  T2 weighted imaging of the spine is commonly performed using fast spin echo
(FSE/TSE) based sequences, resulting in long scan times and vulnerability to
motion artifacts. While single shot fast spin echo sequences have been
attempted, their adoption has been limited by poor spatial resolution and
specific absorption rate (SAR) limitations. We investigate the use of a
half-Fourier acquisition single-shot turbo spin-echo variable flip angle
(HASTE-VFA) sequence for T2 weighted spine imaging. A variable refocusing flip
angle echo train was first optimized for the spine to improve the point spread
function (PSF) and minimize SAR, yielding images with improved spatial
resolution and signal-to-noise ratio compared to the constant flip angle
sequence. Data was acquired from 29 patients (20 lumbar and thoracolumbar, 9
whole-spine) using conventional fast spin echo and the proposed variable flip
angle single-shot sequences. All images were graded by two experienced
neuroradiologists in a blinded fashion and scores were assigned based on
blurring, motion, artifacts, and noise as well as appearance of disks, facet
joints, end plates, nerve roots and the spinal cord.
