Processing velocity information in an ultrasonic system

An apparatus for making vascular measurements within a living subject in an ultrasonic system comprising:

• a. a first circuit for determining peak velocities of a spectra of echoes over a period of time due to pulses emitted into a subject under examination and storing said peak velocities into an array of peak velocities, said first circuit is further configured to divide said spectra into a plurality of regions to determine a threshold magnitude of said peak velocities and identify a first velocity that exceeds said threshold magnitude;
• b. a second circuit coupled to said first circuit for determining an optimum cardiac cycle for said subject under examination based upon said time series of said peak velocities;
• and
• c. a third circuit coupled to said second circuit for performing vascular measurements of said optimum cardiac cycle.

A method in an ultrasonic system of determining an optimum cardiac cycle comprising the following steps:

• a. determining a time series of velocities over a period of time due to pulses emitted into a subject under examination;
• b. identifying discontinuities in said time series of peak velocities which exceeds a threshold;
• c. determining a candidate peak velocity between said each of said discontinuities to form a set of peak systoles;
• d. determining a peak systole in said set of peak systoles which is followed by a second peak systole and which is preceded by a minimum peak velocity which occurs within a predetermined time before said peak systole and identifying said minimum peak velocity as an end diastole (ED);
• e. locating a second minimum velocity which occurs before said second peak systole and identifying said second minimum velocity as a second end diastole (ED);
• and
• f. identifying a time period between said end diastole and said second end diastole as said optimum cardiac cycle.

An apparatus for determining an optimum cardiac cycle comprising:

• a. an input means for determining a time series of velocities over a period of time due to pulses emitted into a subject under examination;
• b. an identification means coupled to said input means for identifying discontinuities in said time series of peak velocities which exceeds a threshold;
• c. a peak detection means coupled to said identification means for determining a peak velocity between said each of said discontinuities to form a set of peak systoles;
• d. a determination means coupled to said peak detection means for determining a peak systole in said set of peak systoles which is followed by a second peak systole and which is preceded by a minimum peak velocity which occurs within a predetermined time before said peak systole and identifying said minimum peak velocity as an end diastole (ED);
• e. a second minimum velocity detection means coupled to said determination means for locating a second minimum velocity which occurs before said second peak systole and identifying said second minimum velocity as a second end diastole (ED);
• and
• f. an optimum cardiac cycle identifying means coupled to said minimum velocity detection means for identifying a time period between said end diastole and said second end diastole as said optimum cardiac cycle.