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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Digital X-ray analysis for monitoring fracture healing

Dawson, Sarah P. January 2009 (has links)
X-ray based evaluation of different stages of fracture healing is a well established clinical standard. However, several studies have shown plain radiography alone to be an unreliable method to assess healing. The advent of digital X-ray systems provides the potential to perform quantitative analysis on X-ray images without disrupting normal clinical practice. Two aspects were explored in this study. The first was the measurement of mechanical fracture stiffness under four point bending and axial loading. The second was the inclusion of an Aluminium step wedge to provide Aluminium-equivalent thickness calibration information. Mechanical sti ness studies involved the development of equipment to perform four point bending on intra-medullary (IM) nailed tibial fractures, equipment to perform axial loading on conservatively treated humeral fractures, and fracture models to ex- amine the developed systems. Computational procedures to automatically measure the angle and offset occurring at the fracture site by comparing loaded and unloaded X-ray images were developed utilising cross-correlation. The apparatus and procedures were tested using the fracture models both in X-ray and using the Zwick materials testing machine. The four point bending system was applied clinically to a series of IM nailed tibial fracture patients and the axial loading system to two conservatively treated humeral fracture patients. Mechanical stiffness results showed that the apparatus worked well in the clinical radiography environment and was unobtrusive to normal practice. The developed X-ray analysis procedure provided reliable measurements. However, in the case of IM nailed tibial fractures, both angular and displacement movements were too small to be accurately assessed or to provide reliable stiffness measurements. This indicated that this patient group was possibly unsuitable for mechanical stiffness measurements or that higher loads needed to be applied to the fracture site. The case studies of conservatively treated humeral fractures showed potential in detecting movement between loaded and unloaded X-rays and using this to provide sti ness information. Further investigation is required to show that this technique has the potential to aid fracture healing monitoring. Investigation into Aluminium step wedge calibration began with the design of different step wedges and X-ray phantoms. Initial image analysis involved studying the automatic processing applied by a digital Computed Radiography (CR) Fuji sys- tem and modelling of the inhomogeneities in X-ray images as well as investigation into the effect of and correction for scatter, overlying soft tissue and bone thickness. Computational procedures were developed to semi-automatically detect the steps of the step wedge, form an exponential Aluminium step thickness to grey level calibration graph, measure soft tissue and bone thickness, and correct for the heel effect and scatter contributions. Tests were carried out on pre-clinical models and results compared to ash weight and peripheral quantitative computed tomography (pQCT). A clinical study of radial fractures was used to investigate the effectiveness of the step wedge calibration system in monitoring fracture healing changes. Results using the step wedge indicated that the calibration technique was e ective in detecting and correcting for aspects in uencing Aluminium-equivalent thickness measures. With careful processing, useful information was obtained from digital X- rays that included the Aluminium step wedge and these correlated well with existing density measures. The use of the wedge in patient images showed that small increases in Aluminium-equivalent thickness of the fracture site could be detected. This was most useful for intra-patient comparisons throughout the course of healing rather than providing quantitative measurements which were comparable to other density measures. In conclusion, this thesis shows the potential for accurate analysis of digital X- rays to aid the monitoring of healing changes in fracture patients, particularly with application of axial loading and the use of step wedge calibration.
322

The use of technetium 99m hexa-methyl propylene amine oxime spect scanning in acute stroke management.

Winterton, Ruth January 1991 (has links)
A short report submitted to the Faculty of Medicine, University of the Witwatersrand in partial fulfilment of the requirements for the degree of Master of Medicine in Nuclear Medicine / 19 patients were selected, from the patients screened, for investigation within 48 hours of the onset of an ischaemic cerebrovascular accident. Clinical neurulogical scoring, computerized tomography lCT) scans and single photon emission computed tomography (SPECT) scans were performed on day 1, day 10 and day 30. SPECT scan data was analysed by 5 semi-quantitative methods, and findings were compared with neuroloyical clinical scores on each respective day. It was found that day 1 SPECT scans are of value for early localization of the acute ischaemic infarction. A multiple regression model was developed using both the day 30 Defect Volume index and segmental analysis score which related to the day 30 clinical scores. The day 1 model was unsatisfactory and no such model was found relating day 10 SPECT semi-quantitative methods to day 10 clinical scoring. Changes in semi-quantitative scores from day 1 to day 30 did not correlate with clinical changes. Longer follow up may be required for there to be value in performing SPECT scans in stroke trials. A prognostic equation was derived by multiple regression analysis of day 1 SPECT scan scores and day 30 clinical scores. / Andrew Chakane 2019
323

Avaliação radiográfica do nível ósseo de pacientes em manutenção periodontal\" / Radiographic assessment of the alveolar bone level of patients in Periodontal Maintenance

Fukuda, Cassia Tiemi 03 April 2006 (has links)
A presente investigação propôs-se a realizar uma análise radiográfica de pacientes em manutenção periodontal do Programa de Pós-Graduação da Disciplina de Periodontia da Faculdade de Odontologia da Universidade de São Paulo. A porcentagem da perda óssea alveolar foi correlacionada com a idade, o fumo , o gênero, os arcos, os grupos de dentes e faces proximais por meio de exames radiográficos completos periapicais. A amostra deste trabalho foi composta por 27 sujeitos da pesquisa do gênero masculino e 53 do gênero feminino, com idade de 16 a 84 anos (média de 48,3 anos). Foram digitalizadas 1120 radiografias periapicais (1970 dentes) e posteriormente, analisadas com o software Image Tool ® (University of Texas Health and Science Center). O critério utilizado para se considerar perda óssea foi que a distância junção esmalte cemento (JEC) à crista óssea alveolar (COA) fosse > que 2 mm. Dois examinadores calibrados (p < 0,0001), realizaram as medidas da perda óssea. A média da perda óssea da amostra foi 20,61% (± 12,12). A prevalência foi maior em fumantes. No entanto, não houve diferença entre homens e mulheres (p > 0,05). A superfície distal e a arco superior apresentaram maiores perdas, bem como o grupo de incisivos e molares superiores. O grupo etário que apresentou maior perda óssea foi o de 45 a 54 anos. O fumo e a faixa etária de 45 a 54 anos são as variáveis que, isoladamente, apresentaram indivíduos com maior susceptibilidade à perda óssea alveolar, quando avaliada radiograficamente. / The aim of the present investigation was to perform a radiographic analysis of patients in Periodontal Maintenance from the Department of Periodontology Graduation - Dentistry College University of São Paulo. Complete sets of periapical radiographs provided data for alveolar bone loss percentage which was correlated to age, smoking status, gender, arches, teeth group and proximal sites. The sample was consisted of 27 male and 53 female subjects with age from 16 to 84 years old (mean 48,3 years). 1120 radiographs (1970 teeth) were digitalized and analyzed with the software Image Tool ® (University of Texas - Health and Science Center). The criteria used to consider bone loss was when the distance from the cement enamel junction to the apex was greater than 2 mm. Two examiners, intra and inter calibrated (p < 0,0001) were responsible for taking the radiographic measurements of bone loss. The mean bone loss of the sample was 20,61%. The prevalence of bone loss was greater in smokers. Nevertheless, there was no difference between male and female (p < 0,0005). The distal surface and the superior arch had the greatest bone loss, as well as the group of incisors and superior molars. The age group of 45- 54 had the highest scores for bone loss. Smoking and group age from 45 to 54 years are two independent variables that may characterize those individuals most prone to alveolar bone loss.
324

Estudo da hiperplasia do processo coronóide em radiografias panorâmicas com enfoque na observação clínica / coronoid process hyperplasia Study through panoramic radiography focusing on clinical observation

Lima, Patrizia Dubinskas Moruzzi 04 December 2007 (has links)
A hiperplasia do processo coronóide (HPC) é uma variação morfológica que causa limitação na abertura de boca interferindo na mastigação. Normalmente não apresenta sintomatologia dolorosa e o paciente só vai procurar tratamento quando houver dor ou problemas funcionais causados pela compressão do processo coronóide hiperplásico no osso zigomático. Muitos clínicos desconhecem esta alteração e adotam tratamento para disfunção da articulação temporomandibular (ATM). Neste trabalho propôs-se mostrar que a hiperplasia do processo coronóide pode ser observada em radiografias panorâmicas de forma a suspeitar da existência dessa alteração e, aliado aos dados clínicos, o cirurgião-dentista generalista possa encaminhar o paciente ao especialista para que sejam providenciados exames mais complexos que permitam a conclusão do diagnóstico. A amostra constituiu-se de 150 radiografias panorâmicas dentre as quais estavam incluídas imagens sugestivas da hiperplasia do processo coronóide (HPC). Estas radiografias foram submetidas à análise de 3 Radiologistas com um mínimo de 5 anos de experiência na especialidade. Ficou concluído que a radiografia panorâmica é um meio auxiliar para o diagnóstico inicial dessa alteração e o clínico deve estar atento aos possíveis indicativos que esta técnica radiográfica fornece para a sugestão do diagnóstico. / The Coronoid Process Hyperplasia is a morphologic variation, which reduces mouth opening and interferes on mastication. Normally, it doesn\'t have pain symtomatology, and the patient will only look for treatment when there is pain or functional problems caused by compression of the Hyperplasic Coronoid Process on the zygomatic bone. Many practitioners ignore this alteration, and do treatment for termporomandibular joint disorder. This work proposes to show that is possible to suspect the presence of Coronoid Process Hyperplasia on panoramic radiography, and allied with clinical information, general practitioners can forward their patients to a specialist, to make more complex exams which will allow the conclusion of the diagnosis. The sample was composed by 150 panoramic radiographys, where included some suggestive radiographs of Coronoid Process Hyperplasia. These radiographs were analyzed by 3 Radiologists with at least 5 years of experience on this activity. It was concluded that panoramic radiography is an auxiliary way for initial diagnoses of this alteration and practitioners should attent the possible indicatives that this radiograph technique brings for diagnoses suggestion.
325

Estabelecimento de um índice quantitativo e qualitativo para auxiliar no diagnóstico da osteoporose em radiografia panorâmica / Establishment of a quantitative and qualitative index for the diagnosis of osteoporosis in panoramic radiography

Miranda, Lituania Fialho de 12 August 2011 (has links)
Recentemente, a osteoporose tem sido apontada como fator associado a manifestações bucais representadas pela perda óssea, especialmente na mandíbula. Entretanto, as técnicas de avaliação direta da densidade mineral óssea mandibular ainda não demonstraram boa precisão e acurácia. O presente trabalho teve como objetivo avaliar, por meio de um estudo descritivo-analítico, a possibilidade da utilização das radiografias panorâmicas, como um método capaz de expressar as alterações morfológicas da mandíbula decorrentes da idade e estabelecer um único índice quantitativo e qualitativo, para identificar os casos de osteopenia e osteoporose. A pesquisa ocorreu em mulheres em período de menopausa e pós-menopausa em tratamento odontológico nas clínicas odontológicas da faculdade de Odontologia da Universidade de São Paulo, no município de São Paulo SP. A confirmação do diagnóstico da osteoporose foi estabelecida mediante verificação dos relatórios da densitometria de antebraço obtidos, e comparados aos diagnósticos obtidos nas radiografias panorâmicas para o estabelecimento de um único índice quantitativo e qualitativo que considere a reabsorção e a baixa espessura da cortical na avaliação. O novo Índice Panorâmico Quantitativo e Quantitativo (IPQQ) foi determinado. A concordância entre as duas avaliações, calculada como razoável, reflete sensibilidade (moderada) de 56%, especificidade (satisfatória) de 82% e VPN (Valor Preditivo Negativo) de 68%. O IPQQ apresentou associação e concordância significativa com a densitometria (padrão ouro) podendo ser utilizado como teste para o rastreamento, porém cuidados ou algumas restrições deverão ser tomados em sua utilização, pois a intensidade de concordância razoável foi devida a uma moderada sensibilidade deste teste em relação ao padrão ouro. / Recently, osteoporosis has been implicated as being associated with oral manifestations represented by bone loss, especially in the jaw. However, the techniques of direct assessment of mandibular bone mineral density has not demonstrated good accuracy and precision. This study aimed to evaluate, through a descriptive and analytical study, the possibility of the use of panoramic radiographs as a method to express the morphological changes of the jaw due to age and to establish a single index quantitatively and qualitatively, to identify cases of osteopenia and osteoporosis. The research period occurred in women in menopause and postmenopause in dental treatment in dental clinics of the Faculty of Dentistry, University of São Paulo, in São Paulo - SP. Confirmation of the diagnosis of osteoporosis was established by scanning densitometry reports obtained from the forearm, and compared the diagnoses obtained from panoramic radiographs for the establishment of a single index that considers both quantitative and qualitative resorption and lower cortical thickness in the assessment. The new Quantitative and Quantitative Panoramic Index (QQPI) was determined. The agreement between the two assessments, calculated as reasonable, reflects sensitivity (moderate) 56%, specificity (satisfactory) to 82% and NPV (Negative Predictive Value) of 68%. The QQPI showed significant association and agreement with densitometry (gold standard) can be used as a test for the screening, but some restrictions or care should be taken into use, because the intensity of reasonable agreement was due to a moderate sensitivity of this test in compared to the gold standard.
326

Avaliação da densidade mineral óssea por meio da radiografia panorâmica: modificadores e determinantes no resultado / Evaluation of bone mineral density by means of panoramic radiography : modifiers and determining the result

Miranda, Lituania Fialho de 11 December 2014 (has links)
A osteoporose tem sido apontada como grave problema de saúde pública, que compromete a qualidade de vida dos seus portadores. Um dos principais fatores que influencia na prevenção à fraturas provenientes dessa enfermidade é o diagnóstico precoce. O diagnóstico das alterações morfológicas da mandíbula por meio de radiografias panorâmicas (RP) é um método barato, simples e indicado para o rastreamento da desmineralização óssea que mostrou estar associado às alterações sistêmicas. O presente estudo descritivo-analítico objetivou avaliar se existem e quais são as variáveis que podem interferir na determinação do diagnóstico por meio das RPs. Foram analisados dados sócio-biológicos, radiografias panorâmicas e densitometrias ósseas (DO) de um total de 435 pacientes. A análise das RPs foi realizada por meio do Índice Panorâmico Quantitativo e Qualitativo (IPQQ), estabelecido em outra parte desta pesquisa. Essas observações foram então relacionadas aos resultados da DO e às variáveis coletadas no questionário de dados sócio-biológicos. A análise das RPs mostrou estar correlacionada com a DO (kappa = 0,7) e mostrou ainda que pode ser influenciada pelo uso de bisfosfonatos ( p = 0,0137), renda ( p = 0,0264), e perda dentária representada pelas variáveis uso de prótese parcial removível ( p = 0,0249) e prótese parcial fixa ( p = 0,0320). O presente estudo propõe ainda outras investigações conduzidas com desenhos mais rigorosos, para compreensão do problema que ainda guarda muitas lacunas. / Osteoporosis has been identified as a serious public health problem affecting patients\' life quality. One of the major factors that influences fractures prevention from this disease is early diagnosis. The diagnosis of mandible morphological changes using panoramic radiographs (PR) is an inexpensive, simple method suitable for screening bone demineralization associated with systemic changes. This descriptive- analytical study aimed to evaluate whether there are and what are the variables that can interfere in the determination of PRs\' diagnosis. Socio-biological data, PR and bone densitometry (BO) of 435 patients were analyzed. The analysis was performed by RPs\' Quantitative and Qualitative Panoramic Index (QQPI) previously established in another part of this research. These observations were then related to BO results and variables collected from socio-biological data questionnaire. The PR analysis were correlated with BO (kappa = 0.7) and could be influenced by the use of bisphosphonates (p = 0.0137), income (p = 0.0264), and tooth loss, represented by the variables: use of removable partial dentures (p = 0.0249) and use of fixed partial denture (p = 0.0320). This study also suggests the conduction of more rigorous designs researches to understand this problem that still has many gaps.
327

Estudo e caracterização física de cerâmicas indígenas brasileiras / Study and physical characterization of native Brazilian pottery

Curado, Jessica Fleury 20 April 2012 (has links)
O presente trabalho tem por objetivo caracterizar e identificar a natureza de recursos cerâmicos brasileiros utilizando métodos físicos não destrutivos. O estudo está inserido na área interdisciplinar da Arqueometria e envolve a participação de pesquisadores do Museu de Arqueologia e Etnografia da Universidade de São Paulo (MAE-USP). As amostras analisadas são de grande interesse arqueológico, pois foram coletadas em uma região do Pantanal sul-matogrossense que possui um complexo processo de ocupação envolvendo diversas tradições culturais, entre as quais a tradição Guarani e a tradição Pantanal. Os fragmentos cerâmicos foram caracterizados através das técnicas de Emissão de Raios X Induzido por Partícula (PIXE) e Fluorescência de Raios X (XRF) para a determinação da composição da matriz da pasta cerâmica e através da técnica de Radiografia Computadorizada para a investigação da estrutura interna das peças. A técnica PIXE permitiu uma caracterização dos elementos majoritários encontrados na matriz cerâmica (Z<26), usados na previsão do valor da densidade da matriz. A técnica XRF foi utilizada para determinar as concentrações elementares com destaque para os elementos minoritários (Z>26, wt%<5%) presentes na pasta cerâmica. Essas técnicas, quando associadas a métodos de análise estatísticos permitiram um melhor entendimento do conjunto de amostras. Os resultados encontrados apontam uma clara diferença na composição elementar das amostras encontradas nos diferentes sítios arqueológicos e pertencentes às diferentes tradições. Com a aplicação da técnica de Radiografia as amostras foram separadas de acordo com a presença de tempero em sua estrutura e através da análise das imagens radiográficas foi determinada a densidade dos fragmentos. Neste trabalho foi possível estabelecer uma relação entre os fragmentos cerâmicos estudados às suas tradições, assim como aos sítios arqueológicos nos quais foram coletados. / The present work aims to characterize and identify the nature of Brazilian ceramics using non-destructive physical methods. The study is inserted in the interdisciplinary area of the Archaeometry and involves the participation of researchers from the Museum of Archaeology and Ethnography of the University of São Paulo (MAE-USP). The analyzed samples are of great archaeological interest, as they have been collected in a region of Pantanal in the state of Mato Grosso do sul with a complex settlement process that involves different cultural traditions like the Guarani tradition and the tradition Pantanal. The ceramic fragments were characterized through the techniques of X-ray Emission Particle-Induced (PIXE) and X-Ray Fluorescence (XRF) to determine the composition of the matrix of the ceramic paste and using the technique of Computed Radiography for the investigation of internal structure of the sherds. PIXE technique allowed a characterization of majoritarian elements found in ceramic matrix (Z < 26) and was used in the prediction of the density of the paste. XRF technique was used to determine the elemental concentration with emphasis on the minority elements (Z> 26, wt% < 5%) presents in ceramic paste. These techniques, when associated with statistical methods of analysis allow a better understanding of the sample set. The results show a clear difference in the elemental composition of the samples found in different archaeological sites and from different cultural traditions. By applying the technique of X-ray samples were separated according to the presence of temper in its structure and through images was obtained the density of fragments. In this work it was possible to establish a link between the studied ceramic fragments to their traditions, as well as the archaeological sites in which they were collected.
328

The distribution and volume of visceral and subcutaneous adipose tissue, derived from CT examination.

January 1998 (has links)
by Poon Mei Yu. / Thesis submitted in: Dec. 1997. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 127-132). / Abstract also in Chinese. / Declaration --- p.i / Acknowledgement --- p.ii / Table of Contents --- p.iii / Abbreviations --- p.xi / List of Figures --- p.xiv / List of Tables --- p.xvii / Abstract --- p.xxi / Introduction --- p.1 / Chapter Chapter 1: --- Obesity & related abnormalities --- p.2 / Chapter Chapter 2: --- Measurement of body fat --- p.11 / Objective --- p.18 / Chapter Chapter 3: --- Purpose of study --- p.19 / Method --- p.24 / Chapter Chapter 4: --- Technical considerations on CT technique --- p.25 / Chapter Chapter 5: --- Data Collection --- p.32 / Chapter Chapter 6: --- Data Analysis --- p.44 / Results --- p.49 / Chapter Chapter 7: --- Amount of adipose tissue --- p.50 / Chapter Chapter 8: --- "Adipose tissue distribution, VSR & VTR" --- p.81 / Discussion --- p.105 / Chapter Chapter 9: --- Discussion --- p.106 / Conclusions --- p.122 / Chapter Chapter 10: --- Conclusions --- p.123 / References --- p.127 / Appendix I --- p.133 / Appendix II --- p.136 / Appendix III --- p.139 / DECLARATION --- p.i / ACKNOWLEDGEMENT --- p.ii / TABLE OF CONTENTS --- p.iii / Brief Contents --- p.iii / Detailed Contents --- p.v / ABBREVIATIONS --- p.xi / LIST OF FIGURES --- p.xiv / LIST OF TABLES --- p.xvii / ABSTRACT --- p.xxi / INTRODUCTION --- p.1 / Chapter Chapter 1: --- OBESITY & RELATED ABNORMALITIES --- p.2 / Chapter 1.1 --- Adipose Tissue --- p.2 / Chapter 1.2 --- Classification of Adiposity --- p.3 / Chapter 1.3 --- Obesity --- p.5 / Chapter Chapter 2: --- MEASUREMENT OF BODY FAT --- p.11 / Chapter 2.1 --- Methods of Measuring Body Fat --- p.11 / Chapter 2.1.1 --- Non-imaging Methods --- p.12 / Chapter 2.1.2 --- Imaging Methods --- p.13 / Chapter 2.1.2.1 --- Plain radiograph --- p.13 / Chapter 2.1.2.2 --- Ultrasound --- p.13 / Chapter 2.1.2.3 --- Computed tomography --- p.14 / Chapter 2.1.2.4 --- Magnetic resonance imaging --- p.16 / OBJECTIVE --- p.18 / Chapter Chapter 3: --- PURPOSE OF STUDY --- p.19 / Chapter 3.1 --- Objectives --- p.19 / Chapter 3.2 --- Explanation --- p.20 / Chapter 3.2.1 --- Best level of AT area measurement --- p.21 / Chapter 3.2.2 --- Linear AT dimension --- p.22 / Chapter 3.2.3 --- Sex and age differences --- p.22 / Chapter 3.2.4 --- Difference in attenuation interval of fat --- p.23 / METHOD --- p.24 / Chapter Chapter 4: --- TECHNICAL CONSIDERATIONS ON CT TECHNIQUE --- p.25 / Chapter 4.1 --- Defining Anatomy --- p.25 / Chapter 4.1.1 --- Abdominal visceral cavity --- p.26 / Chapter 4.1.1.1 --- Diaphragm --- p.26 / Chapter 4.1.1.2 --- Pelvis --- p.26 / Chapter 4.1.1.3 --- Boundary at mid-potion --- p.27 / Chapter 4.1.2 --- Intra- and retro- peritoneal compartments --- p.28 / Chapter 4.2 --- Attenuation interval of fat --- p.29 / Chapter 4.2.1 --- Distinctive pixel value vs. attenuation interval --- p.30 / Chapter 4.2.2 --- Choice of interval --- p.30 / Chapter Chapter 5: --- DATA COLLECTION --- p.32 / Chapter 5.1 --- Subjects --- p.32 / Chapter 5.2 --- Acquisition --- p.33 / Chapter 5.3 --- Measurement --- p.34 / Chapter 5.3.1 --- AT area measurement --- p.35 / Chapter 5.3.2 --- Linear AT measurement --- p.38 / Chapter 5.3.2.1 --- Subcutaneous AT thickness --- p.38 / Chapter 5.3.2.2 --- Visceral AT thickness --- p.39 / Chapter Chapter 6: --- DATA ANALYSIS --- p.44 / Chapter 6.1 --- Tools --- p.44 / Chapter 6.2 --- Mathematical Assumptions --- p.45 / RESULTS --- p.49 / Chapter Chapter 7: --- AMOUNT OF ADIPOSE TISSUE --- p.50 / Chapter 7.1 --- AT Volumes --- p.50 / Chapter 7.1.1 --- In male and female subgroups --- p.50 / Chapter 7.1.2 --- VAT and SAT increase with TAT --- p.52 / Chapter 7.1.3 --- A VAT volume vs. VAT volume --- p.54 / Chapter 7.2 --- AT Areas at Various Anatomical Levels --- p.55 / Chapter 7.2.1 --- In male and female subgroups --- p.56 / Chapter 7.2.2 --- Correlation between AT volumes and areas --- p.62 / Chapter 7.2.3 --- Prediction of abdominal AT volumes from AT areas --- p.63 / Chapter 7.3 --- Linear AT Dimensions --- p.66 / Chapter 7.3.1 --- Linear SAT dimensions correlated to AT volumes --- p.66 / Chapter 7.3.2 --- Linear VAT dimensions correlated to AT volumes --- p.68 / Chapter 7.3.3 --- Prediction of abdominal SAT volume --- p.70 / Chapter 7.3.4 --- Prediction of abdominal A VAT volume --- p.71 / Chapter 7.3.5 --- Prediction of abdominal TAT volume --- p.72 / Chapter 7.4 --- "AT Measurements, Sex and Age" --- p.73 / Chapter 7.4.1 --- In whole study population --- p.73 / Chapter 7.4.2 --- In male and female subgroups --- p.75 / Chapter 7.5 --- Difference in Attenuation Interval --- p.79 / Chapter Chapter 8: --- DISTRIBUTION OF ADIPOSE TISSUE: VSR & VTR --- p.81 / Chapter 8.1 --- VSR --- p.81 / Chapter 8.1.1 --- Correlation --- p.82 / Chapter 8.1.2 --- Prediction --- p.83 / Chapter 8.1.3 --- Effect of attenuation interval --- p.84 / Chapter 8.1.3.1 --- On VSR value --- p.84 / Chapter 8.1.3.2 --- On correlation and prediction results --- p.86 / Chapter 8.2 --- VTR --- p.88 / Chapter 8.2.1 --- Correlation --- p.88 / Chapter 8.2.2 --- Prediction --- p.89 / Chapter 8.2.3 --- Effect of attenuation interval --- p.91 / Chapter 8.2.3.1 --- On VTR value --- p.91 / Chapter 8.2.3.2 --- On correlation and prediction results --- p.93 / Chapter 8.3 --- VSR vs. VTR --- p.95 / Chapter 8.4 --- "VSR, VTR, Sex and Age" --- p.96 / Chapter 8.4.1 --- Correlation --- p.99 / Chapter 8.4.2 --- Prediction --- p.100 / Chapter 8.4.3 --- VSR and VTR increase with age --- p.101 / DISCUSSION --- p.105 / Chapter Chapter 9: --- DISCUSSION --- p.106 / Chapter 9.1 --- Absolute AT Content (Amount) --- p.106 / Chapter 9.1.1 --- AT areas of various anatomical levels --- p.106 / Chapter 9.1.1.1 --- Correlated to AT volume --- p.107 / Chapter 9.1.1.2 --- Prediction of abdominal A T volume: best level --- p.107 / Chapter 9.1.2 --- Linear AT dimensions --- p.109 / Chapter 9.1.2.1 --- Correlated to AT volume --- p.109 / Chapter 9.1.2.2 --- Prediction of abdominal AT volume --- p.111 / Chapter 9.2 --- AT Distribution Indices: VSR and VTR --- p.112 / Chapter 9.2.1 --- The best level --- p.114 / Chapter 9.3 --- Sex and Age Difference --- p.114 / Chapter 9.3.1 --- absolute AT content --- p.114 / Chapter 9.3.2 --- VSR and VTR --- p.116 / Chapter 9.4 --- Difference in Attenuation Interval --- p.118 / Chapter 9.4.1 --- Absolute AT content --- p.118 / Chapter 9.4.2 --- VSR and VTR --- p.119 / Chapter 9.5 --- Limitations --- p.120 / Chapter 9.5.1 --- Study population --- p.120 / Chapter 9.5.2 --- Differentiation of compartments --- p.121 / CONCLUSIONS --- p.122 / Chapter Chapter 10: --- CONCLUSIONS --- p.123 / Chapter 10.1 --- Absolute AT Content in Abdomen --- p.123 / Chapter 10.2 --- Abdominal AT Distribution --- p.125 / Chapter 10.3 --- Effect of Attenuation Interval --- p.126 / REFERENCES --- p.127 / APPENDIX I: Comparison of study populations & scanning techniques --- p.133 / APPENDIX II: Comparison of definitions of attenuation interval of fat and anatomical compartments --- p.136 / APPENDIX III: Statistical summary of the adipose tissue measurements in this study --- p.139
329

Avaliação radiográfica do nível ósseo de pacientes em manutenção periodontal\" / Radiographic assessment of the alveolar bone level of patients in Periodontal Maintenance

Cassia Tiemi Fukuda 03 April 2006 (has links)
A presente investigação propôs-se a realizar uma análise radiográfica de pacientes em manutenção periodontal do Programa de Pós-Graduação da Disciplina de Periodontia da Faculdade de Odontologia da Universidade de São Paulo. A porcentagem da perda óssea alveolar foi correlacionada com a idade, o fumo , o gênero, os arcos, os grupos de dentes e faces proximais por meio de exames radiográficos completos periapicais. A amostra deste trabalho foi composta por 27 sujeitos da pesquisa do gênero masculino e 53 do gênero feminino, com idade de 16 a 84 anos (média de 48,3 anos). Foram digitalizadas 1120 radiografias periapicais (1970 dentes) e posteriormente, analisadas com o software Image Tool ® (University of Texas Health and Science Center). O critério utilizado para se considerar perda óssea foi que a distância junção esmalte cemento (JEC) à crista óssea alveolar (COA) fosse > que 2 mm. Dois examinadores calibrados (p < 0,0001), realizaram as medidas da perda óssea. A média da perda óssea da amostra foi 20,61% (± 12,12). A prevalência foi maior em fumantes. No entanto, não houve diferença entre homens e mulheres (p > 0,05). A superfície distal e a arco superior apresentaram maiores perdas, bem como o grupo de incisivos e molares superiores. O grupo etário que apresentou maior perda óssea foi o de 45 a 54 anos. O fumo e a faixa etária de 45 a 54 anos são as variáveis que, isoladamente, apresentaram indivíduos com maior susceptibilidade à perda óssea alveolar, quando avaliada radiograficamente. / The aim of the present investigation was to perform a radiographic analysis of patients in Periodontal Maintenance from the Department of Periodontology Graduation - Dentistry College University of São Paulo. Complete sets of periapical radiographs provided data for alveolar bone loss percentage which was correlated to age, smoking status, gender, arches, teeth group and proximal sites. The sample was consisted of 27 male and 53 female subjects with age from 16 to 84 years old (mean 48,3 years). 1120 radiographs (1970 teeth) were digitalized and analyzed with the software Image Tool ® (University of Texas - Health and Science Center). The criteria used to consider bone loss was when the distance from the cement enamel junction to the apex was greater than 2 mm. Two examiners, intra and inter calibrated (p < 0,0001) were responsible for taking the radiographic measurements of bone loss. The mean bone loss of the sample was 20,61%. The prevalence of bone loss was greater in smokers. Nevertheless, there was no difference between male and female (p < 0,0005). The distal surface and the superior arch had the greatest bone loss, as well as the group of incisors and superior molars. The age group of 45- 54 had the highest scores for bone loss. Smoking and group age from 45 to 54 years are two independent variables that may characterize those individuals most prone to alveolar bone loss.
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Avaliação volumétrica por meio da tomografia computadorizada de feixe cônico, dos leitos ósseos potencialmente doadores na região de ramo e mento /

Matai, Caio Vinícius Bardi. January 2012 (has links)
Orientador: Julio Cezar de Melo Castilho / Banca: Francisco Haiter Neto / Banca: Pedro Tortamano Neto / Banca: Samira Esteves Afonso Camargo / Banca: Rafaela Rangel Rosa / Resumo: As tomografias computadorizadas (TCs) tridimensionais (3D) solucionaram em grande parte as inconveniências da sobreposição de estruturas anatômicas comuns aos exames radiográficos convencionais (2D). O propósito neste trabalho foi avaliar por meio da Tomografia computadorizada de feixe cônico (TCFC) qual região oferece maior volume ósseo, se a região de mento ou a região de ramo da mandíbula. Foram selecionados 100 exames de TCFC, de indivíduos com idade de 18 a 89 anos do sexo masculino (50) e do feminino (50) com necessidade de realizar cirurgia para enxertia óssea autógena. Os exames foram avaliados por dois radiologistas treinados, para quantificar o volume ósseo das regiões potencialmente doadoras, que foram avaliadas por diferentes orientações para delimitação do volume potencial do leito doador, utilizando um software para avaliação. Sendo posteriormente avaliados pela análise estatística t de Student, teste de Tukey, correlacionando as diferenças estatísticamente significantes (p < 0,05) entre a avaliação das região mensuradas, por métodos diferentes. Verificou-se o maior potencial doador encontrado na região mentual, chegando a atingir o volume médio de 1,59cm3 contra 1,07cm3 a região de ramo. Concluímos que a região mentual, entre os dentes caninos inferiores, proporciona maior volume ósseo e assim como na revisão da literatura, encontramos maior volume ósseo para a região mentual quando comparada as outras regiões doadoras intraorais, avaliadas neste trabalho. E que a seleção do leito doador de enxerto ósseo autógeno intraoral deve ser principalmente julgada de acordo com o conhecimento anatômico da região eletiva e o domínio técnico/prático cirúrgico do Cirurgião / Abstract: Computed tomography (CT) three-dimensional largely solved the inconvenience of overlapping anatomical accidents common to conventional radiographic. The purpose of this study was to evaluate by cone beam computed tomography (CBCT) the region that offers larger bone volume, the ramus or chin region. Were selected according to the criteria of inclusion and non inclusion, 100 CBCT scans of individuals aged 18-89 years old males (50) and female (50) with need for surgery for autogenous grafting, belonging to a particular clinical CT. The studies were evaluated by two trained radiologists in the program OsiriX ® 4.1.2V to quantify bone volume of potential donor regions, which were evaluated by different guidelines, defining the potential volume of the donor site. Further evaluated by statistical analysis Student's t and Tukey's test, that comproove statistically significant differences (p < 0,05) between the evaluations of the same region by different methods. With the largest potential donor found in the chin region, reaching an volume average of 1,59 cm3 against 1,07 cm3 the ramus region / Doutor

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