Quantified anastomotic areas of neovascularization as factors associated with frequent recurrence in neovascular age-related macular degeneration.

Abstract

To investigate the quantitative characteristics of anastomoses of macular neovascularization (MNV) in neovascular age-related macular degeneration (nAMD) using optical coherence tomography angiography (OCTA) according to the frequency of intravitreal injections (IVIs). Eighty-six eyes of 86 patients treated for nAMD were classified into two groups based on the number of IVIs administered over 12 months: stable (<3) and unstable (≥3). Anastomotic areas were defined as areas surrounded by neighboring vessels in the MNV; their total number, mean area, maximal and minimal diameters (i.e., maximal and minimum Feret diameters), and ratio (Feret aspect ratio [AR]) were analyzed in the inner and outer areas of the MNV. Forty-four and 42 eyes were classified into the stable and unstable groups, respectively. The eyes in the unstable group had larger anastomotic areas with longer minimum Feret diameters and higher perimeters in the outer MNV. In the logistic regression analysis, instability was associated with a larger anastomotic area and a larger minimum Feret diameter in the outer MNV. Multivariate analysis revealed that a larger minimum Feret diameter in the outer MNV was the most significant factor (P=0.03). The quantitative characteristics of the anastomotic areas in the MNV might indicate the need for IVIs in nAMD patients.