Author: Aldanova Aziza
As everyone knows, X-rays pass through soft tissue, like skin and internal organs, but not through dense tissue, like bone. Now, new technology of radiography can identify soft tissue and tumor damage earlier than an MRI or ultrasound scan. Scientists from Tohoku, University Japan shared a new X-ray resolution, the results of which were published in March in the journal Applied Physics Express. It will facilitate undoubtedly the work of medical staff and expand the range of elastography technology. Elastography is a non-invasive imaging method that displays the elastic modulus of materials, which was developed using magnetic resonance imaging and ultrasound. However, X-ray elastography has been little studied, which has promoted to the propagation of “transverse waves".
Previous studies have only suggested the possibility of X-ray elastography, but this is the first case that has been able to confirm the visualization of real rigidity using this concept. The frequency of ultrasound reaches from 2 to 29 Mhz, much more than people can hear (for humans, the nominal frequency of the wave ranges from 16 to 20 kHC). Accordingly, ultrasound of scan works by sending “transverse waves” through us, they can be compared with sound, twitching the rope up or down. “Transverse waves” propagate faster through “hard” tissues, compared to “soft” ones. For example, the tissues of a malignant tumor, a liver affected by cirrhosis, and a hardened artery are stiff, and the waves pass through them more slowly, which allows the doctor to identify healthy tissue from unhealthy. MRI works similarly, but by using a strong magnetic field, it forces the protons in the human body to align with this field. But the course of protons takes a long time, when the replacement is a more simplified form, from dense to soft tissues.
Now this technique is also possible with X-ray. Polyacrylamide gel phantoms (PAAG) were vibrated pneumatically, as a result of which scientists obtained two-dimensional map models (UV coordinates) of accumulation and loss, which were determined by temporarily changing the motion vectors of the phantom vibrating particles. This allowed to researches to provide storage modules with an accuracy of 30%, and the spatial resolution was much higher than other visualization methods. It should be noted that x-rays can provide a greater resolution than ultrasound, on the order of micrometers (millionth of a meter) instead of millimeters (simple thousandths of a meter). According to the lead researcher, associate professor at the Institute of Interdisciplinary Research in Advanced Materials (IMRAM) of the University of Tohoku - Wataru Yashiro, this technology does not only allow to determine the depth of damage in a particular organ, but also speaks of the importance of recognizing lesions when they occur or during early illness. The next step is the creation of 3D visualization, for the further development of technology. As a result, they want to make medical diagnostic equipment for x-ray elastography.
The spectrum of elastography is still limited by protons on the basis of the magnetic field and ultrasound. However, we can hope that the new technology will allow patients and doctors to conduct early and accurate diagnostics, which will improve the course of events and minimize ionizing radiation.
