ABSTRACT
BACKGROUND: The use of positron emission tomography combined with computed tomography (PET/CT) has brought about significant technological advancement in diagnostic imaging, and a number of PET/CT scanners with bismuth germanate detectors can perform imaging in both 2D and 3D acquisition modes. Nevertheless, certain image acquisition parameters and physical features of patients have to be considered when designing low-dose protocols in the 3D mode. PURPOSE: The aim of this study was to compare images acquired in 2D and 3D modes and establish a low-dose protocol for use in PET/CT imaging, decreasing patient exposure to radiation without compromising results. METHODS: A total of 30 patients, aged 4-72 years, participated in this prospective study, which was conducted at Albert Einstein Hospital, São Paulo, Brazil. Images were evaluated for picture quality, presence/absence of lesions and the number of lesions that were detectable in both acquisition modes. RESULTS: The results consistently showed that the loss in image quality in the 3D mode did not affect exam interpretation and lesion detection when compared with 2D at higher dose and for a longer time. CONCLUSIONS: We therefore conclude that administration of 3.7 MBq [(18)F]-fluorodeoxyglucose (FDG)/kg for an acquisition time of 3 min per FOV (field of view) is optimal for image acquisition in the 3D mode. This protocol, which reduces the acquisition time and radiation dose, is quite beneficial, especially for children.
Subject(s)
Bismuth , Germanium , Imaging, Three-Dimensional , Positron-Emission Tomography , Radiation Dosage , Tomography, X-Ray Computed , Adolescent , Adult , Aged , Child , Child, Preschool , Clinical Protocols , Humans , Middle Aged , Prospective Studies , Young AdultABSTRACT
pOBJETIVO: Avaliar o impacto das ações de vigilância sanitária sobre a qualidade das imagens mamográficas no Estado da Paraíba. MATERIAIS E MÉTODOS: Em 17 serviços de mamografia do Estado foi exigida pela Vigilância Sanitária a aplicação de testes de qualidade de acordo com a Portaria 453/98 do Ministério da Saúde. Foram utilizados simuladores específicos de mama para a avaliação da qualidade. Uma pontuação foi utilizada para classificar a qualidade de imagem de cada serviço. Considerou-se como critério mínimo e imprescindível o atendimento de uma pontuação 70 por cento dos itens de qualidade. Entre os anos de 1999 e 2003 foi analisada a pontuação de qualidade de imagens desses serviços. Foi realizado um programa de educação de controle de qualidade de imagem pela Vigilância Sanitária da Paraíba. RESULTADOS: Os percentuais de serviços de mamografia que atingiram critério imprescindível de qualidade foram: 1999 (25 por cento), 2000 (77 por cento), 2001 (82 por cento) e 2003 (81 por cento). CONCLUSÃO: Os resultados obtidos demonstram haver uma significativa evolução na qualidade das imagens diagnósticas produzidas pelos serviços de mamografia após a implantação de programas de controle de qualidade da imagem.
OBJECTIVE: To evaluate the impact of health surveillance actions on the quality of mammographic images in the Paraíba State, Brazil. MATERIALS AND METHODS: Seventeen mammography services were required by the Health Surveillance Agency to apply quality tests according to the Ministry of Health Ordinance no. 453/98. Specifically designed breast phantoms were utilized for quality assessment. Each service was given a score corresponding to the images quality. The achievement of a minimum rating level of 70 percent for quality items was considered as fundamental. Scores for images quality in these services were analyzed in the period from 1999 to 2003. RESULTS: The percentages of mammographic centers that met the essential quality criterion were: 1999 (25 percent), 2000 (77 percent), 2001 (82 percent), 2002 (77 percent) and 2003 (81 percent). CONCLUSION: The obtained results demonstrate a significant progress in the quality of diagnostic images produced by the mammography services after the implementation of images quality control programs.
