In vivo measurements of muscle elasticity applying shear waves excited with focused ultrasound

The common algorithm of shear waves excitation for diagnostical ultrasonic devices was modified for measurements in muscles. We measured the speed of shear waves, excited by a focused ultrasound at a frequency of 5 MHz in the muscles of the volunteers. Siemens Acuson S2000 was used for in vivo measurements. The suggested algorithm was tested on the muscle mimicking phantoms. The values of shear wave velocities in the same areas of studied phantoms at the same angles measured with Siemens Acuson S2000 system corresponded to the values obtained by Verasonics, where the region of shear wave excitation had a form of “blade” of thickness less than 0.5 mm, length and width of 1.5-2 mm. Due to this form of the region, the excited shear wave has propagated codirectional with the long side of the ultrasonic medical probe. Thus, the direction of propagation of the shear wave with respect to the phantom fibers, became dependent on the position of the probe. [The reported study was funded by RFBR and Moscow city Government according to the research project № 15-32-70016 «mol_а_mos», by RFBR according to the research project № 16-02-00719 а, and by Program for Sponsorship of Leading Scientific Schools (Grant NSh-7062.2016.2).]