Although PDT is effective in closing the choroidal neovascularization in FVT, this technique was ineffective in occluding anastomotic vessels and their associated tributaries within the mid- to proximal retina. Various factors (vascular diameter, composition, blood flow, orientation) may contribute to continued anastomotic patency. By convention, such vessels would typically be defined as chorioretinal anastomoses (CRAs); however, continuing studies suggest the possibility that these neovessels constitute dual-origin hybrids. Regardless of origin, viable anastomoses provide one potential mechanism for revascularization to occur after PDT and may help to explain why CRAs are considered a poor prognostic sign in patients with AMD.