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

Abstract

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) microm at baseline to 277.46 (96.77) microm, 255.33 (95.73) microm, and 331.25 (146.76) microm 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.

Figure 1

Diagram showing log MAR visual acuity before and 1 month after the first intravitreal injection of 4 mg of triamcinolone acetonide.

Figure 2

Diagram showing OCT macular thickness before and 1 month after the first intravitreal injection of 4 mg of triamcinolone acetonide.

Figure 3

Graphic representation of the change in visual acuity as a function of total follow up time.

Figure 4

A 69 year old diabetic man with reduced visual acuity in the right eye to the level of 0.1 secondary to diffuse diabetic macular oedema. He had two previous laser treatments in the right eye. Intravitreal triamcinolone acetonide 4 mg in 0.1 ml was injected one time in the right eye. (A) Clinical fundus photograph of the right eye at baseline demonstrated the presence of background diabetic retinopathy. There was diffuse macular oedema, hard exudates, and intraretinal haemorrhages at the posterior pole. The white line represents the area scanned with the OCT. (B) OCT cross section scan through the macula confirmed the presence of macular oedema. There were intraretinal fluid filled cystoid spaces and serous elevation of the neurosensory retina. The macular thickness in the fovea measured by OCT was 557 μm. (C) False colour topographic map of the macula demonstrated diffuse macular thickening. In the false colour map white corresponds to the area of maximal thickening and blue corresponds to the less thick areas. (D) One month after IVTA the visual acuity had improved to 0.2. The central macular thickness was decreased to 461 μm. OCT scan through the macula demonstrated slight resolution in the macular oedema. (E) False colour topographic map of the macula demonstrated some reduction in retinal thickness especially in the inferonasal macula. (F) Three months after IVTA visual acuity had improved to 0.32. There was partial resolution of the serous neurosensory detachment in the macula by OCT. (G) False colour topographic map of the macula confirmed the partial resolution of the macular oedema. There was still thickening temporally (white). (H) Clinical photograph of the same eye 6 months after IVTA revealed resolution of the macular oedema and reduction in the number of hard exudates at the posterior pole. Visual acuity had improved to 0.4. The white line represents the area scanned with the OCT. (I) OCT scan through the fovea demonstrated almost total resolution of the serous neurosensory macular elevation. There was also disappearance of the intraretinal cystoid spaces. Central macular thickness was 173 μm. (J) False colour topographic map confirmed the presence of diffuse flattening of the macula.

Figure 5

(A) High magnification clinical photograph at baseline of the same patient in figure 3 demonstrated the presence of hard exudates in the macula. (B) High magnification clinical photograph 6 months after IVTA of the same eye revealed marked resolution in the presence of hard exudates in the macula.