Cardiac magnetic resonance imaging (MRI) shows great potential but requires substantial improvements in contrast, spatial resolution, and speed. Two recent advances of particular interest are the development of balanced steady state free precession (SSFP) imaging sequences (equivalently known as True-FISP, FIESTA, or Balanced-FFE), and the development and availability of 3 Telsa clinical scanners. Both provide substantial improvements in SNR and contrast but together, 3T and SSFP are relatively incompatible for rapid high-resolution cardiac imaging. Conventional SSFP is critically limited by banding artifacts that require the use of repetition times of 3 ms or less in the heart at 3T. This limits the achievable spatial resolution, and prevents the use of time-efficient acquisition schemes to reduce scan time.
The aim of this proposal is to develop and validate a new imaging technique, which we call Wideband SSFP, that uses alternating repetition times to achieve a steady-state that provides up to double the bandwidth of conventional SSFP, with comparable SNR and contrast. This bandwidth improvement allows the use of longer imaging TRs which will supporting readouts on the order of 4 ms, to enable high spatial resolution (increased readout gradient area) and high temporal resolution (using time-efficient acquisition schemes). The goal of this proposal is to fully characterize and develop Wideband SSFP and apply it to rapid high- resolution cardiac MRI at 3 Tesla. Utilizing SNR improvements from the 3T platform and from SSFP sequences to achieve higher spatial and temporal resolution directly addresses the current limitations of clinical cardiac MRI. ? ?
| Lee, Hsu-Lei; Shankaranarayanan, Ajit; Pohost, Gerald M et al. (2010) Improved 3-Tesla cardiac cine imaging using wideband. Magn Reson Med 63:1716-22 |
| Sung, Kyunghyun; Lee, Hsu-Lei; Hu, Houchun H et al. (2010) Prediction of myocardial signal during CINE balanced SSFP imaging. MAGMA 23:85-91 |
| Lee, Hsu-Lei; Shankaranarayanan, Ajit; Pohost, Gerald M et al. (2010) Improved coronary MR angiography using wideband steady state free precession at 3 tesla with sub-millimeter resolution. J Magn Reson Imaging 31:1224-9 |
| Nielsen, Jon-Fredrik; Nayak, Krishna S (2009) Referenceless phase velocity mapping using balanced SSFP. Magn Reson Med 61:1096-102 |
| Nielsen, Jon-Fredrik; Nayak, Krishna S (2009) Interleaved balanced SSFP imaging: artifact reduction using gradient waveform grouping. J Magn Reson Imaging 29:745-50 |
| Sung, Kyunghyun; Nayak, Krishna S (2008) Measurement and characterization of RF nonuniformity over the heart at 3T using body coil transmission. J Magn Reson Imaging 27:643-8 |
| Lee, Hsu-Lei; Nayak, Krishna S (2008) Stabilization of alternating TR steady-state free precession sequences. J Magn Reson 195:211-8 |
| Nielsen, Jon-Fredrik; Nayak, Krishna S (2007) SSFP and GRE phase contrast imaging using a three-echo readout. Magn Reson Med 58:1288-93 |
| Nayak, Krishna S; Lee, Hsu-Lei; Hargreaves, Brian A et al. (2007) Wideband SSFP: alternating repetition time balanced steady state free precession with increased band spacing. Magn Reson Med 58:931-8 |
| Nielsen, J-F; Nayak, K S (2006) Pulse sequences for phase-contrast SSFP imaging from a single steady-state. Proc Int Soc Magn Reson Med Sci Meet Exhib Int Soc Magn Reson M 14:879 |
