Comparison of intravitreal triamcinolone and posterior subtenon triamcinolone in diffuse diabetic macular edema

Aim: To assess the efficacy and complications of the intravitreal injection of Triamcinolone Acetonide (IVTA) as compared to posterior subtenon injection of triamcinolone (PST) for the treatment of diabetic macular edema. Materials and Methods: Twenty four patients with type II diabetes, having diabetic retinopathy with macular edema were recruited. One eye of each patient was assigned to 4mg IVTA and the other eye was given 40 mg PST. Before and one, three and six months after treatment we measured visual acuity as well as thickness of the macula, with optical coherence tomography (OCT), and intraocular pressure (IOP). Results: In the IVTA group, a reduction in foveal thickness of 150µ was observed (p = 0.012) at 3 months compared to baseline. A reduction of around 70 microns was observed in the PST group which was not statistically significant (p = 0.290). In the IVTA group, the mean visual acuity increased from 1.048+/-0.512 at baseline to 0.707+/-0.552 at 6 months, which was statistically significant (p = 0.001). In the PST group, the mean visual acuity improved from 0.797 +/-0.425 at baseline to 0.727 +/-0.448 after 6 months with visual improvement maintained in 9 eyes (45%) throughout the study period. IOP rise in IVTA group was not statistically significant; whereas, in the PST group it became statistically significant. However, IOP rise lost its significance at 6 months (p = 0.09) owing to treatment with anti-glaucoma medications. Conclusion: Both IVTA and PST can be used as effective treatment options for diabetic macular edema.