RESUMEN
Purpose: to evaluate the effects of posterior subtenon triamcinolone acetonide [TA] injection on clinical, angiographic, and optical coherence tomographic [OCT] features in refractory diabetic macular edema [DME]
Method: in a randomized double-masked placebo-controlled clinical trial, 38 consecutive patients [64 eyes] with DME refractory to previous laser therapy or not suitable for such treatment were studied. An equal number of eyes [32] were allocated in the treatment and control groups. Posterior subtenon injection of 40 mg TA in the treatment group and subconjnctival injection of 0.1 ml of lidocaine 2% in the control group was performed and repeated after two months. Clinical, angiographic, and OCT features were evaluated before intervention and after 4 months. Quantitative measurement of hard exudates [HE], size of foveal avascular zone [FAZ], and leakage was done using Photoshop 7-0 software
Results: before injection, best corrected visual acuity [BCVA] was 0.93 +/- 0.39 LogMAR in the control group and 0.75 +/- 0.38 LogMAR in the treatment group [P= 0.078]. At the last follow up, BCVA was 0.88 +/- 0.48 LogMAR in the control group and 0.71 +/- 0.42 LogMAR in the treatment group [P= 0.136]. Before injection, central macular thickness [CMT] was 388.2 +/- 119.1 [micro]m in controls and 392.2 +/- 153.6 [micro]m in cases [P= 0.9]. At the end of the study, CMT was 375.4 +/- 154.66 [micro]m and 377.37 +/- 180.04 [micro]m in cases and controls, respectively [P= 0.5]. There was also no significant difference in HE, FAZ, and leakage changes in the angiograms. In 2 eyes of the treatment group, intraocular pressure exceeded 20 mmHg which was controlled by medication
Conclusion: posterior subtenon injection of TA in the eyes with severe DME seems to have no effect on visual acuity and macular thickness