Abstract: A method for imaging an organ or internal structure within a body to obtain three-dimensional reconstruction of the organ or internal structure. The method includes steps of providing an intraluminal ultrasound imaging system capable of obtaining echographic images of the surrounding of a catheter imaging tip located inside the body of a patient, and a catheter tracking system comprising at least one ultrasound transducer mounted adjacent the imaging tip of an intraluminal ultrasound catheter for insertion into a patient, a plurality of transducers located away from said intraluminal ultrasound catheter so as to form a reference frame, and circuitry for calculating positions of the plurality of frame transducers relative to each other and positions of said catheter tip transducers relative to said plurality of frame transducers.