In the present invention, an imaging system and method for providing contrast-enhanced X-ray images of tissue includes an energy source in communication with a detector operable to generate radiological images of the tissue injected with the contrast agent, a display and a computer connected to the display and to receive the acquired images from the detector. The system is operable to acquire a number of first images of the contrast agent in the tissue, wherein the number of first images are single energy images, and a number of second images corresponding to the number of first images, wherein the second images are each a single energy image with an energy level opposite that for the first images. The first and second images are combined to generate a contrast-enhanced image with reduced exposure of the tissue and reduced time for completion of the procedure.