SCIENTIFIC REPORT Intravitreal triamcinolone for the treatment of refractory diabetic macular oedema with hard exudates: an optical coherence tomography study

Aim: To investigate the use of intravitreal triamcinolone acetonide (IVTA) for the treatment of diabetic macular oedema (DMO) unresponsive to previous laser photocoagulation. Method: A retrospective, interventional, non-comparative case series. There were 30 eyes of 22 consecutive patients with refractory DMO. An intravitreal injection of triamcinolone acetonide at the dose of 4 mg in 0.1 ml was administered. Best corrected visual acuity was measured at each examination. In addition the central macular thickness was quantitatively measured by optical coherence tomography (OCT) examination at each visit. The amount of hard exudates deposition in the macula was subjectively evaluated using colour fundus photographs. Results: 30 eyes of 22 patients completed 6 months or more of follow up and were included in the study. Mean (SD) visual acuity improved from 0.17 (0.12) at baseline to 0.34 (0.18), 0.36 (0.16), and 0.31 (0.17) at the 1, 3, and 6 month follow up respectively. Mean (SD) OCT macular thickness decreased from 476 (98.32) mm at baseline to 277.46 (96.77) mm, 255.33 (95.73) mm, and 331.25 (146.76) mm at the 1, 3, and 6 month follow up period respectively. 18 and seven eyes completed 12 months and 18 months of follow up, respectively. Mean (SD) visual acuity was 0.36 (0.15) and 0.35 (0.16) at the 12 and 18 month follow up period respectively. 12 eyes received two, seven eyes received three, and two eyes received four IVTA injections. The mean (SD) interval between the first and second IVTA injection was 5.7 (2.67) months and between the second and third was 5.7 (3.25) months. Hard exudates were present in the macula at baseline in all eyes. Progressive reduction in the number and size of the hard exudates was noted after IVTA in all cases. Intraocular pressure was raised above 21 mm Hg in 12 (40%) of 30 eyes. Two eyes developed posterior subcapsular cataract and two developed vitreous haemorrhage. Conclusions: IVTA is a promising treatment for patients with DMO refractory to laser treatment. IVTA is effective in improving vision, reducing macular thickness, and inducing reabsorption of hard exudates. Further investigation is warranted to assess the safety of IVTA for the treatment of DMO.