Treatment acceleration by modification of sound fields and sonication modalities

High intensity focused ultrasound can produce a small tissue necrosis deeply inside the body. By setting several of these lesions next to each other a larger volume, e.g. a tumor, can be coagulated non-invasively. Normally the tumor which has to be treated has a volume of several cm³, whereas a single ultrasound lesion typically has only a volume of a few mm³. Therefore, a lot of single ultrasound shots are needed to treat the whole tumor, resulting in a long treatment time. In this study several approaches were investigated to reduce the time. Therefore we have investigated several methods: lenses, a different sonication order and ultrasound exposure during transducer movement. We achieved results comparable to the normal treatment, while the treatment time was reduced by a factor of more than eight