Estudo comparativo da qualidade de imagem dos modos de aquisição da PET: validação de um protocolo para reduzir a dose de radiação

• Autor(a) principal: Nogueira, Solange Amorim
• Data de Publicação: 2009
• Outros Autores: Lederman, Henrique Manoel [UNIFESP], Wagner, Jairo, Yamaga, Lilian Yuri, Cunha, Marcelo Livorsi Da, Funari, Marcelo Buarque De Gusmão
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Repositório Institucional da UNIFESP
• Texto Completo: http://dx.doi.org/10.1590/S0100-39842009000200008; http://repositorio.unifesp.br/handle/11600/4988
• topic: PET/CT; Imaging quality; 2D mode; 3D mode; 18F-FDG; Dose reduction; PET/CT; Qualidade da imagem; Modo 2D; Modo 3D; FDG-18F; Redução de dose

OBJECTIVE: The present study is aimed at validating a 3D acquisition protocol for positron emission tomography as a replacement for the 2D mode, to reduce the radiation dose delivered to patients, without any loss in the quality of images. MATERIALS AND METHODS: The study comprised 27 simulations in a Discovery ST equipment with four-minute 2D acquisitions, and two-minute and four-minute 3D acquisitions, utilizing a chest phantom according to the National Electrical Manufacturers Association protocol. Six spheres with different diameters were inserted into this phantom as a means for determining the images quality. The images were blindly reviewed by three experienced nuclear physicians who did not know the acquisition modes. Each observer attributed a score 1 when one of the spheres was not identified, or 2 for visible spheres. RESULTS: The qualitative analysis based on generalized kappa coefficient demonstrated that the frequency of visible spheres was higher with four-minute 3D acquisitions (85%), with an also higher interobserver agreement (88.9%), generalized kappa = 0.725 [0.507;0.942]. CONCLUSION: The protocol with four-minute 3D acquisition with lower 18F-FDG activity can be utilized for patients with a biotype similar to the phantom, without any loss in the imaging quality.