Stimulated-Echo Single-Point Imaging (STE-SPI)
- UNB MRI Centre, University of New Brunswick, Physics, Fredericton, Canada
Single point imaging (SPI) [1] is a constant-time, purely phase-encoded measurement method, which has the dual advantages of short encoding time (allowing the visualization of short T2* species) and immunity to the geometrical distortions caused by time-dependent contributions to the point-spread function (e.g. chemical shift, magnetic susceptibility) [2,3]. Successful variations on the SPI theme have included SPRITE [4] and spin-echo SPI [5], the latter having a minimum echo time determined by gradient switching [6].
We present a stimulated-echo version of SPI, which can achieve shorter minimum echo times (as low as 100 microseconds) than its spin-echo counterpart. STE-SPI is demonstrated in a variety of porous media, where the typical T1 > T2 situation indicates the use of stimulated echoes.
[1] Emid & Creyghton, Physica B 128B 81-83 (1985).
[2] Gravina & Cory, J. Magn. Reson. B 104 53-61 (1994).
[3] Webb, Concepts in Magn. Reson. A 22A(1) 25-36 (2004).
[4] Balcom et. al. J. Magn. Reson. A 123 131-134 (1996).
[5] Ouriadov et al. J. Magn. Reson. 169 174-186 (2004).
[6] Vashaee et al. Meas. Sci. Technol. 26 055601 (16 pp.) (2015).