Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Slice-selective Zero Echo Time imaging of ultra-short T2 tissues based
  on spin-locking   Purpose: To expand the capabilities of Zero Echo Time (ZTE) pulse sequences
with a slice selection method suitable for the shortest-lived tissues in the
body.
  Methods: We introduce two new sequences that integrate spin-locking pulses
into standard ZTE imaging to achieve slice selection: one for moderately short
$T_2$ (DiSLoP), the other for ultra-short $T_2$ samples (PreSLoP). These
methods exploit the slower signal decay (at $T_{1\rho}\gg T_2$) to retain the
magnetization in the slices during the selection process, which is otherwise
comparable to or even much longer than $T_2$.
  Results: We demonstrate control over the slice profiles and positions for 2D
imaging. We measure magnetization decay times during spin-locking ($T_{1\rho}$)
as a function of pulse amplitude, showing significant lifetime enhancement for
amplitudes as low as 10 uT. We show imaging of slice-selected samples with
$T_2$ characteristic times in the range of single milliseconds with DiSLoP and
PreSLoP, and with the latter for sub-millisecond $T_2$ tissues. As compared to
standard 3D ZTE sequences, PreSLoP achieves the same signal-to-noise ratio
(SNR) in 2-5 times shorter scan times, and we argue that this is due to the
filling scheme of the finite gap at the center of $k$-space unavoidable with
ZTE sequences. Finally, we discuss a combination of DiSLoP with a dynamical
decoupling sequence to avoid this central gap, leading to further scan time
accelerations.
  Conclusions: The proposed sequences are capable of slice-selected 2D imaging
of tissues with $T_2$ as low as 275 us with good SNR within clinically
acceptable scan times.

9
The categories of this paper are: nlin
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
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The categories of this paper are: comp-gas