A multicontrast imaging method using steady-state free precession with alternating RF flip angles.

Abstract

To obtain multicontrast images including fat-suppressed contrast image, a novel multicontrast imaging method using an SSFP sequence with alternating RF flip angles is proposed. The proposed method uses the balanced SSFP sequence with 2 flip angles. In general, the conventional balanced SSFP sequence has its own unique contrast, which combines both FID signal and echo signal under a steady-state condition. By using alternating RF flip angles and RF phase cycling, various image contrasts weighted by proton density, T1 , and T2 can be obtained. The proposed method offers multicontrast images with fat suppression by using the combination of 2 images obtained just after alternating RF pulses, respectively. As demonstrated by simulations, phantom and in vivo experiments, the proposed method provides multicontrast knee images including fat-suppressed contrast images. The proposed method can be a useful tool for clinical diagnosis, such as the cartilage segmentation and the fast screening of lesions.