Effect of Intravitreal Triamcinolone Acetonide or Bevacizumab on Choroidal Thickness in Eyes With Diabetic Macular Edema

PURPOSE. We evaluated the effect of intravitreal triamcinolone acetonide (IVTA) or intravitreal bevacizumab (IVB) on subfoveal choroidal thickness (SFCT) in eyes with diabetic macular edema (DME). METHODS. In this prospective, randomized, interventional comparative study, 51 DME eyes of 51 patients were randomized to receive either IVTA or IVB. The central macular thickness (CMT) and SFCT were determined by optical coherence tomography at 24 hours, 7 days, and 4, 8, and 12 weeks. The SFCT at 1500 and 3000 mu m nasal or temporal to the central fovea also was measured. The values obtained before were compared to those obtained 12 weeks after the injections. RESULTS. The eyes were randomly assigned to the IVTA (25 eyes) and IVB (26 eyes) groups. The SFCT was reduced significantly in the IVTA group from 24 hours to 12 weeks. The average +/- SD of the SFCT expressed as the ratio to baseline thickness decreased to 94.8% +/- 5.6% (P < 0.01) at 24 hours after IVTA and remained unchanged up to 12 weeks (91.8% +/- 10.5%, P < 0.01, Wilcoxon signed-rank test). In the IVB group, no significant difference was found in the SFCT after IVB for 12 weeks. The CMT decreased significantly in both groups from 24 hours to 4 weeks; however, the decrease was not significant at 8 weeks or later in the IVB group. CONCLUSIONS. The decrease in choroidal thickness in eyes with DME after IVTA suggests that the choroidal pathology in diabetic retinopathy might be due to steroid-sensitive factors rather than vascular endothelial growth factor. (www.umin.ac.jp/ctrnumber, clinical trials number UMIN000009854.)