Abstract
Purpose: :
To evaluate the initial anatomic results via optical coherence tomography (OCT) of intravitreal injection of ranibizumab for neovascular age-related macular degeneration (AMD) and to compare it to changes in visual acuity.
Methods: :
37 eyes of 37 patients enrolled in the SAILOR trial were randomized to treatment with monthly intravitreal injections of either 0.3mg or 0.5mg of ranibizumab. Visual acuity was measured with Early Treatment of Diabetic Retinopathy Study (ETDRS) eye charts, and Stratus OCT central subfield thickness (central 1000-µm diameter circle) measurements were obtained. Anatomic improvement was characterized in terms of absolute change in central subfield thickness and standardized change in macular thickening (SCMT). "Anatomic success" was defined as an OCT central subfield thickness ≤252 µm (mean for a normal population = 212±20 µm).
Results: :
Mean values at baseline for the patients were 337.4±113.6 µm for central subfield thickness and 55.9±12.7 letters for visual acuity. At 3 months 34 of 37 (91.9%) patients had an absolute reduction in central subfield thickness. The mean central subfield thickness at 3 months differed significantly from baseline (220.1±61.8 µm, P<0.001). Mean visual acuity at 3 months also differed significantly from baseline (59.2±16.0 letters, P = 0.016). 5 of 37 (13.5%) patients gained ≥10 letters’ best corrected visual acuity (BCVA), and 18 of 37 (48.6%) patients gained ≥5 letters’ BCVA. However, there was no correlation between central subfield thickness reduction and improvement in visual acuity at 3 months (Pearson r = 0.015, r2 = 0.000, P = 0.929). 31 patients had an initial central subfield thickness >252 µm. At 1 month, 18 of these patients (58.1%) had achieved "anatomic success," and at 3 months, 23 (74.2%) patients had achieved "anatomic success." Mean SCMT for this subset of patients was 58.2±51.2% at 1 month, and 90.6±45.9% at 3 months.
Conclusions: :
Monthly 0.3 or 0.5 mg intravitreal injections of ranibizumab produced a statistically significant reduction in mean central subfield thickness as well as a statistically significant improvement in mean visual acuity in patients with neovascular AMD at 3 months. Over this time frame, however, there was no significant correlation between the two parameters. Clinicians often base treatment decisions on quantitative OCT data. This study provides a definition of "anatomic success" that in conjunction with SCMT measurements may help to guide treatment decisions and serve as a baseline for comparing different treatment regimens.
Clinical Trial: :
www.clinicaltrials.gov NCT00251459
Keywords: age-related macular degeneration • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials • imaging/image analysis: clinical