Investigação dos parâmetros dependentes do paciente para a otimização da atividade administrada em exames de PET/CT com 18F-FDG

Detalhes bibliográficos
Ano de defesa: 2016
Autor(a) principal: Martini, Júlio César lattes
Orientador(a): Silva, Ana Maria Marques da lattes
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Pontifícia Universidade Católica do Rio Grande do Sul
Programa de Pós-Graduação: Programa de Pós-Graduação em Engenharia Elétrica
Departamento: Faculdade de Engenharia
País: Brasil
Palavras-chave em Português:
Área do conhecimento CNPq:
Link de acesso: http://tede2.pucrs.br/tede2/handle/tede/7074
Resumo: Despite the activities administered to patients during Positron Emission Tomography (PET) scans are guided by methods and reference levels, in clinical practice there is a great discrepancy between these values. Current indications use dependent patient parameters (DPP), such as age and weight, without considering an assessment of the resulting image quality. The purpose of this study is to investigate how the anthropometric and physiological characteristics of patients influence the determination of 18F-FDG activity to be administered in PET/CT scans and image quality. Therefore, we conducted a preliminary study with three simulators of different diameters, representing patients with different sizes, with different values of activity concentration. Subsequently, we performed a retrospective study on a PET/CT image database acquired with 18F-FDG. Image quality indicators (NECR, and NECRN and SNRnorm) of the images of patients were determined for many PDP, namely: body weight, BMI, BSA, fat mass, mass-height ratio and equivalent diameter. The relationship between the administered activity, counts rates and the PDP, with image quality indicators were statistically evaluated. We concluded that the NECRN is the quality indicator which has the best correlation between the PDP, particularly with body mass and BMI. The image quality in can be estimated from the true coincidence events rate (TRUES) during PET/CT acquisition with 18F-FDG, due to the highly linear relationship with NECR for different body mass or BMI ranges, allowing the optimization of the administered activity based on the physical characteristics of the patient.