Evaluation of choroidal neovascularization with indocyanine green angiography in neovascular age-related macular degeneration subjects undergoing intravitreal bevacizumab therapy

Abstract

Purpose: To report the clinical implications of interval changes in choroidal neovascularization (CNV) size measured by indocyanine green (ICG) angiography in neovascular age-related macular degeneration (AMD) patients undergoing intravitreal bevacizumab therapy.

Design: Retrospective, consecutive chart review.

Methods: The charts of neovascular AMD patients who underwent intravitreal bevacizumab therapy using a treat-and-extend dosing schedule were reviewed. ICG angiographic CNV surface areas were measured at baseline, 2 months, 6 months, and 12 months in each subject. The primary outcome was change in CNV size. Secondary outcomes included the correlation of change in CNV surface area with change in best-corrected visual acuity (BCVA), change in central macular thickness on optical coherence tomography (OCT), and the number of injections delivered over the 12-month study interval.

Results: A total of 123 subjects were included in the analysis. The baseline CNV size was 1.9 mm2±2.5 mm2. CNV size was 1.66 mm2±2.11 mm2 at 2 months, 1.60 mm2±2.23 mm2 at 6 months, and 1.50 mm2±2.12 mm2 at 12 months. The change in CNV size from baseline was not statistically significant at any of the follow-up intervals. A decrease in CNV size of 33% or more at 2 months was associated with a significant decrease in CNV size at 12 months (P=.0096), complete resolution of CNV at 12 months (P=.0013), and a decrease in the number of injections delivered over the study interval (P=.0165). Complete resolution of CNV at 12 months occurred in 7.3% of subjects. Subjects that had complete resolution of CNV at 12 months were significantly more likely to gain 3 more lines of BCVA at the end of the study interval (P=.0131). No significant correlation was found between CNV size and change in central macular thickness on OCT.

Conclusions: Our study suggests that change in CNV size on ICG angiography may help the clinician predict the clinical course of neovascular AMD subjects undergoing intravitreal bevacizumab therapy using a treat-and-extend dosing schedule.