Intravitreal triamcinolone prior to laser treatment of diabetic macular edema: 24-month results of a randomized controlled trial

Abstract

Purpose: To report the 24 months outcomes from a clinical trial of intravitreal triamcinolone acetonide (IVTA) plus laser versus laser treatment only in eyes with diabetic macular edema (DME).

Design: Prospective, double-masked, randomized, placebo-controlled study.

Participants: Eighty-four eyes of 54 participants were entered into the study, with 42 eyes randomly assigned to receive IVTA plus laser and 42 randomly assigned to receive laser treatment alone. Primary end point data were available for 71 (84.5%) eyes at 24 months, with last visual acuity observation carried forward for the remaining eyes.

Methods: Best-corrected logarithm of minimum angle of resolution (logMAR) visual acuity and central macular thickness (CMT) by optical coherence tomography were measured after laser treatment preceded by either IVTA or sham.

Main outcomes measures: The primary outcome was the proportion of eyes with improvement in visual acuity of 10 letters or more at 24 months. The secondary outcomes were mean visual acuity, requirement for further treatment, change in CMT, and adverse events.

Results: At 24 months, improvement of 10 logMAR letters or more was seen in 15 (36%) of 42 eyes treated with IVTA plus laser compared with 7 (17%) of 42 eyes treated with laser only (P = 0.047; odds ratio, 2.79; 95% confidence interval, 1.01-7.67). There was no difference in the mean CMT or mean logMAR visual acuity between 2 groups. At least 1 retreatment was required in the second year of the study in 29 (69%) of 42 IVTA plus laser-treated eyes compared with 19 (45%) of 42 laser only eyes (P = 0.187). Cataracts were removed from 17 (61%) of 28 phakic IVTA plus laser-treated eyes versus 0 (0%) of 27 laser only eyes (P<0.001). Treatment for elevated intraocular pressure was required in 27 (64%) of 42 IVTA plus laser eyes compared with 10 (24%) of 42 laser only eyes (P<0.001).

Conclusions: Treatment with IVTA plus laser resulted in a doubling of improvement in vision by 10 letters or more compared with laser only over 2 years in eyes with DME, but is associated with cataract and raised intraocular pressure.