Ultrasonic method and apparatus for tissue characterization and imaging of nonlinear parameter

Claim 1

An ultrasonic method for characterization by nonlinear parameter data of a structure of an object to be examined which comprises the steps of: transmitting ultrasonic pulses along a line extending into the object at a plurality of different output power levels; receiving a plurality of echoes of said ultrasonic pulses reflected from discontinuities in the structure at discrete points along the line; and analyzing amplitudes of said received echoes at each of said different output power levels to obtain data relating to the nonlinear parameter B/A of the structure.

Claim 5

An apparatus for characterization and imaging by nonlinear parameter data of a structure of an object to be examined comprising: an array of ultrasonic transducer elements arranged in a first dimension, each transducer element to transmit when activated ultrasonic pulses along a line extending into the object in a second dimension and to receive echoes of said ultrasonic pulses from discrete points along said line; means for activating said ultrasonic transducer elements at a plurality of different power levels; means for analyzing amplitudes of said echoes for each of said transducer elements arranged in said first dimension at each of said different power levels to obtain nonlinear parameter data B/A along each of said lines in said second dimension; means for scanning said data obtained in said first and second dimensions; and means responsive to said scanning means for displaying said nonlinear parameter data in two dimensions.

Claim 6

An apparatus for characterization and imaging by nonlinear parameter data of a structure of an object to be examined comprising: an array of ultrasonic transducer elements arranged in a first dimension, each transducer element to transmit when activated ultrasonic pulses along a line extending into the object in a second dimension and to receive echoes of said ultrasonic pulses from discrete points along said line; means for activating said ultrasonic transducer elements at a plurality of different power levels; means for analyzing amplitudes of said echoes for each of said transducer elements arranged in said first dimension at each of said different power levels to obtain nonlinear parameter data B/A along each of said lines in said second dimension; means for scanning said data obtained in said first and second dimensions; and means responsive to said scanning means for displaying said nonlinear parameter data in two dimensions.

Claim 8

An apparatus for characterization and imaging by nonlinear parameter data of a structure of an object to be examined comprising: an array of ultrasonic transducer elements arranged in a first dimension, each transducer element to transmit when activated ultrasonic pulses along a line extending into the object in a second dimension and to receive echoes of said ultrasonic pulses from discrete points along said line; means for activating said ultrasonic transducer elements at a plurality of different power levels; means for analyzing amplitudes of said echoes for each of said transducer elements arranged in said first dimension at each of said different power levels to obtain nonlinear parameter data B/A along each of said lines in said second dimension; and means responsive to said analyzing means for displaying said nonlinear parameter data in two dimensions; wherein said activating means includes means for varying voltages u activating said transducer elements; wherein said transducer elements include means for converting said received echoes into voltages v; and wherein said means for analyzing comprises means for calculating linear parameter data k and nonlinear parameter data a for each of said discrete points according to the equation: ##EQU4##

Claim 9

An apparatus for characterization and imaging by nonlinear parameter data of a structure of an object to be examined comprising: an array of ultrasonic transducer elements arranged in a first dimension, each transducer element to transmit when activated ultrasonic pulses along a line extending into the object in a second dimension and to receive echoes of said ultrasonic pulses from discrete points along said line; means for activating said ultrasonic transducer elements at a plurality of different power levels; means for analyzing amplitudes of said echoes for each of said transducer elements arranged in said first dimension at each of said different power levels to obtain nonlinear parameter data B/A along each of said lines in said second dimension; and means responsive to said analyzing means for displaying said nonlinear parameter data in two dimensions; wherein said activating means includes means for varying voltages u activating said transducer elements; wherein said transducer elements include means for converting said received echoes into voltages v; and wherein said means for analyzing comprises means for calculating linear parameter data k and nonlinear parameter data a for each of said discrete points according to the equation: ##EQU4##

Claim 12

An apparatus for characterization and imaging by nonlinear parameter date of a structure of an object to be examined, comprising: (a) an array of ultrasonic transducers arranged in a first dimension, each transducer transmitting, when activated, ultrasonic pulses in a predetermined line extending into said object in a second dimension, each transducer receiving echoes of the pulses being reflected from discontinuities in the structure along the predetermined line; (b) a driving circuit for activating each of said transducers at a plurality of different power levels; (c) means for sampling echoes received by each transducer at a frequency corresponding to the time calculated for sound to theoretically travel from each transducer to a discrete set of points along said line and back again through said object; (d) an arithmetic logic unit for calculating a linear parameter B/A representative of the pressure dependence of sound velocity for each of said discrete points using amplitudes of echoes sampled at each of said different power levels; and (e) means responsive to said logic unit means for displaying, in two dimensions, parameters calculated for each discrete point of each line.

Claim 13

An apparatus for characterization and imaging by nonlinear parameter date of a structure of an object to be examined, comprising: (a) an array of ultrasonic transducers arranged in a first dimension, each transducer transmitting, when activated, ultrasonic pulses in a predetermined line extending into said object in a second dimension, each transducer receiving echoes of the pulses being reflected from discontinuities in the structure along the predetermined line; (b) a driving circuit for activating each of said transducers at a plurality of different power levels; (c) means for sampling echoes received by each transducer at a frequency corresponding to the time calculated for sound to theoretically travel from each transducer to a discrete set of points along said line and back again through said object; (d) an arithmetic logic unit for calculating a linear parameter B/A representative of the pressure dependence of sound velocity for each of said discrete points using amplitudes of echoes sampled at each of said different power levels; and (e) means responsive to said logic unit means for displaying, in two dimensions, parameters calculated for each discrete point of each line.