Systems and methods for increasing efficiency of ultrasound waveform tomography
Ultrasound tomography imaging methods for imaging a tissue medium with one or more ultrasound transducer arrays comprising a plurality of transducers, wherein said transducers comprise source transducers, receiving transducers. The methods include assigning a phase value or time delay to source transducers, exciting the transducers and calculating a search direction based on data relating to the excited transducers.
1. An ultrasound tomography imaging method for imaging a tissue medium with one or more ultrasound transducer arrays comprising a plurality of transducers, the method comprising:
assigning a plurality of different phase values to a plurality of at least three different source transducers of the plurality of transducers;
exciting the at least three source transducers in accordance with the assigned different phase values to generate a plurality of ultrasound waveforms within the tissue medium;
receiving data from a plurality of receiving transducers of the plurality of transducers in accordance with transmissions and reflections of the plurality of ultrasound waveforms within the tissue medium; and
calculating a search direction based on data from the receiving transducers,
wherein the method further comprises performing a numerical simulation of forward propagation of wavefields from the source transducers and backward propagation of wavefields from the receiving transducers,
wherein the calculating the search direction is based on the forward propagation of wavefields and the backward propagation of wavefields, and
wherein the method further comprises:
updating a model based on the search direction;
computing an ultrasound waveform tomography image reconstruction in accordance with the updated model; and
performing numerical waveform inversion to generate the ultrasound waveform tomography image reconstruction,
wherein the plurality of different phase values are assigned during the numerical waveform inversion.
2. The ultrasound tomography imaging method of claim 1 , further comprising:
receiving a transmission signal and a reflection signal at one of the receiving transducers within the one or more ultrasound transducer arrays; and
generating an ultrasound waveform tomography image reconstruction using the data received in accordance with the transmission signal and the reflection signal.
3. An ultrasound tomography imaging method for imaging a tissue medium with one or more ultrasound transducer arrays comprising a plurality of transducers, the method comprising:
assigning a plurality of different phase values to a plurality of at least three different source transducers of the plurality of transducers;
exciting the at least three source transducers in accordance with the assigned different phase values to generate a plurality of ultrasound waveforms within the tissue medium;
receiving data from a plurality of receiving transducers of the plurality of transducers in accordance with transmissions and reflections of the plurality of ultrasound waveforms within the tissue medium; and
calculating a search direction based on data from the receiving transducers,
wherein the method further comprises performing a numerical simulation of forward propagation of wavefields from the source transducers and backward propagation of wavefields from the receiving transducers,
wherein the calculating the search direction is based on the forward propagation of wavefields and the backward propagation of wavefields,
wherein the method further comprises:
updating a model based on the search direction; and
computing an ultrasound waveform tomography image reconstruction in accordance with the updated model, and
wherein the ultrasound wave tomography image reconstruction is a function of:
E
(
m
)
=
min
m
∑
s
=
1
N
s
∫
[
d
s
(
t
)
-
p
S
(
m
,
t
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]
2
d
t
,
where E(m) is a misfit function, d is one of transmission data and reflection data, p is a simulated waveform from the numerical simulation, s is a source index indicating one of the source transducers, N s is the number of source transducers, and m is a model parameter of the model.
4. An ultrasound tomography imaging system for imaging a tissue medium comprising:
two or more ultrasound transducer arrays spaced apart from each other, each of the ultrasound transducer arrays comprising a plurality of transducers;
a processor; and
memory storing instructions that, when executed by the processor, cause the processor to:
assign a plurality of different phase values to a plurality of at least three different source transducers of the plurality of transducers;
exciting the at least three source transducers in accordance with the assigned different phase values to generate a plurality of ultrasound waveforms within the tissue medium;
receiving data from a plurality of receiving transducers of the plurality of transducers in accordance with transmissions and reflections of the plurality of ultrasound waveforms within the tissue medium; and
calculating a search direction based on data from the receiving transducers,
wherein the memory further stores instructions that, when executed by the processor, cause the processor to perform a numerical simulation of forward propagation of wavefields from the source transducers and backward propagation of wavefields from the receiving transducers,
wherein the search direction is calculated based on the forward propagation of wavefields and the backward propagation of wavefields,
wherein the memory further stores instructions that, when executed by the processor, cause the processor to:
update a model based on the search direction; and
compute an ultrasound waveform tomography image reconstruction in accordance with the updated model,
wherein the memory further stores instructions that, when executed by the processor, cause the processor to perform numerical waveform inversion to generate the ultrasound waveform tomography image reconstruction, and
wherein the plurality of different phase values are assigned during the numerical waveform inversion.
5. The ultrasound tomography imaging system of claim 4 , wherein the memory further stores instructions that, when executed by the processor, cause the processor to:
receive a transmission signal and a reflection signal at one of the receiving transducers within the one or more ultrasound transducer arrays; and
generate an ultrasound waveform tomography image reconstruction using the data received in accordance with the transmission signal and the reflection signal.
6. An ultrasound tomography imaging system for imaging a tissue medium comprising:
two or more ultrasound transducer arrays spaced apart from each other, each of the ultrasound transducer arrays comprising a plurality of transducers;
a processor; and
memory storing instructions that, when executed by the processor, cause the processor to:
assign a plurality of different phase values to a plurality of at least three different source transducers of the plurality of transducers;
exciting the at least three source transducers in accordance with the assigned different phase values to generate a plurality of ultrasound waveforms within the tissue medium;
receiving data from a plurality of receiving transducers of the plurality of transducers in accordance with transmissions and reflections of the plurality of ultrasound waveforms within the tissue medium; and
calculating a search direction based on data from the receiving transducers,
wherein the memory further stores instructions that, when executed by the processor, cause the processor to perform a numerical simulation of forward propagation of wavefields from the source transducers and backward propagation of wavefields from the receiving transducers,
wherein the search direction is calculated based on the forward propagation of wavefields and the backward propagation of wavefields,
wherein the memory further stores instructions that, when executed by the processor, cause the processor to:
update a model based on the search direction; and
compute an ultrasound waveform tomography image reconstruction in accordance with the updated model, and
wherein the ultrasound wave tomography image reconstruction is a function of:
E
(
m
)
=
min
m
∑
s
=
1
N
s
∫
[
d
s
(
t
)
-
p
S
(
m
,
t
)
]
2
d
t
,
where E(m) is a misfit function, d is one of transmission data and reflection data, p is a simulated waveform from the numerical simulation, s is a source index indicating one of the source transducers, N s is the number of source transducers, and m is a model parameter of the model.