Adaptive refocusing of ultrasound transducer arrays using image data

A dual mode ultrasound transducer imaging or therapy method comprising:

• generating initial image data of a tissue volume in an imaging field of view using an array of ultrasound transducer elements, the array of ultrasound transducer elements being configured to deliver multiband ultrasound energy to the tissue volume including a target region and to receive echo ultrasound energy from the tissue volume, wherein the tissue volume includes an ultrasound distorting obstacle in the imaging field of view and wherein the target region is disposed distal to the obstacle such that at least a portion of the ultrasound energy delivered to one or more target points in the target region must pass through the obstacle;
• determining one or more critical points associated with the obstacle based on the initial image data, wherein the critical points are to be avoided when propagating focused ultrasound energy to the target region;
• determining one or more transmission points associated with the obstacle, each transmission point being different than any of the critical points, wherein the transmission points are to be used for propagating focused ultrasound energy to the target region;
• generating focused image data of the tissue volume including the target region and the obstacle using the array of ultrasound transducer elements, the focused image data comprising information associated with one or more of the transmission points for a plurality of different frequency bands within a bandwidth of the array of ultrasound transducer elements;
• determining one or more efficient frequency bands for one or more of the transmission points based on the focused image data;
• and
• synthesizing excitation waveforms for delivering refocused ultrasound energy to the one or more target points in the target region based on one or more of the transmission points and one or more associated efficient frequency bands.

A dual mode ultrasound transducer imaging or therapy method comprising:

• generating initial image data of a tissue volume in an imaging field of view using an array of ultrasound transducer elements, the array of ultrasound transducer elements being configured to deliver multiband ultrasound energy to the tissue volume including a target region and to receive echo ultrasound energy from the tissue volume, wherein the tissue volume includes an ultrasound distorting obstacle in the imaging field of view and wherein the target region is disposed distal to the obstacle such that at least a portion of the ultrasound energy delivered to one or more target points the target region must pass through the obstacle;
• determining one or more first virtual elements of a first virtual array associated with a distal surface of the obstacle based on the initial image data;
• determining one or more second virtual elements of a second virtual array associated with a proximal surface of the obstacle based on the initial image data;
• estimating a first propagation operator between the one or more of the target points in the target region and the one or more second virtual elements of the first virtual array;
• estimating a second propagation operator between the one or more first virtual elements and the one or more second virtual elements based on the initial image data;
• estimating a third propagation operator between the one or more second virtual elements and one or more of the ultrasound transducer elements of the array;
• and
• configuring the delivery of refocused ultrasound energy to the one or more target points in the target region by solving an optimization problem on a cascade of the first, second, and third propagation operators or solving an optimization problem for each of the first, second, and third propagation operators.