Submitted by Haroudo Xavier Filho (haroudo.xavierfo@ufpe.br) on 2016-04-22T18:09:16Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação final Max-FINAL .compressed.pdf: 3341309 bytes, checksum: d495284374075775bce6c91531257a7e (MD5) / Made available in DSpace on 2016-04-22T18:09:16Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação final Max-FINAL .compressed.pdf: 3341309 bytes, checksum: d495284374075775bce6c91531257a7e (MD5) Previous issue date: 2015-08-27 / A tomografia computadorizada (TC) é um dos métodos mais importantes de radiodiagnóstico, porém, pode resultar em altas doses absorvidas pelos pacientes quando comparado com exames radiográficos convencionais. O objetivo deste trabalho é avaliar as doses absorvidas pelos pacientes pediátricos nos procedimentos de tomografia computadorizada de crânio realizados em Recife, Brasil, utilizando o software de simulação computacional CALDose_XCT. Os parâmetros de irradiação para os procedimentos de TC de crânio pediátrico de 108 pacientes foram coletados e divididos nas seguintes faixas etárias: <1; 1 a 5; 5 a 10; e 10 a 15 anos de idade. Os valores de índice volumétrico de kerma ar em TC (CVOL) e produto kerma ar-comprimento para exames completos de TC (PKL,CT) foram estimados para cada exame e comparados com os níveis de referência internacional. Foram estimados os valores das doses absorvidos por órgãos relevantes (cristalino, cérebro, mucosa oral e glândulas salivares) utilizando o CALDose_XCT. Outra simulação foi realizada utilizando um fantoma de cabeça com inclinação de 18º para avaliar a redução da dose absorvida quando se utiliza a inclinação do gantry ou da cabeça do paciente. Os parâmetros de irradiação selecionados na maioria dos exames pediátricos avaliados não estão otimizados, já que foram observados valores maiores ou iguais aos parâmetros recomendados para exames em adultos. A maioria dos valores estimados de CVOL foram menores que os níveis de referência referência internacionais para exames pediátricos de TC. Por outro lado, situação inversa ocorreu com os valores de PKL,CT, devido ao uso de valores elevados de comprimento de varredura, em alguns casos maiores que a cabeça inteira do paciente. A maioria dos exames avaliados resultou em valores estimados de PKL,CT acima dos limites recomendados. A simulação da inclinação da cabeça dos pacientes pediátricos para exames de crânio resultou em redução da dose absorvida pelos olhos, mucosa oral e glândulas salivares, demostrando ser um método eficiente para otimização da proteção radiológica nestes procedimentos. Deste modo, ressalta-se a importância de implementação de um programa de garantia de qualidade no serviço, com o objetivo de otimizar os procedimentos e reduzir o detrimento para os pacientes pediátricos submetidos a exames de tomografia computadorizada. / The computed tomography (CT) is one of the most important methods for radio diagnostics, resulting, however, in high absorbed doses to the patients. The objective of this work is to evaluate the pediatric head CT examinations performed at one hospital in Recife, Brazil, and to estimate the mean absorbed doses to organs using the computational simulation software CALDose_XCT. The irradiation parameters used with 108 pediatric head CT examinations were registered and divided in the following age ranges: <1; 1 to 5; 5 to 10; and 10 to 15 years-old. The volume CT air kerma index (CVOL) and the air kerma-length product for full CT examinations (PKL,CT) were estimated to each examination and compared to international diagnostic reference levels. The mean absorbed doses to relevant organs (eye lens, brain, oral mucosa and salivary glands) were simulated using CALDose_XCT. Another simulation was made using a head phantom tilt of 18º, in order to evaluate the dose reduction to some organs using either the gantry or head tilt. The results showed that the irradiation parameters used in the most of the examinations are not optimized, since it was possible to observe tube potential and current-time product values higher than the recommended values to adult examinations. Most of the CVOL values were lower than the international reference levels for pediatric CT examinations. On the other hand, the contrary was observed with the PKL,CT, due to the use of large scan ranges, in some cases, bigger than the patient’s entire head. The simulation of the patient head tilt resulted in absorbed dose reduction to the eyes, oral mucosa and salivary glands, showing to be an efficient method to optimize the radiological protection of pediatric CT examinations. Thus, it can be highlighted the importance of a quality assurance program in the service, with the objective of optimizing the procedures and reducing the risk to the pediatric patients.

Orientadores: Glaucia Maria Bovi Ambrosano, Camila Pinelli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-27T00:57:29Z (GMT). No. of bitstreams: 1 Costa_ElianaDantasda_M.pdf: 3129735 bytes, checksum: dc57001b021783932e8881c4c94b29ff (MD5) Previous issue date: 2015 / Resumo: A equipe odontológica deve seguir as precauções padrão e utilizar protocolos de controle de infecção para evitar a contaminação cruzada e transmissão de doenças. Na Radiologia Odontológica, o risco para contaminação ocorre principalmente durante a realização dos exames radiográficos intrabucais, pelo contato com saliva e/ou sangue, quando o receptor de imagem é retirado da boca do paciente, ou quando o profissional manipula o equipamento de raios X com as mãos/luvas contaminadas. Assim, a adesão ao controle de infecção em Radiologia é um componente que merece atenção, podendo ser mensurado por meio da aplicação de questionários específicos. Considerando-se a escassez de instrumentos para essa finalidade, o presente estudo teve como objetivo desenvolver e validar um questionário para medir as práticas de controle de infecção em Radiologia Odontológica. O questionário foi desenvolvido após extensa revisão de literatura sobre os trabalhos publicados e consulta aos protocolos de biossegurança disponíveis em agências de saúde nacionais e internacionais. A versão inicial do questionário foi composta por 17 questões de múltipla escolha, relacionadas à higiene das mãos, à utilização de barreiras protetoras de superfícies, e ao tipo de desinfetante utilizado para limpeza/desinfecção. A confiabilidade foi avaliada por meio do teste-reteste, estimada pelo coeficiente de correlação intra-classe (ICC) para as variáveis ordinais e kappa para as dicotômicas. A consistência interna foi verificada pelo coeficiente alfa de Cronbach. Um total de 115 estudantes de Odontologia de 3º a 5º ano de graduação, de duas faculdades públicas e de uma faculdade particular do Estado de São Paulo participaram da fase do teste-reteste. A validade de conteúdo foi realizada por dois comitês de especialistas; o primeiro comitê revisou o conteúdo do questionário, verificando o seu conteúdo e abrangência; o segundo comitê verificou a relevância de cada item do questionário. A validade de constructo foi verificada por meio da análise fatorial e teste de Kruskal-Wallis (para comparação entre os grupos conhecidos), comparando-se a resposta de 641 acadêmicos de Odontologia de 2 faculdades públicas e 4 faculdades particulares do Estado de São Paulo, 20 alunos de doutorado e 15 professores de Radiologia Odontológica. Os resultados indicaram confiabilidade (teste-reteste) satisfatória a excelente (1,000?ICC?0,722); boa a ótima (0,662?kappa?0,913) e ótima consistência interna (alfa de Cronbach =0,88). A etapa de análise do conteúdo pelo comitê de especialistas e análise fatorial resultaram na redução de alguns itens do questionário, que foi aprovado pela equipe de desenvolvimento do questionário. Assim, a versão final do questionário foi composta por 15 questões e 7 domínios. Diferenças estatisticamente significantes (p<0,05) foram observadas entre os estudantes de graduação, doutorandos e professores, para a maioria das respostas, indicando o poder discriminatório do questionário. Concluiu-se que o novo questionário mostrou boas propriedades psicométricas e pode ser uma ferramenta importante para medir a adesão aos protocolos de controle de infecção por profissionais de Odontologia / Abstract: The dental team should follow standard precautions for infection control in order to prevent cross-contamination and disease transmission. In Dental Radiology, the risk of contamination occurs primarily during intraoral radiographs by contacting saliva and/or blood, as well as during removing of image receptor from the patient's mouth, or when the practitioner manipulates the X-ray equipment with contaminated hands/gloves. Thus, adherence to infection control in Dental Radiology is an important component deserves attention and can be measured by using specific questionnaires. Considering the scarcity of instruments for this purpose, this study aimed to develop and validate a questionnaire to evaluate infection control practices in Dental Radiology. The questionnaire was developed after extensive literature review on published papers and on the biosafety protocols available in national and international health agencies. The initial version of the questionnaire consisted of 17 multiple-choice questions related to hands hygiene, surface barrier protection, and cleaning/disinfection. Reliability was assessed by test-retest, using the intra-class correlation coefficient (ICC) for ordinal variables and kappa for dichotomous ones. Internal consistency was assessed by Cronbach's alpha coefficient. A total of 115 dental students in third to fifth years from two public and one private dental schools, in the state of São Paulo, participated in the test- retest reliability. The content validity was performed by two expert committees; the first one reviewed the content and coverage of the questionnaire; the second one determined the relevance of each item of the questionnaire. Construct validity was determined by the factor analysis and the Kruskal-Wallis test (for comparison between known groups), comparing the responses of 641 students from two public and four private dental schools, 20 PhD students and 15 teachers of Dental Radiology. Results indicated (test-retest) satisfactory to excellent reliability (1.000?ICC?0.722); good to great (0.662?kappa?0.913) reliability, and good internal consistency (Cronbach's alpha = 0.88). The content analysis performed by the expert committee and the factor analysis indicated the exclusion of some items, which was approved by the questionnaire development team. Thus, the final version of the questionnaire consisted of 15 questions and 7 domains. Statistically significant differences (p<0.05) were observed among students, doctoral students and teachers, for most of the responses, indicating the discriminatory power of the questionnaire. It was concluded that the new questionnaire showed good psychometric properties, and can be an important tool for measuring adherence to infection control protocols by dental professionals / Mestrado / Radiologia Odontologica / Mestra em Radiologia Odontológica

SAMMANFATTNING Bakgrund Antalet personer som drabbas av kolorektalcancer ökar varje år och är den tredje vanligaste cancersjukdomen i Sverige. Det gör att efterfrågan av undersökningsmetoderna blir större för att man ska kunna ställa en korrekt diagnos och påbörja behandling. DT-kolon är en av undersökningsmetoderna och används ofta som en andrahandsmetod. Syfte Syftet med studien är att undersöka vad DT-kolon har för betydelse vid utredningen av kolorektalcancer. Metod Studien är en systematisk litteraturstudie. Insamling av data har gjorts via databaserna PubMed och CINAHL där vetenskapliga artiklar som uppfyllt inklusionskriterierna och besvarat frågeställningen har kvalitetsgranskats och analyserats. Resultat DT-kolon kan påvisa både koloniska- och extrakoloniska fynd och är en särskilt fördelaktig metod vid lokalisering av extrakoloniska fynd. Vid den preoperativa bedömningen anses DT-kolon vara en betydelsefull metod vid exakt lokalisering av patologier i kolon och rektum och är ett bra komplement till koloskopiundersökningar. DT-kolon ses som en tillförlitlig metod och har en sensitivitet på 94–99.9 %. När CAD används som granskningsmetod vid DT-kolon så ökar sensitiviteten, speciellt vid detektion av patologier som är mindre än 10 mm. Slutsats DT-kolon är en betydelsefull undersökningsmetod vid utredning av kolorektalcancer och av andra patologier i buken, kolon och rektum. Undersökningsmetoden är tillförlitlig med hög sensitivitet och med CAD som granskningsmetod ökar sensitiviteten. En stark fördel är att man får med hela bukområdet vid bildtagning och kan därmed även lokalisera extrakoloniska fynd så som exempelvis metastaser. Man kan även se tarmväggens tjocklek och utvändig kontur av kolon och rektum. Nyckelord Kolorektalcancer, Datortomografi, Kolografi / ABSTRACT Background The number of people suffering from colorectal cancer increases every year and is the third most common cancer disease in Sweden. Therefore the demand increases for the examination methods in order to be able to make a correct diagnosis and start treatment. CT Colonography is one of the methods often used as a secondary method. Aim The purpose of this study is to examine what significance CT Colonography has in the investigation of colorectal cancer. Method This study is a systematic review. The collection of data were made from the databases PubMed and CINAHL. Studies which fulfil the inclusive criteria and answered the aim of this study were quality reviewed and analyized. Result CT Colonography can show colonic findings and is particularly useful to locate extracolonic findings. The method is important in the preoperative evaluation because of its exact localisation rate and is a good compliment to colonoscopy. CT Colonography is a reliable method with a sensitivity at 94–99.9 % which increases when CAD is used as a reading method, especially in the detection of pathology &gt;10 mm. Conclusion CT Colonography is a valuable method in the investigation of colorectal cancer and other pathologies in the abdomen, colon and rectum. It’s a reliable method with a high sensitivity which increases with CAD as a reading method. A strong advantage of this method is that the whole abdomen is visible in the images so the localisation of extracolonic findings can be detected. Keywords Colorectal neoplasms, Computed Tomography, Colonograph

Case Report: Diffuse Large B Cell Lymphoma (DLBCL) is an aggressive tumor of B cells that can arise almost anywhere in the body. It is the most common type of non-Hodgkin lymphoma in adults. We report a case of double hit lymphoma, a rare subtype that has an abnormal MYC and BCL2 gene translocation and occurs in about 5% of DLBCLs. A 58-year-old male with a 15-year smoking history presented with abdominal pain accompanied by weight loss of 20 lbs, night sweats, poor appetite, and fatigue. CT angiogram showed posterior mediastinal mass 3.5x5.6x12.8 cm, massive lymphadenopathy in the retroperitoneum surrounding aorta 10.5x5.2x11cm and a large left upper quadrant mesenteric mass measuring 7.2x10.2x13.6 cm. Left abdominal mass was biopsied and pathology showed DLBCL. FISH showed double hit lymphoma. Bone marrow biopsy and aspiration was negative for involvement. LV EF was 61% per ECHO. Patient underwent PET/CT, which showed extensive adenopathy in the inferior neck, chest, and abdomen, as well as a retroperitoneal mass extending into T10-11 extradural space. International Prognostic Index (IPI) for DLBCL categorized the patient as having a poor prognosis and in the high-intermediate risk group with a 4 year overall survival of 55% and 4 year progression-free survival of 53%. The PET scan results showing multiple extranodal sites was a factor in calculating his prognosis. MRI T spine with contrast showed direct invasion of T9, 10, 11, and 12. Urgent chemotherapy was started with DA-R-EPOCH. Our case demonstrates how imaging predicts the aggressiveness of DLBCL biology. The PET scan is very important in determining the extent of disease and the stage to allow for risk stratification of patients with DLBCL.

Cancer is a widespread type of diseases that each year affects millions of people. It is mainly treated by chemotherapy, surgery or radiation therapy, or a combination of them. One modality of radiation therapy is high dose-rate brachytherapy, used in treatment of for example prostate cancer and gynecologic cancer. Brachytherapy is an invasive treatment in which catheters (hollow needles) or applicators are used to place the highly active radiation source close to or within a tumour. The treatment planning problem, which can be modelled as a mathematical optimization problem, is the topic of this thesis. The treatment planning includes decisions on how many catheters to use and where to place them as well as the dwell times for the radiation source. There are multiple aims with the treatment and these are primarily to give the tumour a radiation dose that is sufficiently high and to give the surrounding healthy tissue and organs (organs at risk) a dose that is sufficiently low. Because these aims are in conflict, modelling the treatment planning gives optimization problems which essentially are multiobjective. To evaluate treatment plans, a concept called dosimetric indices is commonly used and they constitute an essential part of the clinical treatment guidelines. For the tumour, the portion of the volume that receives at least a specified dose is of interest while for an organ at risk it is rather the portion of the volume that receives at most a specified dose. The dosimetric indices are derived from the dose-volume histogram, which for each dose level shows the corresponding dosimetric index. Dose-volume histograms are commonly used to visualise the three-dimensional dose distribution. The research focus of this thesis is mathematical modelling of the treatment planning and properties of optimization models explicitly including dosimetric indices, which the clinical treatment guidelines are based on. Modelling dosimetric indices explicitly yields mixedinteger programs which are computationally demanding to solve. The computing time of the treatment planning is of clinical relevance as the planning is typically conducted while the patient is under anaesthesia. Research topics in this thesis include both studying properties of models, extending and improving models, and developing new optimization models to be able to take more aspects into account in the treatment planning. There are several advantages of using mathematical optimization for treatment planning in comparison to manual planning. First, the treatment planning phase can be shortened compared to the time consuming manual planning. Secondly, also the quality of treatment plans can be improved by using optimization models and algorithms, for example by considering more of the clinically relevant aspects. Finally, with the use of optimization algorithms the requirements of experience and skill level for the planners are lower. This thesis summary contains a literature review over optimization models for treatment planning, including the catheter placement problem. How optimization models consider the multiobjective nature of the treatment planning problem is also discussed.

Trauma care across the globe has evolved greatly over the years. However, trauma remains a major contributor to morbidity and mortality as the third leading cause of death in the United States. It also accounts for a considerable portion of healthcare costs. In light of this, and in order to reduce its adverse impacts, appropriate and effective management is necessary. Emergency Medicine, Trauma Surgery, Interventional Radiology and many other specialties contribute to the acute care of patients in the setting of trauma. Other areas of medicine have shown that a clearly outlined multidisciplinary approach to management can lead to better outcomes and shorter hospital stays, specifically where it pertains to rapid response situations. Interventional Radiology has been found to be effective in managing trauma patients presenting with abdominopelvic injury but a clear approach to when they should be involved has yet to be developed. In fact, studies have shown that precise decision making regarding surgical versus non-operative management of trauma patients is essential to providing appropriate care and improving patient outcomes. In order to accomplish this, Interventional Radiology and Trauma Surgery need to have a prompt, active and collaborative dialogue when patients present with such injuries. A description and analysis of the current approach to management of patients with abdominopelvic trauma and subsequent outcomes at a Level 1 Trauma Center will provide valuable insight into how to establish a protocol that could lead to better selection of minimally invasive interventions and in turn improved patient outcomes. / 2022-02-24T00:00:00Z

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Magister Scientiae Dentium - MSc(Dent) / The research is aimed at investigating and finding alternatives to the physical necessity of producing and storing plaster casts or stone models of the tissues of the mouth. The quest for time and space is universal and the successful management of both results in stress free, financially stable and uncluttered work circumstances. Study models do playa very important role in diagnostics and treatment planning as well as communicating final results in Dentistry, especially in Orthodontic practice. Conventional study models are bulky, fragile, and expensive diagnostic tools produced from impressions taken of the patient's mouth and cast in plaster or stone. The storage of these records creates major space problems, and recalling or retrieving models at some later stage also causes logistical problems. Ideally, the tissues of the mouth could be scanned and from this a 3-D image produced on screen, which could later be milled (machining process of reproducing, explained in Appendix B) if necessary. Three dimensionally accurate, visually pleasing, reproducible, measurable and retrievable records, would be the solution. Computerizing dental records has already revolutionized the industry in the fields of Radiology and written patient data. This information is available at the click of a mouse, and integrated diagnostic tools can be displayed on screen. A thorough investigation of all methods of capturing dental data and 3D images from previously researched and publicized studies was conducted before attempting the latest technology. The final project involved: 1. requesting an introductory and explanatory demonstration on the scanning possibilities in South Africa 2. organizing and attending a demonstration of the laser and contact scanner on study models and impressions. 3. undergoing training in the use of a contact scanner. Computerizing of these results and comparing data derived from analyzing both study models and impressions, manually and digitally. 4. researching and collecting of data with engineering professionals, to establish the validity and viability of this method ( aiming to use uncomplicated, widely accepted and thoroughly applicable basic criteria in all experiments.) 5. evaluation of data statistically by a statistician. Discussion: Digitizing and computerizing of images derived from scanning the models or impressions offers the most attractive alternative for record keeping. Laser scanning disappointed in general due to the relative unavailability in South Africa, the expensive nature of the service elsewhere and limiting factors due to the sensitivity of the laser beam. It is the most promising alternative in future research, because of improved accuracy, higher speed of scanning, uniformity and reproducibility. Contact scanning proved to be available, reliable and adjustable. In most applications, the best results in terms of accuracy and quality of surface finish are obtained using contact scanning. The disadvantage of this method is the time factor and therefore it becomes expensive and economically not viable. The direct scanning of impressions, albeit with laser or contact scanning, remains a scientific and clinical viable option. Conclusion: Digital imaging is still a young technology and many aspects are not yet completely explored. It is a promising technology and its significance is increasing because it opens the door to diagnostic information. Another important development is that the software for digital imaging will become more integrated with other computerized dental applications in the dental office, enabling patient data between different and remote practices to be exchanged more easily. Further progress is not limited by a lack of available image processing tools but rather by our restricted understanding of the various components of diagnostic imaging in dentistry. A Bioengineering exhibition mounted by the University of Munich during a December 2000 conference, displayed a specially adapted CT Scanner that could scan information directly from the mouth. This leads to more possibilities of deriving images without impressions or study casts.

No description available.

Magister Scientiae Dentium - MSc(Dent) / Cephalometric landmark detection is important for accurate diagnosis and treatment planning. The most common cause of random errors, in both computer-aided cephalometry and manual cephalometric analysis, is inconsistency in landmark detection. These methods are time-consuming. As a result, attempts have been made to automate cephalometric analysis, to improve the accuracy and precision of landmark detection whilst also minimizing errors caused by clinician subjectivity.This mini-thesis aimed to determine the precision of two cephalometric landmark identification methods, namely an artificial intelligence programme (BoneFinder®) and a computer-assisted examination software (Dolphin ImagingTM).