Reduced field-of-view single-shot fast spin echo imaging using two-dimensional spatially selective radiofrequency pulses.
OBJECTIVE
To demonstrate reduced field-of-view (RFOV) single-shot fast spin echo (SS-FSE) imaging based on the use of two-dimensional spatially selective radiofrequency (2DRF) pulses.


METHODS
The 2DRF pulses were incorporated into an SS-FSE sequence for RFOV imaging in both phantoms and the human brain on a 1.5 Tesla (T) whole-body MR system with the aim of demonstrating improvements in terms of shorter scan time, reduced blurring, and higher spatial resolution compared with full FOV imaging.


RESULTS
For phantom studies, scan time gains of up to 4.2-fold were achieved as compared to the full FOV imaging. For human studies, the spatial resolution was increased by a factor of 2.5 (from 1.7 mm/pixel to 0.69 mm/pixel) for RFOV imaging within a scan time (0.7 s) similar to full FOV imaging. A 2.2-fold shorter scan time along with a significant reduction of blurring was demonstrated in RFOV images compared with full FOV images for a target spatial resolution of 0.69 mm/pixel.


CONCLUSIONS
RFOV SS-FSE imaging using a 2DRF pulse shows advantages in scan time, blurring, and specific absorption rate reduction along with true spatial resolution increase compared with full FOV imaging. This approach is promising to benefit fast imaging applications such as image guided therapy.
Yuan
Jing
J
Department of Diagnostic Radiology and Organ Imaging, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China. jyuan@cuhk.edu.hk
Zhao
Tzu-Cheng
TC
Tang
Yi
Y
Panych
Lawrence P
LP
D001921:Brain / Q000033:anatomy & histology*; D001931:Brain Mapping / Q000379:methods; D017352:Echo-Planar Imaging / Q000379:methods*; D006801:Humans; D019047:Phantoms, Imaging; D012016:Reference Values