Tomografia por biosusceptometria de corrente alternada (TBAC): novas Instrumentações e caracterizações

• Ano de defesa: 2015
• Autor(a) principal: Matos, Ronaldo Vitor Reis [UNESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Tomografia; Biosusceptometria de Corrente Alternada; Instrumentos e aparelhos médicos; Processamento de imagens; Alternated Current Biosusceptometry
• Link de acesso: http://hdl.handle.net/11449/144033; http://www.athena.biblioteca.unesp.br/exlibris/bd/cathedra/24-08-2016/000868423.pdf

In recent years researchers have tried to develop techniques that are free of ionizing radiation, such as biomagnetic techniques. Of these, there is the AC biosusceptometria (BAC), which is a very simple technique, low cost and versatile which has wide application in research related to the human gastrointestinal tract and recently has been enhanced so that it could generate ferromagnetic markers pictures both in vitro and in vivo, as it was proposed a new instrumentation for the acquisition of tomographic images referred to as Alternating Current Biosusceptometria Tomography (ACBT). This project proposes the development of new instrumentation and computational resources characterizations that allow the application of BAC to produce tomographic images of phantoms in vitro. To that end, we built new image acquisition systems with samples and rotating sensors and reconstruction algorithm application (filtered back projection method) to obtain tomographic images of different phantoms by AC biosusceptometria. For planar systems there have been advances in sensitivity or 50% signal strength and spatial resolution increased from 7.4 cm to 5.7 cm, since the radius of detection and excitation has been changed from the other system previously used . Comparing the planar systems with new circular system the temporal resolution gain was significant, from 3 hours to 2 minutes which will give us future in vivo measurements, to join this gain due to the acquisition mode of the signals other problems were found as new signal processing methods as well as new reconstruction algorithms