Abstract: A method for mapping shear wave velocity in biological tissues includes using an ultrasound transducer to generate mechanical excitations at a plurality of locations in a region of interest. An MRI system is used to capture a phase image of each mechanical excitation, wherein motion encoding gradients (MEGs) of the MRI system encode a propagating shear wavefront caused by the mechanical excitation. A plurality of shear wave velocity maps is generated based on the phase images, wherein each shear wave velocity map depicts velocity between adjacent propagating shear wavefronts. The shear wave speed values are combined to generate a composite shear wave velocity map of the region of interest.

Abstract: A computer implemented method for measuring T1 in an anatomical region of interest during a dynamic procedure includes acquiring a reference MR image of the anatomical region of interest using a first flip angle. A first set of dynamic MR images of the anatomical region of interest are acquired using a second flip angle. The reference MR image and the first set are used to calculate a reference T1 value for tissue in the anatomical region of interest. During an intervention where the T1 value may change, a second set of dynamic MR images of the anatomical region of interest is acquired using the second flip angle. The reference MR image and the second set are used to calculate an estimated T1 value. The reference T1 value, the estimated T1 value, and the first and second flip angles may then be used to correct the estimated T1 value.

Abstract: A therapeutic ultrasound breast treatment device (101) is disclosed. The device (101) can include a receptacle (130) to receive a breast of a patient therein. The device (101) can also include an ultrasound transducer assembly disposed proximate the receptacle and oriented to direct a high intensity ultrasound transmission through an opening (168) of the receptacle (130) toward the breast. The device (101) can include a liner (1 60) disposed in the receptacle (130) to contain an ultrasound coupling fluid about the breast. The liner (160) can have an extension portion that extends through the opening (168) to form a seal with the ultrasound transducer assembly to prevent leakage of the ultrasound coupling fluid. A focus location of the ultrasound transmission can be adjustable and the device (101) can include a plurality of RF tracking coils to determine the focus location of the ultrasound transmission to facilitate adjustment of the focus location in an MRI environment.

Abstract: A computer implemented method for measuring T1 in an anatomical region of interest during a dynamic procedure includes acquiring a reference MR image of the anatomical region of interest using a first flip angle. A first set of dynamic MR images of the anatomical region of interest are acquired using a second flip angle. The reference MR image and the first set are used to calculate a reference T1 value for tissue in the anatomical region of interest. During an intervention where the T1 value may change, a second set of dynamic MR images of the anatomical region of interest is acquired using the second flip angle. The reference MR image and the second set are used to calculate an estimated T1 value. The reference T1 value, the estimated T1 value, and the first and second flip angles may then be used to correct the estimated T1 value.

Abstract: A method for mapping shear wave velocity in biological tissues includes using an ultrasound transducer to generate mechanical excitations at a plurality of locations in a region of interest. An MRI system is used to capture a phase image of each mechanical excitation, wherein motion encoding gradients (MEGs) of the MRI system encode a propagating shear wavefront caused by the mechanical excitation. A plurality of shear wave velocity maps is generated based on the phase images, wherein each shear wave velocity map depicts velocity between adjacent propagating shear wavefronts. The shear wave speed values are combined to generate a composite shear wave velocity map of the region of interest.

Abstract: A method for producing an image of a subject using a magnetic resonance imaging (MRI) system includes acquiring a series of echo signals by sampling k-space along radial lines that each pass through the center of k-space. Each projection of the radial lines is divided into multiple echoes and successive projections are spaced by a predetermined angular distance. The series of echo signals are reconstructed into a plurality of images, wherein each image corresponds to a distinct echo signal.

Abstract: A technology is described for multipoint tissue elastic property measurement. An example method (700) 700 includes generating a treatment map (710) of an anatomical region that shows focal points within the anatomical region to be exposed to Focused Ultrasound (FUS) pulses; acquiring a reference MR-ARFI image (720) of the anatomical region containing the focal points using the treatment map; acquiring an active MR-ARFI image (730) for each of the focal points in the anatomical region during exposure of the focal points to the FUS pulses using the treatment map; interleaving the reference MR-ARFI image and active MR-ARFI images (740) to create a combined image of the anatomical region and the focal points; and calculating a tissue displacement measurement (750) for the focal points exposed to the simultaneous and/or rapidly interleaved FUS pulses using the combined image of the anatomical region and the focal points exposed to the simultaneous FUS pulses.

Abstract: A method for producing an image of a subject using a magnetic resonance imaging (MRI) system includes acquiring a series of echo signals by sampling k-space along radial lines that each pass through the center of k-space. Each projection of the radial lines is divided into multiple echoes and successive projections are spaced by a predetermined angular distance. The series of echo signals are reconstructed into a plurality of images, wherein each image corresponds to a distinct echo signal.

Abstract: A therapeutic ultrasound breast treatment device (101) is disclosed. The device (101) can include a receptacle (130) to receive a breast of a patient therein. The device (101) can also include an ultrasound transducer assembly disposed proximate the receptacle and oriented to direct a high intensity ultrasound transmission through an opening (168) of the receptacle (130) toward the breast. The device (101) can include a liner (1 60) disposed in the receptacle (130) to contain an ultrasound coupling fluid about the breast. The liner (160) can have an extension portion that extends through the opening (168) to form a seal with the ultrasound transducer assembly to prevent leakage of the ultrasound coupling fluid. A focus location of the ultrasound transmission can be adjustable and the device (101) can include a plurality of RF tracking coils to determine the focus location of the ultrasound transmission to facilitate adjustment of the focus location in an MRI environment.

Abstract: MRI-guided high-intensity focused ultrasound (“HIFU”) therapy can be used to ablate sympathetic nerves near the renal arteries. Such therapy may employ a HIFU device that includes an ultrasound transducer and an expandable reservoir that includes a first surface configured to conform to a surface anatomy of a patient and a port in fluid communication with a fluid source. The expandable reservoir can be configured to change a size in a dimension by inflating or deflating the expandable reservoir. Such a device may be used in connection with an MRI device that includes a support portion configured to conform to the surface anatomy of the patient and defining a first window configured to receive the ultrasound transducer for targeting tissue. The MRI device can include radiofrequency coil arrays embedded throughout to the support portion to monitor the therapy.

Abstract: Non-invasive, outcome-confirmed renal denervation procedures include assessments performed before, during, and after an ablation procedure. Stimulation operations can be performed by ultrasound application apart from ablation and/or heating operations to determine the presence and/or condition of a renal nerve in a targeted region. Consistent nerve ablation can be achieved (e.g., in a spontaneous hypertensive patient) by assessing the pathophysiology of renal denervation via (1) reduction of blood pressure and/or (2) kidney and serum norepinephrine concentration.

Abstract: A method of treating hypertension in a mammal is described, including: by focused sound energy, heating at least one nerve at a surface of a renal artery in a mammal; during the heating and by magnetic resonance imaging, repeatedly determining thermal levels in each of first and second volumetric zones of a region that includes at least a portion of the surface, the second zone being adjacent to the first zone; after determining that an indicium of a thermal level in the first zone exceeds a first threshold, and upon determining that an indicium of a thermal level in the second zone exceeds a second threshold, ceasing the heating of the at least one nerve for at least three months; and as a result of the heating, lowering a blood pressure in the mammal.