A system provides a roadmap image displaying a vessel structure using an imaging system to acquire data representing multiple temporally sequential individual images of vessels of a region of interest of patient anatomy in the presence of a contrast agent. An image data processor generates multiple sequential cumulative images corresponding to the individual images and an individual current cumulative image corresponds to a current image of the individual images. The current cumulative image comprises cumulative pixel luminance values and an individual cumulative pixel luminance value is generated from luminance values of pixels, spatially corresponding to the individual cumulative pixel and present in images comprising a subset of the individual images. The subset comprises contiguous images of the temporally sequential individual images acquired preceding the current image and including the current image. An output processor provides the multiple sequential cumulative images to a destination.