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Envolvement of controlled planning documentation in radiotherapy
ZIMOVÁ, Tereza
This diploma thesis deals with the elaboration of managed documentation for yearly Short-term Stability Check of the planning system and identification of critical points, which refer to their lack of security. Documentation of Short-term Stability Check is specified for use with the Eclipse Planning System from Varian Medical Systems, at the Oncology Department of the České Budějovice Hospital, a. s. In the theoretical part, I focused on producing managed documentation and innovations in the sphere of planning system. I described also the cyber security that relates to one of my targets. At first in the practical part I elaborated a draft of managed document for Short-term Stability Check of the planning system based on the internal directive of the České Budějovice Hospital, a.s. The draft will become the managed document after the approval process. Furthermore, in the practical part are defined the most critical points of the methodology, which could have a negative impact on the safely functioning planning system and the whole department in general. Subsequently I analyzed the risk using the KARS method. After evaluation of critical points I described how they are secured and where are situated deficiencies. Measures were proposed based on results of the analysis for their protection. The benefit of this work is a new perspective on the issue of safe using. This analysis shows an expansive concept of safety in using the planning system with an impact on the operation of the entire department.
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Envolvement of Quality Control Tests of Treatment Planning System
ZIMOVÁ, Tereza
This Bachelor´s thesis deals with the treatment planning system Short-term Stability Check. They are carried out according to the Recommendations of the SONS using QUASAR phantoms. These phantoms are expensive, difficult to handle and the methodology for these phantoms of yearly Short-term Stability Check is unnecessarily time consuming. Then it is in the interest of the department that the QUASAR phantoms will be replaced by Inhomogeneity Phantom. Also, the National Radiation Protection Institute lends QUASAR phantoms, so they are not always available. The purpose of this thesis is verified if QUASAR phantoms can be replaced by Inhomogeneity Phantom for Short-term Stability Check. The thesis consists of theoretical and practical parts. The theoretical part deals with the treatment planning system, checks of the ionizing radiation sources and technical equipment. The newly developed methodology is derived from Atomic act and the Recommendation of the SONS and as mentioned above. The treatment planning process and its algorithm are described in an independent chapter. The treatment planning is carried out in the system Eclipse. The system includes many functions, which accelerate the creation, selection and verification of treatment plans. In the following chapter are described the individual checks of the ionizing radiation sources, aimed to verify the accuracy of the devices´ parameters. The Quality Assurance of the ionizing radiation is a condition for the treatment quality and radiation protection of patients and personal. Short-term Stability Check is one of these checks. There is also described the technical equipment, which is necessary for the practical part is impossible. It includes TrueBeam linear accelerator, a 2D detector, phantoms and other equipments, such as wedges, filters. In the practical part there are 2 methodologies, the one of research and the second for Short-term Stability Check of the planning system. The research methodology includes sub-chapters that describe the workflow for Short-term Stability Check. This methodology is based upon information from the manuals of technical equipment. Before introducing the proposed methodology into practice it will be necessary to make its independent verification. Thereafter it will be needed to shorten the methodology to send it to the SONS for assessment. The proposed methodology for Short-term Stability Check of the planning system is in agreement with the on Recommendation of the SONS. In the practical part was verified the planned dose in the planning system Eclipse with measured dose only for checks with inhomogeneities. In this study is formulated the hypothesis: "Can be assumed partial or complete replacement phantoms from the firms Modus or AGMECO by Inhomogeneity Phantom supplied by the PTW company". To confirm or refute the hypothesis was collected data of individual doses. Data collection was performed by irradiating the measurement setup: the detector Octavius 729 + Inhomogeneity Phantom + appropriate number of added plates. In total four energies, 6X, 18X, 6XFFF and 10XFFF were used. Data evaluation was provided by gamma analysis, which assesses the location and size of the point in the dose matrix according to previously specified criteria. The criteria were determined by the table Tolerance. These criteria were verified at most of points. The important thing was that the criterion of 10.0 mm; 10.0% required by Recommendation of the SONS was fulfilled by all points, because it concerns a build-up area, penumbra and interfaces with inhomogeneity's. The research was successfull. It confirmed the hypothesis that QUASAR phantoms may be completely replaced by Inhomogeneity Phantom. In case of practical implementation of this methodology, it should facilitate the work and reduce significantly the time needed to perform the checks.
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Verification of nondosimetric parameters of planning systems
ZAPLETALOVÁ, Barbara
During the recent years radio-therapy has developed significantly in the Czech Republic. Contemporary planning systems enable us to send on-line both input (CT, MR) and output data (simulator, verification system). The overall exactness of the radio-therapeutic treatment of patients is dependent significantly on the accuracy and reliability of the planning system. Thus, the planning system should be evaluated as a significant item in terms of the radiation protection and its properties and functions must be checked regularly. Before starting the TPS operation, an acceptance test must be performed and in the course of using it regular tests of the operation stability should be carried out. At present, only some working places apply thoroughly the programme of securing the quality of planning systems. Attention is usually paid only to dosimeter variables, that is, verifying the correct dose distribution. Planning systems, however, in connection with the computer tomography (CT) have many more other non-dosimeter functions. They include: gaining CT pictures, their transmission into TPS, functions for creating the outer contour of the patient as well as the contour of the inner structures, manipulation with the contours, the reconstruction of scissions, digitally reconstructed radiographs, conversion of the CT number - relative electron density (RED), calculation of volumes of structures, the geometric scheme of clusters, etc. The aim of my bachelor thesis is to verify the usage of CT phantoms (TOS) supplied on a regular basis for checking the non-dosimeter variables of planning systems for radio-therapy. At present the tests are carried out with the help of the so-called QUASAR phantoms, which must be borrowed from the State Board of Radiation Protection.
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Carrying out stability tests of X-ray apparatuses and cooperation on developing radiology standards
ŠIMKOVÁ, Veronika
The objective of the paper is to examine correct fiction of X-ray apparatuses at the Radiodiagnostic Station of the Hospital i Jihlava. I tis to estabilish if the chase in conditions that may occur (such as temperature, power failures ETA.) may affect the results of the operational stability tests. The subjekt of this paper is to develop local radiology standards for particular apparatuses based on the ordinances of the State Nuclear Safety Institute. The results shall be processed statistically over the period of one year, represented graphically and set against the results of the State Nuclear Safety Institute. This shall reset in facilitation of the work in the Radiodiagnostic Station in Jihlava.
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Quality of mammographic images and mammographic projections
VOSTŘÁKOVÁ, Michaela
Mammographic examination is highly important considering that breast cancer is the most frequent carcinoma in women in the Czech Republic. Of course, the quality of mammographic images depends on all parts of the imaging chain including a proper scanning technique and proper positioning of the patient as the breast should be sufficiently captured in the highest extent possible, including the pectoral muscle. Proper exposure and general quality of the images are also necessary in order to show discrete calcifications that may be the single sign of any pathological process in the breast. This thesis is aimed at evaluating the quality of mammographic imaging at two screening departments. One department has undergone complete digitization, the other applies classical film-based mammography. Mammography devices were replaced with digital ones at the film-based mammography department during this research. The result of this work consists in comparing the imaging quality at both these departments, completed with comparison of film-based and digital mammography at the department where the devices were replaced.
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Stability parameters CT parts of hybrid camera SPECT/CT ( Infinia/Hawkeye ) in daily verification
JURSA, Radek
Act No. 18/1997 Coll., on Peaceful Use of Nucelar Energy and Ionising became effective in 1997. This Act governs the responsibilities of operators of the facilities utilizinig ionising amnong others. This radiation is used in a high degrese in medical sphere whether for the diagnostic or therapeutic purposes. Even displaying by means of radiation has undisputed avantages, every its using means potential danger for the patient{\crq}s health. It{\crq}s necessary to follow radiation health conventions as also regulary perform various tests a measurements of stability parameters of the equipment used for ionisation, in order to minimize risk of irradiation. This thesis has both theoretical and practical parts. I try to give comprehensive view on the Atomic Act and its paragraphs in the theoretical part. And in practical part, I pay attention to execution of daily tests of stability CT part of the SPECT/CT diagnostic tool located in České Budějovice, ward of nuclear medicine.
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Quality control and phantom scintillographic measurements to check the condition of data-visualisation equipment
BLÁHOVÁ, Jana
In its theoretical part, this work is concerned with the equipment and devices used within the nuclear-medicine quality assurance programme, in particular gamma-camera, as well as acceptance and operational tests the purpose of which is to verify parameter compliance in reference to the values determined during the equipment acceptance tests. Special attention is paid to the signal detection quality, activity measurement correctness and precision, the factors influencing the same and the measurement errors. To avoid incorrect interpretation of erroneous measurements results, continuous quality control is required for the instruments intended to detect ionising radiation. Another subject of the theoretical part is quality of the visualisation technique where the poor quality of the final image may result from incorrect setting and/or failures of the visualisation equipment. The final section of the theoretical part reviews the existing fixtures and radiation sources used in calibration and testing of the image properties of scintillation cameras {--} the so-called phantoms. The target of this work is verification of the basic parameters stability of two gamma-cameras and demonstration of the importance of regular scintillographic measurements for the medical examination quality. The practical part of this work is focused on comparison regarding parameter stability of two Siemens SPECT cameras, model E.CAM of different manufacturing dates. Subject to verification were the basic equipment parameters normally tested within the standard operation stability and quality assurance programmes. The measured values have been arranged in tables and shown in graphs, and subject to statistical processing. The results of this work will be used in working out the operational standards for the nuclear medicine department of Faculty Hospital in Lochotín in Plzeň, and may serve as reference data in decision on replacement of outdated equipment and devices.
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