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Model of dynamic contrast CT data for verification of registration algorithms
Kupková, Karolína ; Harabiš, Vratislav (referee) ; Walek, Petr (advisor)
This work is focused on the description of the dynamic contrast-enhanced CT examination and its contribution in the pneumooncology. It includes a program for creating a two-dimensional model of the scan from the thorax and for the perfuse examination simulation using the time-density curve. Real CT data are simulated more authentic using rigid geometric transformations and noise. The model will be used for the validation of registration algorithms that is used to suppress the spatial deformation generated by patient motions during the long time examination.
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Model of dynamic contrast CT data for verification of registration algorithms
Kupková, Karolína ; Harabiš, Vratislav (referee) ; Walek, Petr (advisor)
This work is focused on the description of the dynamic contrast-enhanced CT examination and its contribution in the pneumooncology. It includes a program for creating a two-dimensional model of the scan from the thorax and for the perfuse examination simulation using the time-density curve. Real CT data are simulated more authentic using rigid geometric transformations and noise. The model will be used for the validation of registration algorithms that is used to suppress the spatial deformation generated by patient motions during the long time examination.
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Preparation of patient prior to application intravenous of contrast medium in relation to the prevention of renal failure
PUCHOLTOVÁ, Lenka
The topic of the bachelor thesis is the patient preparation prior to intravenous contrast in relation to the prevention of renal failure. The theoretical part deals with the anatomy and physiology of the kidney, provides information about the contrast media of their properties, uses and side effects. At the end of the theoretical part describes the contrast medium-induced nephropathy. In the practical part I focused on finding out what is the incidence of contrast nephropathy in individuals with normal creatinine levels depending on the amount of contrast agent and the preparation of the patient. I obtained the data from the hospital information system Masaryk Hospital Townsville. The database contained a set of hospitalized patients in the years 2009 - 2011, which were performed CT examinations associated with the administration of iodinated contrast media. Part of the personal data of patients, the tests used, the type and amount of contrast agent and creatinine values. Since creatinine values were available for all patients, the final database was created from 938 patients with baseline of normal creatinine levels before the examination for which they may be level <than 130 mmol/l. The final group of patients was analyzed according to the defined aims and statistically processed. Hypothesis of this study: the incidence of contrast nephropathy in individuals with normal creatinine levels depending on the amount of contrast agent as a suitable preparation of patients prior to administration of iodinated contrast material does not exceed 10% - was confirmed. In the investigated group of patients was proved preventive effect of patient preparation before the test - hydration. A higher incidence of CN was observed in the group of patients whose preparation has taken place.
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Rotational angiography
JAŠAROVÁ, Eva
Digital Subtraction Angiography (DSA) is a special X-ray examination of the blood vessel system. Despite the development of other visual techniques it has not lost its importance so far. In the 1960s and 1970s it developed itself into the most detailed method of visualization of the blood-vessel system. DSA requires much more expensive device and equipment with tools than only ten years ago. The price is equal to the quality and amount of information. DSA further remains the invasive method. One or two-projection system for acquiring the complete picture of blood vessels is the most used technique of record in angiography. Common methodologies require two applications of the contrast medium for the same part of the body. Rotation angiography is a special modern technique for three-dimensional visualization of arteries. It is mainly used for visualization of neck or brain arteries. Its principle is in the application of the contrast medium into the artery, when the examined area is X-rayed and C-arm is continuously turned by 180°. The final angiography can be assessed that we turn the picture step by step. If we display the same area once more without the application of the contrast medium, we get a mask for DSA and both sequences we can subtract. Only one artery is displayed as well as during classic DSA.
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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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The specific approach to diagnostic imaging methods in patients with diabetes mellitus
KLIMEŠOVÁ, Jitka
Diabetes mellitus occurs as a result of absolute or relative lack of insulin. It is a chronic disease which can lead to damage of other systems and organs. Number of patients with diabetes mellitus undergoing medical examinations or interventional therapy by the diagnostic imaging methods has been increasing. It brings higher demand on technical parameters of the methods and more exact work of medical staff. Examinations connected with administering contrast media can cause many complications to these patients and the routine examination can be changed into the dangerous one. The position of a radiological assistant has become more responsible. The aim of this Bachelor´s work was to outline diagnostic options while examining patients with diabetes mellitus and consider using diagnostic imaging methods as the administration of diagnostic contrast media can be risky for the patients. Twenty six per cent (236 patients) out of 918 patients with diabetes mellitus type 1 or type 2 who visited the Diabetological Centre and the Department of Radiology of the Hospital in České Budějovice were examined by some of the diagnostic imaging methods. Adult diabetic patients underwent these radiological examinations: 188 skiagraphies of lungs, 119 skiagraphies of skeletons and 18 examinations under skiascopic control. Forty-four patients were examined by the sonography, 10 by the mammography, 110 by the computed tomography, 9 by the magnetic resonance and 10 patients by the angiography. Most diabetic patients were examined by common skiagraphy of arms and legs, sculls, vertebral columns due to injuries, fractures and degenerative changes. Skiagraphies of heart and lungs were indicated before and after operations or they preceded applying an insulin pump. The other numerous group was made up by patients with tumours. They were mostly examined by computed tomography. Fifty-seven patients developed complications caused by diabetes. The examinations of carotid arteries, cerebral arteries, arteries and varicose veins in the legs were carried out by sonography, computed tomography and magnetic resonance. In six cases diagnostic angiography was followed by percutaneous transluminal angioplasty. The use of contrast media in 64 patients was also considered. In all cases non-ionic contrast media of low or medium osmolarity in the volume of 80 {--} 125 ml were used. The findings compared with those presented in literature proved the hypothesis that radiological assistant work requires a specific approach towards the diabetic patients.
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The Imaging in Cases of Obesity and the Metabolic Syndrome
DUŠKOVÁ, Radka
This thesis deals with imaging in cases of obesity and the metabolic syndrome. It mainly focuses on the diagnostic imaging using imaging modalities, such as skiagraphy,skiascopy, ultrasonography, computer telegraphy and magnetic resonance. The objective of this thesis was to determine the characteristic and specific qualities of various diagnostic procedures of a radiological assistant when imaging patients suffering from obesity and the metabolic syndrome, especially when a contrast medium is used during the treatment, and then to compare the diagnostic possibilities of imaging when different imaging modalities are used. The theoretical part describes obesity and the metabolic syndrome, with the special focus being done on their possible extent and resulting complications. Theimaging modalities do not image obesity and the metabolic syndrome as such, but deal with the diagnostics and the treatment of various illnesses caused by metabolic dysfunctions. The issue of diagnostic imaging is complicated by the differences in methods caused by the use or non-use of ionizing radiation. The increased risk of complications during the treatment of patients suffering from obesity and the metabolic syndrome can be caused by the use of a contrast medium, which is mostly used in diagnostic imaging and it is also sometimes used in therapeutic imaging, such the invasive treatment of the cardiovascular system. For this reason, this issue has also been dealt with in this thesis. The practical part contains an evaluation and a comparison of 100 questionnaires that have been filled in by randomly selected patients of the Radiological Department.The questionnaires were anonymous and those questions were created so as to determine the prevalence of obesity in the investigated sample, which would then provide information about the possible complications that can occur during an examination which have been caused by obesity and the metabolic syndrome. After completion of the questionnaire by these patients, I also participated in their examination and verified my presupposed hypothesis in practice. The results of the questionnaire research and the participation in the examination of respondents confirmed my hypothesis that imaging in obesity and the metabolic syndrome requires a special approach, especially when contrast mediums are used during the treatment. Attention has to be paid not only to the technical modifications of procedures in individual imaging modalities, but also to the specifications connected with organ polymorbidity and the related complicating pathological conditions. Since the prevalence of obesity and the metabolic syndrome is increasing, it is very probable that we will meet patients suffering from this type of illness increasingly more often at the Radiological Department. This is another reason why the specificities of imaging patients suffering from these illnesses should be gradually implemented into regular radiological imaging procedures.
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Disturbing artifacts of radiodiagnostic modalities
ŠEDA, Miroslav
This work gives information on machines used for diagnostic imaging aimed to disturbing scan artefacts of chosen device (CT, MR, USG). Radiology assistant work still more depends on technique which helps in examination. The machines used for clients´ examination are thanks to IT development still more complicated. They allow high-quality and precious images, give more possibilities of treatment ways, save the client. Operating this technique is the domain of radiology assistants. Development without restrain leads to period when operating staff will work more independently. It is necessary for the radiology assistant to manage all steps in examinations which are undergone. He has to keep radiation protection and the quality of the image result as well. The result of most diagnostic examination in radiology department is image information. Image results can be from various reasons changed or deformed in comparison with the reality. Such distorted images can lead up to mistaken or late diagnosis by the physician. Radiology assistant is the first specialist who must be able to judge whether the examination has been done correctly or to warn the physician of possible variation or image deformation. Moderation or suppression of artefacts in image results in examination is easy in some cases. Then it is enough to explain the process of examination to the client and to emphasize how important is to cooperate with the staff. In some cases is technically impossible to impact the manifestation of artefacts as it results from the principle of examination method, or because of high financial costs unbearable for the health institute. In my work I aimed to image artefacts of machines (CT, MR, USG) which can be met in common clinical practice. I tried to document these image artefacts in common running. Part of my work is to describe the causes of artefacts appearance and the way how to avoid or remove their manifestation.
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Influence of the contrast medium iodine concentration on quality of the CT examination
RANŠOVÁ, Pavlína
Our work focused on determining absolute and relative density of various contrast agents in relation to iodine contents using in vitro and in vivo methods. It was documented that the relative density of contrast agents increases with the decreasing contents of iodine, i.e. density absolute values vary inversely as iodine content in these substances. Four various agents, bearing commercial names Visipaque 270, Visipaque 320, Ultravist 370 and Iomeron 400, in their original glass packing were used for our in vitro measurements. The measurements were carried out using CT equipment Emotion Duo (Siemens, Forchheim, Germany). Individual packing of the contrast agents were scanned by means of a standard protocol and under standard conditions. The obtained data were entered into tables. A retrospectively selected array of patients with standard scan of their stomachs was used for our in vivo measurements with a defined standard protocol using the same CT equipment and pressure injector CT 9000 Advantage (Liebel-Flarsheim, Mallinckrodt, the U.S.A.). The following data from 258 patients were recorded: age, sex, blood density after administering contrast agent in vitro on the level of diaphragm hiatus and on the bifurcation level, AP dimension of the patients on the hiatus level. Mean densities of the individual kinds of contrast agents were compared and a good correlation with the in vitro measurements was found out. The measured values were then analysed. The interdependence was studied in the measured densities and age, density changes measured on the hiatus level and on the bifurcation level for the individual contrast agents. The interdependence of the blood density on the AP dimension of the patients was also studied due to its practical use and it was documented that there is a good correlation of the decreasing density with the AP dimension as a simple parameter used instead of finding out patients{\crq} weights.
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