When X-rays were discovered, mankind has experienced
After irradiation, in many patients the tumor decreased in size, the disease receded. On the adverse effects of radiation on normal cells and tissues became known later, and "reputation" radiation Therapy was severely damaged. Its use has dropped significantly. But it turned out that the water threw the baby out, forgetting the undoubted success of radiotherapy in the treatment of cancer patients. Over time, have developed the least traumatic patterns of use of radiation and radiation therapy has become an integral part of the treatment of tumors.
Radiation therapy today
Radiation therapy — A therapeutic effect on cancer cells to ionizing radiation. The clinics are used ordinary X-rays of very high energy or electron beams.
How does the quantum of living cells on a strong X-ray radiation or overclocked to high speed electron? Having met on the way a molecule, it breaks its electronic structure. Such molecules are no longer perform its function in a complex intracellular metabolism. As a result, the cell either dies or loses its ability to divide.
Tumor tissues were the most vulnerable, because the intense cell division makes them particularly sensitive to the effects of radiation. Therefore, a sufficiently large dose of radiation absorbed by the tumor stops its development. In some cases, conventional surgery may not be necessary.
However, radiation therapy usually does not pass completely to the patient — he has a weakness, nausea, it may poredet hair, generally decreases the body's resistance to infection. That is, despite the positive results of treatment, the consequences for a long time to recover.
Something similar happens with chemotherapy, when, in order to work on one small area of the body, medical supplies necessary to "poison" the entire body. However,radiation therapy has an advantage — it allows aiming to beat it by the tumor.
Is it possible to strengthen and develop this asset? This is particularly necessary if near the tumor located vital organs. In order to accurately strike at cancer, you need to know the details of its shape and location. If we restrict the study of X-ray images and manually send totumor radiation source, it's like fire "by eye." A miss is inevitable, will suffer as a result of normal tissue. It is therefore necessary to focus the beam and direct it to the tumor, without deviating a millimeter. Such work may be performed only unmistakably modern automatics.
How modern systems for radiation therapy?
The unit conducts preliminary "zeroing" — makes a simple X-ray image and displays the results on screen. In this shot the doctor with arm exercises marking the tumor, indicating its limits and plans to radiation exposure. Then he can only transfer control to an automated system and it will do everything herself: will push the patient, emitting head turn and set up metal shutters collimator so that tumor will be under the gun. The accuracy with which the procedure is performed, it is impossible to achieve manually.
If the tumor borders are vague, blinds during irradiation session change shape so that the largest dose of radiation absorbed by the areas with the highest concentration of cancer cells.
During the preliminary "zeroing" in the patient's body by laser lights cross, this place is a nurse observes the marker. When moving to another machine laser crosshair is aligned with marker marks, and the computer automatically calculates the necessary correction.
But what if under attack are not only the tissue around the tumor, but also for her? How to reduce the dose of radiation absorbed by healthy tissue?
To do this, the computer does not indicate a flat contour and three-dimensional "body of work". This is possible if the medical staff has to monitor three-dimensional image of the tumor. It is obtained by a tomograph — synthesis X-ray apparatus and the computer.
Unfortunately, to avoid exposure of tissue located between the X-ray tube and tumor impossible because anyway beam must pass through them. In this case, there is a possibility of radiation skin burns, especially for old phones. More modern technology provides protection against burns.
But today, it is really to minimize the exposure of the tumor tissue. And it is the task of the system — to calculate the parameters of the radiation so that it is almost completely absorbed by the "body" of the tumor, no matter how complex shape it is.
In the future, these systems fully automate and subject to one central computer. A doctor will only work situation analysis and decision making.