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Segmentation of Ultrasound Images Based on Active Contours for Image Registration
Hesko, B.
This paper describes the implementation of the segmentation method applied on ultrasound images, which is based on active contour models. The physical meaning of these models is represented by energy minimalisation of initially defined curve. Energy could be written as a weighted sum of internal and external energy. Internal energy is strictly dependent on the properties of the curve and external energy si represented by a feature extracted from the image. First and second derivative of the curve is used to calculate internal energy and Laplacian of the image as a feature to calculate external energy. Total energy is minimised by iteratively moving points of the curve. Achieved results and persistent problems are evaluated, suggesting the way the future work should lead.
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The role of radiology in children hip screening in Pelhřimov Hospital, c. o.
CHADIMOVÁ, Jana
The topic of this thesis is to compare the use of imaging methods in children hip screening and to find out the presence of developmental dysplasia of the hip (DDH) in Pelhřimov Hospital. DDH is the most common musculoskeletal developmental defect which affects approximately 5% of newborns. It includes an impaired development of acetabulum, femoral head, poor centering into the acetabulum or disproportionate extent of joint movement. DDH is being formed by interaction of genetic factors and external causes. If DDH occurs in the family, the risk neonate increases significantly. The most serious stage of this defect is hip dislocation, but we often meet a lighter form of this defect, which is called shallow acetabulum. The Czech Republic established a system of consecutive check-ups of neonates and infants. It was created on the base of Methodological Sheet of the Ministry of Health from 1996. These examinations are carried out in three stages. During these examinations, ultrasound plays a very important role. The most common method, also used in Pelhřimov Hospital, is the method of Austrian professor Graf. This method evaluates findings and classifies them into groups. After the first year of age, when ossification of structures is nearly completed, the findings cannot be evaluated by this method. X-ray examination is applied in case of diagnostic uncertainties - especially when planning subsequent treatment in children with DDH diagnosis. Imaging methods are applied to determine anatomical reposition obstacles after an unsuccessful primary reposition. We can use ultrasound, magnetic resonance, but we prefer arthrography. Arthrography is more invasive method, but unlike the others, it has got an important advantage: it can also be a therapeutic method. The theoretical part deals with anatomy, development and growth of the hip joint. I also present etiology and history of this developmental defect. The following part deals with a description of the system of clinical check-ups and diagnostics of DDH. Another part of the theoretical work is devoted to individual imaging modalities - ultrasound, X-ray, magnetic resonance and arthrography. Imaging modalities are a very specific part of radiodiagnostic. Paediatric patients are not small adults, their imaging should be restricted to a minimum and it has got its own specifics. The examination must be performed quickly and accurately, in order not to have to be repeated. Options of therapy varies according to the severity of the hip joint. A small damage of the hip joint is solved by a conservative way using various abduction tools like abduction package, Frejk duvet or Pavlík calipers. More serious cases need to be solved by hospitalization, using distraction therapy or surgery. The aim of this work was to analyze the number of paediatric patients, to find out what kind of imaging methods were indicated and performed and to compare the presence of congenital defect of the hip according to sex within Pelhřimov Hospital. The hypothesis of this thesis was formulated as follows: In paediatric hip screening examination in Pelhřimov Hospital presence of congenital defect of the hip is higher in girls than in boys. The purpose of this thesis was to create a comprehensive text dealing with the use of imaging methods in detecting developmental defects of paediatric hip. The theoretical part of this work may serve as information material for professionals and the results can be used as statistical material.
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Radiographer role in non-vascular intervention procedures and their frequency at Imaging clinic of Faculty Hospital Motol in years 2008 - 2013.
BOROVCOVÁ, Veronika
This bachelor thesis focuses on non-vascular interventions, which are carried out at the Imaging clinic of Faculty Hospital Motol. The area of interest was fixed to the adult part of this clinic. The most frequently performed interventions were described and for aech of these examinations was depicted the role of radiographer (patient preparation, sterila table and instrumentation preparation) and it´s operating procedures. The other part of the thesis pays atention to statistical analysis of the frequency of individual most often led examinations. The statistical overview was done by using tables but also graphs. The examinations are devided according to their modalities based on where they were ran. This division was left for statistical part, as well. The period of time, which was trailed in this thesis makes 6 years, since 2008 to 2013. The obtained data displays the individual frequency of interventions and covers complete overview in mentioned issue.
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Special access of the radiology assistant to interventional procedures in diagnostics of oncological patients
CANDROVÁ, Daniela
In my work I deal with the peculiarities in approach of a radiology assistant to interventions in diagnostics of oncological patients. Biopsy has a special importance in diagnostics of neoplasm. It is essential for histological and cytological diagnostics. The aim of this work was to find out the incidence of bioptic interventions on oncological patients during one year at radiology department at České Budějovice hospital plc, and to compare the advantages and disadvantages of used modalities. The work proceeds from the presumption that the number of interventions carried out under the sight control without the use of ionizing radiation methods is growing. In the theoretical part of my work appear descriptions of bioptic methods of intervention radiology regarding oncology and its methods, biopsies, screening methods used at biopsy (ultrasound controlled biopsy, computer tomography controlled biopsy, magnetic resonance controlled biopsy, skiascopic controlled biopsy), instrumentarium, especially the needles used for tissue extraction (puncture and bioptic needles), characteristics of oncological patients, the principle of tumour disease, carcinogenesis, oncologically changed tissue, and basic diagnostics of oncology disease. The practical part reveals the number of biopsies performed in 2012 at České Budějovice hospital plc, under computer tomography, ultrasound and mammography machine control, and the number of other interventions on oncological patients, namely localization of impalpable breast lesion, percutaneous drainage of the urinary tract under skiascopic control. Standard methods regarding these interventions and biopsies are described focusing on the advantages and disadvantages of their use for different organs in the body. I also described radiology assistant?s work and created photo documentation of given interventions. In 2012, 96 biopsies were performed under any of the mentioned diagnostic screening methods at radiology department of České Budějovice hospital. They represent 0,06% of the total of 171 466 diagnostic interventions at this department in the respective year. At the same time they represent 3,4% of the total of 2844 interventions of the ČB radiodiagnostic department of that period. From the whole number of 96 biopsies, 79% were performed on oncological patients. No biopsies were performed under magnetic resonance or skiascopic- skiagraphic control. Since the formation of a tumour is supposed to be the main somatic risk which an individual after a low intensity radiation faces, I supposed that the number of bioptic samples taken under sight control without the use of non ionizing radiation is rising, which significantly contributes to radiation protection. It is not univocally assigned which screening method is the best for biopsy. Usually we chose the biopsy that can screen best the site in different organs and that allows the safest, the fastest and the economically most convenient procedure. The chosen method should allow the doctor chose the site for sample extraction. The choice also depends on the habits and the technical equipment of given hospital. In view of the fact that according to this work computer tomography is the most commonly used method for bioptic extractions, and under magnetic resonance control no biopsies are performed, the prestige and importance of a radiology assistant grows up, because their presence at modalities using ionizing radiation is commonly indispensable. The hypothesis of my work has not been proved. Concrete results do not support the operative hypothesis of y work. However, I can recommend concessive long-term type and multicentrically elaborated sample studies. I would be grateful if this work provided an information base for radiology assistants´ training and for interventions in the diagnostics of oncologically ill people.
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Contrast medium in the ultrasonography
BLECHA, Dalibor
Ultrasound method belongs to the most extended and easily available modern investigative diagnostic techniques. It is the step number one in the investigative diagnostic algorithm. The beginning of this method dates back to the early fifties of the twentieth century. With respect to the fact that the usage of ultrasound contrast agents and the development of an {\clqq}optimal`` contrast agent has not finished, I refer to some limitations and obstacles. Although this process is similar for all contrast agents in all fields of modern imaging methods. Implementing new findings and observations into a clinical practice is connected with lots of difficulties and obstacles that restrain their success. In the same way as the contrast agents found their application in various modern imaging techniques, the ultrasound contrast agents are also expected to find their place in the ultrasonography. This fact acknowledges my hypothesis and points at application of ultrasound method as the first choice.
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Prenatal diagnosis by imaging methods
VLČEK, Martin
The bachelor degree thesis focuses on imaging methods in prenatal diagnostics. The theoretical part informs the readers about the current situation in this field, including invasive and noninvasive examination methods. The theoretical part is concluded with a chapter on prenatal detection of heart disease by means of screening examination of pregnant women. The objective of the thesis was to highlight the activities of a radiological assistant, to describe his/her activities during the use of various modalities and possibilities in diagnostics of congenital heart diseases, both prenatally and perinatally. One hypothesis was formulated, concerning the activity of a radiological assistant in diagnostics of congenital heart diseases during the prenatal period. The quantitative research was designed based on the number of examined fetuses and newborns in the teaching hospital (Fakultní nemocnice) in Motol and in the Center of Medical Genetics (Centrum lékařské genetiky s.r.o.) in České Budějovice in the course of 1 year. In 59 fetuses examined with magnetic resonance the following 3 congenital heart diseases were detected most frequently: 7 cases of agenesis of corpus callosum, 6 cases of ventriculomegalia and 7 cases of congenital cystic adenomatoid lung malformation. None of the examined mothers was diagnosed with placenta defects or pathological changes on the fetus heart. The formulated hypothesis has been confirmed. At present, congenital heart diseases are not routinely prenatally examined by means of magnetic resonance due to the too robust technology and insufficient quality of the imaging. The prominent role is still being played by ultrasonic examinations performed by gynecologists and obstetricians. The thesis and the research results may be used by cardiologists, gynecologists, obstetricians, as well as radiologists.
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Doppler measurement of vessel parameters
NÁTHEROVÁ, Markéta
Ultrasound investigation is the most common and most readily available current advanced diagnostic method. Ultrasound can be used to track and image moving structures such as cardiac valves or flowing blood {--} these methods are based on the so-called Doppler phenomenon. Using the Doppler phenomenon, it is possible to determine the velocity and direction of movement of the measured object. The objective of this work was to track the changes of vascular flow and pulse rate depending on the degree of tolerance of exercise attained by the test persons, the stress (load) and ambient temperature changes. For this purpose, 2 groups were defined where the first group consisted of individuals adapted to the stress, while the members of the second group were untrained. To measure the vascular parameters we used a Doppler meter, HiDop 300. The LCD display of the instrument, or alternatively the monitor of a connected computer, provide images of the measured spectral Doppler curve as well as its parameters (heart rate HR, resistance index RI, pulsatility index PI, systolic/diastolic ratio, mean frequency). The work is concerned with the impact of physical load and cold-related stress on the circulatory system in the vessels. The haemodynamics of the vascular system depends on the type and intensity of the load. The formulation of results of the work, however, must account for a number of internal factors (age, sex, health {\dots}) and external factors (ambient temperature, air flow {\dots}) that are themselves associated with various changes in the circulatory system. For example, reduction of peripheral vascular contractility in the elderly, disruption of vascular wall elasticity by depositing fatty substances or increased heart rate due to the stress stimulus. The main advantage of a Doppler instrument and all ultrasound methods is to be seen in the fact that it is a non-invasive method, and has no adverse effects on the investigated person, such as the effects associated with roentgen radiation, provided, however, that appropriate intensity of ultrasound radiation has been chosen.
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Assessment of noise exposure at different ways of rearing water fowl.
BRAUN, Petr
This Bachelor´s work describes the evaluation of noise exposure at different ways of breeding water fowl. Breed selected for measuring the goose Czech. The aim is to measure and verify the intensity of noise arising from the farms and backyard and evaluate that noise acting on the surroundings. The basis is to implement the measurement noise level in backyard farms and are growing in a farm really out of the growing season for selected habitats and compare readings with legislative and hygiene standards. If permissible limits are exceeded measured values, it will be essential to propose the necessary restrictive measures.
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Development of algorithm of imaging methods in diagnostic of knee joint in years 2001 - 2006 in University Hospital Motol
REDLICH, Peter
Knee joint is the biggest and the most complex joint of moving system. Its exceptionality embodies in difficult anatomical structure and static-dynamic function. Elongated human life and increased moving and sport activities lead to higher risk of knee joint injury. In monitored period (2001 {--} 2006), imaging methods of knee joint examinations experienced immense development which would continue in near future. Native skiagraphic examinations remain an inseparable part of algorithm of imaging methods. Though, methods without the use of ionizing radiation: magnetic resonance and ultrasound gain ground. In monitored period, the number of examinations with magnetic resonance markedly increased and continuation of this trend can be expected. That is especially because this method is noninvasive and the diagnostic yield is considerable. In 2001 to 2006, there were carried out totally 35 691 knee examinations for 23 602 667 points at total rate 21 006 565 Kč. Total number of native skiagraphic examinations is almost the same. I noted forceful growth of magnetic resonance examination in 2003 {--} 2006.The numbers of other examinations are without expressive changes. The total price of separate examinations is relatively the same but the total price of magnetic resonance examination is thanks to increasing number of examinations quite high. The results showed that despite of increasing number of magnetic resonance examinations, corresponding decrease of ionizing radiation examination doesn´t happen.
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