Patent ID: 11872083
Assignee: NATIONAL CHENG KUNG UNIVERSITY
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 2:
3. A method for measuring elasticity of a biological tissue, comprising:
a first scanning step of using the ultrasonic device of claim 1 to perform, when the installation base is positioned in one of the at least two testing positions, image scanning on the biological tissue when the vibrator does not vibrate to obtain a reference ultrasound image, wherein the ultrasonic signal induces an ultrasonic shear wave that travels in the biological issue;
a second scanning step of using the ultrasonic probe to perform, when the installation base is positioned in said one of the at least two testing positions and the vibrator is vibrating to apply a mechanical wave to the biological tissue, image scanning on the biological tissue with a predetermined scanning frequency, so as to obtain a plurality of testing ultrasound images;
a displacement analysis step of calculating, for each of the testing ultrasound images, a timewise displacement of the ultrasonic shear wave relative to the reference ultrasound image at a time point the testing ultrasound image was taken, so as to convert the testing ultrasound image into a respective displacement image;
a spatial-frequency-domain (SFD) transforming step of transforming the displacement images that correspond to the testing ultrasound images into a spatial frequency domain, so as to obtain a plurality of SFD displacement images that respectively correspond to the displacement images;
a first filtering step of performing, for each of the SFD displacement images, filtering on the SFD displacement image with respect to a longitudinal direction in which the ultrasonic signal travels to obtain a longitudinal SFD displacement image, the longitudinal direction being parallel to the Z-axis;
a second filtering step of performing, for each of the SFD displacement images, filtering on the SFD displacement image with respect to lateral directions that are perpendicular to the longitudinal direction to obtain a set of lateral SFD displacement images that respectively correspond to the lateral directions;
a first time-domain transforming step of transforming the longitudinal SFD displacement images that are obtained respectively from the SFD displacement images into a time domain, so as to obtain a plurality of longitudinal time-domain displacement images;
a second time-domain transforming step of transforming the sets of the lateral SFD displacement images that are obtained respectively from the SFD displacement images into the time domain, so as to obtain a plurality of sets of lateral time-domain displacement images, wherein the lateral time-domain displacement images in each of the sets respectively correspond to the lateral directions; and
an elasticity analysis step of calculating longitudinal elasticity of the biological tissue based on a timewise variation of phases of the longitudinal time-domain displacement images, and calculating lateral elasticities of the biological tissue based on timewise variations of phases of the lateral time-domain displacement images;
wherein the longitudinal elasticity and the lateral elasticities of the biological tissue are usable for making medical determinations related to muscles or tendons.