A Simulation Study on the Investigation of Thermal Effects Associated with Acoustic Radiation Force Shear Wave Interference Patterns Generation in the Liver Tissue
Purpose: The mechanical map of liver tissue like stiffness is as important as its anatomical image for clinical purposes like staging the liver fibrosis. Acoustic radiation force-based shear waves interference patterns elastography is an interesting independent imaging rate technique which can generate shear waves in the liver tissue in any desired depth by means of the high intensity focused, long duration push beams. Because of wave attenuation and absorption process the sound wave energy is dissipated in the tissue and due to energy conservation law is turned into heat thus like any other ultrasound imaging modality, shear waves interference patterns elastography carries the risk of tissue heating and thermal ablation specially at the focal spot. Therefore, particular attention must be paid to the thermal safety assessment to shear waves interference patterns elastography. The aim of the present simulation study is the thermal safety evaluation in the liver tissue.
Materials and Methods: The liver tissue has been simulated in the presence of its adjacent tissues like skin, muscle, ribs and intercostal muscles in 3 dimensions during shear waves interference patterns elastography. With 4 seconds exposure time and 2 MPa focal pressure.
Results:Temperature at the focal point increases from normal body temperature (37˚C) to 47˚C.
Conclusion: Thermal effects appraisal, indicates that the general tissue heating stays within the safe region.