Abstract: A method and apparatus for displaying an image representing the flow of a substance in a scanned area. An Angio scanner scans a region of tissue and generates Ultrasound Angio data representing the flow of blood in the region of tissue. Relatively small blood flows are difficult to detect in images based solely on Angio data. To enhance the visibility of small blood flows, spatial derivative values are calculated from the Angio data. A fraction of the original Angio data plus a bias is summed with the spatial derivative values to generate composite values. An image of the scanned region is displayed with colors or grayscale shades based on the composite values. The resulting image depicts blood vessels in an edge-enhanced format, giving a three-dimensional appearance.