Figure 3

Isolated regions of coagulated BSA within the phantom caused by focalheating with the 3.23-MHz transducer. The test was performed in thex‒z direction (left) and thex‒y direction (right) to measure theseparation between individual sonications. The precision of targeting wasapproximately 0.01 mm, and the accuracy was less than 2%. The greatesterror occurred in the z direction which is due to the difference inspeed of sound between the coupling water and phantom and the different amountsof each in the beam path with different focal depths.