Effects of repeated injection of intravitreal triamcinolone on macular oedema in central retinal vein occlusion

Abstract

To investigate the effectiveness of repeated injections of intravitreal triamcinolone acetonide (IVTA) in the treatment of macular oedema caused by central retinal vein occlusion (CRVO). Seventeen pseudophakic or aphakic eyes of 17 patients (10 male, seven female) with macular oedema caused by CRVO received a repeat injection of 4 mg IVTA, 16 weeks after the first injection of the same dose. The examination included measurements of best-corrected visual acuity (BCVA) for distance and central foveal thickness (CFT) by optical coherence tomography (OCT), preoperatively and 1, 2, 3 and 4 months postoperatively. The values were compared by paired-t test. Side-effects were monitored. BCVA and CFT were not significantly different before initial and repeat injections. Transient improvements of BCVA and CFT were achieved after both injections. At the end of follow-up, BCVA and CFT were significantly different compared to pre-injection values in the same group (P = 0.032, 0.049 in the initial-injection group and P = 0.001, 0.008 in the repeat-injection group, respectively). However, compared to the initial injection, BCVA measurements were significantly worse at each time-point (P = 0.043, 0.011, 0.010 and 0.012, respectively) after the repeat injection, as were CFT at 1, 2 and 3 months post-injection (P = 0.040, 0.015 and 0.025, respectively). The achieved maximum mean intraocular pressures were 20.00 [standard deviation (SD) 2.06] mmHg and 18.56 (SD 3.65) mmHg after the first and repeat injections, respectively. These values were not significantly different (P = 0.467). No other significant adverse events were noted during the study. A repeat injection of 4 mg IVTA may not be as effective as an initial injection for the treatment of macular oedema caused by CRVO.