The radiotherapy uses a much more intense form of radiation than X-rays. To put this into perspective, a radiotherapy machine will use 60-80,000 volts to produce the x-ray, a linear accelerator will use 6,000,000 - 20,000,000 volts. The machine then takes this voltage and converts it to X-rays or electrons, these are then refined and aimed so that only a single energy is used, focussed on a specific target point. The beam can be changed in size and shape but not intensity and so, to tailor the treatment for any one person, modifications are made to how it is positioned. The duration for which it is kept on, determines the total dose that is delivered. The dose of radiation is measured in Gray (abbreviated to Gy).
Linear accelerator ThoraScan™:
ThoraScan™ offers a revolutionary new way to digitally capture the thorax and uses the most efficient slot-scan technology ever designed. Its unsurpassed image quality is achieved by a 1 cm-thick, fan- shaped X-ray beam in combination with a multi-linear, scanning, solid-state X -ray detector. This unique image acquisition dramatically reduces scatter radiation, eliminating the need for a grid thus lowering patient dose. The new system has an effective exposure time of 20 ms, delivering unsurpassed image quality with all the associated workflow advantages of a direct digital system.
ThoraScan™ Digidelca-M:
The considerable increase of tuberculosis in the world is making it necessary to pay more attention to its prevention. A good method of identifying and reducing the impact of this disease is mass chest screening. Oldelft has been active in the field of tuberculosis screening since 1950. This latest screening system by Nucletron is a digital camera which has been developed from past systems such as the Electrodelca and Odelca. Benefits include a reduction in radiation from its predecessors and the cost-effectiveness of filmless screening.
7. A look into the future
Several new approaches to radiation therapy are being evaluated to determine their effectiveness in treating cancer. One such technique is intraoperative irradiation, in which a large dose of external radiation is directed at the tumor and surrounding tissue during surgery.
Another investigational approach is particle beam radiation therapy. This type of therapy differs from photon radiotherapy in that it involves the use of fast-moving subatomic particles to treat localized cancers. A very sophisticated machine is needed to produce and accelerate the particles required for this procedure. Some particles (neutrons, pions, and heavy ions) deposit more energy along the path they take through tissue than do x-rays or gamma rays, thus causing more damage to the cells they hit. This type of radiation is often referred to as high linear energy transfer (high LET) radiation.
Scientists also are looking for ways to increase the effectiveness of radiation therapy. Two types of investigational drugs are being studied for their effect on cells undergoing radiation. Radiosensitizers make the tumor cells more likely to be damaged, and radioprotectors protect normal tissues from the effects of radiation. Hyperthermia, the use of heat, is also being studied for its effectiveness in sensitizing tissue to radiation.
Other recent radiotherapy research has focused on the use of radiolabeled antibodies to deliver doses of radiation directly to the cancer site - radioimmunotherapy. Antibodies are highly specific proteins that are made by the body in response to the presence of antigens (substances recognized as foreign by the immune system). Some tumor cells contain specific antigens that trigger the production of tumor-specific antibodies. Large quantities of these antibodies can be made in the laboratory and attached to radioactive substances (a process known as radiolabeling). Once injected into the body, the antibodies actively seek out the cancer cells, which are destroyed by the cell-killing (cytotoxic) action of the radiation. This approach can minimize the risk of radiation damage to healthy cells. The success of this technique will depend upon both the identification of appropriate radioactive substances and determination of the safe and effective dose of radiation that can be delivered in this way.
8. Conclusion
We can cure many types of cancer today. The chance for absolut recovery is depending on the stage of the disease. If the stage of cancer is developed, the treatment is quite long and not effective enough. The cancer in high developed stage is the reason of such high mortality from it.
