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 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.