• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • Tagged with
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 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.
1

Tomografia computadorizada de t?rax em crian?as : podemos fazer um exame com a dose semelhante a de um raio x de t?rax e sem anestesia?

Dorneles, Cristina Manera 31 August 2016 (has links)
Submitted by PPG Pediatria e Sa?de da Crian?a (pediatria-pg@pucrs.br) on 2017-10-09T17:27:41Z No. of bitstreams: 1 Disserta??o Cristina Manera.pdf: 1861857 bytes, checksum: 55d02acda533fde326a0ac0a092db0ed (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-10-10T13:01:18Z (GMT) No. of bitstreams: 1 Disserta??o Cristina Manera.pdf: 1861857 bytes, checksum: 55d02acda533fde326a0ac0a092db0ed (MD5) / Made available in DSpace on 2017-10-10T13:03:42Z (GMT). No. of bitstreams: 1 Disserta??o Cristina Manera.pdf: 1861857 bytes, checksum: 55d02acda533fde326a0ac0a092db0ed (MD5) Previous issue date: 2016-08-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Objective: To evaluate the technical quality of low-dose computed tomography without contrast and without the use of anesthesia in the diagnosis of lung diseases in children Materials and Methods: It reviewed 86 chest CT scans performed due to clinical indications of acute or chronic inflammatory lung diseases, cancer or congenital malformations in patients from 1 to 18 years of age who were subjected to a low dose of radiation dose bellow the dose recommended by the ALARA and using interactive image reconstruction filters performed without the use of anesthesia or sedation. The exams will be evaluated by two reviewers and age, gender, the radiation dose, image quality and image noise will be assessed. Image analysis will be quantitative. The variables will be the outside Roi diameter of trachea divided by the Roi of trachea, the percentage of axial images with motion artifacts, and identification of the tracheal, the main and segmental bronchi? 20 segments, the main and lobar pulmonary arteries and the ascending aorta artery. The presence of pleural effusion and the identification of paratracheal and subcarinal lymph node chains will also be assessed. Data will be analyzed by for mean, standard deviation and the correlation of the data will be analyzed by tests of Pearson and Spearman, considering significant a p<0.05. Results: The average age of the patients was 5.5 years. LSD as well with the LID, LSE and LIE were displayed in all tests. The middle lobe in almost all (n = 85) apical segment and the medial basilar segment were seen in almost all of the scans (n = 84). The aorta and pulmonary arteries were distinguished on all tomography examinations. The percentage of images with motion artifact introduced an average of 0.8 with IC: 0-2.9 (P25-P75) with p < 0.001. The noise of the image showed an average of 45.5 with 12.4DP. How much ROI the trachea and main bronchi were seen in all the CT scans. The image quality was considered excellent and blurring that didn't compromise the evaluation in almost all the tests. The DLP in mGy dose presented an average of 27.5 with DP ? 11.1. Conclusion: The dose used was significantly lower than the one used in children and allowed the visualization of lung structures in almost all patients, enabling the final diagnosis of cystic fibrosis, bronchiolitis and congenital malformations without difficulty of diagnosis by image artifact / Objetivo: Avaliar a qualidade t?cnica da Tomografia Computadorizada de baixa dose sem contraste e sem anestesia no diagn?stico de doen?as pulmonares em crian?as e adolescentes. Materiais e m?todos: Estudo descritivo retrospectivo em que foram analisadas 86 Tomografias Computadorizadas de t?rax em pacientes pedi?tricos e adolescentes. Os exames foram realizados por indica??o clinica de suspeita de patologias pulmonares com baixa dose de radia??o e com filtro de reconstru??o interativa da imagem sem uso de anestesia ou seda??o. Estes exames foram analisados por dois avaliadores independentes e as vari?veis medidas foram idade, o sexo, a dose de radia??o, a qualidade da imagem, o ru?do de imagem, o ROI externo dividido pelo um ROI na traqueia, identifica??o da traqueia, dos br?nquios principais e segmentares-20 segmentos , das art?rias pulmonares principais e lobares, aorta ascendente, presen?a de derrame pleural, cadeias linfonodais paratraqueais e subcarinal Todas as imagens tamb?m foram medidas quanto a artefato de movimento e foram descritos em porcentagem comparando com o total de imagens. Os dados foram analisados com m?dia, desvio padr?o. Para a an?lise da correla??o foram usados os ?ndices de Pearson e de Spearman considerando um p < 0,01 como significativo. Resultados: A visualiza??o da traqueia e dos br?nquios principais foi poss?vel em 100% dos exames. Os linfonodos paratraqueais e os subcarinais foram visto em todos os exames na bronquiolite e na malforma??o cong?nita. Os lobos superior, m?dio e inferior direito foram visualizados na totalidade das Tomografias Computadorizadas com baixa dose de radia??o nos pacientes com fibrose c?stica e bronquiolite. Na malforma??o cong?nita os lobos superior e inferior direitos foram visualizados em todos exames. Os lobos superior e inferior esquerdos foram identificados em todas as an?lises por TC. Os segmentos apicais foram vistos em 100% das imagens na FC, BO e malforma??o cong?nita.O segmento basilar apical foi visto em todas as imagens na FC. As art?rias aorta e pulmonar foram distinguidas no total dos exames Em nenhum exame houve comprometimento da qualidade da imagem. Na malforma??o cong?nita a percentagem de imagem com excelente qualidade e borramento leve sem comprometimento da avalia??o foram encontradas em todos os exames tomogr?ficos. A porcentagem de artefato de imagem foi de 0,3% na fibrose c?stica, 1,3 % na bronquiolite e 1,1% na malforma??o cong?nita. Conclus?o A dose utilizada foi significativamente menor do que a utilizada em crian?as e permitiu a visualiza??o das estruturas pulmonares em quase todos os pacientes possibilitando o diagn?stico final da fibrose c?stica, da bronquiolite e das malforma??es cong?nitas sem dificuldade de diagn?stico por artefato de imagem.
2

Desenvolvimento de t?cnica de resson?ncia nuclear magn?tica r?pida e de respira??o livre em pacientes com fibrose c?stica

Oliveira, Marinez Josefina Casarotto de 31 July 2017 (has links)
Submitted by PPG Pediatria e Sa?de da Crian?a (pediatria-pg@pucrs.br) on 2017-11-28T18:15:11Z No. of bitstreams: 1 Tese-MC.pdf: 2529108 bytes, checksum: d7557f03bd9245db7376252ca33303d0 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-12-04T12:45:28Z (GMT) No. of bitstreams: 1 Tese-MC.pdf: 2529108 bytes, checksum: d7557f03bd9245db7376252ca33303d0 (MD5) / Made available in DSpace on 2017-12-04T12:47:32Z (GMT). No. of bitstreams: 1 Tese-MC.pdf: 2529108 bytes, checksum: d7557f03bd9245db7376252ca33303d0 (MD5) Previous issue date: 2017-07-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Introduction-objective: Cystic fibrosis is the most common genetic disease in the Caucasian population. The reduction in life expectancy is due to progressive lung disease, characterized by severe changes in the pulmonary structure, more precisely, bronchiectasis and air catabolization. Computed tomography of the chest is considered the most sensitive method to monitor lung disease in cystic fibrosis. The main disadvantage is the patient's exposure to radiation. Magnetic resonance imaging of the chest, a radiation-free technique, has been introduced as an alternative to computed tomography. Magnetic resonance has been compared to computed tomography in several studies using various sequences, but none have used the combined sensing, parallel imaging, and golden-angle radial sampling technique. The aim of this study was to evaluate the combined golden-angle radial technique of magnetic resonance imaging in patients with cystic fibrosis in relation to conventional magnetic resonance imaging and computed tomography of the chest. Cystic fibrosis has been compared to computed tomography in several studies using various sequences, but none have used the combined sensing, parallel imaging, and golden-angle radial sampling technique. The aim of this study was to evaluate the combined radial-angle golden-angle technique of magnetic resonance imaging in patients with cystic fibrosis in relation to conventional magnetic resonance imaging and computed tomography of the chest. Methods: Computed tomography and magnetic resonance of the chest were performed in 29 patients with cystic fibrosis who were followed at the pediatric pulmonology outpatient clinic of the S?o Lucas Hospital of the Pontifical Catholic University of Rio Grande do Sul. The Cartesian K-space sampling and, after the free-breathing magnetic resonance techniques, using the Golden_Angle Radial Sparse Parallel technique. Magnetic resonance imaging and computed tomography of the chest were evaluated by two independent observers using the Helbich-Bhalla score. Intraclass correlation coefficient and Bland-Altman analysis were used to assess agreement and reproducibility in the Helbich-Bhalla severity score. No patient was sedated or used contrast medium. Results: Intraclass correlation coefficients and the Bland-Altman graphical model between the Helbich-Bhalla scores and the evaluated methods, computed tomography, magnetic resonance and free breating magnetic resonance , showed very strong correlations in all comparisons of the total scores (ICCCT -RM = 97%, ICCCT-FB-RM = 96% and ICCCT-FB-RM = 99%). The association of the Helbich-Bhalla score of both computed tomography and magnetic resonance with pulmonary function tests were significant, mainly in relation to the severity of bronchiectasis and thickening of the bronchial walls. Conclusion: This study demonstrated that the new technique of free-breathing magnetic resonance and combination of compressed sensing, parallel imaging and radial golden-angle sampling, showed a good concordance with computed tomography in the assessment of pulmonary alterations in cystic fibrosis. The combined golden-angle radial technique can be used in clinical practice to monitor fibrocystic lung disease, and demonstrates particular value for patients who can not hold their breath during the examination. / Introdu??o-objetivo: Fibrose c?stica ? a doen?a gen?tica mais comum na popula??o caucasiana. A redu??o da expectativa de vida ? devido ? doen?a pulmonar progressiva, caracterizada por mudan?as severas na estrutura pulmonar, mais precisamente, bronquiectasias e alcaponamento de ar. A tomografia computadorizada de t?rax ? considerada o m?todo mais sens?vel para monitorar a doen?a pulmonar na fibrose c?stica. A principal desvantagem ? a exposi??o do paciente ? radia??o. A resson?ncia magn?tica de t?rax, t?cnica livre de radia??o, tem sido introduzida como uma alternativa ? tomografia computadorizada. A resson?ncia magn?tica tem sido comparada ? tomografia computadorizada em v?rios estudos usando v?rias sequ?ncias, mas, nenhuma utilizou a t?cnica de sensoriamento comprimido, imagem paralela e amostragem golden-angle radial combinada. O objetivo deste estudo foi avaliar a t?cnica de golden-angle radial combinada de resson?ncia magn?tica de t?rax em pacientes com fibrose c?stica em rela??o ? tomografia computadorizada e a resson?ncia magn?tica convencional de t?rax. M?todos: Foram realizados exames de tomografia computadorizada e resson?ncia magn?tica de t?rax em 29 pacientes com fibrose c?stica que eram acompanhados no ambulat?rio de pneumologia pedi?trica do Hospital S?o Lucas da Pontif?cia Universidade Cat?lica do Rio Grande do Sul. Os exames, foram realizados utilizando, primeiro, a amostragem de K-espa?o cartesiano e, ap?s, as t?cnicas de resson?ncia magn?tica com respira??o livre, utilizando a t?cnica Golden_Angle Radial Sparse Parallel. As imagens de resson?ncia magn?tica e tomografia computadorizada de t?rax foram avaliadas por dois observadores independentes utilizando o escore de Helbich-Bhalla. Coeficiente de correla??o intraclasse e an?lise de Bland-Altman foram usados para avaliar a concord?ncia e a reprodutibilidade no escore de severidade de Helbich-Bhalla. Nenhum paciente foi sedado ou usado meio de contraste. Resultados: Os coeficientes de correla??o intraclasse e o modelo gr?fico de Bland-Altman entre os escores de Helbich-Bhalla e os m?todos avaliados, tomografia computadorizada, resson?ncia magn?tica e resson?ncia magn?tica de respira??o livre, evidenciaram, em todas as compara??es dos escores totais, correla??es muito fortes (ICCCT-RM = 97%; ICCCT-FB-RM = 96% e ICCCT- FB-RM=99%). A associa??o do escore de Helbich-Bhalla, tanto da tomografia computadorizada como das imagens de resson?ncia magn?tica, com os testes de fun??o pulmonar foram significativas, principalmente, em rela??o ? severidade das bronquiectasias e espessamento das paredes br?nquicas. Conclus?o: Este estudo demonstrou que a nova t?cnica de resson?ncia magn?tica com respira??o livre e combina??o de sensoriamento comprimido, imagem paralela e amostragem golden-angle radial, mostrou uma boa concord?ncia com a tomografia computadorizada na avalia??o das altera??es pulmonares na fibrose c?stica. A t?cnica de golden-angle radial combinada pode ser utilizada na pr?tica cl?nica para acompanhamento de doen?a pulmonar fibroc?stica, e demonstra particular valor para os pacientes que n?o conseguem suspender a respira??o durante o exame.

Page generated in 0.1085 seconds