Various approaches for regulating microbubbles in a treatment procedure for a target include generating a tissue-sensitivity map including multiple regions, at least one of the regions being outside the target region, the tissue-sensitivity map assigning, to each of the regions, a sensitivity level indicative of tissue sensitivity to the interaction between the microbubbles and an acoustic beam； select one or more interaction regions based at least in part on the tissue-sensitivity map； and activating the ultrasound transducer so as to generate the acoustic beam for interacting with the microbubbles in the selection interaction region(s) in the tissue-sensitivity map, thereby indirectly changing a characteristic of the microbubbles at the target region.
