Ultrasound diagnosis apparatus
View Patent ↗When multiple tissues having differing speeds of sound are intermixed in the viewing field of a measured subject such as a living body, the invention measures hardness, such as modulus of elasticity or viscosity, with high precision.
1. An ultrasound diagnosis apparatus, comprising:
an ultrasound probe that receives and transmits an echo signal from an inside of a subject;
a displacement generating unit that radiates an ultrasonic focused beam to the inside of the subject so as to displace a tissue; and
a displacement detecting unit that receives the echo signal and detects a temporal waveform of a displacement of a shear wave generated by the ultrasonic focused beam in a plurality of positions,
wherein the displacement detecting unit is provided with a heterogeneity detecting device that evaluates a heterogeneity of the subject based upon the temporal waveform, and
wherein the heterogeneity detecting device acquires at least two types of information from the temporal waveform, calculates a width of the temporal waveform based upon the at least two types of information, and evaluates the heterogeneity.
2. The ultrasound diagnosis apparatus of claim 1 ,
wherein the heterogeneity is a heterogeneity of a sonic velocity of the shear wave that proceeds from a structure of the subject.
3. The ultrasound diagnosis apparatus of claim 1 , wherein the heterogeneity is a heterogeneity of a sonic velocity of the shear wave that proceeds from a frequency dispersion.
4. The ultrasound diagnosis apparatus of claim 1 , wherein the at least two types of informations are an integrated value and a maximum amplitude value respectively of the temporal waveform.
5. The ultrasound diagnosis apparatus of claim 1 , wherein the at least two types of informations are a half-width and a maximum amplitude value respectively of the temporal waveform.
6. The ultrasound diagnosis apparatus of claim 1 , wherein the heterogeneity detecting device calculates a number of peaks of the shear wave and evaluates the heterogeneity.
7. The ultrasound diagnosis apparatus of claim 1 , wherein the heterogeneity detecting device performs space differential operation for the displacement of the shear wave.
8. The ultrasound diagnosis apparatus of claim 1 , wherein the displacement generating unit is provided with a focal position setting device that sets a focal point of the ultrasonic focused beam.
9. The ultrasound diagnosis apparatus of claim 8 , wherein: the focal position setting device sets a focal point of the ultrasonic focused beam in different positions in the subject.