Features And Benefits Of The Radiation Therapy - Essay Example

Features And Benefits Of The Radiation Therapy Question 1 The linac is now one of the most important inventions in the world. The liner particle accelerator can be defined as an electrical device for the acceleration of subatomic particles. The linac may be applied for different purposes but id like to tell about the most important one: the generation of X-rays. X-rays play a crucial role in medical diagnosis. In my work I will tell you about the particular use of X- rays Radiation therapy (or radiotherapy) is the medical use of ionizing radiation as part of cancer treatment to control malignant cells . (www.wikipedia.org) Radiotherapy specialists should possess great skills in physics, medicine and also extraordinary attention is required as there are a great number of parameters that should be defined such as gantry angle, collimator rotation field size and so on. But radiographers are ordinary people who are able to make mistakes. In this case ‘human error” will be fatal for the patient. So the main purpose of the use of verification systems to reduce or even to overcome the human error. According to the speakers of the meeting named “verification systems tools or toys” from the patient’s point of view the verification systems seemed to be a plus because they permit increasingly sophisticated treatment to be delivered with greater accuracy at a grater speed. Currently verification systems are considered as separate equipment are bid for an addition to liner accelerator and managers have to be persuaded of the additional benefits. making verification system as a standard component of the LinAC is strongly wished because it will ensure universal availability. (the British journal of radiology 71 1998) Now let me tell you a few words about Lue- 200 verification system. It wwas developed by joint institute for nuclear research in Dubna. The hardware decisions are based on Personal computers and programmable logic controllers. As the software SCADA System and package for PLC programming under the standard IEC1131 is used. Also some training courses to increase should be organized, providing some information about the main functions of the system and some important information such as parametrs and necessary dose of X-Rays. Question 2 The radiation may cause damage that’s why the patients are not usually treated by X-rays more often than one a year. The amount of radiation used in radiation therapy is measured in grays (Gy), and varies depending on the type and stage of cancer being treated. For curative (radical) cases, the typical dose for a solid epithelial tumor ranges from 50 to 70 Gy, while lymphoma tumors are treated with 20 to 40 Gy. Preventative (adjuvant) doses are typically 20 to 25 Gy. But there are extra cases when it’s strongly recommended and the damage must be minimized. Nowdays scientists at the Royal Marsden Hospital in London are testing a system called intensity modulated radiotherapy (IMRT), in which the doses of radiation are controlled precisely to minimise this unwanted damage. An enhancement of virtual simulation is 3-Dimensional Conformal Radiotherapy (3DCRT), in which the profile of each radiation beam is shaped to fit the profile of the target from a beam's eye view (BEV) using a multileaf collimator (MLC) and a variable number of beams. When the treatment volume conforms to the shape of the tumour, the relative toxicity of radiation to the surrounding normal tissues is reduced, allowing a higher dose of radiation to be delivered to the tumor than conventional techniques would allow.(http://www.wikipedia.org) Question 3 In our hospital was admised a man suffering from awful pains. After admission of this patient he was examined and cancer was unfortunately diagnosed. Doctor Brant recommended ablation of urinary bladder and insertion of catheter. The operation took only two hours the ablation was affected successfully. Three days the patient was in the bed after that he was examined the second time. His state was defined as satisfactory but in order to exclude metastases he was prescribed radiotherapy. Mr Robinson was a very courageous man but after some courses he was in frustration because of the permanent sickness and growing bald A psychologist Mr McNamara had been working with him for a week and he managed to persuade him to pool himself together. In addition to psychological aid he attended some physical training in order to regulate urination. After 2 months of being treated in this hospital he was discharged. And now he feels good and thanks God for giving him such a good team of specialists. Question 4 Our patient is a forty year old man. He has been smoking for nearly twenty years. At first he was hospitalized because of the pneumonia. In the hospital he was given antibiotics. A fortnight latter he felt better and came back home. But his doctor strongly recommended him to give up smoking and the patient was explained that smoking could cause lung cancer. Despite the interdiction the patient even increased quantity of cigarettes. And six month letter he was hospitalized again. After looking at the patient a doctor decided to affect a biopsy because the ill was very pale suffered from excessive sweating and had lost 10 kilograms during one month without keeping a diet. Under anesthesia a sample of tissue in the patient’s lung was removed and the cancer diagnosed after analyzing the sample under microscope. After the consultation a set of procedures was defined. First of all the ablation off the tissue also the radiotherapy was prescribed in order to exclude recurrence . A team of specialists took every precaution to minimize the radiation dose because sometimes the radiation could cause leucosis and other diseases. During the treatment the patient was being provided special psychological aide that encouraged him to fight the cancer. Question 6 It’s evident that the X-rays are the main instrument for cancer treatment. But the radiation tends to accumulate in the body and causes damage. Usually it is used to destroy the tissue but sometimes it destroys normal blood cells. It may provoke a very grave disease named leocosis Harmful biological effects, caused by ionising radiation, which do not have a dose threshold, whose probability is proportional to the dose and for which the seriousness in their manifestation does not depend on the dose. To the stochastic (probabilistic) effects without threshold belong in particular malicious tumours, leucosis, and heritable diseases.  (www.chernobyl.info./index php That disease can be defined as a lack of red blood cells. Such cells provide oxygen to all the body. That’s why the radiation dose mustn’t be over 110 kv. Task 1 There are some parameters that must be strongly defined and controlled The radiation dose absorbed by the treated mass of tissue is what defines the degree of biological inactivation. It usually is measured in grays, where one gray (Gy) is the absorption of one joule per kilogram of mass. A unit that attempts to take into account both the different organs that are irradiated and the type of radiation is the sievert, a unit that describes both the amount of energy deposited and the biological effectiveness.(www.wikipedia. Org) Collimator is a part of the linac that causes a beam of radiation, as light, to move as parallel rays. So its rotation must be strongly defined. As a conclusion I’d like to tell you about the Manchester system. This system is usually used to define a dosage. According to this system the dose to all parts of the target volume is within 10% of the prescription dose. Task 2 Brachytherapy, also known as sealed source radiotherapy or endocurietherapy, is a form of radiotherapy where a radioactive source is placed inside or next to the area requiring treatment. Conversely, external beam radiotherapy, or teletherapy, is the application of radiation that has been externally produced by a linear accelerator. Brachytherapy is commonly used to treat localized prostate cancer and cancers of the head and neck.(www.wikipedia.org ) In our case the patient suffers from the prostate cancer. He suffered from pains erectial dysfunction and difficulty in urinating. The brachyterapy is commonly used for this type of cancer instead of surgery for early cancers and this patient had the early stage of the cancer That’s why the recommended type of the treatment is interstitial brachytherapy. According to this system modern specialists tend to use iridium-192 wire. Prostate cancer is treated with iodine 125. And the radiotherapy should be combined with the hormonal therapy used to block the prostate cancer cells from getting special hormone required for the growth and spread of such cells. For this purpose our patient was given some special medicaments which directly blocked the action of testosterone and DHT within cancer cells. Owing to early diagnosis and appropriate care our patient was saved. Task 4 Each radiotherapy treatment parameter, as defined by the radiographer i.e. gantry angle, collimator rotation, field size and so on is required to be verified by the system. Habitually they are entered in the computer. But every computer as any other technique may be damaged. The radiotherapy with the patients so each mistake may be crucial. In order to reduce the human error we use a special dosimeter program. UNIDOS is well known and accepted worldwide as the dosemeter of choice with best performance available on the market. The new UNIDOSwebline sets another milestone in dosimetry. It is a high precision secondary standard reference class dosemeter combined with modern network features. The ethernet interface based on the TCP/IP protocol allows to integrate the UNIDOSwebline in a LAN for remote access and E-mail capability. Its big, user-configurable TFT display garanties visibility from wide angles. A comprehensive chamber library makes it possible to store the calibration data of the chambers. Air density corrections are done by keying in air pressure and temperature, or by means of radioactive check devices. The check device data are stored in a database. An internal clock calculates the decay of the isotope radioactivity. It features both mains and battery operation. The delivery includes a manual in English.(www.ptw.de/index ph) Sources 1 www.ptw.de/index 2 www.wikipedia.org. 3 www.chernobyl.info./index Read More