Abstract: A medical imaging and therapy device is provided that may include any of a number of features. One feature of the device is that it can image a target tissue volume and apply ultrasound energy to the target tissue volume. In some embodiments, the medical imaging and therapy device is configured controllably apply ultrasound energy into the prostate by maintaining a cavitational bubble cloud generated by an ultrasound therapy system within an image of the prostate generated by an imaging system. The medical imaging and therapy device can be used in therapeutic applications such as Histotripsy, Lithotripsy, and HIFU, for example. Methods associated with use of the medical imaging and therapy device are also covered.

Abstract: Therapy methods using pulsed cavitational ultrasound therapy can include the subprocesses of initiation, maintenance, therapy, and feedback of the histotripsy process, which involves the creation and maintenance of ensembles of microbubbles and the use of feedback in order to optimize the process based on observed spatial-temporal bubble cloud dynamics. The methods provide for the subdivision or erosion of tissue, liquification of tissue, and the enhanced delivery of therapeutic agents. Various feedback mechanisms allow variation of ultrasound parameters and provide control over the pulsed cavitational process, permitting the process to be tuned for a number of applications. Such applications can include specific tissue erosion, bulk tissue homogenization, and delivery of therapeutic agents across barriers.

Abstract: An ultrasonic imaging system acquires echo signals from an object being imaged such as a moving coronary artery and the cross-correlation between echo signals is employed as an objective measure of relative object location. The method is used in a prescan procedure to determine an optimal gating window to acquire image data during a cardiac gated scan, and it is used during the scan as a real time gating signal.

Abstract: A system and method for spectroscopic photoacoustic tomography of a sample include at least one light source configured to deliver light pulses at two or more different wavelengths to the sample. An ultrasonic transducer is disposed adjacent to the sample for receiving photoacoustic signals generated due to optical absorption of the light pulses by the sample. A control system is provided in communication with the ultrasonic transducer for reconstructing photoacoustic tomographic images from the received photoacoustic signals, wherein upon application of light pulses of two or more different wavelengths to the sample, the control system is configured to determine the local spectroscopic absorption of substances at any location in the sample. The system may further provide for one or more of ultrasound imaging. Doppler ultrasound imaging, and diffuse optical imaging of the sample.

Abstract: Therapy methods using pulsed cavitational ultrasound therapy can include the subprocesses of initiation, maintenance, therapy, and feedback of the histotripsy process, which involves the creation and maintenance of ensembles of microbubbles and the use of feedback in order to optimize the process based on observed spatial-temporal bubble cloud dynamics. The methods provide for the subdivision or erosion of tissue, liquification of tissue, and/or the enhanced delivery of therapeutic agents. Various feedback mechanisms allow variation of ultrasound parameters and provide control over the pulsed cavitational process, permitting the process to be tuned for a number of applications. Such applications can include specific tissue erosion, bulk tissue homogenization, and delivery of therapeutic agents across barriers.

Abstract: An ultrasound system comprises an ultrasound probe, a user interface and a processor. The ultrasound probe comprises a transducer face emitting ultrasound beams into a patient. The probe acquires a volume of ultrasound data comprising a blood vessel. The user interface defines a surface on an image that is based on the volume. The surface bisects the blood vessel and further comprises a plurality of points where at least some of the points are located at unequal distances with respect to the transducer face. The processor is configured to steer a subset of the ultrasound beams to intersect the surface at a 90 degree angle and calculate volumetric flow information through the blood vessel based on the ultrasound data corresponding to the surface.

Abstract: A system and method for photoacoustic tomography of a sample, such as a mammalian joint, includes a light source configured to deliver light to the sample, an ultrasonic transducer disposed adjacent to the sample for receiving photoacoustic signals generated due to optical absorption of the light by the sample, a motor operably connected to at least one of the sample and the ultrasonic transducer for varying a position of the sample and the ultrasonic transducer with respect to one another along a scanning path, and a control system in communication with the light source, the ultrasonic transducer, and the motor for reconstructing photoacoustic images of the sample from the received photoacoustic signals.

Abstract: A system and method for photoacoustic guided diffuse optical imaging of a sample include at least one light source configured to deliver light to the sample, at least one ultrasonic transducer disposed adjacent to the sample for receiving photoacoustic signals generated due to optical absorption of the light by the sample, and at least one optical detector for receiving optical signals generated due to light scattered by the sample. A control system is provided in communication with the at least one light source, the ultrasonic transducer, and the optical detector for reconstructing photoacoustic images of the sample from the received photoacoustic signals and reconstructing optical images of the sample from the received optical signals. The priori anatomical information and spatially distributed optical parameters of biological tissues from the photoacoustic images employed in diffuse optical imaging may improve the accuracy of measurements and the reconstruction speed.

Abstract: An x-ray CT system performs a scan by acquiring projection views from which an image is reconstructed. In a prospective embodiment, the correlation of adjacent views is calculated as the scan is performed and is used to detect subject motion as the scan is being performed. In a retrospective embodiment, the correlation of adjacent views is calculated and is used to detect subject motion after the scan is completed. In the first embodiment substitute projection views are acquired by continuing the scan and in the second embodiment redundant projection views acquired during the scan are substituted until the best possible image is produced.

Abstract: The volume of fluid flow within a vessel (VE) is measured by an ultrasound system. Ultrasound waves backscattered from the fluid within the vessel generate data from which velocity values representing components of velocity (Vx and Vy) of the fluid flow in the scan plane (IP) are calculated. Grayscale data is correlated and the rate of decorrelation (D) of the data is calculated. The volume flow of the fluid (F) is estimated in response to the velocity signals and the rate of decorrelation (D).

Abstract: A method and assembly are provided which use cavitation induced by an ultrasound beam for creating a controlled surgical lesion in a selected treatment volume of a patient, such as an internal body cavity or organ. First, a plurality of microbubbles are provided in the treatment volume. Preferably, the threshold for cavitation of microbubbles in the treatment volume is lowered compared with the threshold for cavitation in surrounding tissues. The expected location of the surgical lesion within the treatment volume may be previewed, and then the microbubbles in the treatment volume are cavitated with the ultrasound beam to create the controlled surgical lesion. In addition, substances can be associated with the microbubbles such that cavitation of the microbubbles delivers the substances to the treatment volume. Preferably, the creation of the surgical lesion at the expected lesion location is then verified.

Abstract: A method and assembly are provided which use cavitation induced by an ultrasound beam for creating a controlled surgical lesion in a selected treatment volume of a patient. First, a plurality of microbubbles are provided in the treatment volume. Preferably, the threshold for cavitation of microbubbles in the treatment volume is lowered compared with the threshold for cavitation in surrounding tissues. The expected location of the surgical lesion within the treatment volume may be previewed, and then the microbubbles in the treatment volume are cavitated with the ultrasound beam to create the controlled surgical lesion. Preferably, the creation of the surgical lesion at the expected lesion location is then verified. Using the method and assembly of the present invention, the cavitation threshold within the treatment volume is made predictable, and a low frequency ultrasound beam may be used to cavitate the microbubbles within the treatment volume without causing damage to surrounding tissues.

Abstract: A 3D image data set representing a volume of material such as human tissue is created using speckle decorrelation techniques to process successive 2D data slices from a moving, standard 1D or 1.5D ultrasound transducer. This permits the use of standard ultrasound machinery, without the use of additional slice-position hardware, to create 3D images without having to modify the machinery or its operation. Similar techniques can be used for special data processing within the imaging system as well to expedite the image acquisition process. Optionally, the image quality of 2D images can be enhanced through the use of multiple 3D data sets derived using the method.

Abstract: A method for quantitatively estimating the amount of tissue that contains moving blood using power Doppler ultrasound. A region of interest is identified from a frozen image (i.e., a snapshot screen display created by displaying the last real-time image for a given scan). The region of interest is specified by using a pointing device (e.g., a mouse). An object that contains one hundred percent blood flow and is located at the same depth as the region of interest, but not necessarily inside the region of interest, is identified and the corresponding power noted and designated as the reference power level. The display is adjusted to show the one hundred percent blood flow vessel in a designated color (such as, for example, green) and all other power levels are normalized to the reference power level. The fractional blood volume is quantitatively estimated by summing the normalized Doppler power levels in a region of interest and dividing the sum by the number of pixels in region of interest.