ABSTRACT
PURPOSE: To evaluate the diagnostic performance of free breathing three-dimensional gradient echo-sequence with radial data sampling (radial 3D-GRE) in MR imaging of the normal and diseased pancreas, using standard 3D-GRE for comparison in cooperative patients, and to perform a preliminary assessment in noncooperative patients. MATERIALS AND METHODS: One hundred and eight consecutive patients underwent 1.5 Tesla MR imaging of the abdomen that included pre- and postcontrast free breathing radial 3D-GRE. The sequences were evaluated by two radiologists retrospectively, independently, and blindly. The results were compared using Wilcoxon-Mann-Whitney test. Kappa statistics were used to measure the extent of agreement between the reviewers. RESULTS: The average scores indicated that the overall images quality of radial 3D-GRE was lower than 3D-GRE-VIBE in both pre- and postcontrast study (P = 0.0172 and 0.0001), however it achieved a rating that approximated good. In all patients, radial 3D-GRE had a mild extent of streak artifact, pulsation, susceptibility, and respiratory artifact. Radial 3D-GRE approximated good results for pancreatic edge sharpness and pancreatic ductal clarity, and did not differ significantly between cooperative and noncooperative patients. Respiratory artifact was worse in cooperative than in noncooperative patients (P = 0.02). Demonstration of pancreatic disease was slightly inferior with radial 3D-VIBE, but quality approximated good. CONCLUSION: Free breathing radial 3D-GRE may be applicable for pancreatic MR imaging in patients who are unable to suspend respiration.
Subject(s)
Breath Holding , Echo-Planar Imaging/methods , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Pancreas/pathology , Pancreatic Diseases/pathology , Algorithms , Female , Humans , Male , Middle Aged , Reproducibility of Results , Sample Size , Sensitivity and SpecificityABSTRACT
OBJECTIVE: To evaluate a comprehensive MRI protocol that investigates for cancer, vascular disease, and degenerative/inflammatory disease from the head to the pelvis in less than 40 minutes on a new generation 48-channel 3T system. MATERIALS AND METHODS: All MR studies were performed on a 48-channel 3T MR scanner. A 20-channel head/neck coil, two 18-channel body arrays, and a 32-channel spine array were employed. A total of 4 healthy individuals were studied. The designed protocol included a combination of single-shot T2-weighted sequences, T1-weighted 3D gradient-echo pre- and post-gadolinium. All images were retrospectively evaluated by two radiologists independently for overall image quality. RESULTS: The image quality for cancer was rated as excellent in the liver, pancreas, kidneys, lungs, pelvic organs, and brain, and rated as fair in the colon and breast. For vascular diseases ratings were excellent in the aorta, major branch vessel origins, inferior vena cava, portal and hepatic veins, rated as good in pulmonary arteries, and as poor in the coronary arteries. For degenerative/inflammatory diseases ratings were excellent in the brain, liver and pancreas. The inter-observer agreement was excellent. CONCLUSION: A comprehensive and time efficient screening for important categories of disease processes may be achieved with high quality imaging in a new generation 48-channel 3T system.
OBJETIVO: Avaliar protocolo de RM para investigação de neoplasia, doenças vascular e degenerativa/inflamatória da cabeça à pelve em menos de 40 minutos em equipamento 3T com 48 canais. MATERIAIS E MÉTODOS: Todos os exames foram realizados em equipamento 3T com 48 canais. Foram utilizadas bobinas de cabeça/pescoço (20 canais), duas de corpo interligadas (18 canais) e uma de coluna (32 canais). Quatro voluntários saudáveis foram estudados. Foi utilizado protocolo com sequências single shot pesadas em T2 e gradiente-eco 3D pesadas em T1 pré e pós-gadolínio. Todas as imagens foram avaliadas quanto à qualidade, retrospectivamente, por dois radiologistas de forma independente. RESULTADOS: A qualidade da imagem foi classificada como excelente para o fígado, pâncreas, rins, pulmões, órgãos pélvicos e encéfalo, e como adequada para cólon e mamas. Para as doenças vasculares as imagens foram classificadas como excelentes para aorta e seus ramos principais, veia cava inferior, veias porta e hepáticas, como boas para artérias pulmonares, e como inadequadas para coronárias. As classificações para doenças degenerativas/inflamatórias foram excelente no encéfalo, fígado e pâncreas. A concordância interobservador foi excelente. CONCLUSÃO: Um rastreamento abrangente de importantes categorias de doenças pode ser realizado utilizando imagens de alta qualidade obtidas em uma nova geração de equipamento 3T com 48 canais.
