Elastography in sometimes referred as seismology, is an emerging technology used to enhance medical ultrasound imaging. The technology measures the elasticity of biological tissue to diagnose cancer or liver and thyroid diseases. More accurately at the earliest stages.
In passive elastography, the elasticity of tissue is measured using the body’s own propagation of shear waves. Which enables more effective imaging deeper inside the body in an even more noninvasive way than traditional elastography.
“Passive elastography is foreseen as a viable technique for cancer detection in the body, and for fragile organs, such as the eye,” said, Stefan Catheline from University of Lyon, France.
In seismology, Shear waves (S-waves) generates pressure during an earthquake. In medical science, shear waves produced by vibration devices to measure the stiffness of tissue.
A cancerous tumor and other tissue dysfunction exhibit much higher stiffness than in healthy tissue or even in benign tumors. The difference in stiffness cannot change or seen in conventional ways or through other imaging methods.
Typically, a medical technician places a probe with a vibrating mechanism in the area for testing and presses down to produce the shear waves, which then interact with the tissue in question. The waves tracked at ultrafast imaging rates. The shear waves difficult to produce in hard to reach organs.
To solve, researchers analyze noise of natural shear waves produced biologically. Just as in earthquakes, shear waves move through organs and other soft tissue of a person during the everyday functionalities of bodily systems, such as the beating of a heart or the liver performing everyday metabolic processes.
The idea is to take advantage of shear waves naturally present in the human body due to muscle activities to construct a shear elasticity map of soft tissues, Catheline said. Passive elastography is compatible with slow imaging devices, such as standard echographs and MRI scanners, as well as with optical coherent tomography.