Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Adaptive motion mapping in pancreatic SBRT patients using Fourier
  transforms   Recent studies suggest that 4DCT is unable to accurately measure
respiratory-induced pancreatic tumor motion. In this work, we assessed the
daily motion of pancreatic tumors treated with SBRT, and developed adaptive
strategies to predict and account for this motion. The daily motion trajectory
of pancreatic tumors during CBCT acquisition was calculated using a model which
reconstructs the instantaneous 3D position in each 2D CBCT projection image. We
developed a metric (termed "Spectral Coherence," SC) based on the Fourier
frequency spectrum of motion in the SI direction, and analyzed the ability of
SC to predict motion-based errors and classify patients according to motion
characteristics. The amplitude of daily motion exceeded the predictions of
pre-treatment 4DCT imaging by an average of 3.0 mm, 2.3 mm, and 3.5 mm in the
AP, LR, and SI directions. SC was correlated with daily motion differences and
tumor dose coverage. In a simulated adaptive protocol, target margins were
adjusted based on SC, resulting in significant increases in mean target D95,
D99, and minimum dose. Our Fourier-based approach differentiates between
consistent and inconsistent motion characteristics of respiration and
correlates with daily motion deviations from pre-treatment 4DCT. The
feasibility of an SC-based adaptive protocol was demonstrated, and this
patient-specific respiratory information was used to improve target dosimetry
by expanding coverage in inconsistent breathers while shrinking treatment
volumes in consistent breathers.

34
The categories of this paper are: chem-ph
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex
6
The categories of this paper are: astro-ph
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
21
The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph