Introdução: O laudo radiológico com entrada de dados estruturada proporciona precisão na recuperação de informações, todavia, é menos abrangente que o texto-livre e pode impedir o especialista de descrever um achado importante, não contemplado pela estrutura pré-definida. Portanto, a solução está em interpretar o texto escrito pelo especialista e os transportar para uma estrutura computacional ontológica formalizando o conhecimento. Objetivos: Elaborar e avaliar uma metodologia para estruturação de informações de laudos radiológicos em texto livre que contemple as especificidades brasileiras, incluindo a terminologia empregada. Métodos: Coleta de 1701 laudos radiológicos de ressonância magnética da coluna lombossacra em três instituições distintas. Para estruturar a informação, foram utilizadas técnicas de mineração de texto e conceituação ontológica das unidades lexicais. Dez radiologistas especialistas avaliaram a superestrutura textual e a terminologia extraída e conceituada, por meio de questionário eletrônico onde foram sugeridas 3 superestruturas textuais e 30 termos com a descrição do respectivo conceito. Resultados: A metodologia criada é constituída por 6 passos: 1) coleta dos laudos radiológicos de determinado tipo de exame; 2) decomposição textual; 3) normalização das unidades lexicais; 4) identificação das superestruturas textuais; 5) conceituação dos termos candidatos; 6) avaliação das superestruturas identificadas e da terminologia extraída e conceituada pelos especialistas na linguagem de especialidade estudada. Foram identificadas três superestruturas textuais diferentes. Após processamento automático inicial, 6129 unidades lexicais foram normalizadas obtendo 4568 termos candidatos dos quais 4183 foram conceituados e originaram 727 conceitos. Foram estabelecidas 13963 relações entre termos candidatos e conceitos, e 789 relações entre conceitos. Quanto a adequada descrição dos termos, 40% dos avaliadores concordam plenamente que estão adequados, 60% concordam parcialmente que estão adequados e nenhum avaliador discordou que os termos são adequados. Em relação a quantidade de termos utilizados pelos avaliadores, em sua respectiva instituição, 70% utilizam de 24 a 30 termos e 30% de 16 a 23 termos. A conceituação de um termo foi considerada inadequada por dois avaliadores. Conclusão: A metodologia proposta foi avaliada por radiologistas especialistas que identificaram as diferenças das superestruturas textuais entre as instituições e os termos com a descrição do respectivo conceito. Portanto, foi possível estruturar a informação de laudos radiológicos da coluna lombossacra a partir do texto livre identificando as superestruturas textuais, extraindo as unidades lexicais, normalizando as unidades lexicais e conceituando ontologicamente os termos candidatos preservando a referência com as respectivas partes constituintes dos laudos radiológicos produzidos no contexto brasileiro. / Introduction: The radiological report with structured data entry provides precision in information retrieval, however, is less comprehensive than the text-free and may prevent the expert to describe an important finding, not covered by the pre-defined structure. So the solution is to interpret the text written by expert and carry for a computational framework formalizing the ontological knowledge. Objectives: Develop and evaluate a methodology for structuring information in free text radiology reports that contemplates the Brazilian specifications, including terminology. Methods: 1701 radiological reports of lumbosacral MRI were collected in three different institutions. To structure the information we used techniques of text mining and ontological conceptualization of lexical units extracted. Ten dedicated radiologists evaluated the textual superstructure and terminology extracted by the electronic questionnaire which were suggested textual 3 superstructures and 30 terms with the description of its concept. Results: The established methodology consisted of six steps: 1) collection of radiology reports of certain type of examination; 2) textual decomposition; 3) lexical units normalization; 4) textual superstructures identification ; 5) conceptualization of candidate terms; 6) evaluation of identified superstructures and terminology extracted by experts in the specialized language study. We identified three different textual superstructures. After automatic processing initial 6129 lexical units were normalized getting 4568 candidate terms of which 4183 were conceptualized and originated 727 concepts. 13963 were established relations between candidate terms and concepts and 789 relations between concepts. As for adequate description of the terms, 40% of the evaluators agree fully that are appropriate, 60% somewhat agree that they are adequate and no evaluator disagreed that the terms are adequate. Regarding the number of words used by evaluators in their respective institution using 70% between 24 and 30 terms and 30% from 16 to 23 terms. The conceptualization of a term was considered inadequate by two evaluators. The established methodology consisted of six steps: 1) collection of radiology reports of certain type of examination; 2) textual decomposition; 3) lexical units normalization; 4) textual superstructures identification ; 5) conceptualization of candidate terms; 6) evaluation of identified superstructures and terminology extracted by experts in the specialized language study. Conclusions: The proposed methodology was evaluated by radiologists who identified the differences between the textual superstructures institutions and the terms describing the relevant concept. Therefore, it was possible to structure the information of the lumbosacral spine radiology reports from free text by identifying textual superstructures, extracting lexical units, normalizing the lexical units and conceptualizing the terms ontologically candidates preserving the reference to the respective constituent parts of radiology reports produced in the Brazilian context.

M.Tech. (Radiography) / Satisfied patients are recognized as an important outcome measure for evaluating the quality of medical care provided in a hospital setting. A satisfied patient is more likely to comply with instructions given and cooperate with medical staff during procedures such as special radiographic examinations in the radiography department. In Malawi, studies on patient satisfaction have mostly been confined to doctor – patient interaction and other aspects of the health care service. Very little research has been conducted to explore the experiences of patients undergoing special radiographic examinations. The purpose of this study was to explore the experiences of patients undergoing special radiographic examinations at Kamuzu Central Hospital. A qualitative, contextual, explorative, descriptive approach was used to collect data from patients undergoing special radiographic examinations at Kamuzu Central Hospital in Malawi. Focus group interviews were employed to collect data from the study participants. A total number of 15 patients took part in the study. A content analysis approach was used to analyze the views of the participants. The themes that emerged from the focus group data were: Concerns about delays from reception to receiving radiography results (Radiographs and report); Patients’ experiences with regards to the quality of patient care they received and Concerns about the hospital environment and resources in the radiography department. Guidelines have been proposed to address the themes identified.

M.Tech. / The recent increase in demand for radiotherapy services has led to significant delays in commencement of radical radiation treatment in most centres. Radiobiological principles suggest that a delay in starting radiotherapy may have a negative impact on tumour local control. To cope with the growing demand for radiotherapy, modern improvement models need to be accepted and adapted in radiotherapy departments. The PLAN DO STUDY ACT (PDSA) model is an example of such an improvement model which explores new possibilities of improvement through experimentation. This study aimed to determine the causes of radiotherapy delays, and to develop and implement improvements for reducing radiotherapy delays from patients’ referral to a radiotherapy department to the start of radiotherapy at Gaborone Oncology in Botswana. The objectives were to determine the causes of radiotherapy delays, develop and implement improvements of reducing radiotherapy delays using the PDSA model for improvement, and evaluate the effectiveness of the model. Patients who had received radical radiotherapy for head and neck, breast and cervix tumours were analysed as they are the commonly treated cancers at Gaborone Oncology. A retrospective survey was conducted for one year to establish the causes of radiotherapy delays from patient referral to the department to the start of radiation treatment. The PDSA model for improvement was then implemented and monitored for evidence of improvement from May to December 2008. The PDSA model showed significant reduction in radiotherapy delays at Gaborone Oncology. The results showed a decrease in radiotherapy delays in head and neck, breast and cervix cancers from an average delay time of 18.5 days in May 2008 to 8.6 days by December 2008.

The diploma work presents comprehensive overview of methods of determination of radiological impact on food chains. It describes the determination of radionuclides in groceries in common radiation situation and in unusual radiation situation. Practical part of the work presents two model radiation events. These are radiation event in the territory of Czech Republic and radiation event in the territory of other country and its impact on Czech Republic. In the end both model situations are compared.

BACKGROUND: South Africa bares a significant burden of HIV and imaging is commonly performed as part of the workup for respiratory distress. OBJECTIVES: The aim of this study was to document the prevalence of pulmonary thrombo-embolic disease (PTED) and other findings in HIV-infected patients referred for CT pulmonary angiography (CTPA) for suspected PTED. METHOD: Forty CTPA studies of documented HIV-infected individuals investigated for suspected PTED during a 1-year period were retrieved, anonymised and interpreted by three consultant radiologists. Inter-reader reliability was calculated using Free Marginal multi-rater Kappa. RESULTS: Fourteen of the forty cases (35%) were positive for PTED. In the pulmonary embolism (PE)-positive group, 57.14% had peripheral disease and 42.86% had both peripheral and central disease. Associated findings in the PE-positive cases were pulmonary infarcts (17.5%), mosaic attenuation (17.5%) and linear atelectasis (7.5%). The most common incidental findings were solid pulmonary nodules (52.5%), non-wedge-shaped consolidation (45%), cardiomegaly (52.5%) and enlarged intra-thoracic lymph nodes (52.5%). Thirty per cent of the study population had findings related directly to the presence of PTED, whilst most cases in the study (77.5%) had pulmonary findings unrelated to PTED. In the PE-negative cases, 55% reported emergent findings that warranted immediate or urgent medical attention. CONCLUSION: Computed tomography pulmonary angiography imaging is critical for diagnosing PE. However, further investigation into the judicious application of CTPA in HIV-infected patients with suspected PTED is required, as CTPA findings in most of the cases in this study were unrelated to PE.

<p> A new parameter-free texture feature-based seeded region growing algorithm is proposed in this dissertation for automated segmentation of organs in abdominal MR images. This algorithm requires that a user only mouse clicks twice to identify the upper left and lower right corners of a rectangular region of interest (ROI). With this given ROI, a seed point is automatically selected based on homogeneity criteria. Intensity as well as four texture features: 20 cooccurrence texture features, Gabor texture feature, and both 20 and 3D semivariogram texture features are extracted from the image and a seeded region growing algorithm is performed on these feature spaces. A threshold is then obtained by taking a lower value just before the one which results in an ' explosion '. An optional Snake post-processing tool is also provided to obtain better organ delineation. The comparative results of the texture features and intensity are reported using both normal digital images and abdominal MR images acquired from ten patients. Comparisons of Before and After Snake are also presented. Generally, Gabor texture feature is found to perform the best among all features . The experimental results of the proposed approach show that it is fast and accurate when combined with Gabor texture feature or intensity feature and should prove a boon to production radiological batch processing. </p> / Thesis / Doctor of Philosophy (PhD)

Depuis plusieurs années, la Haute Autorité de Santé favorise la diffusion des démarches d'évaluation des pratiques des professionnels de santé. L'idée est de faire progresser la qualité et la sécurité des traitements endodontiques réalisés dans un Centre de Soins et de traitements dentaires en analysant le résultat des traitements réalisés par rapport à des recommandations de bonnes pratiques, puis en mettant en oeuvre des actions d'amélioration. L'évaluation du traitement endodontique a fait l'objet de nombreuses études publiées au cours de ces dernières années. Les résultats hétérogènes rapportés reflètent des différences considérables entre les études concernant notamment l'échantillonnage (type et nombre de dents composant l'échantillon, sélection des cas cliniques), le traitement (procédures, techniques, restauration), et la méthodologie utilisée (conception de l'étude, interprétation radiographique, période de suivi, analyses, mesures des résultats, et critères de succès/échec. Ce travail vise à définir les critères de qualité d'un traitement endodontique afin d'évaluer si les traitements endodontiques réalisés dans le service d'odontologie du CHU de Clermont satisfont ces critères. Une revue de la littérature permet d'établir que 3 critères relevés sur les radiographies postopératoires permettent de décrire le résultat du traitement endodontique. La longueur de l'obturation, sa densité et le fait que l'ensemble du réseau canalaire est concerné par le traitement peuvent être associés en un indicateur mixte qui reflète avant tout le résultat de la phase instrumentale de la procédure. Dans une deuxième partie, cet indicateur composite a été utilisé dans une étude rétrospective des traitements endodontiques réalisés par les étudiants de 4ème et 5ème année au CHU de Clermont-Ferrand. Les critères de qualité technique des traitements impliquaient : 1°) que la limite de l'obturation soit située dans les 2 mm apicaux (pour toutes les racines) ; 2°) que l'image de l'obturation reflète soit dense, homogène et n'incluant pas de vides ; 3°) que tous les canaux visibles et/ou attendus soient obturés. Cette étude rapporte un taux de succès de 58%, valeur relativement haute, par rapport aux études similaires qui varient de 26 % à 57%. Ce pourcentage est dépendant du type de dent, de son état pulpaire, mais ne dépend pas ni de l'expérience de l'étudiant, ni de l'état périapicale. Cet indicateur a également été utilisé dans une deuxième étude qui est la première à fournir des données qualitatives et quantitatives sur les traitements endodontiques réalisés sous anesthésie générale. La qualité technique des traitements sous anesthésie générale est équivalente à celle qui est acceptée par des critères académiques dans les services hospitalo-universitaires. Cette première analyse encourage la réalisation de soins endodontiques sous anesthésie générale et fait la promotion des indications d'anesthésie générale chez l'adulte à des fins de soins dentaires conservateurs. Le pourcentage de traitements endodontiques réalisés dans le respect des recommandations professionnelles de la HAS et satisfaisant les standards académiques des traitements endodontiques constitue un indicateur de qualité des soins. Les deux études qui supportent cette thèse révèlent que les valeurs de cet indicateur pourraient être améliorées. / No abstract available

The thesis derives from the needs of institutions using sources of ionizing radiation to implement a new legislative regarding nuclear law, effective since 1st January 2017. The thesis is focused on radiological events at radiological institutions of chosen healthcare facilities. The theoretical part makes the reader familiar with the term "radiological event", generally elaborates on the field of diagnostic radiography and radiation protection. The practical part of the thesis deals with evaluation of the most occurring causes and the frequency of radiological events, obtained from the records of medical irradiation, even of wrongly carried out exposures in chosen diagnostic radiography institutions and wrongly sorted radiological events to a relevant category. To fulfil all the goals of the master thesis and to apply the results of the work in practice, also the contents of following document were evaluated - "Evaluation of the means of radiation protection", which every holder of permission to work with ionizing radiation has to submit to the SŮJB yearly, till 30th April, with the data from the previous year. This rule is valid since the new nuclear law was adopted. The results of this thesis served the chosen institution to create such report till 30th April 2019, with a broader extent of the analysis and evaluation than last year. The maximal detail of the report about causes and frequency of radiological events and mapping the real situation at the facilities serves also to the State Office for Nuclear Safety (SONS) to create a Recommendation of the SONS regarding the radiological events. Equally, the thesis was beneficial to the observed facilities, to realise the causes and frequency of radiological events in individual years. It is then up to an individual institution and to the employee supervising the radiation protection, to evaluate the consequences of the found causes, for example to point them out within a yearly training of radiation employees, and to consistently see to the compliance of all preventive measures, which proposal and implementation also belongs to the main tasks of the supervisor.

Orientador: Marco Antônio Rodrigues Fernandes / Resumo: A proposta do trabalho é a elaboração de um Plano de Radioproteção e a apresentação da rotina de procedimentos de dosimetria de feixes de teleterapia para a adequação em serviços de radioterapia dedicados à medicina veterinária. São apresentados os principais parâmetros radiométricos dos feixes de radiação que devem ser analisados com maior periodicidade pelos usuários de equipamentos de teleterapia. Os experimentos dosimétricos foram realizados no acelerador linear instalado no Setor Técnico de Radioterapia do Hospital das Clinicas da Faculdade de Medicina de Botucatu. Os ensaios de planura, simetria e de determinação da dose absoluta dos feixes de radiação mostraram-se exequíveis para a rotina da radioterapia veterinária. Os resultados apresentados dos parâmetros radiométricos medidos estão em conformidade com os protocolos de dosimetria nacionais e internacionais. O Plano de Radioproteção elaborado, pode subsidiar os profissionais e autoridades sanitárias envolvidas nas práticas da radioterapia veterinária quanto aos preceitos do uso seguro das fontes radioativas e feixes de teleterapia. / Abstract: The proposal of the work is the elaboration of a Radioprotection Plan and the presentation of the routine of dosimetry procedures of teletherapy beams for the adequacy in radiotherapy services dedicated to veterinary medicine. Presented the main radiometric parameters of the radiation beams that should be analyzed more frequently by users of teletherapy equipment. The dosimetric experiments were performed in the linear accelerator installed in the Technical Section of Radiotherapy of the Clinical Hospital of the Botucatu Medical School. The tests of flatness, symmetry and absolute dose determination of the radiation beams were shown feasible for the routine of veterinary radiotherapy. The presented results of the radiometric parameters measured are in accordance with national and international dosimetry protocols. The Radioprotection Plan elaborated may support the professionals and health authorities involved in veterinary radiotherapy practices regarding the safe use of radioactive sources and teletherapy beams. / Mestre

Um programa de monitoramento para fins de proteção radiológica deve mostrar como ele auxilia na obtenção e demonstração de um grau de proteção adequado e comprovar que as condições de trabalho continuam satisfatórias com o transcorrer do tempo. Para o controle operacional das exposições à radiação ionizante em qualquer local de trabalho, a Comissão Internacional de Proteção Radiológica (CIPR) recomenda um programa de proteção radiológica operacional, proporcional ao grau de risco, para garantir o gerenciamento efetivo das medidas necessárias para se satisfazer o principio da otimização. O presente trabalho de pesquisa tem como premissa o potencial das Tecnologias da Informação e Comunicação (TIC) como ferramenta para a comunicação e disseminação do conhecimento em Proteção Radiológica. O trabalho inclui a informatização da filosofia e técnica do monitoramento e sua otimização, unificando e inter-relacionando informações advindas de diversas publicações nacionais e internacionais, oferecendo às instalações radiativas brasileiras um veículo completo para informação e pesquisa, que permite dimensionar os esforços de otimização tornando-os eficazes e justificados. O sistema oferece ainda tópicos de discussões no intuito de ampliar o repertório dos profissionais do campo da proteção radiológica, suscitando novas reflexões a favor da segurança. Trata-se dos temas desenvolvidos nesta tese, a saber: a necessidade de um monitoramento auditor e discussões mais aprofundadas sobre as exposições potenciais. As reflexões propostas na presente tese vêm ao encontro das novas exigências internacionais, propondo ações passíveis de serem incorporadas na prática laboral. Dentro dos princípios da proteção radiológica, a implementação de um programa de monitoramento auditor permite avaliar se os critérios e ações previamente estabelecidas pelo Serviço de Proteção Radiológica são ou não atendidos, se foram implementados com eficácia e se permanecem adequados. Os fatos resultantes dos procedimentos de auditoria auxiliam a detectar deficiências no processo, possibilitando conclusões e recomendações diante de possíveis fatores desencadeadores de exposições indevidas. Por meio de exames sistemáticos das atividades realizadas em cada tipo de monitoramento, a auditoria infere segurança ao processo, respaldando o trabalhador na realização do monitoramento relacionado com a tarefa e respaldando a instalação, que empreende ações responsáveis a favor da segurança. Em relação às exposições potenciais, somente duas publicações da CIPR são expressivas e desenvolvem o assunto. Entretanto, ainda que forneçam a fundamentação teórica, são incompletas em seus exemplos. Há uma grande falta de conhecimento das probabilidades de falhas, o que atualmente constitui um vasto campo de pesquisa da proteção radiológica. A presente tese propõe, a partir de árvores de falhas, caminhos que auxiliam a quantificar probabilisticamente a ocorrência das exposições potenciais e a probabilidade de se atingir um determinado valor da dose. Acreditamos que o potencial das TIC contribuirá largamente para a disseminação da informação para as instalações radiativas, estimulando o desenvolvimento neste país de grandes extensões territoriais, onde permanece um desafio oferecer o acesso à informação ao maior número de pessoas possível, minimizando custos e maximizando resultados. / A monitoring program for the purposes of radiological protection should demonstrate an adequate protection degree and prove that working conditions remain appropriate as time goes by. For operational control of exposures to ionizing radiation in any workplace, the International Comission on Radiation Protection (ICRP) recommends establishing a program of operational radiation protection, proportional to the risk, to ensure the effective management of all necessary measures to satisfy the principle of optimization. This research work focus on the potential value of Information and Communication Technologies (ICTs) to enhance communication and education on Radiological Protection throughout Brazil. The work includes the informatization of the monitoring policy and techniques, interrelating information currently scattered in several documents, providing Brazilian radioactive facilities a complete repository for research, consultation and information, which allows to size optimization efforts by technology, enabling them to be effective and justified. The content of monitoring programs involves not only the collection and interrelationship of existing information in the publications, but also new approaches from some recommendations, presenting some initiatives towards safety. In this sense, the two contents researched and expanded are: the need for an auditor monitoring and discussions on potential exposures. The recommendations proposed in this thesis meet the new international requirements stablished by the International Agency of Nuclear Energy (IAEA) and propose appropriate actions to be incorporated into labor practice. Respecting the scope of the principles of radiological protection, an auditing program permits to evaluate whether criteria and actions previously established by Radiological Protection Service are effectively implemented and remain appropriate as time goes by. The results of auditing procedures help to detect deficiencies in the process, enabling conclusions and recommendations, avoiding possible triggers of undue exposures. Through systematic examinations of activities in each type of monitoring, auditing attempt to ensure the process, supporting the employee in performing task-related monitoring and support the facility that choose responsible actions towards safety. Furthermore, regarding potential exposures, only two publications of ICRP develop expressively the issue. Even though these publications provide the fundamental theory, they are incomplete in their examples. There is still lack of knowledge of failure probabilities, which currently constitutes a broad research field in radiological protection. This research work proposes the development of fault trees, suggesting paths to quantify probabilistically the occurrence of potential exposures, as well as probabilities to reach a certain level of dose. We believe that the potential of ICT shall contribute greatly to provide information where it is needed, stimulating development in this large country where it is a strong challenge to ensure access to information to as many people as possible, minimizing costs and optimizing results.