Abstract: Computer-implemented methods for use in improving the diagnostic quality of images, including intravascular ultrasound (IVUS) images, are disclosed. The methods include using a non-linear, probabilistic classifier algorithm to analyze a plurality of spatiotemporal features of RF backscatter and to produce a blood likelihood map or blood probability map that corresponds to the original IVUS image. The methods disclosed herein allow for visualizing both static and dynamic characteristic of a vessel either by producing a transparency modulated color overlay of the blood likelihood map without altering the underlying IVUS image or by processing the IVUS image based upon the blood likelihood map to better distinguish between static and dynamic components of the vessel.