Macular Structure and Function After Intravitreal Triamcinolone Acetonide for Diffuse Diabetic Macular Edema: A Pilot Study Including OCT and Focal ERG

Abstract

Abstract: : Purpose: To assess macular structure and function by optical coherence tomography (OCT) and focal electroretinogram (FERG) before and after intravitreal Triamcinolone Actenoide (IVTA) admnistration for diffuse diabetic macular edema (DDME). Methods: Eleven patients (mean age 56, range 44–68 yrs) with bilateral DDME refractory to laser treatment were longitudinally evaluated before and after IVTA by serial clinical, OCT and FERG measurements over a mean follow–up period of 12 weeks (range 9–15). Macular retinal thickness was determined by the standard OCT Stratus algorithm. FERGs were recorded in response to an 18 degrees flickering stimulus modulated sinusoidally at 41 Hz. Response amplitude and phase were monitored. The fellow uninjected eyes of patients served as controls. Results: Compared to baseline, mean retinal thickness decreased (by 0.37 log units, SE: 0.05, p < 0.01) and mean FERG amplitude, but not phase increased (by 0.14 log units, SE: 0.06, p < 0.05) at the end of follow–up. Visual acuity improved by 0.145 log units (SE: 0.04, p < 0.05). No correlation was found between OCT and FERG changes in individual patients. Test–retest changes of both OCT and FERG measures obtained from the fellow control eyes were non significant and smaller (p < 0.05) than those found in treated eyes. Conclusions: Results indicate that IVTA induces short–term beneficial changes in both macular structure and function in eyes with DDME, and suggest that this treatment is avoid of toxic effects on the outer neural retina.

Keywords: diabetic retinopathy • electroretinography: clinical • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)