Perfusion MRI quantification for Multi-Echo EPIK sequence in brain tumour patients
Autor(a) principal: | |
---|---|
Data de Publicação: | 2018 |
Tipo de documento: | Dissertação |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10451/36815 |
Resumo: | Tese de mestrado integrado, Engenharia Biomédica e Biofísica (Engenharia Clínica e Instrumentação Médica) Universidade de Lisboa, Faculdade de Ciências, 2018 |
id |
RCAP_41b823152be5c02928e4a5d3447dc2f7 |
---|---|
oai_identifier_str |
oai:repositorio.ul.pt:10451/36815 |
network_acronym_str |
RCAP |
network_name_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository_id_str |
7160 |
spelling |
Perfusion MRI quantification for Multi-Echo EPIK sequence in brain tumour patientsMR-PETRessonância Magnética de PerfusãoGESE-EPIKDSCDCETeses de mestrado - 2018Departamento de FísicaTese de mestrado integrado, Engenharia Biomédica e Biofísica (Engenharia Clínica e Instrumentação Médica) Universidade de Lisboa, Faculdade de Ciências, 2018The main goal of this thesis was to obtain fully quantifying perfusion parameters from both DSC (Dy-namic Susceptibility Contrast) and DCE (Dynamic Contrast Enhancement) techniques through usage of only one perfusion sequence–GESEEPIK (Gradient-echo, Spin-echo Echo-Planar Imaging with Key- hole). For this, twenty-two patients with a possible brain tumor were recruited for this study, and each patient was scanned data hybrid PET-MR 3T scanner. Firstly, T1-mapping data was acquired through a sequence of Inversion-Recovery EPIK. The contrast agent was then injected into the patient and perfusion images were acquired using the GESE EPIK sequence. Simultaneously, 18F-FET images were acquired which allowed the exclusion of patients who did not have any brain tumor. After the images were acquired, they were analyzed and the parameters were calculated. For starters, the information regarding the changes in T2 and T2*, already inherent to the data acquired, was analyzed. The curve of the MR signal was converted to the concentration curve. This curve was calculated using two different equations. With the calculated concentration curve, the DSC parameters were calculated. As expected, in areas affected by a tumor, there was an increase in vascularization due to angiogenesis. It was also observed, by comparison of the two methods used to calculate the concentration curves, that the non-removal of the leakage effects induced an unreal increase in the calculated parameters. In order to obtain images related to variations of T1 for DCE quantification, the images acquired were extrapolated to a echo time equal to zero. To these extrapolated images, the values obtained from the T1-mapping prior to the contrast’s injection were subtracted in order to obtain the concentration curve. A method that used the extrapolated images to obtain an initial T1-mapping was also tested, in order to avoid the need to implement the extra sequence for that purpose. The tofts kinetic model was applied in both methods, allowing the calculation of DCE parameters. In both applied methods, the results obtained were very similar, indicating the possibility of non-acquisition of the extra sequence if there are time constraints. However, not all parameters behaved as expected and a more detailed investigation of the literature was carried out. It is concluded that some parameters do not have a clear description and cannot characterize human physiology and be used in the study of pathologies. In conclusion, the initial goal of this thesis to obtain quantitative parameters DSC and DCE perfusion techniques, using only a single contrast sequence, was achieved with success. The need to remove leak age effects, which increased the calculated values and the tumor area, was also verified. However, some inconsistencies in the parameters’ interpretation were registered in the available literature. These inconsistencies had repercussions in some values obtained, whose interpretation was impossible, despite being in agreement with the literature. In addition, a method has been tested which further eliminates the need to acquireT1-mapping data prior to the contrast’s injection through an addition al sequence. Although not an objective of this thesis, It was not possible to relate the perfusion parameters to the degree of tumor severity.Matela, Nuno Miguel de Pinto Lobo e, 1978-Yun, Seong DaeRepositório da Universidade de LisboaSilva, Filipa Soares da2019-02-04T12:13:16Z201820182018-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfhttp://hdl.handle.net/10451/36815TID:202185621enginfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-11-08T16:33:37Zoai:repositorio.ul.pt:10451/36815Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T21:50:59.756058Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Perfusion MRI quantification for Multi-Echo EPIK sequence in brain tumour patients |
title |
Perfusion MRI quantification for Multi-Echo EPIK sequence in brain tumour patients |
spellingShingle |
Perfusion MRI quantification for Multi-Echo EPIK sequence in brain tumour patients Silva, Filipa Soares da MR-PET Ressonância Magnética de Perfusão GESE-EPIK DSC DCE Teses de mestrado - 2018 Departamento de Física |
title_short |
Perfusion MRI quantification for Multi-Echo EPIK sequence in brain tumour patients |
title_full |
Perfusion MRI quantification for Multi-Echo EPIK sequence in brain tumour patients |
title_fullStr |
Perfusion MRI quantification for Multi-Echo EPIK sequence in brain tumour patients |
title_full_unstemmed |
Perfusion MRI quantification for Multi-Echo EPIK sequence in brain tumour patients |
title_sort |
Perfusion MRI quantification for Multi-Echo EPIK sequence in brain tumour patients |
author |
Silva, Filipa Soares da |
author_facet |
Silva, Filipa Soares da |
author_role |
author |
dc.contributor.none.fl_str_mv |
Matela, Nuno Miguel de Pinto Lobo e, 1978- Yun, Seong Dae Repositório da Universidade de Lisboa |
dc.contributor.author.fl_str_mv |
Silva, Filipa Soares da |
dc.subject.por.fl_str_mv |
MR-PET Ressonância Magnética de Perfusão GESE-EPIK DSC DCE Teses de mestrado - 2018 Departamento de Física |
topic |
MR-PET Ressonância Magnética de Perfusão GESE-EPIK DSC DCE Teses de mestrado - 2018 Departamento de Física |
description |
Tese de mestrado integrado, Engenharia Biomédica e Biofísica (Engenharia Clínica e Instrumentação Médica) Universidade de Lisboa, Faculdade de Ciências, 2018 |
publishDate |
2018 |
dc.date.none.fl_str_mv |
2018 2018 2018-01-01T00:00:00Z 2019-02-04T12:13:16Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10451/36815 TID:202185621 |
url |
http://hdl.handle.net/10451/36815 |
identifier_str_mv |
TID:202185621 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
instname_str |
Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
repository.mail.fl_str_mv |
|
_version_ |
1799134444865454080 |