment for patients with papillophlebitis and associated cystoid macular edema.

Macular hole and intravitreal injection of triamcinolone acetonide for macular edema due to central retinal vein occlusion

PURPOSE

To report a case of macular hole progression after intravitreal injection of triamcinolone acetonide (IVTA) for chronic macular edema secondary to nonischemic central retinal vein occlusion (CRVO).

METHODS

A 33-year-old woman with massive macular edema after CRVO underwent IVTA. Optical coherence tomography (OCT) and fluorescein angiography were performed before and after the procedure.

RESULTS

At the 1-week IVTA injection control, the patient's best-corrected visual acuity improved from 20/400 to 20/200 and OCT detected a progression of macular hole stage.

CONCLUSIONS

IVTA steroid injection may provide a significant improvement in macular edema, but injection-related complications may occur such as this uncommon macular reaction resulting in permanent visual loss.

Hemodynamic response to intravitreal triamcinolone in eyes with macular edema

PURPOSE

To assess ocular hemodynamic response to intravitreal triamcinolone in patients with macular edema due to diabetes or retinal vein occlusion.

METHODS

Forty-three patients that were injected by intravitreal triamcinolone acetonide (0.1 cc 4 mg) for unilateral macular edema due to diabetes mellitus (n = 17) and occlusion of retinal vein (n = 26) underwent ocular hemodynamic evaluation by color Doppler imaging (CDI) before and one, two and three months after injection. Non-injected fellow eyes as well as 16 healthy volunteers were also evaluated.

RESULTS

In patients with diabetic macular edema, there was no hemodynamic difference between eyes to be injected and non-injected at baseline (P > 0.23). Compared to controls, a significant difference existed in the ophthalmic artery resistant index (P = 0.001) and end-diastolic velocity (P < 0.001) in diabetics. At one month, compared to fellow eyes, change in end diastolic velocity from baseline in treated eyes was significantly decreased in posterior ciliary arteries (0.68 +/- 0.34 cm/s [mean +/- SEM] vs. -1.04 +/- 0.81 cm/s, P = 0.012). Throughout the study period, no significant alteration from baseline in the resistant index of any artery was noted in treated diabetic eyes (P > 0.05). In eyes with retinal vein occlusion, baseline CDI evaluation demonstrated reduced posterior ciliary arteries systolic flow velocity compared to fellow and control eyes (13.24 +/- 1.04 cm/s, 16.37 +/- 0.76 cm/s and 14.33 +/- 1.41 cm/s, respectively, P = 0.007). Increased peak systolic velocity in the posterior ciliary arteries at one week (P = 0.02), one month (P = 0.005) and two months (P = 0.04), and increase in central retinal artery resistant index at one month was noted (P = 0.05).

CONCLUSION

Intravitreal triamcinolone temporarily changed central retinal artery blood flow and posterior ciliary arteries' peak systolic blood velocity in eyes with retinal vein occlusion whilst no response of blood flow to triamcinolone injection but only transiently altered end diastolic blood velocity in posterior ciliary arteries was observed in diabetic eyes.

Intravitreal bevacizumab (avastin) for central and hemicentral retinal vein occlusions: IBeVO study

PURPOSE

To evaluate the safety, visual acuity changes, and morphologic effects associated with intravitreal bevacizumab injections for the management of macular edema due to ischemic central or hemicentral retinal vein occlusion (RVO).

METHODS

In this prospective, open-label study, 7 consecutive patients (7 eyes) with macular edema associated with ischemic central or hemicentral RVO were treated with intravitreal injections of 2.0 mg (0.08 mL) of bevacizumab at 12-week intervals. Standardized ophthalmic evaluation was performed at baseline and at weeks 1, 6, and 12 after each injection. Clinical evidence of toxicity and complications as well as changes in logarithm of minimum angle of resolution Early Treatment Diabetic Retinopathy Study best-corrected visual acuity (BCVA), central macular thickness (CMT) and total macular volume (TMV) shown by optical coherence tomography (OCT), and dye leakage shown by fluorescein angiography were evaluated.

RESULTS

The median age of the 7 patients was 65 years (range, 58-74 years), and the median duration of symptoms before injection was 7 months (range, 2.5-16 months). At baseline, mean BCVA was 1.21 (Snellen equivalent, approximately 20/320) in the affected eye. Mean baseline CMT and TMV were 730.1 microm and 17.1 mm(3), respectively. Fluorescein leakage was observed in the macula and affected retinal quadrants in all seven eyes. Six patients completed the 25-week follow-up examination with reinjections performed at weeks 12 and 24. The most common adverse events were conjunctival hyperemia and subconjunctival hemorrhage at the injection site. At the last follow-up, mean BCVA in the affected eye was 0.68 (Snellen equivalent, 20/100(+1). No patient had a decrease in BCVA. Mean CMT and TMV at the 25-week follow-up were 260.3 microm and 9.0 mm(3), respectively; fluorescein leakage within the macula and affected retinal quadrants as compared with baseline was markedly reduced in all patients. Coupled with fluorescein angiographic findings, OCT data suggest a trend of macular edema recurrence between 6 weeks and 12 weeks after injection.

CONCLUSIONS

Intravitreal bevacizumab injections of 2.0 mg at 12-week intervals were well tolerated and were associated with short-term BCVA stabilization or improvement and favorable macular changes in all patients with ischemic RVO and associated macular edema.

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 steroids in the management of macular oedema

The use of intravitreal corticosteroids in the management of macular oedema has recently gained widespread acceptance. New long-acting steroid preparations and methods of delivery have facilitated the use of these new modalities. This review describes the various types of macular oedema for which this therapeutic option is used and the results.

Retinal toxicity of intravitreal triamcinolone acetonide at high doses in the rabbit

In order to study acute retinal toxicity of intravitreal triamcinolone acetonide (TA) at high doses in an animal model, thirty New Zealand albino rabbits were injected with intravitreal TA. The animals were divided in five groups: Group 1 received an intravitreal injection of 0.1 mL balanced salt solution; Group 2, 0.1 mL of the solvent (0.99 mg of benzyl alcohol); Group 3, received 4 mg/0.1 mL TA; Group 4, 20mg/0.1 mL TA; and Group 5, 30 mg/0.1 mL TA. A standard light and dark adapted electroretinogram (ERG) was obtained prior and 28 days after the injection. The animals were sacrificed 28 days after the injection and the eyes were enucleated and examined by electron (EM) and light microscopy (LM) using hematoxylin-eosin, Nissl fluorescent, and immunohistochemistry (glial fibrillary acidic protein). No statistically significant differences in ERG before and 28 days after the injection were found. LM and EM did not show retinal damage in any animal. One eye developed bacterial endophthalmitis 14 days after the injection. Intravitreal TA up to 30 mg does not seem to have acute toxic effects on the function (ERG) or the structure (LM, EM) of the retina of albino rabbits.