INTRAVITREAL TRIAMCINOLONE ACETONIDE FOR DIABETIC MACULAR EDEMA

Non-vasogenic cystoid maculopathies

Besides cystoid macular edema due to a blood-retinal barrier breakdown, another type of macular cystoid spaces referred to as non-vasogenic cystoid maculopathies (NVCM) may be detected on optical coherence tomography but not on fluorescein angiography. Various causes may disrupt retinal cell cohesion or impair retinal pigment epithelium (RPE) and Müller cell functions in the maintenance of retinal dehydration, resulting in cystoid spaces formation. Tractional causes include vitreomacular traction, epiretinal membranes and myopic foveoschisis. Surgical treatment does not always allow cystoid space resorption. In inherited retinal dystrophies, cystoid spaces may be part of the disease as in X-linked retinoschisis or enhanced S-cone syndrome, or occur occasionally as in bestrophinopathies, retinitis pigmentosa and allied diseases, congenital microphthalmia, choroideremia, gyrate atrophy and Bietti crystalline dystrophy. In macular telangiectasia type 2, cystoid spaces and cavitations do not depend on the fluid leakage from telangiectasia. Various causes affecting RPE function may result in NVCM such as chronic central serous chorioretinopathy and paraneoplastic syndromes. Non-exudative age macular degeneration may also be complicated by intraretinal cystoid spaces in the absence of fluorescein leakage. In these diseases, cystoid spaces occur in a context of retinal cell loss. Various causes of optic atrophy, including open-angle glaucoma, result in microcystoid spaces in the inner nuclear layer due to a retrograde transsynaptic degeneration. Lastly, drug toxicity may also induce cystoid maculopathy. Identifying NVCM on multimodal imaging, including fluorescein angiography if needed, allows guiding the diagnosis of the causative disease and choosing adequate treatment when available.

The Role of Intravitreal Corticosteroids in the Treatment of DME: Predictive OCT Biomarkers

This work aims to summarize predictive biomarkers to guide treatment choice in DME. Intravitreal anti-VEGF is considered the gold standard treatment for centers involving DME, while intravitreal steroid treatment has been established as a second-line treatment in DME. However, more than 1/3 of the patients do not adequately respond to anti-VEGF treatment despite up to 4-weekly injections. Not surprisingly, insufficient response to anti-VEGF therapy has been linked to low-normal VEGF levels in the serum and aqueous humor. These patients may well benefit from an early switch to intravitreal steroid treatment. In these patients, morphological biomarkers visible in OCT may predict treatment response and guide treatment decisions. Namely, the presence of a large amount of retinal and choroidal hyperreflective foci, disruption of the outer retinal layers and other signs of chronicity such as intraretinal cysts extending into the outer retina and a lower choroidal vascular index are all signs suggestive of a favorable treatment response of steroids compared to anti-VEGF. This paper summarizes predictive biomarkers in DME in order to assist individual treatment decisions in DME. These markers will help to identify DME patients who may benefit from primary dexamethasone treatment or an early switch.

Current and Novel Therapeutic Approaches for Treatment of Diabetic Macular Edema

Diabetic macular edema (DME) is a major ocular complication of diabetes mellitus (DM), leading to significant visual impairment. DME’s pathogenesis is multifactorial. Focal edema tends to occur when primary metabolic abnormalities lead to a persistent hyperglycemic state, causing the development of microaneurysms, often with extravascular lipoprotein in a circinate pattern around the focal leakage. On the other hand, diffusion edema is due to a generalized breakdown of the inner blood–retinal barrier, leading to profuse early leakage from the entire capillary bed of the posterior pole with the subsequent extravasation of fluid into the extracellular space. The pathogenesis of DME occurs through the interaction of multiple molecular mediators, including the overexpression of several growth factors, including vascular endothelial growth factor (VEGF), insulin-like growth factor-1, angiopoietin-1, and -2, stromal-derived factor-1, fibroblast growth factor-2, and tumor necrosis factor. Synergistically, these growth factors mediate angiogenesis, protease production, endothelial cell proliferation, and migration. Treatment for DME generally involves primary management of DM, laser photocoagulation, and pharmacotherapeutics targeting mediators, namely, the anti-VEGF pathway. The emergence of anti-VEGF therapies has resulted in significant clinical improvements compared to laser therapy alone. However, multiple factors influencing the visual outcome after anti-VEGF treatment and the presence of anti-VEGF non-responders have necessitated the development of new pharmacotherapies. In this review, we explore the pathophysiology of DME and current management strategies. In addition, we provide a comprehensive analysis of emerging therapeutic approaches to the treatment of DME.

Secondary glaucoma after intravitreal dexamethasone implant (Ozurdex) injection in patients with retinal disorder: A retrospective study

Purpose:

To investigate the rate of secondary glaucoma after intravitreal (IV) dexamethasone implant (ozurdex) 0.7 mg injection in a retinal disorder over a clinical treatment period of 2 years in a tertiary eye care center.

Methods:

Retrospective study based on the records of patients receiving IV ozurdex 0.7 mg implant for T/t of cystoid macular edema (CME), diabetic macular edema (DME), macular edema due to central retinal vein occlusion/branch retinal vein occlusion (CRVO/BRVO), and choroidal neovascular membrane (CNVM) at a tertiary eye care hospital for 2 years with 6 months of follow-up. The post-T/t intraocular pressure (IOP) and antiglaucoma medication (AGM) required was recorded at day 1, 1 week, 1, 2, 3, 4, and 6 months and analyzed for secondary IOP spike or ocular hypertension defined as IOP >21 mmHg at any point in time. The patients with pre-existing glaucoma and lost to follow-up were excluded.

Results:

A total of 102 eyes of 80 patients were included in the study. The mean baseline IOP was 14.40 + 2.97 mmHg, post-injection was 15.01 + 3.22 mmHg at day 1, 15.15 + 3.28 mmHg at 1 week, 15.96 + 3.62 mmHg at 1 month, 16.26 + 3.95 mmHg at 2 months, 15.41 + 3.33 mmHg at 3 months, 15.38 + 3.28 mmHg at 4 months, and 14.27 + 2.69 mmHg at 6 months. No significant difference was seen from baseline IOP at day 1 (P = 0.163), 1 week (P = 0.086), and 6 months (P = 0.748). Statistically significant difference was seen at 1 month (P = 0.0009), 2 months (P = 0.0001), 3 months (P = 0.023), and 4 months (P = 0.026). The mean IOP peak at 2 months recovered to baseline by 6 months subgroup IOP trend shows a similar variation and the results are consistent with the studies in the literature. About 19/102 (18.62%) eyes showed an IOP spike post-T/t. The maximum was seen at 2 months; 16 eyes showed a rise in the range 22–25 mmHg; 8 in the range 26–30 mmHg; and 1 eye had 34 mmHg and required multiple AGM—no surgical intervention was needed.

Conclusion:

A secondary IOP spike post-IV ozurdex 0.7 mg seen in 18.62% of the cases require AGM. The IOP monitoring should be meticulously performed for the variations and secondary IOP spike management to prevent irreversible damage to the optic nerve and visual field.

Noninfectious endophthalmitis following intravitreal triamcinolone acetonide: clinical case and literature review

OBJECTIVE

To review the literature on noninfectious endophthalmitis (NIE) following intravitreal triamcinolone acetonide (IVTA).

DESIGN

A literature review and case report.

PARTICIPANTS

Individuals who developed NIE after IVTA injection.

METHODS

A review of the literature was undertaken using Ovid MEDLINE and EMBASE databases, and articles available up to and including December 30, 2019, were included. A total of 518 articles were identified, of which 27 were selected. We also present an illustrative case report.

RESULTS

The incidence rate of NIE lies between 0.1% and 7.3% in most studies. Although the etiology of NIE is still the subject of investigation, proposed mechanisms include excipients and rheologic stress caused by small crystals. The time to presentation of NIE is often 1-3 days after IVTA injection, with symptoms of moderate to marked reduction in visual acuity along with signs of anterior chamber inflammatory reaction, hypopyon, and vitritis. Resolution occurs in 1-3 weeks in the majority of patients, and almost all return to their pre-injection visual acuity. Differences in the presentations of NIE, infectious endophthalmitis, and pseudo-endophthalmitis are discussed. We also present an illustrative case report of an 80-year-old woman who developed NIE after an IVTA injection for cystoid macular edema.

CONCLUSIONS

It is important to distinguish NIE from other forms of endophthalmitis because they have different natural histories and require different interventions and follow-up. NIE is rarely accompanied by significant pain or conjunctival erythema. Visual acuity is inconsistently affected and is therefore not a good criterion for identifying the type of presenting endophthalmitis.

A Quantitative Approach to Predict Differential Effects of Anti-VEGF Treatment on Diffuse and Focal Leakage in Patients with Diabetic Macular Edema: A Pilot Study

Purpose

We use semiautomated segmentation of fluorescein angiography (FA) to determine whether anti-vascular endothelial growth factor (VEGF) treatment for diabetic macular edema (DME) differentially affects microaneurysm (MA)–associated leakage, termed focal leakage, versus non-MA–associated leakage, termed diffuse leakage.

Methods

We performed a retrospective study of 29 subjects treated with at least three consecutive injections of anti-VEGF agents for DME (mean 4.6 injections; range, 3–10) who underwent Heidelberg FA before and after anti-VEGF therapy. Inclusion criteria were macula center involving DME and at least 3 consecutive anti-VEGF injections. Exclusion criteria were macular edema due to cause besides DME, anti-VEGF within 3 months of initial FA, concurrent treatment for DME besides anti-VEGF, and macular photocoagulation within 1 year. At each time point, total leakage was semiautomatically segmented using a modified version of our previously published software. Microaneurysms were identified by an expert grader and leakage within a 117 μm radius of each MA was classified as focal leakage. Remaining leakage was classified as diffuse leakage. The absolute and percent changes in total, diffuse, and focal leakage were calculated for each subject.

Results

Mean pretreatment total leakage was 8.2 mm² and decreased by a mean of 40.1% (P < 0.0001; 95% confidence interval [CI], [−28.6, −52.5]) following treatment. Diffuse leakage decreased by a mean of 45.5% (P < 0.0001; 95% CI, [−31.3, −59.6]) while focal leakage decreased by 17.9% (P = 0.02; 95% CI, [−1.0, −34.8]). The difference in treatment response between focal and diffuse leakage was statistically significant (P = 0.01).

Conclusions

Anti-VEGF treatment for DME results in decreased diffuse leakage but had relatively little effect on focal leakage as assessed by FA. This suggests that diffuse leakage may be a marker of VEGF-mediated pathobiology. Patients with predominantly focal leakage may be less responsive to anti-VEGF therapy.

Translational Relevance

Fluorescein angiography can define focal and diffuse subtypes of diabetic macular edema and these may respond differently to anti-VEGF treatment.

Role of implants in the treatment of diabetic macular edema: focus on the dexamethasone intravitreal implant

Diabetic macular edema (DME) is the leading cause of sight-threatening complication in diabetic patients, and several treatment modalities have been developed and evaluated to treat this pathology. Intravitreal agents, such as anti-vascular endothelial growth factors (anti-VEGF) or corticosteroids, have become more popular in recent years and are widely used for treating DME. Sustained release drugs appear to be mentioned more often nowadays for extending the period of intravitreal activity, and corticosteroids play a key role in inhibiting the inflammatory process in DME. A potent corticosteroid, dexamethasone (Ozurdex(®)), in the form of an intravitreal implant, has been approved for various ocular etiologies among which DME is also one. This review evaluates the role of implants in the treatment of DME, mainly focusing on the dexamethasone intravitreal implant.

Modulation of VEGF-induced retinal vascular permeability by peroxisome proliferator-activated receptor-β/δ

PURPOSE

Vascular endothelial growth factor (VEGF)-induced retinal vascular permeability contributes to diabetic macular edema (DME), a serious vision-threatening condition. Peroxisome proliferator-activated receptor β/δ (PPARβ/δ) antagonist/reverse agonist, GSK0660, inhibits VEGF-induced human retinal microvascular endothelial cell (HRMEC) proliferation, tubulogenesis, and oxygen-induced retinal vasculopathy in newborn rats. These VEGF-induced HRMEC behaviors and VEGF-induced disruption of endothelial cell junctional complexes may well share molecular signaling events. Thus, we sought to examine the role of PPARβ/δ in VEGF-induced retinal hyperpermeability.

METHODS

Transendothelial electrical resistance (TEER) measurements were performed on HRMEC monolayers to assess permeability. Claudin-1/Claudin-5 localization in HRMEC monolayers was determined by immunocytochemistry. Extracellular signal-regulated protein kinases 1 and 2 (Erk 1/2) phosphorylation, VEGF receptor 1 (VEGFR1) and R2 were assayed by Western blot analysis. Expression of VEGFR1 and R2 was measured by quantitative RT-PCR. Last, retinal vascular permeability was assayed in vivo by Evans blue extravasation.

RESULTS

Human retinal microvascular endothelial cell monolayers treated with VEGF for 24 hours showed decreased TEER values that were completely reversed by the highest concentration of GSK0660 (10 μM) and PPARβ/δ-directed siRNA (20 μM). In HRMEC treated with VEGF, GSK0660 stabilized tight-junctions as evidenced by Claudin-1 staining, reduced phosphorylation of Erk1/2, and reduced VEGFR1/2 expression. Peroxisome proliferator-activated receptor β/δ siRNA had a similar effect on VEGFR expression and Claudin-1, supporting the specificity of GSK0660 in our experiments. Last, GSK0660 significantly inhibited VEGF-induced retinal vascular permeability and reduced retinal VEGFR1and R2 levels in C57BL/6 mice.

CONCLUSIONS

These data suggest a protective effect for PPARβ/δ antagonism against VEGF-induced vascular permeability, possibly through reduced VEGFR expression. Therefore, antagonism/reverse agonism of PPARβ/δ siRNA may represent a novel therapeutic methodology against retinal hyperpermeability and is worthy of future investigation.

Intravitreal bevacizumab versus posterior subtenon triamcinolone in diffuse diabetic macular edema

The aim of the study was to compare intravitreal bevacizumab (IVB) and posterior subtenon triamcinolone (PST) as an adjunct to laser treatment in diffuse diabetic macular edema (Diffuse DME). Prospective-randomized control trial of 30 eyes of 30 diabetic patients having Diffuse DME with maximum retinal thickness (MRT) was more than or equal to 350 µm. The subjects were randomly allocated into two groups. Group A (12 eyes) received IVB and group B received PST (18 patients) before laser treatment. Grid laser treatment was done when the MRT decreased to less than 350 µm. OCT thickness-guided repeat injections were given if required. The patients had minimum follow-up of 6 months. At 6-month follow-up, the two groups were compared for (1) Maximum change in visual acuity letter score using logMAR chart (2) Reduction in MRT on OCT. The mean logMAR visual acuity at baseline was 0.63 ± 0.45 (0-1.6) in group A and was 0.76 ± 0.38 (0.2-1.3) in group B. The mean logMAR visual acuity at 6 month in group A was 0.34 ± 0.21 (0-0.6) and in group B was 0.64 ± 0.37 (0.3-1.3). The mean visual acuity at last follow-up was significantly better in group A than group B (p = 0.02). The mean change in MRT in Group A and Group B was 177.8 ± 85.64 and 156.07 ± 102.86, respectively, which was significantly better than the baseline in both the groups and was comparable in both groups. The study provides evidence to support the use of IVB over PST in diffuse diabetic macular edema.

Peroxisome proliferator-activated receptor-β/δ regulates angiogenic cell behaviors and oxygen-induced retinopathy

PURPOSE

To develop new therapies against ocular neovascularization (NV), we tested the effect of peroxisome proliferator-activated receptor-β/δ (PPAR-β/δ) agonism and antagonism on angiogenic behaviors and in human retinal microvascular endothelial cells (HRMEC) and on preretinal NV in rat oxygen-induced retinopathy (OIR).

METHODS

HRMECs were treated with the PPAR-β/δ agonist GW0742 and the antagonist GSK0660. Messenger RNA levels of a PPAR-β/δ target gene, angiopoietin-like-4 (angptl4) were assayed by qRT-PCR. HRMEC proliferation and tube formation were assayed according to standard protocols. OIR was induced in newborn rats by exposing them to alternating 24-hour episodes of 50% and 10% oxygen for 14 days. OIR rats were treated with GW0742 or GSK0660. Angptl4 protein levels were assessed by ELISA and preretinal NV was quantified by adenosine diphosphatase staining.

RESULTS

GW0742 significantly increased angptl4 mRNA, and GSK0660 significantly decreased angptl4 mRNA. GW0742 had no effect on HRMEC proliferation, but caused a significant and dose-responsive increase in tube formation. GSK0660 significantly reduced serum-induced HRMEC proliferation and tube formation in a dose-dependent manner. Intravitreal injection of GW0742 significantly increased total retinal Angptl4 protein, but intravitreal injection of GSK0660 had no effect. Intravitreal injection of GW0742 significantly increased retinal NV, as did GW0742 administered by oral gavage. Conversely, both intravitreal injection and intraperitoneal injection of GSK0660 significantly reduced retinal NV.

CONCLUSIONS

PPAR-β/δ activation exacerbates, and its inhibition reduces, preretinal NV. PPAR-β/δ may regulate preretinal NV through a prodifferentiation/maturation mechanism that depends on Angptl4. Pharmacologic inhibition of PPAR-β/δ may provide a rational basis for therapeutic targeting of ocular NV.

Intravitreal bevacizumab plus grid laser photocoagulation or intravitreal bevacizumab or grid laser photocoagulation for diffuse diabetic macular edema: results of the Pan-american Collaborative Retina Study Group at 24 months

PURPOSE

To evaluate the anatomical and functional outcomes at 24 months in patients with diffuse diabetic macular edema treated with primary intravitreal bevacizumab (IVB) plus grid laser photocoagulation (GLP) or primary IVB alone or GLP alone.

METHODS

Retrospective, interventional, comparative, multicenter study. We included in this analysis 141 eyes of 120 patients with diffuse diabetic macular edema treated with primary IVB alone (Group A), 120 eyes of 94 patients with GLP therapy (Group B), and 157 eyes of 104 patients treated with IVB plus GLP (Group C).

RESULTS

In all 3 groups, the authors observed improvement of Early Treatment Diabetic Retinopathy Study best-corrected visual acuity from baseline to 24-month follow-up (P < 0.0001). The improvement rate in Group A was statistically significantly better than in Group B (analysis of variance, P = 0.013). The authors also found a decrease in central macular thickness in all groups from baseline to the 24-month follow-up (P < 0.0001). The comparison among 3 groups showed higher central macular thickness decrease in Group A than in Groups B and C (analysis of variance, P < 0.001).

CONCLUSION

The study provides evidence to support the use of primary IVB with or without GLP as treatment of diffuse diabetic macular edema. Primary IVB without GLP seems to be superior to GLP alone to provide stability or improvement in best-corrected visual acuity in patients with diffuse diabetic macular edema at 24 months.

[Triamcinolone acetonide without solvents]

OBJECTIVE

The purification of commercially prepared triamcinolone acetonide is important in order to avoid the potential toxic side-effects of the solvent benzyl alcohol. We present a new technique for preparation of pure triamcinolone acetonide by dissolving the powder in sterile distilled water with no additional solvents. As the triamcinolone powder is relatively insoluble in water, we describe the sterile method used for the preparation and control of this suspension.

MATERIALS AND METHODS

The triamcinolone acetonide is prepared in our hospital pharmacy, under optimum sterile conditions, and then packaged in a primary vial, sealed and sterilized in an autoclave at 121°C. This vial contains an individual dose of 4mg/0.1ml.

RESULTS

A final dose for an intravitreal administration of 3.77mg/0.1ml triamcinolone acetonide was obtained using high pressure liquid chromatography (HPLC). The chemical, physical and microbiological stability allows the solution to be kept at a temperature of 2-8°C for 6 months.

CONCLUSIONS

A rapid method is presented for preparing triamcinolone acetonide in pure state without preservatives in a concentration near the standard dose and under optimum sterile conditions.

Off-label use of intravitreal triamcinolone acetonide for diabetic macular edema in a pregnant patient

We present a case of diabetic macular edema in a pregnant patient treated with a single intravitreal injection of triamcinolone acetonomide. Initial presentation and serial examinations after treatment included visual acuity, slit-lamp examination, indirect ophthalmoscopy, and optical coherence tomography. Resolution of visual acuity and macular edema were present six weeks after injection and persisted throughout the duration of the pregnancy without further intervention. No adverse outcomes for either mother or fetus were noted. To our knowledge, this is the first report of intravitreal triamcinolone administration in this patient population to be published in the medical literature.

Association of fluorescein angiographic features with visual acuity and with optical coherence tomographic and stereoscopic color fundus photographic features of diabetic macular edema in a randomized clinical trial

BACKGROUND

Fluorescein angiography (FA) has been performed as part of the management of diabetic macular edema for many years. Its current role relative to the role of optical coherence tomography (OCT) is not well defined.

PURPOSE

To evaluate the associations of FA features with visual acuity (VA) and with OCT and fundus photographic characteristics in eyes with diabetic macular edema.

METHODS

In a clinical trial, conducted by the Diabetic Retinopathy Clinical Research Network to compare two methods of laser photocoagulation to treat diabetic macular edema, FA (film and digital), color photographs, OCT, and VA measurements were obtained at baseline and at 1 year. Grading of morphologic features was performed at a reading center. Reproducibility of FAs was assessed, and the correlations of FA features with VA, OCT, and color photograph features were computed.

RESULTS

From 79 clinical sites, data of 323 study eyes and 203 fellow nonstudy eyes were analyzed. Fluorescein leakage area at baseline was associated with reduced VA, increased OCT measures of retinal thickness and volume, and color photographic measurements of retinal thickening (r = 0.33-0.58). No important associations were found with changes from baseline to 12 months in these parameters or with any of the other variables analyzed.

CONCLUSION

Fluorescein leakage is associated with VA and some OCT and color photographic variables. We did not identify any unique FA variables that had a stronger association with VA than OCT measures of retinal thickness. These data may be useful to investigators planning future diabetic macular edema clinical trials.

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.

A randomized trial comparing the efficacy and safety of intravitreal triamcinolone with observation to treat vision loss associated with macular edema secondary to central retinal vein occlusion: the Standard Care vs Corticosteroid for Retinal Vein Occlusion (SCORE) study report 5

OBJECTIVE

To compare the efficacy and safety of 1-mg and 4-mg doses of preservative-free intravitreal triamcinolone with observation for eyes with vision loss associated with macular edema secondary to perfused central retinal vein occlusion (CRVO).

METHODS

Multicenter, randomized, clinical trial of 271 participants.

MAIN OUTCOME MEASURE

Gain in visual acuity letter score of 15 or more from baseline to month 12.

RESULTS

Seven percent, 27%, and 26% of participants achieved the primary outcome in the observation, 1-mg, and 4-mg groups, respectively. The odds of achieving the primary outcome were 5.0 times greater in the 1-mg group than the observation group (odds ratio [OR], 5.0; 95% confidence interval [CI], 1.8-14.1; P = .001) and 5.0 times greater in 4-mg group than the observation group (OR, 5.0; 95% CI, 1.8-14.4; P = .001); there was no difference identified between the 1-mg and 4-mg groups (OR, 1.0; 95% CI, 0.5-2.1; P = .97). The rates of elevated intraocular pressure and cataract were similar for the observation and 1-mg groups, but higher in the 4-mg group.

CONCLUSIONS

Intravitreal triamcinolone is superior to observation for treating vision loss associated with macular edema secondary to CRVO in patients who have characteristics similar to those in the SCORE-CRVO trial. The 1-mg dose has a safety profile superior to that of the 4-mg dose. Application to Clinical Practice Intravitreal triamcinolone in a 1-mg dose, following the retreatment criteria applied in the SCORE Study, should be considered for up to 1 year, and possibly 2 years, for patients with characteristics similar to those in the SCORE-CRVO trial. Trial Registration clinicaltrials.gov Identifier: NCT00105027.

Primary intravitreal bevacizumab for diffuse diabetic macular edema: the Pan-American Collaborative Retina Study Group at 24 months

PURPOSE

To report the 24-month anatomic and Early Treatment Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (BCVA) response after primary intravitreal bevacizumab (Avastin; Genentech, Inc., San Francisco, CA; 1.25 or 2.5 mg) in patients with diffuse diabetic macular edema (DDME). In addition, a comparison of the 2 different doses of intravitreal bevacizumab (IVB) used is presented.

DESIGN

Retrospective, multicenter, interventional, comparative case series.

PARTICIPANTS

The clinical records of 115 consecutive patients (139 eyes) with DDME at 11 centers from 8 countries were reviewed.

METHODS

Patients were treated with at least 1 intravitreal injection of 1.25 or 2.5 mg of bevacizumab. All patients were followed up for 24 months. Patients underwent ETDRS BCVA testing, ophthalmoscopic examination, optical coherence tomography (OCT), and fluorescein angiography (FA) at the baseline, 1-, 3-, 6-, 12-, and 24-month visits.

MAIN OUTCOME MEASURES

Changes in BCVA and OCT results.

RESULTS

The mean age of the patients was 59.4+/-11.1 years. The mean number of IVB injections per eye was 5.8 (range, 1-15 injections). In the 1.25-mg group at 1 month, BCVA improved from 20/150 (0.88 logarithm of the minimum angle of resolution [logMAR] units) to 20/107, 0.76 logMAR units (P<0.0001). The mean BCVA at 24 months was 20/75 (0.57 logMAR units; P<0.0001). Similar BCVA changes were observed in the 2.5-mg group: at 1 month, BCVA improved from 20/168 (0.92 logMAR units) to 20/118 (0.78 logMAR units; P = 0.02). The mean BCVA at 24 months was 20/114 (0.76 logMAR units; P<0.0001). In the 1.25-mg group, the mean central macular thickness (CMT) decreased from 466.5+/-145.2 microm at baseline to 332.2+/-129.6 microm at 1 month and 286.6+/-81.5 microm at 24 months (P<0.0001). Similar results were obtained in the 2.5-mg group.

CONCLUSIONS

Primary IVB at doses of 1.25 to 2.5 mg seem to provide stability or improvement in BCVA, OCT, and FA in DDME at 24 months. The results show no evident difference between IVB at doses of 1.25 or 2.5 mg.

Intravitreal bevacizumab (Avastin) prevention of panretinal photocoagulation-induced complications in patients with severe proliferative diabetic retinopathy

PURPOSE

To evaluate the efficacy of intravitreal injection of bevacizumab (Avastin) (IVA) in preventing panretinal photocoagulation (PRP)-induced macular thickening and visual dysfunction in eyes with severe proliferative diabetic retinopathy.

METHODS

A retrospective review of 60 consecutive eyes (30 patients) with severe proliferative diabetic retinopathy whose visual acuity was 20/30 or better (<0.18 in logarithm of the minimum angle of resolution acuity) and average foveal thickness (FT) was 280 microm or less, and whose retinopathy was bilateral and symmetrical, was performed. In all eyes, PRP was performed in two sessions. In the interventional group, 1.25 mg of IVA was injected to each eye 1 week before initiation of PRP. Foveal thickness was measured by optical coherence tomography before treatment, and the clinical course was monitored by best corrected visual acuity (BCVA) and FT for 24 weeks after beginning PRP.

RESULTS

Before treatment, mean BCVA and FT was 0.073 +/- 0.071 microm and 278.8 +/- 29.5 microm in the IVA-injected group and 0.069 +/- 0.076 microm and 273.5 +/- 27.7 microm in the control group, respectively. After the IVA injection and PRP completion, FT in the IVA-injected eyes was significantly decreased, with a mean FT of 257.2 microm at 12 weeks and 264.3 microm at 24 weeks. In the control group, FT increased dramatically and reached 307.3 microm at 12 weeks and 298.2 microm at 24 weeks. The difference in final FT between groups was significant (P = 0.001). Best corrected visual acuity in the control group decreased with time to 0.149 +/- 0.113 at 24 weeks; in contrast, BCVA in the IVA-injected eyes improved over time to 0.039 +/- 0.054 at 24 weeks. This difference in BCVA was statistically significant (P< or =0.0001). Seven eyes (23.3%) in the control group had worse vision by > or =2 lines and increased FT by > or =50 microm at 24 weeks, whereas none of the eyes in the IVA group had either worse vision or a significant increase in FT (P = 0.011).

CONCLUSIONS

A single IVA injection given before standard PRP may be beneficial in preventing PRP-induced visual dysfunction and foveal thickening in eyes with severe proliferative diabetic retinopathy and good vision.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Comparison of combination posterior sub-tenon triamcinolone and modified grid laser treatment with intravitreal triamcinolone treatment in patients with diffuse diabetic macular edema

PURPOSE

To compare the efficacy of posterior sub-Tenon's capsule triamcinolone acetonide injection combined with modified grid macular photocoagulation (PSTI + MP) with intravitreal triamcinolone acetonide (IVTA) injection in the treatment of diffuse diabetic macular edema (DME).

MATERIALS AND METHODS

Forty eyes of 33 patients with diffuse DME were randomly allocated into either PSTI + MP (20 eyes) or IVTA (20 eyes). Best corrected visual acuity (VA) and foveal thickness were measured.

RESULTS

The ETDRS scores at baseline were 25.2 +/- 13.6 (mean +/- SD) letters in the PSTI + MP group, whereas 21.7 +/- 16.3 letters in the IVTA group. The ETDRS scores improved by 33.2 +/- 15.9, 34.7 +/- 16.6 and 30.9 +/- 19.0 letters in the PSTI + MP group whereas by 30.9 +/- 15.4, 30.1 +/- 17.9 and 31.5 +/- 15.0 letters in the IVTA group at 1, 3, and 6 months after the treatments, respectively. The VA improved significantly at 1 month and 3 months after both treatments (all p < 0.02, paired t-test). The VA improvements were no longer significant at 6 months in either group. There were no statistically significant differences at any time points between the 2 groups (all p > 0.05, Student's t-test). The foveal thicknesses at baseline and 1, 3, and 6 months after the treatments were 382.8 +/- 148.3, 309.1 +/- 131.3, 319.3 +/- 93.3, 340.4 +/- 123.5 microm (mean +/- SD) in the PSTI + MP group vs. 369.1 +/- 123.1, 241.4 +/- 52.3, 277.5 +/- 137.4, 290.2 +/- 127.9microm in the IVTA group, respectively. Pairwise comparisons revealed significant decrease in foveal thickness at 1 month (p = 0.01, paired t-test) for the PSTI + MP group, and at both 1 month (p < 0.001) and 3 months (p = 0.016) for the IVTA group. There were no statistically significant differences at any time points between the 2 groups (all p > 0.05, Student's t-test). In contrast to the PSTI + MP group, where no complications were noted, the elevation of intra-ocular pressure in 3 of 20 eyes (15%) and a significant increase in average cataract grading were observed in the IVTA group.

CONCLUSION

PSTI + MP treatment provides significant improvement of vision in patients with diffuse DME over 3 months, and achieves outcomes comparable to those after IVTA treatment, however, with fewer complications.

Intravitreal Injection of Triamcinolone Acetonide for the Treatment of Refractory Diabetic Macular Edema

A prospective! descriptive! non-comparative pilot study was used to evaluate the efficacy of intravitreal injection of triamcinolone acetonide (TA) for the treatment of patients with refractory diabetic macular edema that had not responded to laser treatment. Forty eyes of 35 patients with visual acuity (VA) < 6/12 were infected with TA 4 mgl 0.1 cc under topical anesthesia. Results were assessed and analyzed using changes in visual acuity (VA), retinal thickness (RT) and macular volume measured by optical coherence tomography (OCT). In 62.85 % of cases the VA improved by more than two Snellen's lines, the initial VA (mean! log MAR) being 0.67 changing to 0.31 after six months (p = 0.008). RT improved in all patients, having the most remarkable improvement in the Macular Volume, with a decrease of 2.7 mm3 at the end of the study (p = 0.009). Both improvement ofVA and RT were more marked during the early follow-up. The most common complication was ocular hypertension (OHT) in 22.5 % of eyes, all of which responded to medical antiglaucoma treatment. Intravitreal injection ofTA looks to be a useful option for the treatment of refractory diabetic macular edema.

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

PURPOSE

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

DESIGN

Interpretive essay.

METHODS

Literature review and interpretation.

RESULTS

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

CONCLUSIONS

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

Intravitreal triamcinolone for diabetic macular edema: comparison of 1, 2, and 4 mg

PURPOSE

To compare the efficacy and safety of different doses of intravitreal triamcinolone (IVTA) in treating eyes with refractory diffuse diabetic macular edema (DME) with cystic changes.

METHODS

Forty-five eyes of 45 patients with diffuse DME were randomized to receive 1, 2, or 4 mg IVTA. Patients were observed for 6 months and changes in best-corrected visual acuity (VA) in Early Treatment Diabetic Retinopathy Study (ETDRS) scores, retinal thickness analyzer (RTA) central macular thickness (CMT), intraocular pressure, and cataract progression were compared among the three groups.

RESULTS

Forty-two patients completed 6 months of follow-up and were included in the analysis. Following IVTA injection, the ETDRS score improved similarly, eight to nine letters, in all three groups at 4 weeks. The standardized CMT improved in all three groups at 4 weeks. This improvement was maintained through 12 and 24 weeks in the 1 and 2 mg groups, but not in the 4 mg group, which was significantly worse than the 1 and 2 mg groups at 12 and 24 weeks (P = 0.01, 0.03, 0.01, and 0.05).

CONCLUSIONS

Regarding eyes with refractory diffuse DME with cystic changes, 4 mg IVTA does not appear to be more effective than 1 or 2 mg IVTA.

Efficacy of intravitreal triamcinolone acetonide for eyes with postvitrectomy diabetic vitreous hemorrhage

Purpose

To evaluate the efficacy of intravitreal triamcinolone acetonide (IVT) for the management of postvitrectomy diabetic vitreous hemorrhage.

Methods

The authors conducted a retrospective study of patients with postvitrectomy diabetic vitreous hemorrhage who were administered 4 mg (0.1 cc) of triamcinolone acetonide ophthalmic suspension. Ocular history, adverse events, BCVA, intraocular pressure, external eye examination, slit-lamp biomicroscopy, fundus examination, B-scan ultrasonography, and fundus photography were assessed on day 1, weeks 1, 2, and 4 and months 2 and 3.

Results

There were 19 eyes of 18 consecutive patients with mean follow-up after IVT injection of 28 weeks. Of the 19 eyes, 17 eyes (89%) experienced clearing of vitreous hemorrhage within 1 to 5 weeks (mean, 1.7 weeks) with visible triamcinolone precipitates along with blood clot in the inferior aspect of fundus. Of these 17 eyes, 12 eyes (63%) maintained vitreous hemorrhage-free condition at last follow-up with a mean visual acuity of 20/63 (range, 20/320 20/25), whereas 5 (29%) developed recurrent vitreous hemorrhage after clearing of vitreous hemorrhage. Vitreous hemorrhage was not cleared in 2 eyes, which required surgical procedures.

Conclusions

IVT injection may be beneficial for clearing recurrent postvitrectomy Diabetic Vitreous Hemorrhage.

Pharmacotherapies for diabetic retinopathy: present and future

Diabetic retinopathy remains a major cause of worldwide preventable blindness. Measures to avoid blindness include medical management (control of blood sugar, blood pressure, and serum lipids) and ocular management (laser photocoagulation and pars plana vitrectomy). Adjunctive pharmacologic therapies (intravitreal triamcinolone acetonide and anti-vascular endothelial growth factor agents) have shown early promise in the treatment of both diabetic macular edema and proliferative diabetic retinopathy. Other medications under investigation include the fluocinolone acetonide implantable device, extended-release dexamethasone implant, oral ruboxistaurin, and intravitreal hyaluronidase.

Intravitreal injection of triamcinolone acetonide for serous macular detachment in a patient with systemic lupus erythematosus

PURPOSE

To report our experience with intravitreal triamcinolone acetonide treatment of serous macular detachment in a patient with active systemic lupus erythematosus (SLE).

METHODS

Interventional case report.

RESULTS

A 38-year-old man who had SLE with bilateral serous macular detachment and retinopathy was treated with a single intravitreal injection of triamcinolone acetonide in one eye and two intravenous injections of a megadose steroid. Serous detachment in the eye injected with intravitreal steroid showed more significant improvement than that in the fellow eye.

CONCLUSION

Our case suggests that intravitreal triamcinolone acetonide injection may be considered for treatment of SLE-related serous macular detachment that does not respond to systemic steroid therapy.

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.

Recurrence of diabetic macular edema after intravitreous injection of triamcinolone following vitrectomy

PURPOSE

To evaluate the effects of intravitreous triamcinolone acetonide (TA) after pars plana vitrectomy (PPV) for diabetic macular edema (DME).

METHODS

We studied a prospective interventional case series. TA was injected intravitreously after PPV in 28 eyes (PPV+TA group). Eyes with DME that met the same criteria and had been treated with PPV alone (29 eyes) were used as controls. The best-corrected visual acuity (VA) and foveal thickness determined by optical coherence tomography were followed up for over 12 months in both groups. Chronological changes of VA and foveal thickness between the groups were evaluated.

RESULTS

In the PPV+TA group, VA had improved at 1 month, but worsened after 3 months. Improvement of foveal thickness was found until 3 months, but not after 6 months. In controls, both VA and foveal thickness continued to improve. The VA of the PPV+TA group was significantly better than that of the controls at 1 and 3 months (P = 0.007 and 0.015, respectively). The foveal thickness of the PPV+TA group was significantly less than that of controls at 1 month (P = 0.0004). These differences became insignificant thereafter, and foveal thickness became significantly worse in the PPV+TA group than in the controls at 12 months (P = 0.0002).

CONCLUSION

Although adjunctive use of TA after PPV for DME improved VA and foveal thickness, the effect was transient and foveal thickness increased significantly compared with the PPV alone group at 12 months postoperatively.

Triamcinolone versus inner-limiting membrane peeling in persistent diabetic macular edema (TIME study): design issues and implications

AIM

Treatment options for persistent diabetic macular edema remain disappointing. ILM peeling and intravitreal triamcinolone have been successfully used in several case series; however, there is no evidence that one of these options is superior for specific groups of patients. The triamcinolone versus ILM peeling in diabetic macular edema study (TIME-study) is designed to investigate the efficacy of these two treatments in patients with persistent diabetic macular edema.

METHODS

Patients with persistent diabetic macular edema are randomised to either the control group (no treatment), ppV + ILM peeling, or triamcinolone (4 mg) injection. One hundred thirty-five patients are to be recruited per group and followed-up for one year. The main endpoints are defined as change in visual acuity (VA) at 12 months compared to baseline and the change in retinal thickness after 3 months follow-up. Secondary endpoints include differences in the functional success and anatomical success and the effect of the treatment on the patient's quality of life. Twelve institutions (28 surgeons) in 3 European countries agreed to contribute to the study.

RESULTS

The design issues and implications of the study are described.

CONCLUSIONS

The TIME study is the first randomised prospective clinical trial to investigate the effectiveness of the two treatment methods. The results of this study should enable physicians to improve therapy and to select cases according to the most promising treatment option.

Indocyanine-green-mediated photothrombosis (IMP) with intravitreal triamcinolone acetonide for macular edema secondary to group 2A idiopathic parafoveal telangiectasis without choroidal neovascularization: a pilot study

BACKGROUND

The purpose of this study was to determine the feasibility, safety and clinical effect of indocyanine green (ICG)-mediated photothrombosis (IMP) combined with intravitreal triamcinolone acetonide (IVTA) in patients with macular edema secondary to idiopathic parafoveal telangiectasis (IPFT) group 2A without choroidal neovascularization (CNV).

METHODS

Nine eyes of six patients that were treated with IMP immediately followed by IVTA at a dose of 4 mg participated in the study. Patients had a mean follow-up of 23.3 months (range 12-36 months). Patients underwent one or two sessions of IMP combined with IVTA ("study group"). An IVTA-only group of 19 eyes from 14 patients with macular edema secondary to IPFT group 2A that underwent an IVTA 4 mg without IMP ("IVTA-only group") was included for comparison. In addition, a matched control group of 40 eyes from 20 patients selected retrospectively from our medical records with macular edema secondary to IPFT group 2A without any therapy was included ("observation group").

RESULTS

The best-corrected visual acuity (BCVA) remained stable in five eyes (55.5%). Four eyes (44.4%) demonstrated improvement of BCVA (> or = two ETDRS lines), and no eyes experienced worsening of visual acuity (> or = two ETDRS lines). A significant decrease in hyperfluorescence was not seen with fluorescein angiography (FA), however optical coherence tomography (OCT) showed a decrease in the size of inner intraretinal hyporeflective spaces or cystic edema. Two (22.2%) eyes developed an increase in intraocular pressure. However, it was medically controlled with topical anti-glaucoma medications. Cataract developed in five eyes (55.5%). Six of nine eyes (66.6%) required one retreatment during the study period. At the last follow-up (mean 21.1 months, range 12-30 months) in the IVTA-only group, 5 (25.3%) eyes improved BCVA, 11 (57.9%) eyes remained within two lines of baseline BCVA and 3 (15.8%) eyes lost BCVA. In the observation group, with similar follow-up, 87.5% of eyes showed either stabilization or deterioration of BCVA over time.

CONCLUSIONS

Combined IMP and IVTA may provide stability or improvement in BCVA and fundus findings in eyes with macular edema secondary to IPFT group 2A without CNV at a minimum follow-up of 12 months.

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.

Objective evaluation of cataract progression associated with a high dose intravitreal triamcinolone injection

PURPOSE

To investigate the progression of cataract after a high dose (25 mg) intravitreal triamcinolone acetonide injection in patients with macular oedema secondary to diabetes and retinal vein occlusion.

METHODS

This prospective interventional case series study included 38 patients (76 eyes) with diabetic retinopathy or retinal vein occlusion diagnosed with clinical examination and fluorescein angiography. The patients were treated with 25 mg IVTA in their one eye with macular oedema and the fellow eyes served as a control. Patients were asked to return the next day and weekly for 1 month and monthly thereafter by 6 months post-operative. The progression of the cataract using photographic evaluation according to the Lens Opacities Classification System III was documented and statistical analysis was done using the Kaplan-Meier survival analysis and the log-rank test.

RESULTS

Among the 38 treated eyes, there was an increase of cataract degree by 1 grade at the end of 6 months in 10 patients. The types of progressed cataract were PSC in seven patients, cortical in six patients, and nuclear sclerosis in one patient. Six months after the injections, there was a significantly higher rate of progression of PSC (P=0.023, log-rank test) and cortical opacities (P=0.011) in the treated group while the progression of nuclear cataract was not significantly different between the treated eye and the control eye.

CONCLUSION

A high-dose (25 mg) intravitreal triamcinolone acetonide injection induces the progression of cortical and posterior subcapsular opacity in patients with diabetic macular oedema and retinal vein occlusion.

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.

Predictive factors for short-term visual outcome after intravitreal triamcinolone acetonide injection for diabetic macular oedema: an optical coherence tomography study

AIM

To evaluate the predictive factors for visual outcome after intravitreal triamcinolone acetonide injection to treat refractory diabetic macular oedema (DME).

METHODS

A retrospective chart review of patients with DME who met the following inclusion criteria was performed: clinically significant diabetic macular oedema, receipt of a 4 mg/0.1 ml intravitreal triamcinolone acetonide injection and an optical coherence tomography (OCT) of the macula performed up to 10 days before injection. All patients received a full ophthalmic examination including best-corrected Snellen visual acuity (VA). The main outcome measure was the mean change in vision 3 months after injection.

RESULTS

Data from 73 eyes of 59 patients were analysed. After a mean follow-up of 324 days, the mean change in vision was -0.075 logarithm of minimum angle of resolution (logMAR) units, with 27.3% improving > or =3 lines, 6.8% declining > or =3 lines and 60.2% remaining stable within 1 line of baseline vision. Statistical analysis was performed using multivariate generalised estimating equations on the basis of data from 52 eyes of 42 patients. Factors associated with an improvement in vision 3 months after injection were worse baseline VA (-0.27 logMAR units/unit increase in baseline VA, p = 0.002) and presence of subretinal fluid (-0.17 logMAR units, p = 0.06). The presence of cystoid macular oedema negatively affected the visual outcome (0.15 logMAR units, p = 0.03). In addition, the presence of an epiretinal membrane (ERM) was associated with less visual improvement. ERM modified the effect of baseline VA as demonstrated by a significant interaction between these two variables (0.34 logMAR units/unit increase in baseline VA, p = 0.04).

CONCLUSIONS

OCT factors and baseline VA can be useful in predicting the outcomes of VA 3 months after intravitreal triamcinolone acetonide injection in patients with refractory DME.

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 Diabetic Macular Edema: A Prospective, Randomized Study

PURPOSE

The aim of this study was to examine the visual outcome of patients receiving an intravitreal injection of triamcinolone acetonide (TA) as treatment of diffuse diabetic macular edema (DDME).

METHODS

This prospective, placebo-controlled, randomized, clinical interventional study included 40 eyes (38 patients) with DDME, with 28 (70%) eyes randomized to treatment and 12 (30%) eyes randomized to receive a placebo injection. Thirty-six (36) (90%) eyes completed the 3-month study visit, and 32 (80%) eyes completed the 6-month study visit. The treatment group received an intravitreal injection of approximately 20 mg of TA.

RESULTS

Visual acuity increased significantly (P < 0.001) in the study group by 3.4 +/- 2.5 Snellen lines. In the control group, visual acuity did not change significantly (P = 0.07) during follow-up. Difference in change of best visual acuity was significant (P < 0.001) between both groups. At 3 months after baseline, 11 (11/26; 42%) eyes and 10 (10/26; 39%) eyes, respectively, improved by at least 2 and 3 lines, respectively, in the study group, versus 2 (2/10; 20%) eyes and 1 (1/10; 10%) eye in the control group. At 6 months after baseline, 11 (11/23; 48%) eyes and 9 (9/23; 39%) eyes, respectively, improved by at least 2 and 3 lines, respectively, in the study group, versus 0 (0%) eyes and 0 (0%) eyes in the control group. The difference was significant for the 2-line improvement (P = 0.01) and 3-line improvement (P = 0.03).

CONCLUSIONS

Using a dosage of approximately 20 mg of intravitreal TA, visual acuity temporarily increases for 6 months after injection.

The effect of posterior subtenon methylprednisolone acetate in the refractory diabetic macular edema: a prospective nonrandomized interventional case series

Background

To investigate the efficacy of posterior subtenon methylprednisolone acetate injection in treatment of refractory diffuse clinically significant diabetic macular edema (CSME).

Methods

In a prospective, nonrandomized, interventional case series, 52 eyes were diagnosed with CSME and treated with at least two sessions of laser photocoagulation according to Early Treatment Diabetic Retinopathy Study guidelines. At least 3 months after laser therapy, eyes with a residual central macular thickness were offered posterior subtenon injection of 40 mg methylprednisolone acetate. Main outcome measures were visual acuity, macular thickness and intraocular pressure. Potential complications were monitored, including intraocular pressure response, cataract progression and scleral perforation.

Results

Mean baseline visual acuity (in logMAR) improved significantly (p = 0.003) from 0.8 ± 0.36 to 0.6 ± 0.41 at 3 months. Mean foveal thickness decreased from 388 ± 78 μm at baseline to 231 ± 40 μm after 3 months (p < 0.0001). Visual acuity improvement in eyes with CSME with extrafoveal hard exudates was significant (p = 0.0001), but not significant in eyes with CSME with subfoveal hard exudates (p = 0.32). Intraocular pressure increased from 14.7 ± 2.0 mmHg (range, 12–18 mmHg) to a maximum value of 15.9 ± 2.1 mmHg (range, 12–20 mmHg) during the follow-up period. Complications in two eyes developed focal conjunctival necrosis at the site of injection.

Conclusion

Posterior subtenon methylprednisolone acetate may improve early visual outcome in diffuse diabetic macular edema that fails to respond to conventional laser photocoagulation. Visual acuity improvement in eyes with CSME with extrafoveal hard exudates was significant; and this improvement is depends on location of hard exudates. Further study is needed to assess the long-term efficacy, safety, and retreatment.