Abstract: A system utilizing thermoacoustic imaging to estimate tissue temperature within a region of interest that includes an object of interest and a reference which are separated by at least one boundary located at least at two boundary locations. The system uses a thermoacoustic imaging system that includes an adjustable radio frequency (RF) applicator configured to emit RF energy pulses into the tissue region of interest and heat tissue therein and an acoustic receiver configured to receive multi-polar acoustic signals generated in response to heating of tissue in the region of interest; and one or more processors that are able to: process received multi-polar acoustic generated in the region of interest in response to the RF energy pulses to determine a peak-to-peak amplitude thereof; and calculate a temperature at the at least two boundary locations using the peak-to-peak amplitudes of the multi-polar acoustic signals and a distance between the boundary locations.

Abstract: A method and system for enhancing radio frequency energy delivery to a tissue region of interest. The method and system direct with a radio frequency (RF) applicator, one or more RF energy pulses into the tissue region of interest, the tissue region of interest comprising an object of interest and at least one reference that are separated by at least one boundary; detect with an acoustic receiver, at least one bipolar acoustic signal generated in the tissue region of interest in response to the RF energy pulses and processing the at least one bipolar acoustic signal to determine a peak-to-peak amplitude thereof; adjust the RF applicator to maximize the peak-to-peak amplitude of bipolar acoustic signals generated in the tissue region of interest in response to RF energy pulses generated by the adjusted RF applicator; and direct with the adjusted RF applicator, one or more RF energy pulses into the region of interest.

Abstract: A thermoacoustic imaging system and method for monitoring tissue temperature within a region of interest, which has an object of interest and a reference that are separated by at least one boundary. The system and method include a thermoacoustic imaging system with an adjustable radio frequency (RF) applicator configured to emit RF energy pulses into the tissue region of interest and heat tissue therein, an acoustic receiver configured to receive bipolar acoustic signals generated in response to heating of tissue in the region of interest, and one or more processors that process at least one received bipolar acoustic signal generated in the region of interest in response to the RF energy pulses to determine a peak-to-peak amplitude thereof and calculate a temperature at the at least one boundary using the peak-to-peak amplitude of the at least one bipolar acoustic signal.

Abstract: Combined transducer arrays for imaging features of tissue include a transducer array configured for transmit-receive ultrasound imaging, and a transducer array configured for receive-only thermoacoustic imaging. The transmit-receive transducer array includes a plurality of transmit-receive array elements, and the receive-only transducer array includes a plurality of receive-only array elements. The receive-only array elements are registered with and surround the transmit-receive array elements. The receive-only transducer array and transmit-receive transducer array may be housed in an ultrasound probe. The combined transducer arrays may be used in composite imaging of tissue, based on the registration of the transmit-receive array elements and the receive-only array elements.

Abstract: A method for providing an image of a subject by utilizing an array of transmission elements in a thermoacoustic imaging apparatus.

Abstract: A system utilizing thermoacoustic imaging to estimate tissue temperature within a region of interest that includes an object of interest and a reference which are separated by at least one boundary located at least at two boundary locations. The system uses a thermoacoustic imaging system that includes an adjustable radio frequency (RF) applicator configured to emit RF energy pulses into the tissue region of interest and heat tissue therein and an acoustic receiver configured to receive multi-polar acoustic signals generated in response to heating of tissue in the region of interest; and one or more processors that are able to: process received multi-polar acoustic generated in the region of interest in response to the RF energy pulses to determine a peak-to-peak amplitude thereof; and calculate a temperature at the at least two boundary locations using the peak-to-peak amplitudes of the multi-polar acoustic signals and a distance between the boundary locations.

Abstract: A thermoacoustic imaging system and method for monitoring tissue temperature within a region of interest, which has an object of interest and a reference that are separated by at least one boundary. The system and method include a thermoacoustic imaging system with an adjustable radio frequency (RF) applicator configured to emit RF energy pulses into the tissue region of interest and heat tissue therein, an acoustic receiver configured to receive bipolar acoustic signals generated in response to heating of tissue in the region of interest, and one or more processors that process at least one received bipolar acoustic signal generated in the region of interest in response to the RF energy pulses to determine a peak-to-peak amplitude thereof and calculate a temperature at the at least one boundary using the peak-to-peak amplitude of the at least one bipolar acoustic signal.

Abstract: A method and system for enhancing radio frequency energy delivery to a tissue region of interest. The method and system direct with a radio frequency (RF) applicator, one or more RF energy pulses into the tissue region of interest, the tissue region of interest comprising an object of interest and at least one reference that are separated by at least one boundary; detect with an acoustic receiver, at least one bipolar acoustic signal generated in the tissue region of interest in response to the RF energy pulses and processing the at least one bipolar acoustic signal to determine a peak-to-peak amplitude thereof; adjust the RF applicator to maximize the peak-to-peak amplitude of bipolar acoustic signals generated in the tissue region of interest in response to RF energy pulses generated by the adjusted RF applicator; and direct with the adjusted RF applicator, one or more RF energy pulses into the region of interest.

Abstract: A system and method utilizing thermoacoustic imaging to estimating tissue temperature within a region of interest that includes an object of interest and a reference which are separated by at least one boundary located at least at two boundary locations. The system and method use a thermoacoustic imaging system that includes an adjustable radio frequency (RF) applicator configured to emit RF energy pulses into the tissue region of interest and heat tissue therein and an acoustic receiver configured to receive bipolar acoustic signals generated in response to heating of tissue in the region of interest; and one or more processors that are able to: process received bipolar acoustic generated in the region of interest in response to the RF energy pulses to determine a peak-to-peak amplitude thereof; and calculate a temperature at the at least two boundary locations using the peak-to-peak amplitudes of the bipolar acoustic signals and a distance between the boundary locations.

Abstract: A thermoacoustic imaging method comprises administering a thermoacoustic imaging contrast agent to a subject, the thermoacoustic imaging contrast agent having a viscosity higher than blood and substantially similar to a viscosity of a known computed tomography (CT) or magnetic resonance imaging (MRI) contrast agent; and imaging the subject with a thermoacoustic imaging system. The thermoacoustic imaging contrast agent may comprise an ionic solution and thickening agent mixture, with an optional heating agent. The ionic salt makes 0.5% to 5.0% of the ionic solution by weight and the remainder of the ionic solution is water. The thickening agent makes 3% to 50% of the mixture by weight.

Abstract: Combined transducer arrays for imaging features of tissue include a transducer array configured for transmit-receive ultrasound imaging, and a transducer array configured for receive-only thermoacoustic imaging. The transmit-receive transducer array includes a plurality of transmit-receive array elements, and the receive-only transducer array includes a plurality of receive-only array elements. The receive-only array elements are registered with and surround the transmit-receive array elements. The receive-only transducer array and transmit-receive transducer array may be housed in an ultrasound probe. The combined transducer arrays may be used in composite imaging of tissue, based on the registration of the transmit-receive array elements and the receive-only array elements.

Abstract: A thermoacoustic imaging system is provided for use in combination with an ultrasound imaging system for imaging features of tissue, the ultrasound imaging system including an ultrasound imaging probe including a transmit-receive transducer array with a plurality of transmit-receive array elements. The thermoacoustic imaging system includes a receive-only transducer array with a plurality of receive-only array elements, registered with the plurality of transmit-receive array elements. The transmit-receive transducer array is housed in an ultrasound imaging probe, and the receive-only transducer array is housed in a thermoacoustic imaging probe. The thermoacoustic imaging probe is mechanically joined to the ultrasound imaging probe, e.g., as a sleeve fitted to the ultrasound imaging probe.

Abstract: A method and system for estimating a specific absorption rate of a tissue region prior to performing a magnetic resonance (MR) imaging scan on the tissue region. The method comprises radiating the tissue region with a plurality of short pulses, wherein the tissue region emits thermoacoustic signals responsive to the short pulses, receiving the thermoacoustic signals by at least one ultrasonic transducer, calculating a temperature rise of the tissue region based on the received thermoacoustic signals, scaling the temperature rise to estimate a temperature rise of the tissue region resulting from an MR imaging scan, and estimating the specific absorption rate of the tissue region based on the estimated temperature rise.

Abstract: A thermoacoustic imaging system is provided for use in combination with an ultrasound imaging system for imaging features of tissue, the ultrasound imaging system including an ultrasound imaging probe including a transmit-receive transducer array with a plurality of transmit-receive array elements. The thermoacoustic imaging system includes a receive-only transducer array with a plurality of receive-only array elements, registered with the plurality of transmit-receive array elements. The transmit-receive transducer array is housed in an ultrasound imaging probe, and the receive-only transducer array is housed in a thermoacoustic imaging probe. The thermoacoustic imaging probe is mechanically joined to the ultrasound imaging probe, e.g., as a sleeve fitted to the ultrasound imaging probe.

Abstract: A method and system for estimating a specific; absorption rate of a tissue region prior to performing a magnetic resonance (MR) imaging scan on the tissue region. The method comprises radiating the tissue region with a plurality of short pulses, wherein the tissue region emits thermoacoustic signals responsive to the short pulses, receiving the thermoacoustic signals by at least one ultrasonic transducer, calculating a temperature rise of the tissue region based on the received thermoacoustic signals, scaling the temperature rise to estimate a temperature rise of the tissue region resulting from an MR imaging scan, and estimating the specific absorption rate of the tissue region based on the estimated temperature rise.

Abstract: Methods and systems to analyze soft tissue or vasculature in a subject, form images with enhanced soft tissue contrast, determine blood flow parameters in soft tissue or vasculature, and to aid in the diagnosis of disease using thermoacoustic methods. Pulsed electromagnetic energy is administered to tissue to excite a thermoacoustic signal in the soft tissue or vasculature. An acoustic receiver or receiver array is coupled to a subject to detect and record the thermoacoustic signals produced. Thermoacoustic data are acquired after administration of a physiologically-tolerable tracer or contrast agent. The acquired data may be analyzed to produce images of the soft tissue and vasculature (angiogram), to determine blood flow parameters, and/or to diagnose disease in a subject.

Abstract: A volume flow meter for displaying two-dimensional volume flow through a vessel, comprising an ultrasound instrument with scan head, a location and orientation sensor mounted to the scan head, and a computer connected to the ultrasound instrument and the sensor. The scan head is adapted to be positioned adjacent the vessel under investigation, for generating a raster of pixels which defines a color image representing flow velocities in the vessel through an image plane of the scan head. The sensor measures position and orientation of the scan head in three dimensions and generates a signal representative thereof to the computer. The computer receives said raster of pixels and the signal from the sensor and in response calculates the position and orientation of the vessel axis in three-dimensions responsive to orientation of the image plane longitudinally of the vessel. The computer then determines an angle .theta.