Figure 7.
Example of using the positioning system to perform scanned ultrasound heating with simultaneous MR thermometry. The top row shows the maximum temperature distribution measured in excised turkey breast with (a) the positioner stationary, (b) moving in a circular path with a 2.5 mm radius and a period of 1 s, and (c) moving in the same circular path with 10 W of acoustic energy delivered for 60 s in order to produce a large heating pattern. No ultrasound energy was delivered in (a) or (b). The bottom row shows the mean temperature of a 5×5 mm2 ROI that depicts the minimal impact presented by the motion of the positioning system on the MR thermometry measurements.