Abstract
Abstract: :
Purpose: To evaluate the changes in central retinal thickness as measured by Stratus OCTTM imaging following systemic bevacizumab (Avastin®, Genentech Inc.) therapy in patients with subfoveal choroidal neovascularization (CNV) secondary to age–related macular degeneration (AMD). Methods: AMD patients with subfoveal CNV, a central retinal thickness of at least 300 microns, and visual acuity from 20/40 to 20/400 were enrolled in a prospective, open–label, single–center clinical study. They were treated initially with 2 or 3 infusions of bevacizumab (5mg/kg) at 2 week intervals. Patients were examined every week for the first 6 weeks, every 2 weeks for the next 6 weeks, and every 4 weeks thereafter. At baseline and at each follow–up visit, patients underwent imaging using the Stratus OCTTM. The OCT outcomes included the change in central retinal thickness over time and the correlation between the changes in central retinal thickness measurements and the changes in visual acuity letter scores. Results: Of the 15 patients enrolled in the study, 9 patients have been followed for at least 3 months. At 3 months, the median and mean central retinal thickness measurements of these first 9 Study Eyes decreased by 157µm (p=0.008) and 177µm (p=0.001), respectively. One week after the first dose, statistically significant changes in the central retinal thickness measurements were evident. In the 9 Fellow Eyes, CNV was diagnosed in 8 eyes at baseline, and 5 eyes were evaluable using OCT. In these 5 Fellow Eyes, median and mean central retinal thickness measurements decreased by 59µm (p=0.028) and 92µm (p=0.06), respectively. When all the eyes were evaluated at 3 months, there was a statistically significant relationship between the decrease in central retinal thickness and the increase in visual acuity measurements (r = 0.7; p = 0.004). When evaluated separately, the correlation for the Study Eyes was good and trending towards significance, but not statistically significant (r=0.61, p=0.08), while the correlation for the Fellow Eyes was statistically significant (r=0.93, p=0.006). Conclusions: Bevacizumab therapy resulted in restoration of the macular contour as assessed by OCT. The decrease in central retinal thickness measurements correlated with improvements in visual acuity. These changes were evident within 1 week of initial treatment. Follow–up is ongoing to determine the durability of these favorable OCT outcomes.
Keywords: choroid: neovascularization • age-related macular degeneration • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled