An embodiment in accordance with the present invention provides a precise catheter tracking system, Active Ultrasound Pattern Injection System (AUSPIS). AUSPIS establishes ultrasonic communication between any ultrasound external probe and internal catheter (CUTE catheter). The system receives image beacon pulses, analyzes the acquired signal, and fires one or a series of active echo pulses from the same active echo element with a proper timing, frequency, duration and amplitude. Thus it enables injection of any “virtual” pattern into the B-mode image. The pattern injected to the B-mode image is from actively encoded ultrasound field in the tissue. The encoding is based on B-mode ultrasound image formation technique, so it doesnt require hardware or software modification to the US machine. It continuously measures the local acoustic signal amplitude, by which sub-millimeter elevation localization accuracy can be achieved. The technique can be used for tracking, tool guidance, and annotation with configured tracking formations.
