MyVisionTest News Archive
Oct 19, 2009
Visual acuity after intravitreal triamcinolone for diabetic macular edema
A meta-analysis of the literature finds that intravitreal triamcinolone (steroid injection) in patients with diabetic macular edema (DME) that fails to respond to laser photocoagulation treatment results in 3 lines of visual acuity improvement 1 month after injection, but this benefit gradually decreases to baseline by 6 months.
Macular edema is the most common cause of reduced visual acuity in diabetic retinopathy, which in turn is the leading cause of blindness in North America. The treatment of macular edema, standardized by the Early Treatment Diabetic Retinopathy Study (ETDRS), demonstrated that focal laser treatment reduces the risk of moderate visual loss (3 or more lines of visual acuity) from 24% to 12%. Unfortunately, not all patients respond to focal laser treatment, stimulating the investigation of other treatments such as grid laser photocoagulation, pars plana vitrectomy, antivascular endothelial growth factor therapy, and intravitreal triamcinolone.
Methods and Results
The current study was designed to quantify the effect on visual acuity of intravitreal triamcinolone for the treatment of laser-refractory diabetic macular edema (DME).
A search for eligible studies on MEDLINE, EMBASE, the Cochrane Library, and Google uncovered 7 randomized controlled trials and 3 cohort studies. Studies that evaluated the efficacy of triamcinolone for the treatment of DME refractory to laser photocoagulation, reported visual acuity data, and compared the intervention with an appropriate control group were included. Exclusion criteria were studies of non-DME, triamcinolone used as an adjunct to another treatment, and triamcinolone delivery other than intravitreally.
Using a random-effects model, there was a statistically significant summary mean difference in visual acuity of -0.313 logarithm of the minimum angle of resolution (logMAR) units (95% CI -0.551, -0.074) after 1 month of follow-up. This difference declined to -0.125 logMAR units (95% CI -0.181, -0.070) by 3 months and to -0.043 logMAR units (95% CI -0.090, 0.003) by 6 months. No evidence of publication bias was present. There was a high level of heterogeneity in this group of studies (meta-analysis of 1-month follow-up data: Q-statistic = 21.987, p< 0.001), attributable primarily to study design.
Discussion and Conclusions
This meta-analysis focused on the quantification of visual improvement from intravitreal triamcinolone. The effect of treatment is temporary: patients, on average, will realize 3 lines of visual improvement 1 month postinjection, declining to 1 line of visual improvement after 3 months, and returning to baseline by 6 months. In this subset of patients, this may still be a useful treatment should the visual improvement lead to a functional benefit (such as recovery of driving vision).
The investigators conclude that intravitreal triamcinolone results in a temporary improvement of visual acuity in patients with laser-refractory DME, with a peak benefit of approximately 3 lines of visual acuity 1 month postinjection.
Read more...
Can J Ophthalmol. 2009 Oct;44(5):587-93
Tags: diabetes, macular edema, steroid
A meta-analysis of the literature finds that intravitreal triamcinolone (steroid injection) in patients with diabetic macular edema (DME) that fails to respond to laser photocoagulation treatment results in 3 lines of visual acuity improvement 1 month after injection, but this benefit gradually decreases to baseline by 6 months. Macular edema is the most common cause of reduced visual acuity in diabetic retinopathy, which in turn is the leading cause of blindness in North America. The treatment of macular edema, standardized by the Early Treatment Diabetic Retinopathy Study (ETDRS), demonstrated that focal laser treatment reduces the risk of moderate visual loss (3 or more lines of visual acuity) from 24% to 12%. Unfortunately, not all patients respond to focal laser treatment, stimulating the investigation of other treatments such as grid laser photocoagulation, pars plana vitrectomy, antivascular endothelial growth factor therapy, and intravitreal triamcinolone.
The current study was designed to quantify the effect on visual acuity of intravitreal triamcinolone for the treatment of laser-refractory diabetic macular edema (DME).
A search for eligible studies on MEDLINE, EMBASE, the Cochrane Library, and Google uncovered 7 randomized controlled trials and 3 cohort studies. Studies that evaluated the efficacy of triamcinolone for the treatment of DME refractory to laser photocoagulation, reported visual acuity data, and compared the intervention with an appropriate control group were included. Exclusion criteria were studies of non-DME, triamcinolone used as an adjunct to another treatment, and triamcinolone delivery other than intravitreally.
Using a random-effects model, there was a statistically significant summary mean difference in visual acuity of -0.313 logarithm of the minimum angle of resolution (logMAR) units (95% CI -0.551, -0.074) after 1 month of follow-up. This difference declined to -0.125 logMAR units (95% CI -0.181, -0.070) by 3 months and to -0.043 logMAR units (95% CI -0.090, 0.003) by 6 months. No evidence of publication bias was present. There was a high level of heterogeneity in this group of studies (meta-analysis of 1-month follow-up data: Q-statistic = 21.987, p< 0.001), attributable primarily to study design.
Discussion and Conclusions
This meta-analysis focused on the quantification of visual improvement from intravitreal triamcinolone. The effect of treatment is temporary: patients, on average, will realize 3 lines of visual improvement 1 month postinjection, declining to 1 line of visual improvement after 3 months, and returning to baseline by 6 months. In this subset of patients, this may still be a useful treatment should the visual improvement lead to a functional benefit (such as recovery of driving vision).
The investigators conclude that intravitreal triamcinolone results in a temporary improvement of visual acuity in patients with laser-refractory DME, with a peak benefit of approximately 3 lines of visual acuity 1 month postinjection.
Read more...
Can J Ophthalmol. 2009 Oct;44(5):587-93
