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| Author(s): |
Edward Florez Pacheco
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Escola Politécnica (EP/BC) |
| Defense date: | 2016-03-28 |
| Examining board members: |
Sergio Shiguemi Furuie;
Carlos Alberto Buchpiguel;
Marco Antonio Gutierrez;
Nelson Delfino d'Ávila Mascarenhas;
Mauricio Moralles
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| Advisor: | Sergio Shiguemi Furuie |
| Abstract | |
The presence of Nuclear Medicine as a medical imaging modality is one of the main procedures utilized nowadays in medical centers, and the great advantage of that procedure is its capacity to analyze the metabolic behavior of the patient, resulting in early diagnoses. However, the quantification in Nuclear Medicine is known to be complicated by many factors, such as degradations due to attenuation, scattering, reconstruction algorithms and assumed models. In this context, the goal of this project is to improve the accuracy and the precision of quantification in PET/CT images by means of realistic and well-controlled processes. For this purpose, we proposed to develop a framework, which consists in a set of consecutively interlinked steps that is initiated with the simulation of 3D anthropomorphic phantoms. These phantoms were used to generate realistic PET/CT projections by applying the GATE platform (with Monte Carlo simulation). Then a 3D image reconstruction was executed, followed by a filtering process (using the Anscombe/Wiener filter to reduce Poisson noise characteristic of this type of images) and, a segmentation process (based on the Fuzzy Connectedness theory). After defining the region of interest (ROI), input activity and output response curves are required for the compartment analysis in order to obtain the Metabolic Quantification of the selected organ or structure. Finally, in the same manner real images provided from the Heart Institute (InCor) of Hospital das Clínicas, Faculty of Medicine, University of São Paulo (HC-FMUSP) were analysed. Therefore, it is concluded that the three-dimensional filtering step using the Ascombe/Wiener filter was preponderant and had a high impact on the metabolic quantification process and on other important stages of the whole project. (AU) | |
| FAPESP's process: | 11/23172-6 - Analysis of the dynamic and metabolic quantification of nuclear medicine images in the PET/CT modality |
| Grantee: | Edward Flórez Pacheco |
| Support Opportunities: | Scholarships in Brazil - Doctorate |