RESUMO
BACKGROUND: Magnetic resonance imaging (MRI) has become a powerful imaging modality to quantify blood flow. To gain insight of the hemodynamics of the human cardiovascular system, acquisition time of MR images must be reduced. It is necessary to produce faster imaging methods to avoid motion artifacts, such as blurring and ghosting, which alter the image quality. To solve this problem a flow-encoded Echo-Planar Imaging (EPI) sequence combined with a Half Fourier method is proposed to determine blood flow in the cardiovascular system. METHODS: This imaging modality was used to quantify blood flow in large vessels such as the human aorta. We acquired transaxial 128x128 images, with a slice of 1-cm thickness and 2.5 mm in-plane resolution. All these images were used to measure blood flow in the ascending aorta and descending aorta of nine healthy male volunteers and one female volunteer, ages 22-35 years. RESULTS: Velocity profiles and blood flow maps were obtained from healthy volunteers and compared with other imaging techniques. CONCLUSIONS: It has been demonstrated that Half Fourier EPI flow sequence can become a suitable flow measurement technique for real-time magnetic resonance angiography. It provides us with morphological and functional information of the cardiovascular system.