Suprachoroidal versus Intravitreal Triamcinolone Acetonide for the Treatment of Diabetic Macular Edema

PURPOSE: This article aims to compare between intravitreal (IV) and suprachoroidal (SC) triamcinolone acetonide (TA) injection for the treatment of diabetic macular edema (DME) in terms of improvement in both best-corrected visual acuity (BCVA) and central macular thickness (CMT), and development of complications (intraocular pressure (IOP) rise and cataract progression), and to identify the efficient dose of TA using the SC route. PATIENTS AND METHODS: This prospective interventional randomized comparative study included 45 eyes of 32 patients, randomly divided into three groups, group I received 4 mg/0.1 mL intravitreal TA (IVTA), group II received 4 mg/0.1 mL suprachoroidal TA (SCTA), and group III received 2mg/0.1 mL SCTA. Patients were followed up for 6 months. RESULTS: At 1 month, a maximum reduction in CMT (147.33 ± 110.97 µm, 160.80 ± 98.25 µm and 65.64 ± 46.19 µm in groups I, II, and III, respectively) was observed, which was associated with the greatest improvement of BCVA (0.09 ± 0.09, 0.19 ± 0.10 and 0.10 ± 0.09 logMAR lines) in groups I, II, and III, respectively. At 3 months, CMT started to increase, and reduction was not statistically significant compared to baseline, except in group II (4 mg SCTA group) (149.80 ± 106.57 µm with P-value = 0.013). At 6 months, CMT and BCVA returned close to baseline except for group II which had a sustained reduction of 60.16 µm from baseline. Regarding steroid-related complications, IOP elevation of 10 mmHg or more was noted in 1 eye (6.7%), 2 eyes (13.3%), and 1 eye in groups I, II, and III, respectively. Three phakic eyes per group showed cataract progression. CONCLUSION: SCTA is a safe and effective route for the treatment of DME, which has comparable effects to IVTA, and may even last longer.