Harmonic Motion Imaging (HMI) for Tumor Imaging and Treatment Monitoring

Abstract

Palpation is an established screening procedure for the detection of several superficial cancers including breast, thyroid, prostate, and liver tumors through both self and clinical examinations. This is because solid masses typically have distinct stiffnesses compared to the surrounding normal tissue. In this paper, the application of Harmonic Motion Imaging (HMI) for tumor detection based on its stiffness as well as its relevance in thermal treatment is reviewed. HMI uses a focused ultrasound (FUS) beam to generate an oscillatory acoustic radiation force for an internal, non-contact palpation to internally estimate relative tissue hardness. HMI studies have dealt with the measurement of the tissue dynamic motion in response to an oscillatory acoustic force at the same frequency, and have been shown feasible in simulations, phantoms, ex vivo human and bovine tissues as well as animals in vivo. Using an FUS beam, HMI can also be used in an ideal integration setting with thermal ablation using high-intensity focused ultrasound (HIFU), which also leads to an alteration in the tumor stiffness. In this paper, a short review of HMI is provided that encompasses the findings in all the aforementioned areas. The findings presented herein demonstrate that the HMI displacement can accurately depict the underlying tissue stiffness, and the HMI image of the relative stiffness could accurately detect and characterize the tumor or thermal lesion based on its distinct properties. HMI may thus constitute a non-ionizing, cost-efficient and reliable complementary method for noninvasive tumor detection, localization, diagnosis and treatment monitoring.

Thermometry and ablation monitoring with ultrasound

“…Using GPU processing, real-time harmonic motion imaging has been reported (129). A review of results and progress with this technique was recently published by Konofagou et al (130). …”

Supersonic transient magnetic resonance elastography for quantitative assessment of tissue elasticity

“…ARF impulse (ARFI)-induced shear wave imaging has been implemented on commercial diagnostic ultrasound scanners and applied in human studies (Palmeri et al 2008). The ARF excitation can be transient, as applied here, or harmonic (Urban et al 2011, Konofagou et al 2012). …”

Acoustic Radiation Force Impulse (ARFI) Imaging: A Review

“…Elasticity imaging methods involving acoustic radiation force have been under investigation for several years, e.g., (2; 3; 4; 5; 6; 7; 8), and many are presented in detail in this special issue (9; 10; 11; 12). These methods offer some advantages over those requiring external excitation: the force is applied directly to the region of interest, thus smaller stresses are used, and challenges associated with coupling the excitation to the desired tissue region are diminished.…”