A method of registering the position of an object moving in a target volume in an ultrasound imaging system includes capturing a first ultrasound image of a target volume. A second ultrasound image of the target volume is then captured after the capturing of the first ultrasound image. The position of the object in the target volume is identified using differences detected between the first and second ultrasound images. In another aspect, a region of interest in the target volume is determined. A segment of an operational scan range of a transducer of the ultrasound imaging system encompassing the region of interest is determined. The transducer is focused on the segment of the operational scan range during image capture.
