A Harmonic Motion Imaging (HMI)clinical System for Detection and Characterization of in Vivo Human Breast Masses - Initial Feasibility

Harmonic motion imaging (HMI)has been previously proven as a successful imaging technique to measure the relative stiffness of normal and abnormal tissues of postsurgical human breast. The objective of this study was to evaluate the potential of HMI to measure the relative stiffness of tissue in patients with breast masses. The HMI clinical system was composed of an assembly of two co-aligned imaging and focused ultrasound transducers that was moved using a robotic arm to scan a female patient with a suspicious breast mass before needle biopsy. The average of peak-to-peak HMI displacement amplitude in the tumor was estimated and determined to be twice greater than that in non-cancerous breast tissue. Good agreement was found between the size of the tumor measured on the B-mode image and on the HMI displacement image. Our findings indicate that HMI is capable of detecting and assessing elasticity variation of in vivo human breast tissue as a result of pathological changes.