With the booming of physics and technologies, the demand for medical use is increasing rapidly, and radiation therapy is one of the most widely used technologies. Doctors and hospitals monitor, diagnose, and treat diseases and metabolic processes in humans by using a variety of nuclear materials and technologies. The research indicates that the radiotherapy plays an really important role in the area of medicine. But what is the physics theory behind it? And what is the concept of the technology?
When particles are emitted from nuclei, the nucleus will experience the intense conflict between the two strongest forces in nature (strong nuclear force and electromagnetic force), then many nuclear isotopes will become unstable and emit radiation; …show more content…
Beta radiation is a stream of electrons, when a beta particle is sprayed, a neutron is converted to a proton, so the mass number remains the same while the atomic number increases by one unit. And gamma rays consist high-energy photons with a relatively short wavelength (0.0005 ~ 0.1 nm). The particles emitted in radioactive decay processes have high kinetic energy, which is enough to ionize an atom or a molecule; especially photons, which can ionize atoms and molecules through the photoelectric effect and Compton scattering. And if the radiation is sufficiently intense, the speed of destroying molecules is faster than coping them, which can cause harmful chemical damages to healthy cells and even to DNA. But on the other hand, the damaging effects of radiation can used to kill the rapidly growing cancerous cells. Radiotherapists can localize the source of damage and minimize the effect on the surrounding tissue. For example, external beam therapy is used to direct towards the affected part …show more content…
At the beginning of the 20th century, with the development of chemotherapy, doctors and scientists started using radiation to treat growths and lesions caused by diseases. But experimenters found that a long-term exposure to x-rays would cause inflammation and tissue damage on the skin. Marie Sklodowska Curie isolated the first known radioactive elements, Polonium and Radium. She and her husband won the Nobel Prize in Physics in 1903, but they both died because of the therapeutic potential of radiation. Over the next fifty years, a number of technological developments had allowed radiologists to target the x-ray beam more accurately and avoid damaging normal tissue, further improving radiotherapy as a cancer treatment. For instance, Conformal radiation therapy (CRT) uses CT images and special computers to determine the accurate shape and size of the tumor. A technique called brachytherapy treat cervical and uterine cancers by placing tiny beads or rods of metal with radioactive properties around the tumor. This technology is still in use today but with cesium and iridium