A therapeutic apparatus (300, 400, 500) comprising a high intensity focused ultrasound system (302) comprising an ultrasound transducer (306). The ultrasound transducer has an electronically adjustable focus (318). The high intensity focused ultrasound system has a beam deflection zone (322, 608, 704, 1010). The intensity of ultrasound at the electronically adjustable focus divided by the acoustic power emitted is above a predetermined threshold (606, 1008) within the beam deflection zone. The therapeutic apparatus further comprises a processor (328) for controlling the therapeutic apparatus. Execution of machine executable instructions (350, 352, 354) causes the processor to: receive (102, 202) real time medical data (342, 424, 506) descriptive of the location of a moving target (320, 802)； adjust (104, 204) the electronically adjustable focus to target the moving target using the real time medical data； and sonicate (106, 206) the moving target when the moving target is within the beam deflection zone.
