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| Author(s): |
Rodrigo Sartorelo Salemi Viana
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Pesquisas Energéticas e Nucleares (IPEN/BT) |
| Defense date: | 2014-03-28 |
| Examining board members: |
Adimir dos Santos;
Claudio Antonio Federico;
Joel Mesa Hormaza;
Fabiano Carlos Paixão;
Lorena Pozzo
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| Advisor: | Adimir dos Santos; Hélio Yoriyaz |
| Abstract | |
The NSECT figures as a new spectrographic technique able to evaluate in vivo the concentration of elements using the inelastic scattering reaction (n,n). Since its introduction, several improvements have been proposed with the aim of investigating applications for clinical diagnosis and reduction of absorbed dose associated with CT acquisition. In this context, two new diagnostic applications are presented using spectroscopic and tomographic approaches from NSECT. A new methodology has also been proposed to optimize the sinogram sampling that is directly related to the quality of the reconstruction by the irradiation protocol. The studies were developed based on simulations with MCNP5 code. Diagnosis of Renal Cell Carcinoma (RCC) and the detection of breast microcalcifications were evaluated in studies conducted using a human phantom. The obtained results demonstrate the ability of the NSECT technique to detect changes in the composition of the modeled tissues as a function of the development of evaluated pathologies. The proposed method for optimizing sinograms was able to analytically simulate the composition of the irradiated medium allowing the assessment of quality of reconstruction and effective dose in terms of the sampling rate. However, future research must be conducted to quantify the sensitivity of detection according to the selected elements. (AU) | |
| FAPESP's process: | 10/04206-4 - Spectrometry and reconstruction of neutron stimulated emission computed tomography images via the EM algorithm and Monte Carlo Method |
| Grantee: | Rodrigo Sartorelo Salemi Viana |
| Support Opportunities: | Scholarships in Brazil - Doctorate |