Sub-aperture control in high intensity focused ultrasound

摘要

Sub-aperture control is provided for high intensity focused ultrasound. Test transmissions are made sequentially from different sub-apertures. The tissue response at the focal regions is determined and used to select sub-apertures. For example, one or more sub-apertures are not used where temperature does not rise above certain threshold or tissue displacement is weak, such as associated with intervening bone or attenuating tissue. Other factors may be used instead or in addition to tissue response at the focal region. Relative proximity of the sub-apertures to a lesion, angular distribution of the sub-apertures, shape or size of the sub-aperture focal regions as compared to the tissue to be treated, or combinations thereof may be used. Once selected, the relative weight for each sub-aperture may be adjusted based on measured tissue response for each sub-aperture, such as to provide more equal treatment contribution from different sub-apertures.

主权项

1. A system for sub-aperture control for high intensity focused ultrasound, the system comprising:
a phased array of elements, the array comprising an aperture; a sub-aperture circuit configured to activate and deactivate sub-arrays of the elements, the sub-arrays being sub-apertures of the aperture, each of the sub-apertures being less than all elements of the aperture; a processor configured to control the sub-aperture circuit so that the sub-aperture circuit is configured to select some of the sub-apertures and not select others of the sub-apertures, the selection being as a function of a distribution, at a target to be treated, measured with ultrasound transmissions from the sub-apertures; and a beamformer having channels configured to connect with respective elements of the sub-apertures and to separately beamform for each of the sub-apertures and not beamform for the others of the sub-apertures.