This
research
focuses
on
modifying
the
Pix2Pix
model
for
purpose
of
depth
estimation,
which
involves
translating
original
images
into
RGB
images.
Depth
estimation
refers
to
process
predicting
distance
or
information
objects
in
an
image
scene.
By
incorporating
SELU
activation
function
and
employing
Alpha
Dropout
technique,
we
introduce
modifications
model.
The
experimental
results
demonstrate
that
these
lead
a
notable
reduction
discriminator
loss
by
0.09363725
decrease
generator
0.06176615
during
14th
iteration.
These
findings
indicate
significant
improvement
performance
after
applied
modifications.
The Egyptian Journal of Radiology and Nuclear Medicine,
Journal Year:
2024,
Volume and Issue:
55(1)
Published: June 11, 2024
Abstract
Background
This
research
presents
a
novel
methodology
for
synthesizing
3D
multi-contrast
MRI
images
utilizing
the
Dual-CycleGAN
architecture.
The
performance
of
model
is
evaluated
on
different
sequences,
including
T1-weighted
(T1W),
contrast-enhanced
(T1c),
T2-weighted
(T2W),
and
FLAIR
sequences.
Results
Our
approach
demonstrates
proficient
learning
capabilities
in
transforming
T1W
into
target
modalities.
proposed
framework
encompasses
combination
loss
functions
voxel-wise,
gradient
difference,
perceptual,
structural
similarity
losses.
These
components,
along
with
adversarial
dual
cycle-consistency
losses,
contribute
significantly
to
realistic
accurate
syntheses.
Evaluation
metrics
MAE,
PMAE,
RMSE,
PCC,
PSNR,
SSIM
are
employed
assess
fidelity
synthesized
compared
their
ground
truth
counterparts.
Empirical
results
indicate
effectiveness
generating
T1c
from
inputs
minimal
average
discrepancies
(MAE
2.8
±
2.61)
strong
(SSIM
0.82
0.28).
Furthermore,
synthesis
T2W
yields
promising
outcomes,
demonstrating
acceptable
3.87
3.32
3.82
FLAIR)
reasonable
similarities
0.28
0.80
0.29
relative
original
images.
Conclusions
findings
underscore
efficacy
high-fidelity
images,
significant
implications
diverse
applications
field
medical
imaging.
Frontiers in Radiology,
Journal Year:
2024,
Volume and Issue:
4
Published: March 27, 2024
The
aim
of
this
systematic
review
is
to
determine
whether
Deep
Learning
(DL)
algorithms
can
provide
a
clinically
feasible
alternative
classic
for
synthetic
Computer
Tomography
(sCT).
following
categories
are
presented
in
study:
∙
MR-based
treatment
planning
and
CT
generation
techniques.
id="IM2">∙
Generation
images
based
on
Cone
Beam
images.
id="IM3">∙
Low-dose
High-dose
generation.
id="IM4">∙
Attenuation
correction
PET
To
perform
appropriate
database
searches,
we
reviewed
journal
articles
published
between
January
2018
June
2023.
Current
methodology,
study
strategies,
results
with
relevant
clinical
applications
were
analyzed
as
outlined
the
state-of-the-art
deep
learning
approaches
inter-modality
intra-modality
image
synthesis.
This
was
accomplished
by
contrasting
provided
methodologies
traditional
research
approaches.
key
contributions
each
category
highlighted,
specific
challenges
identified,
accomplishments
summarized.
As
final
step,
statistics
all
cited
works
from
various
aspects
analyzed,
which
revealed
that
DL-based
sCTs
have
achieved
considerable
popularity,
while
also
showing
potential
technology.
In
order
assess
readiness
methods,
examined
current
status
sCT
Physics in Medicine and Biology,
Journal Year:
2023,
Volume and Issue:
68(19), P. 195003 - 195003
Published: Aug. 11, 2023
Abstract
Objective
.
In
MR-only
clinical
workflow,
replacing
CT
with
MR
image
is
of
advantage
for
workflow
efficiency
and
reduces
radiation
to
the
patient.
An
important
step
required
eliminate
scan
from
generate
information
provided
by
via
an
image.
this
work,
we
aim
demonstrate
a
method
accurate
synthetic
(sCT)
suit
therapy
(RT)
treatment
planning
workflow.
We
show
feasibility
make
way
broader
evaluation.
Approach
present
machine
learning
sCT
generation
zero-echo-time
(ZTE)
MRI
aimed
at
structural
quantitative
accuracies
image,
particular
focus
on
bone
density
value
prediction.
The
misestimation
in
path
could
lead
unintended
dose
delivery
target
volume
results
suboptimal
outcome.
propose
loss
function
that
favors
spatially
sparse
region
harness
ability
multi-task
network
produce
correlated
outputs
as
framework
enable
localization
interest
(RoI)
segmentation,
emphasize
regression
values
within
RoI
still
retain
overall
accuracy
global
regression.
optimized
composite
combines
dedicated
each
task.
Main
have
included
54
brain
patient
images
study
tested
against
reference
subset
20
cases.
A
pilot
evaluation
was
performed
9
test
cases
viability
generated
RT
planning.
average
metrics
produced
proposed
over
set
were—(a)
mean
absolute
error
(MAE)
70
±
8.6
HU;
(b)
peak
signal-to-noise
ratio
(PSNR)
29.4
2.8
dB;
similarity
metric
(SSIM)
0.95
0.02;
(d)
Dice
coefficient
body
0.984
0.
Significance
generates
resemble
visual
characteristics
real
has
suits
application.
compare
calculation
setup
based
falls
0.5%
error.
presented
here
initial
makes
encouraging
precursor
different
anatomical
regions.
Physics and Imaging in Radiation Oncology,
Journal Year:
2023,
Volume and Issue:
28, P. 100511 - 100511
Published: Oct. 1, 2023
Background
and
Purpose:
Addressing
the
need
for
accurate
dose
calculation
in
MRI-only
radiotherapy,
generation
of
synthetic
Computed
Tomography
(sCT)
from
MRI
has
emerged.
Deep
learning
(DL)
techniques,
have
shown
promising
results
achieving
high
sCT
accuracies.
However,
existing
synthesis
methods
are
often
center-specific,
posing
a
challenge
to
their
generalizability.
To
overcome
this
limitation,
recent
studies
proposed
approaches,
such
as
multicenter
training
.
Material
methods:
The
purpose
work
was
propose
by
DL,
using
2D
cycle-GAN
on
128
prostate
cancer
patients,
four
different
centers.
Four
cases
were
compared:
monocenter
cases,
test
another
center,
trainings
center
not
included
with
an
test.
Trainings
performed
20
patients.
accuracy
evaluation
Mean
Absolute
Error,
Error
Peak-Signal-to-Noise-Ratio.
Dose
assessed
gamma
index
Volume
Histogram
comparison.
Results:
Qualitative,
quantitative
show
that
sCTs
seen
did
differ
significantly.
when
involved
unseen
quality
inferior.
Conclusions:
aim
generalizable
MR-to-CT
synthesis.
It
only
few
data
one
cohort
allows
equivalent
study.
Radiation Oncology,
Journal Year:
2025,
Volume and Issue:
20(1)
Published: Feb. 4, 2025
Abstract
Rationale
and
objectives
This
study
evaluated
StarGAN,
a
deep
learning
model
designed
to
generate
synthetic
computed
tomography
(sCT)
images
from
magnetic
resonance
imaging
(MRI)
cone-beam
(CBCT)
data
using
single
model.
The
goal
was
provide
accurate
Hounsfield
unit
(HU)
for
dose
calculation
enable
MRI
simulation
adaptive
radiation
therapy
(ART)
CBCT
or
MRI.
We
also
compared
the
performance
benefits
of
StarGAN
commonly
used
CycleGAN.
Materials
methods
CycleGAN
were
employed
in
this
study.
dataset
comprised
53
cases
pelvic
cancer.
Evaluation
involved
qualitative
quantitative
analyses,
focusing
on
image
quality
distribution
calculation.
Results
For
sCT
generated
CBCT,
demonstrated
superior
anatomical
preservation
based
evaluation.
Quantitatively,
exhibited
lower
mean
absolute
error
(MAE)
body
(42.8
±
4.3
HU)
bone
(138.2
20.3),
whereas
produced
higher
MAE
(50.8
5.2
(153.4
27.7
HU).
Dosimetric
evaluation
showed
difference
(DD)
within
2%
planning
target
volume
(PTV)
body,
with
gamma
passing
rate
(GPR)
>
90%
under
2%/2
mm
criteria.
MRI,
favored
provided
by
StarGAN.
recorded
(79.8
14
HU
253.6
30.9
bone)
(94.7
7.4
353.6
34.9
bone).
Both
models
achieved
DD
PTV
GPR
90%.
Conclusion
While
metrics,
better
preservation,
highlighting
its
potential
generation
radiotherapy.
Frontiers in Oncology,
Journal Year:
2023,
Volume and Issue:
13
Published: Nov. 28, 2023
Introduction
For
radiotherapy
based
solely
on
magnetic
resonance
imaging
(MRI),
generating
synthetic
computed
tomography
scans
(sCT)
from
MRI
is
essential
for
dose
calculation.
The
use
of
deep
learning
(DL)
methods
to
generate
sCT
has
shown
encouraging
results
if
the
images
used
training
network
and
generation
come
same
device.
objective
this
study
was
create
evaluate
a
generic
DL
model
capable
sCTs
various
devices
prostate
Materials
In
total,
90
patients
three
centers
(30
CT-MR
pairs/center)
underwent
treatment
using
volumetric
modulated
arc
therapy
cancer
(PCa)
(60
Gy
in
20
fractions).
T2
were
acquired
addition
(CT)
planning.
2D
supervised
conditional
generative
adversarial
(Pix2Pix).
Patient
preprocessing
steps,
including
nonrigid
registration.
Seven
different
models
trained,
incorporating
one,
two,
or
centers.
Each
trained
24
pairs.
A
all
To
compare
CT,
mean
absolute
error
Hounsfield
units
calculated
entire
pelvis,
prostate,
bladder,
rectum,
bones.
analysis,
differences
D
99%
CTV,
V
95%
PTV,
max
rectum
3D
gamma
analysis
(local,
1%/1
mm)
CT
sCT.
Furthermore,
Wilcoxon
tests
performed
image
obtained
with
those
other
models.
Results
Considering
when
data
test
comes
center
as
training,
not
significantly
model.
Absolute
less
than
1
CTV
every
center.
showed
nonsignificant
between
monocentric
Conclusion
accuracy
sCT,
terms
dose,
equivalent
whether
are
generated
model,
only
eight
MRI-CT
pairs
per
center,
offers
robust
generation,
facilitating
PCa
MRI-only
routine
clinical
use.
Machine Learning Science and Technology,
Journal Year:
2023,
Volume and Issue:
4(2), P. 025023 - 025023
Published: May 18, 2023
Abstract
Accurate
and
efficient
tools
for
calculating
the
ground
state
properties
of
interacting
quantum
systems
are
essential
in
design
nanoelectronic
devices.
The
exact
diagonalization
method
fully
accounts
Coulomb
interaction
beyond
mean
field
approximations
it
is
regarded
as
gold-standard
few
electron
systems.
However,
by
increasing
number
instances
to
be
solved,
computational
costs
become
prohibitive
new
approaches
based
on
machine
learning
techniques
can
provide
a
significant
reduction
time
resources,
maintaining
reasonable
accuracy.
Here,
we
employ
pix2pix
,
general-purpose
image-to-image
translation
conditional
generative
adversarial
network
(cGAN),
predicting
densities
from
randomly
generated
confinement
potentials.
Other
mappings
were
also
investigated,
like
potentials
non-interacting
densities.
architecture
cGAN
was
optimized
with
respect
internal
parameters
generator
discriminator.
Moreover,
inverse
problem
finding
potential
given
density
approached
mapping,
which
an
important
step
near-optimal
solutions