Fig. 4.

Harmonic motion imaging for focused ultrasound (HMIFU) ablation monitoring in 2D overlaying on B-mode images in (a) normal breast and (b) IDC tissue. Tissue motion during heating is denoted by alternating red and blue. Red represents the motion moving toward the transducer, and blue represents the motion moving away from the transducer. Peak negative harmonic motion imaging displacement frames during a 50-Hz cycle at five representative timepoints were selected from the HMIFU treatment monitoring sequence to show the decrease of focal displacement as the thermal lesion forms