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The Cesium-137 content in wild game in Šumava.
VENČOVSKÁ, Petra
Our territory was the artificial radionuclide cesium-137 (hereafter 137Cs) contaminated by radioactive contamination during nuclear testing in the atmosphere and to the largest nuclear accident occurring in Chernobyl. Contamination of the environment and its components 137Cs is still being monitored due to the long half-life of this radionuclide. The stated goal of the work is to compare the mass activity of 137Cs in the forest species from the Šumava region. This also results in the research question as to whether there is a difference in 137Cs in the mass of different animal species living in forests in the Šumava region. According to the availability of samples, the administrative districts of Vimperk and Horní Planá were selected. From these localities, there are also 14 measured samples of fur animals, which were provided for this research. Consequently, the content of 137Cs was determined by gamma semiconductor spectrometry, which, besides mentioned 137Cs, was also used for comparison with potassium-40 (hereinafter only 40K), which is the most widely used natural radionuclide. The measurement results also show that higher concentrations of 137Cs were in samples from the Vimperk region, and also that higher mass activity of 137Cs was measured in herbivores. The highest value of 40K was measured in both herbivores and omnivores. Effective dose ranges were calculated from the results obtained to express the level of contamination that would occur in the case of the consumption of contaminated meat. Calculated values of effective dose ranges due to internal contamination as well as other sources of radioactivity are not significant and their effect on the health of our population is negligible.
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Calculation of efficient dose rtg diagnostic irradiation
Bažantová, Lucie ; Drastich, Aleš (referee) ; Rozman, Jiří (advisor)
This bachelor thesis deals primarily with the theory of ionizing radiation and its interaction with matter. It deals particularly with x-radiation and the methods of its use in medicine. The thesis contains a description of the origin of the x-ray image and a description of the techniques of radiography and skiascopy. A list of quantities and units used in radiation physics and in radiation protection has been set out, with regard to assessing the risk involved in the interaction of x-radiation with an organism. In particular, the effective dose and the methods of evaluating this during medical irradiation have been set out. The main parts of the work are an overview of the software environment used in radiation physics and an example of the calculation of an effective dose for a concrete radiographic examination together with a detailed description of the method of calculation. At the end of the thesis there is a table of calculated values and an evaluation of them.
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The Radiation protection of Patients and staff in Nuclear Medicine.
DAŇOVÁ, Kristína
Open radioactive sources are used at the department of nuclear medicine for diagnoses and therapy, as well as for research purposes. Ionizing radiation is applied in all cases. Since a negative impact of this radiation has been depicted, it is necessary to systematically reduce the radiation on people, and protect the environment. The title of this bachelor thesis is: "Radiation protection of staff and operatives at the Department of Nuclear Medicine". This thesis is devided into several parts. The beginning of the theoretical part focuses on history of origins of radiation protection and institutions which deal with it. Further, nuclear medicine as such, its equipment, and structure of the department in general is described. The conclusion then introduces the DNM in the town of České Budějovice. Ionizing radiation and its biological effects on organisms were defined, as well as quantities and units which characterize it. A considerable part of this work focuses on principles of radiation protection, monitoring of the staff, workplace and releases. This work also deals with dosimetry and lists types of used dosimeters. It assesses the risks of outer and inner radiation. The aim of this thesis was to analyse laws and regulations which are connected to radiation protection and identify its effective application for staff and patiens of the DNM in České Budějovice. Another aim was to examine the radiation protection of patients at the Department of Nuclear Medicine, as well as the radiation protection of patients and staff at the inpatient ward. The research question was: "Is the radiation protection of patients and staff at the Department of Nuclear Medicine in hospital in the town of České Budějovice sufficiently optimized?" The method of research was assembling and recording materials of nuclear medicine in České Budějovice, compare doses of thermoluminescent dosimeters of the staff in outpatient and inpatient wards, and compare doses of finger and whole-body thermoluminescent dosimeters. The practical part provides detail information, charts and graphs of effective and equivalent doses of staff of outpatient and inpatient wards of the DNM in the town of České Budějovice between years 2009 and 2013. The outpatient ward comprises of fifteen employees. The inpatient ward of three nurses and one hospital attendant. These were observed in details for effective dose equivalents Hp(10) during each individual month for the period of five years. Results from the personal whole-body and finger dosimeters have been used for the analysis. The values of equivalent doses of HT from finger TLD are recorded for two of the employees. The data for the hospital in the town of České Budějovice was assessed by CSOD Ltd. In Prague, a company which has been providing dosimetric calculations in the Czech Republic for over tweny years. This data was compared with limits for radiation workers, which are regulated by State Office for Nuclear Safety no.389/2012 Sb., from November 16th, 2012, which changes the public notice of State Office for Nuclear Safety no.307/2002 Sb., about radiation protection as amended by public notice no.499/2005 Sb. The outcomes of the thesis have remitted a very high level of radiation protection and well-established measures in the protection of staff and patients against negative effects of ionizing radiation in the hospital of the town of České Budějovice. The thesis is then enhanced by a discussion, which reflects the outcomes compared with professional findings summarised in the theoretical part. The answer to the research quesion is: "Yes, radiation protection of the staff and patients at the Department of Nuclear Medicine in the hospital of the town of České Budějovice is sufficiently optimized." This bachelor thesis can be used as a study material for students of the field of study Radiology Assistant.
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Radiographers role in biliary interventions.
MINÁŘOVÁ, Olga
Radiological assistance during non-vascular interventions on the biliary tract. The presented Bachelor's thesis includes information from the practical course in an interventional facility of the Department of Imaging Techniques, Motol University Hospital, while assisting during PTC and PTD procedures. In the Czech Republic, these procedures are most frequently performed in patients with inoperable malignant stenosis of the biliary tract where the method of first choice, the endoscopic approach (ERCP), is not possible. I would like to emphasise the importance of knowledge and use of the state-of-the-art materials and technologies that facilitate our work and ensure a non-complicated course of examination for the patient. By comparing the radiation burden in assisted and non-assisted procedures, I would like to demonstrate that the overall final effective dose during assisted procedures is lower than during the procedures performed by the surgeon alone. Data obtained from two groups of thirty patients with an identical diagnosis, who received treatment with or without assistance, was statistically compared and plotted in a graph. In the selected sample of sixty patients in whom this procedure was indicated, I used the parameters obtained to perform a final calculation of the effective dose. The results confirmed the hypothesis that the assisted procedures require less time than the unassisted procedures, and that the effective doses are lower and not dependent on the BMI value. We should also take into account the factors that might influence the overall course of the examination, such as for example the patient?s overall health and his/her diagnosis. The length of the procedure depends on the experience, length of practice and skills of the radiologist. The radiology assistant, as a practicing specialist, plays an important role in the entire interventional team. PTC/PTD is a method which has a low burden for the patients, a low occurrence of complications, and is life-saving in some cases. The possibility of reducing the burden on the patient and the personnel can be achieved by having a sufficient number of qualified staff at the interventional radiology facilities. The symbiosis of the entire examination team is a guarantee that the procedures will be performed in the best possible way and in the shortest possible time, with a low radiation burden for the patient.
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Nuclear tests and their implications for public health and environmental quality
FABIÁN, Lubomír
The aim of this thesis is to give an overview of past nuclear testing and draw some conclusions regarding its potential implications on public health. The introduction presents all kinds of nuclear tests, the history of nuclear testing with respect to particular countries, provides the description of the kinds of ionizing radiation and protection against it as well as the biological effects of ionizing radiation on tissue. There is a part devoted to international treaties in this field ? The Partial Nuclear Test Ban Treaty, The Threshold Test Ban Treaty and The Comprehensive Nuclear Test Ban Treaty. The summary of the number, the yield and the geographical distribution of the past atmospheric nuclear tests follows. There is an explanation of the global fallout mechanism of the radionuclides released, the estimates of emitted doses and the relationship between these doses and their probability of inducing cancer in the human body. The objective of this work is to make an assessment of the contribution of doses originating from nuclear testing to total population doses (irradiation) and subsequently quantify health implications for the population. The method of achieving this is based on calculating theoretical estimation of cancer incidence from known effective doses commitments and in comparison with those real incidences raised by all the different sources and reasons in world areas chosen, derived from the statistical data gathered from scientific studies and publications of international organizations involved. The outcome of this work is the confirmation of the first hypothesis that nuclear testing has statistic impact on enhancing the frequency of cancer disorders on the world population; however this is relatively small with respect to the other sources of radiation and a rate of naturally spontaneous (non-radiation-induced) cancer occurrence. Also the second hypothesis that underground nuclear tests have significantly smaller influence on public health and environment quality than the other kinds of nuclear tests is acknowledged.
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Renal colic - Intravenous excretory urography versus Native examination of uropoetic´s system on spiral CT
CHALUPOVÁ, Dana
Renal colic - intravenous excretion urography versus native examination of the uropoietic system using a spiral CT scan This thesis presents a comparison of two imaging techniques that are most frequently indicated for diagnosis of renal colic. These are intravenous excretion urography and native examination of the abdomen and pelvis using a spiral CT scan. By comparing the following aspects, I would like to contribute to the complete elimination of the indication of intravenous excretion urography and replace it with spiral CT scanning. The objective of this thesis is to demonstrate that native examination of the abdomen and pelvis using a spiral CT scan is more beneficial and more suitable both for the diagnosis and for the patient. Within the thesis, I also compare the aspects of radiation burden, time and financial requirements and last but not least the overall burden on the patient over the course of the examination. The comparison was performed by calculating a typical effective dose in a sample of fifty patients examined by intravenous excretion urography and fifty patients examined by spiral CT scan. The results are shown in graph format. These results did not confirm the hypothesis that the radiation burden is lower in spiral CT scanning. The doses determined in my thesis are up to three times higher in the CT scan. In financial terms, both imaging techniques have been evaluated as almost comparable and the price of the examination should not influence selection of the method. Spiral CT scanning is much more beneficial when comparing the time needed for performance of the two techniques. The results pertaining to the radiation burden for patients during spiral CT scanning suggest how important the radiology assistant?s ability is in influencing the size of the effective dose by the proper selection and inspection of the exposure parameters when selecting the examination protocol. This statement is further strengthened when comparing the results of this work with those of foreign studies, where the radiation burden on patients examined by spiral CT scanning was one to four times lower than my results of effective doses. The effective doses obtained were close to the effective doses determined during intravenous excretion urography. The objective of this Bachelor's thesis is to outline the possibilities for reducing the radiation burden on patients examined by spiral CT scan.
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Comparsion of the Classical Catheter Angiography and CTAG; the Benefits and Deficiencies of Both Methods, including Radiation Load
BLAHNÍKOVÁ, Kateřina
The title of this Bachelor{\crq}s Thesis is Comparison of the Classical Catheter Angiography and CTAG; the Benefits and Deficiencies of Both Methods, including Radiation Load. I carried out the comparison in the area of positives and negatives of these methods, related risks and mainly in the area of patient radiation load, which is the subject of the research. The first part deals with brief characteristics of anatomy and vascular system physiology, introduction to both methods, including a chapter dedicated to contrast media and a brief description of radiation protection. When defining the benefits, deficiencies and potential risks I came to a conclusion that there cannot be unequivocally recommended just one method, for both methods provide different advantages and therefore the final decision must be made by the doctor. To assess patient radiation load I used data from 1 July 2008 to 30 June 2009 of patients, who underwent an examination of brain blood vessels in České Budějovice Hospital. To carry out the comparison it was necessary to convert the results into an effective dose. In case of CTAG I made the calculation using a literature available coefficient. For classical catheter angiography I used the version 1.5 PCXMC program. Due to a lack of data (e.g. the angle of a primary beam incidence) the calculation made was only approximate. To find out the occurred error I used data of patients examined from 8 March to 23 March 2010. The consequent statistical data assessment showed that the CTAG method represents bigger radiation exposure for human organism than classical catheter angiography, which proved the hypothesis. In connection with the lack of data regarding the carried out classical catheter angiography I would consider keeping a larger amount of data beneficial for potential calculation of an effective dose. All data required for an accurate calculation of an effective dose can currently be obtained only during the examination.
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Monitoring and comparison of radiation dose of patient and physician during examination of brain arteries with single plane (conventional) digital subtraction angiography (DSA) and biplane DSA
SLAVÍKOVÁ, Jana
In experimental part I deal with measurement of radiation dose of the staff and patients in angiography examination of brain arteries.I compare the measurements with the use of single plane and biplane DSA and radiation dose of patients. The measurement was carried out with Siemens Axiom Artis Biplane machines at radiodiagnostic department in"Na Homolce"hospital. For the calculation of dose the programme Effdose version was chosen. I also compare measurement in physicians during angiography examination at radiodiagnostic department in České Budějovice hospital and in {\clqq}Na Homolce" hospital in Prague. For these purposes electronic personal dosimeters EPD Mk2 ( Siemens firm) were used. All results were worked out into graphic charts for better clarity.In the end of my work the proposals and measures, how to reduce radiation dose which is necessary in these angiography examinations, are described.
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Diagnosis and endovascular therapy of cerebral aneurysm
SVAČINA, Igor
Summary Diagnosis and endovascular therapy of cerebral aneurysm The first part of this bachelor work is aimed at the key examination methods such as CT, MR, DSA etc., leading to the determination of diagnosis of subarachnoidal haemorrhage caused by brain aneurysms. It describes both etiology, pathogenesis, incidence of brain aneurysms and also anatomy and physiology of wessel wall and brain wessel supply {--} circle of Willisi. It explicates parametres of adjusting examination modalities for each individual procedure. Next part deals with the endovascular therapy of cerebral aneurysms. It is engaged in the embolization by coils. Detailed information was acquired from special medical literature and also by the observation of routine working procedures in radiology departments and interventional radiology departments in hospitals during scholarships. The target of the bachelors work is also to assess the role of radiographers in the process of determination of subarachnoidal haemorrhage (SAH), which is caused by brain aneurysms, and also during the endovascular therapy of brain aneurysms. The assumption, that radiographers are really necessary and important during examination and that they are useful members of operating team, came true. The further part is focused on the detection and comparison of levels of the patient{\crq}s radiation stress during the endovascular therapy of brain aneurysms. It compares total skiascopy times of these interventions and searches for differences in the amount of applied iodine contrastive solutions. The compared data come from two angio units, Siemens Multistar (2000) and new Siemens Axiom Artis (2006), that are used in the department of interventional radiology in Homolka hospital. The data of 26 patients necessary for calculation of the effective dose were obtained from the operating diaries of both angio units. Effective and organ doses were subsequently calculated by the software programme called Effdose. It was found that effective doses from both angio units are relatively low. The entrance surface doses and organ doses (thyroid, eye lens etc.) cannot cause any skin injuries and any deterministic effects. Radiation stress in Siemens Axiom Artis is almost half lower than in Siemens Multistar. The hypothesis that effective doses in the new angio unit Axiom will be lower proved true. Differences between total skiascopy times and amounts of applied contrastive solutions were slight. The hypothesis that total skiascopy times and amounts of applied iodine contrastive solutions in the new angio unit Axiom will be lower did not prove true.
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