1. A method for detecting a stenosis, comprising the steps of: generating ultrasound data reflected from an internal site using an ultrasound machine including an ultrasound transducer and an ultrasound back-end subsystem; extracting tissue vibration data from the ultrasound data using a tissue vibration processor, where the tissue vibration processor decreases components of the ultrasound data induced by transducer movement, respiration and cardiac pulsation in the tissue vibration data, such that the tissue vibration data corresponds to vibrations caused by blood flow turbulence, the blood flow turbulence being indicative of the stenosis; carrying out the following with the ultrasound back-end subsystem programmed with non-transitory computer readable media instructions: from the tissue motion signal, the vibration image indicating a spatial position of the tissue motion relative to the internal site; generating a B-mode image from the ultrasound data showing underlying anatomy of the internal site; overlaying the generated vibration image with the generated B-mode image so as to provide stenosis position information with reference to the underlying anatomy of the internal site; and outputting the overlaid images.