Visual Acuity after 3 Intial Injections of Intravitreal Ranibizumab in the Management of Diabetic Macular Edema

摘要

Purpose: : To determine change of best corrected visual acuity (BCVA) and anatomic effects of 3 initial intravitreal injections of ranibizumab followed by a pro re nata (PRN) dosing regimen in patients with clinically significant diabetic macular edema (CSME). Methods: : 15 eyes of 9 patients (mean age, 67,1 years [range, 41-78]) with center-involving CSME were treated with 3 monthly intravitreal injections of 0,5 mg ranibizumab followed by a PRN reinjection regimen. Follow-up in all patients was 6 months.Analysis included the mean change from baseline BCVA and change from baseline mean foveal thickness (FTH) defined as center subfield thickness.Reinjections after week 12 were performed upon signs of disease activity as defined by increase of mean foveal thickness (FTH) determined by SD OCT or loss of best-corrected visual acuity (BCVA). Results: : The baseline mean BCVA was 0,32?±0,22 and the mean FTH was 505?±210 ??m. Mean HbA1c was 6,4?±0,4. At month 3 after 3 intravitreal injections of ranibizumab mean BCVA was 0,38?±0,21 (p=1,0) and mean FTH was 333?±135 ??m (p=0,139). At month 6 mean BCVA was 0,31?±0,21 (p=1,0) and mean FTH was 385?±143 ??m (p=0,019). The mean number of reinjections between month 4 and 6 was 0,43?±0,51 resulting in a mean total of 3,43?±0,51 injections per study eye. None of the study eyes received more than 1 reinjection and 60% of all study eyes only received the initial 3 injections of ranibizumab. Conclusions: : In this series a regimen with 3 initial intravitreal injections of ranibizumab followed by PRN reinjections resulted in overall stabilization of BCVA. Despite a favorable morphological response as shown by reduction of mean FTH no statistically significant gain in BCVA could be achieved.This may indicate that a PRN regimen does not prove an equivalent alternative to a fixed-dosing schedule in the treatment of diabetic macular edema.