2017 JRNL PP Amir Alansary, - 1.pdf)u
Terbatas  Irwan Sofiyan
» Gedung UPT Perpustakaan
Terbatas  Irwan Sofiyan
» Gedung UPT Perpustakaan
In this paper, we present a novel method
for the correction of motion artifacts that are present
in fetal magnetic resonance imaging (MRI) scans of the
whole uterus. Contrary to current slice-to-volume registration
(SVR) methods, requiring an inflexible anatomical
enclosure of a single investigated organ, the proposed
patch-to-volume reconstruction (PVR) approach is able to
reconstruct a large field of view of non-rigidly deforming
structures. It relaxes rigid motion assumptions by
introducing a specific amount of redundant information
that is exploited with parallelized patchwise optimization,
super-resolution,and automatic outlier rejection.We further
describe and provide an efficient parallel implementation
of PVR allowing its execution within reasonable time on
commercially available graphics processing units, enabling
its use in the clinical practice. We evaluate PVR’s computational
overhead compared with standard methods and
observe improved reconstruction accuracy in the presence
of affine motion artifacts compared with conventional SVR
in synthetic experiments. Furthermore, we have evaluated
our method qualitatively and quantitatively on real fetal MRI
data subject to maternal breathing and sudden fetal movements.
We evaluate peak-signal-to-noise ratio, structural
similarity index, and cross correlation with respect to the
originally acquired data and provide a method for visual
inspection of reconstruction uncertainty. We further evaluate
the distance error for selected anatomical landmarks in
the fetal head, aswell as calculating themean andmaximum
displacements resulting from automatic non-rigid registration
to amotion-free ground truth image. These experiments
demonstrate a successful application of PVR motion compensation
to the whole fetal body, uterus, and placenta.