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Records of dose parameters in radiodiagnostic workplaces - contemporary state
MRÁZOVÁ, Monika
The theoretical part of the thesis deals with the characteristics of ionizing radiation. It explains the interaction of ionizing radiation with substance and cells. Attention is also paid to the mechanism of damage caused to the cells of the human body. It explains the basic principles of radiation protection. The paper describes the function of the ionization chamber, as the most common device used in dosimetry of ionizing radiation. A large section is devoted to formulas, which are routinely used to determine the effective doses. It explains basic indicator of obesity, body mass index, which has a significant impact on the dose received by a patient during examination. At the end of the theoretical part, hospital information systems and programs, offered by companies for record keeping of batch parameters at radiodiagnostic workplaces, are mentioned. An integral part is also the legislation which governs the registration of batch parameters, not only in the Czech Republic, but also in the European Union. The practical part of the bachelor thesis provides a comparison of two radiodiagnostic sites. Furthermore, an analysis of data provided by the database of Radiodiagnostic Department of the University Hospital in Plzeň - Bory was conducted in the practical part of the thesis. Due to the increasing number of computer tomography, 20 most dose-intensive examinations were selected. What examination it was and what could cause such a high dose was examined.
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Measurement of patients´ personal doses in radiotherapy outside the central beam of ionizing radiation using the electronic personal dosimeter
CHYLÍKOVÁ, Renáta
The introductory part of the diploma thesis primarily focuses on the history of radiotherapy, i.e. what it emerged from and how it developed, as it is one of the most important fields in medicine, especially because thousands of people are irradiated every day due to different tumour and non-tumour diseases. Another reason why ionizing radiation is described is the fact that it is a necessary part of tumour disease irradiation. Ionizing radiation is also connected with radiation protection. This section presents a historical overview of radiation protection, as well as principles and quantities of this field. Furthermore, it focuses on Czech acts, decrees, and government regulations which define various measures governing this issue. Radiation protection forms the basis of patient, workplace, and personnel monitoring. All this is connected with the measurement and evaluation of received personal doses. This brings the thesis to the field of dosimetry, therefore various dosimeters used in practice are described. The aim of this diploma thesis is the measurement of patients? personal doses in head and neck irradiation using the electronic personal dosimeter at the radiotherapy centre of Nemocnice České Budějovice, a. s. The thesis is based on the question of whether irradiation doses that patients with head and neck tumours receive outside the primary radiation beam are negligible. The theoretical part of the thesis uses all available resources from both foreign and Czech literature. The practical part is based on numerical statistics, i.e. a quantitative method. The research was carried out at the radiotherapy centre of Nemocnice České Budějovice, a. s. Irradiation of patients with head and neck tumours was performed on a linear accelerator. Each patient had a mask to which an electronic personal dosimeter was attached during irradiation. Using this dosimeter, it was possible to measure doses received outside the central radiation beam. The measured values were then used to carry out assessment using formulas. Patients who undergo cancer treatment receive relatively high doses of radiation, so my main goal was to measure personal dose equivalents at the reference point. When comparing the percentage of the number of examinations with the web portal Epidemiology of Malignant Tumours in the Czech Republic, it was found that irradiation of the neck is more frequent than irradiation of the head. The total values of personal dose equivalents are relatively high in each patient, but because it is medical treatment, these values are not subject to radiation exposure limits. The comparison of the irradiated areas shows that irradiation of the neck has small values of personal dose equivalents to 1Gy compared to irradiation of the head.
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Dosimetric determination of radiation exposure of patients and personnel during diagnostic and interventional endovascular procedures at the DSA department of UVN, recovery plan for a potential extraordinary event
KRAHULA, Ondřej
Intervention radiology is a discipline that is achieving a great advancement due to its significant success in the treatment of various diseases. Also, it relates to the increase of the number of angiographic performances in the last years. The extension of radiological methods has increased the share of this discipline on the overall medical irradiation of the population. All angiographic performances are accompanied by certain risk related to the exposure of the patient and staff to the ionizing radiation. Several cases were reported where the surface doses were reaching the limits of deterministic effects of radiation in some types of examination. This study monitors three core criteria related to the radiation burden in the set of 141 patients, which have undertaken different endovascular interventions. These criteria are: the dose area product (DAP), surface dose, and effective dosage. The relevant criterion was the value of DAP, read from the DAP meter directly during the examination. Other data were calculated. On basis of these results, this study tries to determine the strenuousness of singular examinations from the point of the radiation burden. It is the understanding the principles of the influencing the patient{\crq}s burden of the radiation in angiographic examinations, what can help in reducing the dosages. The analysis of this study results can help to prevent the occurrence of abnormal events during the examination.
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The role of a radiation monitoring and a dosimetric provision in the first phase of a local radiation emergency
VOJTA, Jiří
In the last decades, the sources of ionizing radiation have been used more and in various branches of medicine, industries, agriculture and research. Like each human activity, the usage of the sources of ionizing radiation is also connected with possible occurrences of accidents and emergencies. Such events can then cause damage to a person health or the environment . The usage of sources of ionizing radiation belongs to those few human activities in the world, where a big attetion is paid not only to the development of appli-cations but also to their safety. However, despite all of it, it is not possible to eliminate the risk of accidents and emergencies. Recently, there has been some talk of possible misuses of the sources of ionizing radiation. Such extraordinary events place high on the first response forces. One of the first re-sponse forces is Fire Rescue Service of the Czech Republic, the forces of which are lo-cated over the Cezch Republic. This thesis shall provide these forces with such infor-mation that they should be able, along with the authorities responsible for the radiation protection, to evaluate the situation and minimise effects on health, lives and environ-ment in the event of radiation extraordinary event. The purpose of this thesis is to solve local extraordinary radiation events (such as acci-dents during the transport of the sources of ionizing radiation, discovery of an unknown radiator). It does not deal with nuclear emergencies and accidents of other equipment, where the scope of the event and its consequences are of nation-wide importance. The first part of the thesis includes basic terms of the ionizing radiation and radiation pro-tection. The other part is focused on the radiation research, monitoring, response system and dosimetry devices. This part also includes materials for trainings and drills focusing on early identification of raiation hazards of an extraordinary event.
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Confrontation of radiation dose of professional in nuclear medicine department in Hradec Králové before and after installation PET/CT, possibilities of monitoring
JANSOVÁ, Martina
This Bachelor Thesis deals with the radiation load of Nuclear Medicine employees of University Hospital Hradec Králové before and after the introduction of PET/CT examinations. Compared with usual examinations with gamma emitters and therapy with open beta emitters, the PET/CT examination method uses positron emitters and is carried out at the Department of Nuclear Medicine of University Hospital Hradec Králové (DNM UHHK). The use of positron emitters leads to increased demand in respect of radiation protection and work organisation. I made an evaluation of doses from personal dosimetry from 2004 until 2008 prior to the introduction of the PET/CT examination methodology; and year 2009 is subsequently assessed in respect of the situation after the introduction of PET/CT examinations. The results of doses are provided in tables. Film dosimeters and thermoluminescence (TL) ring dosimeters had been used for personal dosimetry until 2008. Digital dosimeters have been also used for personal dosimetry since 2009, and they are further included in the comparison of the received radiation doses of employees. The results were used for an evaluation of optimisation of radiation protection at the DNM UHHK.
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