A method for tracking images of a blood vessel wherein user indication of the source and terminus of an image of the blood vessel is provided and the Dijkstra algorithm is used to find the shortest path along the current established from a steady-state circuit model with the current source and sink given by user-placed seeds on the image. Since the method looks at the change in current flow, multiply-connected objects that are either significantly larger or smaller than the vessel will be ignored since the current flow will change dramatically. In contrast, a simple, shortest-path, approach between the source and terminus of the vessel would be unlikely to stay within the vessel if it were to touch another object with similar intensity.