Patent ID: 9326748
Filing Date: 2016-05-03
CPC Classification: A61B,G01S

Claim Text:
1. A clinical apparatus comprising: at least one sensor which is configured to sense one selected from a group consisting of an ultrasound signal, a magnetic nuclear resonance signal, an electromagnetic wave, and light; a storage which is configured to store at least one of strain tensor component data, strain rate tensor component data, and acceleration vector component data measured in a ROI (region of interest) set in a target by using said at least one sensor; and a data processor which is configured to calculate at least one of a stress and a pressure of at least one arbitrary point within the ROI by utilizing first reference data representing at least one reference value about at least one of the stress and the pressure and at least one reference position that has said at least one reference value, the pressure being a mean of normal stress tensor components, and each of the stress and the pressure being expressed using at least one product of at least one elastic constant and a volume strain, at least one product of at least one visco elastic constant and a volume strain rate, or at least one product of at least one viscosity and a volume strain rate; wherein said data processor is configured to linearly and directly calculate said at least one of the stress and the pressure while setting to unknown a Poisson's ratio or at least one of said at least one elastic constant, said at least one visco elastic constant, and said at least one viscosity, which expresses said at least one of the stress and the pressure, based on at least said first reference data and at least one equation representing a relation between (i) said at least one of the stress and the pressure, (ii) at least one of other stresses that is at least one stress tensor component expressed using at least one product of said at least one elastic constant or other elastic constants and the measured strain tensor component data, at least one product of said at least one visco elastic constant or other visco elastic constants and the measured strain rate tensor component data, or at least one product of said at least one viscosity or other viscosities and the measured strain rate tensor component data, (iii) when the arbitrary point within the ROI has a non-zero acceleration vector, at least one inertia vector component expressed using a product of a density and the measured acceleration vector component data, and (iv) when the arbitrary point within the ROI has a mechanical source, the mechanical source.