Ultrasound-based characterization of particles in a fluid-filled hollow structure

An ultrasound system for characterization of a mobility of particles in a fluid-filled blood vessel, the ultrasound system comprising:

• an ultrasound probe configured to emit an ultrasound signal with a frequency spectrum that has a local maximum at a variable measurement frequency, in a direction of a part area of the fluid-filled blood vessel and to detect reflected components of the ultrasound signal as a result of an ultrasound reflection of the ultrasound signal;
• a control unit configured to actuate the ultrasound probe, which is configured to tune the variable measurement frequency in a predetermined measurement interval;
• and
• an evaluation unit configured to acquire a spectral response curve of the ultrasound reflection as a function of the variable measurement frequency based on the reflected components, and determine a restriction of movement of the particles in a fluid of the fluid-filled blood vessel via:
• (1) an adhesion of the particles to an inner wall of the fluid-filled blood vessel, or (2) an adhesion of the particles to a medical instrument in the fluid-filled blood vessel, wherein the restriction of movement is deduced via at least one curve property of the spectral response curve of the ultrasound reflection,
• wherein the restriction of movement of the particles reflects a mobility of the particles located in the part area of the fluid-filled blood vessel, and
• wherein the particles are embolization beads having diameters in a range of 10 micrometers to 500 micrometers.

A non-transitory computer program product with commands that, when executed by an ultrasound system, cause the ultrasound system to:

• emit, by an ultrasound probe of the ultrasound system, an ultrasound signal with a frequency spectrum, which has a local maximum at a variable measurement frequency, in a direction of a part area of a fluid-filled blood vessel;
• detect, by the ultrasound probe, reflected components of the ultrasound signal as a result of an ultrasound reflection of the ultrasound signal;
• actuate the ultrasound probe by a control unit of the ultrasound system;
• tune, by the control unit, the variable measurement frequency in a predetermined measurement interval;
• acquire, by an evaluation unit of the ultrasound system, a spectral response curve of the ultrasound reflection as a function of the variable measurement frequency based on the reflected components;
• and
• determine, by the evaluation unit, a restriction of movement of particles in a fluid of the fluid-filled blood vessel via:
• (1) an adhesion of the particles to an inner wall of the fluid-filled blood vessel, or (2) an adhesion of the particles to a medical instrument in the fluid-filled blood vessel, wherein the restriction of movement is deduced via at least one curve property of the spectral response curve of the ultrasound reflection,
• wherein the restriction of movement of the particles reflects a mobility of the particles located in the part area of the fluid-filled blood vessel, and
• wherein the particles are embolization beads having diameters in a range of 10 micrometers to 500 micrometers.