The Reference in Single Source CT

www.siemens.com/somatom-definition-edge
The Reference in Single Source CT
SOMATOM Definition Edge
Answers for life.
SOMATOM Definition Edge
Siemens CT Vision
Today’s reality
Better healthcare for all patients is a key
priority for the entire medical industry.
But the realities of clinical practice often
make this simple-to-understand goal quite
difficult to realize: staying within budgets,
reducing hospital stays, speeding up time to
diagnosis, and dealing with personnel issues,
while maintaining high clinical standards
and throughput. At the same time, patients
demand better and faster results.
2
Our approach
In order to meet our share of responsibility
in addressing these challenges, Siemens,
from the earliest stages of research, product
development, and design, relies upon the
advice and recommendations of external
medical experts to determine our focus – and this focus has been on the needs and
demands of our end users. Over the years,
this focus has been fine-tuned in four
key areas:
• to lead technological and medical
advancement
• to maximize workflow efficiency
• to make state-of-the-art CT affordable
• to set the standard in customer care
Our vision
As a partner to our customers, we create
CT innovations that lift clinical practice to
the next level of excellence and enable wide
access to better patient care. We believe
that even the farthest technical horizons
are temporary and can be surpassed
with consistent dedication to improved
healthcare. This visionary approach, backed
up by the, by far, largest R&D budgets in the
healthcare industry, has made Siemens the
undisputed innovation leader in CT over
the last 35 years. And our ambitious global
team continues to set the trend in an
always changing environment, providing
Answers for Life.
Our solution
In 2008, Siemens introduced the gold
standard in CT technology, still unrivaled
today: the SOMATOM® Definition Flash.
And now, again, Siemens sets the
standard for Single Source CT: the
SOMATOM Definition Edge with the revolutionary Stellar Detector with TrueSignal
Technology. Developed with the clear goal
of providing the latest in CT technology,
the SOMATOM Definition Edge integrates
the unique innovations of the SOMATOM
Definition Flash into a groundbreaking
Single Source CT system. Finally, Single
Source CT imaging can unleash its
full potential: offering uncompromised
diagnostic outcome with highest image
quality, acquired at impressively low
patient radiation. With the SOMATOM
Definition Edge, Siemens again pushes the
boundaries of patient care.
3
SOMATOM Definition Edge
The Reference in Single Source CT
4
See the Unseen
09
Unprecedented spatial resolution
Uncompromised temporal resolution
Clinical field: Cardiovascular
Unparalleled acquisition speed
Clinical field: Acute care
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14
16
18
20
Get More from Less
23
Dose reduction in low-signal imaging
Dose reduction with SAFIRE
Dose reduction with CARE kV
Combined Applications to Reduce Exposure (CARE)
26
28
30
32
Specify the Unspecific
35
Calculi characterization in clinical routine
Gout identification in clinical routine
Reducing metal artifacts in clinical routine
Improved dynamic imaging in clinical routine
38
40
42
44
Benefits and Technical Specifications 46
International Version. Not for distribution in the US.
Scan to see
the unseen of
Edge Technology
features.
www.siemens.com/somatom-definition-edge
5
SOMATOM Definition Edge
The Reference in Single Source CT
See the unseen
Get more from less
Specify the unspecific
For decades, Siemens has been the undisputed innovation leader in high-end CT
imaging. But the clinical need for higher image quality persists. Therefore, we proudly
introduce the SOMATOM Definition Edge with the revolutionary Stellar Detector,
the first fully-integrated detector. Designed to minimize electronic noise, it takes
CT imaging where it has never gone before.
6
The uniqueness of the Stellar Detector allows the SOMATOM Definition Edge
to generate ultra-thin slices, thus delivering the highest spatial resolution in CT.
You can visualize even the finest image details, for example, for the most
accurate stenosis and stent analysis. It lets you see what was previously unseen.
The minimized noise level of the Stellar Detector together with SAFIRE – our
raw-data-based iterative reconstruction – is perfect for ultra low-dose imaging,
eliminating the contradiction of outstanding image quality with minimal dose.
You get more diagnostic quality with less patient radiation.
Additionally, Dual Energy (DE) is a reality for Single Source CT imaging.
With the novel capabilities of the Stellar Detector and the only dose-optimized
Single Source DE scan mode, the SOMATOM Definition Edge enables you to
add tissue characteristics to the morphology. You can now specify formerly
unspecific information for higher diagnostic outcome.
With these unrivaled features, the SOMATOM Definition Edge enters new
frontiers in medical imaging, becoming: The Reference in Single Source CT.
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Edge
Technology
See the Unseen
See the Unseen
Introducing the latest generation of CT detector technology:
Siemens’ unique Stellar Detector, together with innovative Edge
Technology, delivers slices thinner than the detector spacing.
focal spot
Edge Technology
Minimized cross-talk from the
Stellar Detector creates an
almost perfect model of the
focal spot. The result is a slice
thickness of 0.5 mm.
Conventional Technology
Cross-talk resulting
from slice blurring in
conventional detector.
detector
projection
10
A general principle in CT is that thinner slices
deliver more image detail, but also less light
quants per voxel, i.e., higher image noise.
This lowers the signal-to-noise ratio (SNR)
and leads to slice blurring. Conventional CT
compensates by increasing dose. Clinical
experience following the ALARA (As Low As
Reasonably Achievable) principle has shown
that a 0.6 mm collimator width is the optimum combination of slice thickness and
dose. So further reduction of slice thickness
was limited. Until now.
The Stellar Detector
The Stellar Detector introduces the
next generation in detector technology,
succeeding gas and solid-state technology.
Using nanotechnology, it is possible to
miniaturize the electronic components
on the detector elements, enabling their
integration directly at the photodiode.
So, for the first time, the electronics of
the detector elements are fully integrated
in the photodiode. This full electronic
integration is Siemens' revolutionary
TrueSignal Technology.
Edge Technology
Electronic noise and cross-talk are minimized thanks to full electronic integration.
Without cross-talk, intrinsic slice blurring
between neighboring detector rows can
be avoided and individual slice profiles
are much more precise. Siemens’ Edge
Technology creates an almost perfect model
of the focal spot and detector, generating
a slice thickness of 0.5 mm. Thanks to
minimized electronic noise, the 0.5 mm
slice has a sufficient signal contribution
to be used in clinical routine.
Scan to learn
more about
the new
Stellar Detector.
www.siemens.com/edge-stellar
11
0.30
mm
Unprecedented
spatial resolution
Innovation delivers outstanding results
High spatial resolution in combination
with a high signal-to-noise ratio (SNR) is a
reliable indicator for excellent image quality.
Together they describe the image detail level
and sharpness that can be made visible while
acquiring diagnostic CT images. In addition,
a homogenic slice profile with the same spatial resolution and SNR everywhere in the
entire Field of View (FOV) is essential for consistent high image quality. Other approaches
in the market had to make compromises, for
example by reducing the FOV size.
12
Increased image detail
In addition to the Stellar Detector, the
SOMATOM Definition Edge is equipped with
Siemens’ renowned STRATON® tube with
z-Sharp™ Technology. This combination is
the essence of increasing spatial resolution.
Using a flying focal spot with two distinct
X-ray beams, z-Sharp acquires two individual, overlapping slices. With Edge Technology, the Stellar Detector now delivers slices
with a thickness of 0.5 mm, resulting in a
spatial resolution of up to 0.30 mm, which
is equivalent to approximately 19 lp/cm.
Higher signal-to-noise ratio
But how can the reduced light quants of
a 0.5 mm slice be compensated for? The
secret is the TrueSignal Technology of the
Stellar Detector. Instead of increasing dose,
it makes more efficient use of the initially
available quants per voxel: As the electronic
noise of the detector is virtually eliminated,
the overall noise is reduced so that the quants
contribute to a higher SNR. Consequently,
thin slices of 0.5 mm can be used in
clinical practice.
More consistent image quality
By acquiring two distinct slices, z-Sharp
collects twice the amount of projections.
This avoids miscalculation of data points,
as they are measured and not interpolated,
providing a higher data quality. And as the
slices are acquired in parallel, the data points
are equidistant, resulting in a more consistent slice thickness compared to conjugate
approaches. Adding the reduced slice blurring
of the Stellar Detector, the slice profile overall becomes more homogeneous with consistent spatial resolution over the entire FoV.
13
142
msec
Uncompromised
temporal resolution
Uncompromised rotation speed
The core technology to achieve high
rotation speed is the renowned STRATON
tube. Based on direct anode cooling, it
eliminates the need for heat storage and
has an unmatched compact design.
Together with new gantry architecture,
this enables an additional increase in the
rotation speed of the SOMATOM Definition
Edge. Increased rotation speed means
shorter rotation times. That means that the
available signal per rotation is also reduced,
which results in lower SNR or higher image
14
noise. Until now, this typically had to be
compensated for by increasing the applied
current which consequently required a
higher generator power. But the Stellar
Detector with TrueSignal Technology
reduces electronic noise in the detector.
This optimizes the initial SNR and thus
avoids the need to further increase
generator power.
Uncompromised performance
The unique combination of Stellar Detector,
STRATON tube and new gantry is the key
benefit of the SOMATOM Definition Edge.
With a rotation speed of 0.28 sec, it delivers
a temporal resolution of 142.5 msec. At the
same time, it utilizes the unique spatial
resolution of up to 0.30 mm provided by
the Stellar Detector. And its gantry concept
now makes it possible to use it within the
entire FoV of up to 500 mm. Only with this
uncompromised performance can you
achieve outstanding clinical results.
Uncompromised image detail
High temporal resolution is essential for
motion-artifact-free imaging, e.g., in cardiac
examinations to perform accurate stenosis
measurements. But this benefit is contradicted when compromises like reduced
image detail or limited FoV have to be made
in order to utilize high rotation speeds.
Therefore, the SOMATOM Definition Edge
was specifically designed to go beyond
these limitations. Its revolutionary Stellar
Detector provides unprecedented image
detail independent of rotation speed.
15
Clinical field:
Cardiovascular
Cardiac imaging combines two
crucial requirements in CT
imaging: high spatial resolution
at high temporal resolution. One
example that demonstrates the
benefits of the new SOMATOM
Definition Edge regarding
artifact-free high resolution is
stent imaging in cardiology.
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High spatial resolution
In cardiology, high spatial resolution only
makes sense when it can be provided in
concert with high temporal resolution.
With only limited spatial resolution, the
visualization of small occlusions might be
impaired, resulting in blurring artifacts.
These may affect the diagnosis, as it can
conceal the actual stenosis. With higher
spatial resolution, blurring artifacts are
reduced, allowing better assessment of
the lumen.
High temporal resolution
Spatial resolution is of no benefit without
high temporal resolution. Limited spatial
resolution can lead to motion artifacts from
the respective vessel. This increases the
danger of false positive findings, meaning
a stenosis is diagnosed, although the
finding is a result of the misinterpreted
fuzzy visualization of the vessel. Therefore,
high spatial resolution must be delivered
together with high temporal resolution;
not one or the other.
In-stent restenosis
A common clinical question typically posed
in stent follow-up examinations is whether
the vessel has re-occluded after the stent
has been set. As stents are very small
objects within constantly moving vessels,
this procedure requires precise image details
without motion artifacts. With the unique
combination of highest spatial resolution at
uncompromised temporal resolution, the
SOMATOM Definition Edge offers the most
advanced solution for this clinical challenge.
collimation:
128 x 0.5 mm
spatial resolution:
0.30 mm
temp resolution:
142 msec
scan time:
5 sec
scan length:
119 mm
rotation time:
0.28 sec
CTDIvol:
38 mGy
DLP:
656 mGy cm
eff. dose:
9.2 mSv
High resolution imaging of
stents at uncompromised
temporal resolutions allows
for sound exclusion of
in-stent stenosis.
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230
mm / sec
Unparalleled
acquisition speed
In conventional CT systems, high
resolution means scanning at
reduced pitch. With z-Sharp,
high resolution is independent
of pitch, making high resolution
available for high-pitch acute
care examinations.
18
Uncompromised spatial resolution
One of the most challenging demands
in CT is providing high acquisition speed
without compromising spatial resolution;
for example, in acute-care scenarios when
unconscious or uncooperative patients
have to be scanned quickly. Here the
‘golden hour’ to diagnosis mandates
precise localization and identification of
critical injuries. The goal is to prevent
motion artifacts when patients have only
a limited ability to hold their breath.
In such cases the SOMATOM Definition
Edge is in a class of its own. The new level
of image detail with a spatial resolution of
up to 0.30 mm provided by the Stellar
Detector allows visualizations of even the
finest fractures or lesions. Additionally,
the newly designed gantry, together with
Siemens’ most advanced patient table,
now allows an acquisition speed of up to
230 mm/sec. This takes motion out of
the equation, increasing the diagnostic
reliability in such crucial cases.
Conventional technology
R2
z-Sharp technology
R1
pitch = 1.4
R2
R1
pitch = 1.0
High-pitch high-resolution CT
Increasing spatial resolution beyond the
detector width requires overlapping slices.
For conventional CT systems, this means
reducing pitch to facilitate the slice overlap.
For scans requiring high pitch, the reduced
or missing overlap then reduces spatial
resolution. But with z-Sharp, the overlap
results from an acquisition with two distinct
projections coming from the STRATON tube.
Consequently, the two slices overlap independently of the pitch used and can always
provide highest resolution.
R2 R1
pitch = 0.55
R1
pitch = 1.4
R1
pitch = 1.0
R1
pitch = 0.55
The uniqueness of the SOMATOM Definition
Edge is the combination of the Stellar
Detector, the STRATON tube with z-Sharp,
the new gantry with 0.28 sec rotation speed,
and the patient table that supports a pitch
of 1.7. This allows a scan speed of up to
230 mm/sec. Clinically, this means scanning
the whole heart in half a second, a 50 cm
thorax in roughly two seconds or performing
a two-meter scan of the entire body in
nearly eight-and-a-half seconds, all at a
spatial resolution of up to 0.30 mm.
19
Clinical field:
acute care
Acute care is one of the most
challenging applications in CT.
This clinical field shows how the
new SOMATOM Definition Edge
is the answer when examining
an acute-care patient with severe
injuries of the upper spine.
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The golden hour
Acute care demands the highest spatial
resolution at the fastest possible acquisition
speed, which is very challenging. The
reason is that the ‘golden hour’ is crucial:
Appropriate therapy which is instituted
within this time frame is likely to have a
much more significant impact on improving
patient outcome by decreasing morbidity
and mortality. Consequently, the guiding
imaging for these decisions must deliver the
required answers quickly. Therefore, CT is
the modality of choice.
High-resolution high-speed imaging
In addition to the fact that every second
counts in the golden hour, there is another
reason to use the fastest possible acquisition
speed. Acute-care patients are often
uncooperative, so it is essential that the
CT scan is performed as fast as possible to
reduce movement artifacts. But you want to
be sure you are not reducing spatial resolution. When looking at fractures, for example,
it is essential to assess whether larger
fractures or broken bones have ruptured small
vessels and caused internal bleeding, or
whether very small fractures of the spine
have impacted the spinal cord. So it is
imperative to acquire the highest possible
spatial resolution at the fastest possible
acquisition speed. The SOMATOM Definition
Edge with the unique STRATON tube makes
spatial resolution independent of the
selected pitch. And having the patient table
from the SOMATOM Definition Flash at
a pitch of 1.7 is possible. This allows an
acquisition speed of up to 230 mm/sec at
a spatial resolution of 0.30 mm.
collimation:
128 x 0.5 mm
spatial resolution:
0.30 mm
scan time:
7.6 sec
scan length:
230 mm
rotation time:
1.0 sec
CTDIvol:
22.4 mGy
DLP:
590 mGy cm
eff. dose:
8.9 mSv
Spine image of a 70-year-old
patient with vertebrae
degeneration visualizing even
the finest bone structures.
21
TrueSignal
Technology
Get More from Less
Get More from Less
The unique Stellar Detector with TrueSignal Technology
reflects the continuation of Siemens’ commitment to
deliver best image quality at lowest signal or lowest dose.
The low signal capability
of a detector can be described
best by a high SNR. The Stellar
Detector with TrueSignal
Techno­logy minimizes electronic
noise – optimal for low signal
and dose imaging.
24
There are various reasons to scan with
low signals. For example, bariatric patients
can cause strong attenuation. But low
signals can be fully intentional, mainly
driven by the desire to reduce dose. Many
recent innovations, especially iterative
reconstruction solutions, reflect this.
They were explicitly developed to lower the
applied dose. So it follows to introduce a
detector that is specially optimized for
low-signal imaging: the Stellar Detector
with TrueSignal Technology.
TrueSignal Technology
TrueSignal Technology with the full
integration of the Stellar Detector virtually
eliminates electronic noise in the detector
elements. The resulting SNR is increased so
that even very low signals are sufficiently
strong enough for the detector to cope with.
Low-signal images benefit from increased
sharpness and clarity, as the detector can
now differentiate the signal of an individual
voxel much better than the surrounding
image data.
SOMATOM
Definition Edge
40 cm
40 cm fit
noise
[HU]
Conventional CT
40 cm
40 cm fit
300
at 200 mA
-25%
-20%
200
at 300 mA
-12%
at 400 mA
100
current [mA]
0
0
Comparable noise level at lower signal
The outcome can be best visualized when
looking at noise measurements of large
patients. When comparing conventional CT
technology with the SOMATOM Definition
Edge and the Stellar Detector with TrueSignal
Technology, the resulting noise is more or
less the same for high signals. But when
the signal is lowered – either by high
attenuations from obese or broadshouldered patients, or by reducing the
applied mA – the impact of TrueSignal
Technology increases.
50
100
150
200
250
300
350
400
450
500
Dose savings at the
same noise level with
SOMATOM Definition Edge
Due to minimized electronic noise, the
available signal is less impaired, so that the
same noise level can be achieved with
significantly lower signal levels. This means
that when there is high attenuation from
very large patients, the detector can make
better use of the resulting low signal. Or,
the dose can be further reduced to achieve
a comparable image quality.
25
Up to
25%
Dose reduction in
low-signal imaging
More and more patients suffer
from obesity. Therefore, the
capability to deliver sound
bariatric imaging is essential for
state-of-the-art CT imaging.
26
Obesity – the new global disease
One example of how reducing electronic
noise with TrueSignal Technology benefits
low-signal efficiency is bariatric imaging.
Obesity is on the rise: In the US and some
European countries, more than 1/3 of the
population is considered obese. Therefore,
there is a growing need to scan large
patients. However, obese patients attenuate
a significant portion of the signal, so
regardless of scanner ergonomics, many
conventional CT systems are unsuitable,
as the signal is too low.
Optimized bariatric imaging
By minimizing electronic noise, the
detector’s SNR increases, providing much
more flexibility in handling low signals. This
is essential for bariatric imaging, as often
maximum power is applied, but the signal
reaching the detector is very low. Conventional detectors have a comparatively high
intrinsic noise level and impaired image
quality. Due to the electronic integration of
the Stellar Detector, this noise level is
significantly lower, so the available signal
can be processed more efficiently.
State-of-the-art CT systems have to react
to the new challenges presented by the
increasing number of bariatric patients. This
means having the appropriate ergonomics
to handle these patients, as well as having
the technology to achieve the image quality
necessary for reaching sound diagnoses.
The SOMATOM Definition Edge delivers the
ideal solution with a 78 cm gantry bore, and
a table load capacity of more than 300 kg,
all enhanced by the new Stellar Detector
with TrueSignal Technology.
collimation:
64 x 0.6 mm
spatial resolution:
0.33 mm
scan time:
1.5 sec
scan length:
155 mm
rotation time:
0.5 sec
CTDIvol:
21 mGy
DLP:
325 mGy cm
eff. dose:
4.55 mSv
Conventional detector
technologies have difficulties
handling low signals, resulting,
for example, in streak artifacts
(left). With its higher SNR,
the Stellar Detector is perfectly
designed to cope with low
signals (right).
27
Up to
60%
Dose reduction
with SAFIRE
* The following test method was used
to determine a 60% dose reduction
when using the SAFIRE
reconstruction software: Noise,
CT numbers, homogeneity,
low-contrast resolution and highcontrast resolution were assessed
in a Gammex 438 phantom.
Low-dose data reconstructed with
SAFIRE showed the same image
quality compared to full-dose data
based on this test. Data on file.
28
Low dose is low-signal imaging
The significant reduction of mA when scanning with iterative reconstruction solutions
like SAFIRE (Sinogram Affirmed Iterative
Reconstruction) also results in lower signals
at the detector, so these examinations also
benefit from the advantages of TrueSignal
Technology. The computational power of
systems like FAST IRS fascilitate iterative
reconstruction in a wider range of clinical
applications. The number of iterative
reconstruction scans is thereby increased,
resulting in more benefits for patients.
Iterative reconstruction
After the initial reconstruction using
weighted filtered back projection (WFBP),
the CT images are retransferred to raw data.
By comparing this new synthetic raw data
with the acquired data, differences can be
identified by applying a dynamic raw-data
based noise model. An updated image is
then reconstructed, with reduced image
noise but without noticeable loss of sharpness. This is repeated several times – image
noise can be incrementally reduced and
geometrical imperfections corrected.
SAFIRE and the Stellar Detector
Superior image quality in regard to
contrast and noise can be obtained with
this methodology. And it can be used to
initially acquire the data at lower mA and
then compensate the image quality during
the reconstruction. By using this approach,
SAFIRE enables a dose reduction of up to
60%.* This reduction in dose means a lower
signal at the detector. So now unique lowsignal capabilities of the Stellar Detector
further optimize the image quality, resulting
in even higher sharpness and clarity.
collimation:
128 x 0.6 mm
spatial resolution:
0.33 mm
scan time:
11 sec
scan length:
245 mm
rotation time:
0.5 sec
CTDIvol:
8.5 mGy
DLP:
460 mGy cm
eff. dose:
6.9 mSv
Significantly improved image
quality at lower dose using
SAFIRE with the Stellar Detector
(right) compared to a regular
WFPB on a conventional
detector (left).
29
Up to
60%
Dose reduction
with CARE kV
The main dose-relevant
parameters for a CT scan are the
applied current and voltage,
depending on the examination
type and the patient's habitus.
Only when taking all parameters
into consideration, does
dose protection become comprehensive and patient-centric.
30
Real time dose modulation
In 1994, Siemens introduced CARE Dose4DTM
to actively modulate the applied power for
scans, according to patients’ anatomy.
CARE Dose4D aims to regulate mA in real
time so that image quality is uniform across
the whole scan range. But CT scanning is
not only adapting mA values: The right kV
settings play an equal if not more important
role in achieving optimum clinical outcome.
Changing kV values also means adapting all
other values according to the respective
patient and examination type.
CNR optimized kV settings
After the patient’s stature and the mAs, the
selected voltage (kV) is the third doserelevant value for a CT scan. Selecting the
right kV settings is essential for achieving
optimal clinical outcome. CARE kV can automatically suggest kV and effective mA to
optimize the contrast-to-noise ratio (CNR) of
the image, while limiting the applied dose.
CARE kV takes the patient’s habitus from the
topogram and the chosen examination type
(non-contrast, bone, soft tissue, vascular)
into consideration, proposes the appropriate
kV, and sets all other parameters accordingly
to get the defined CNR. Reducing the tube
voltage helps optimizing dose and improves
image quality, e.g., for contrast-media
enhanced examinations. With the new,
improved STRATON tube, the voltage range
is lowered to 70 kV. This, together with the
unique CARE Child scan modes, helps further
reduce the dose for pediatric or neonate
patients. With these features, an additional
dose reduction of up to 60% is possible.
Additionally, the system identifies bariatric
kV usage [%]
100
90
Without CARE kV
80
70
60
With CARE kV
50
40
30
20
10
0
patients and sets the parameters accordingly
to make full use of the system’s reserves to
optimize CNR, and achieve the best image
quality possible for these patients.
70
80
100
Benefit for many patients
An evaluation of CARE kV with more than
12,000 patients in the first months after its
introduction showed that there was a clear
shift towards 100 kV and 80 kV scans (see
above). Dose could be saved in more than
two thirds of these patients, compared to
the initial protocols. And the dose reduction
itself was significant. For example, regular
abdomen scans could be reduced to below
10 mGy using 100 kV, down from 14.1 mGy
with the former standard protocol set at
120 kV. This dose reduction of approximately
120
140
Tube voltage [kV]
Lower dose in 67% of patients
with CARE kV
30% came with no compromise in image
quality; CNR could be maintained with
no impact on workflow, as all system
parameters are automatically set.
31
Combined Applications
to Reduce Exposure (CARE)
Dose reduction lies at the
heart of the CARE philosophy.
Each application is designed to
contribute dose reduction during
every step of the examination
process resulting in an absolute
minimum exposure.
Radiation
exposure 9
[mSv]
8
Dose reduction in cardiac CT
7
6
5
4
3
2
1
0
32
Adaptive
ECG Pulsing
CARE kV
CARE
Dose4D
MinDose
Adaptive
Dose Shield
SAFIRE
Comprehensive dose protection
Following the ALARA principle, Siemens
introduced its CARE philosophy in the
mid-1990s. The idea is to utilize every
means available to reduce patient exposure.
Siemens is the only vendor to offer a
dose protection portfolio that comprehensively takes all relevant scan parameters
into consideration and optimizes the
scan accordingly, from patient size to
examination type, from mA to kV, and
from scan preparation to data evaluation.
collimation:
128 x 0.5 mm
spatial resolution:
0.30 mm
temp resolution:
142 msec
scan time:
5 sec
scan length:
119 mm
rotation time:
0.28 sec
CTDIvol:
7 mGy
DLP:
95 mGy cm
eff. dose:
1.33 mSv
Cardiac examinations are
amongst the most sensitive
when it comes to dose,
so combining all available
applications to reduce
exposure is key.
33
HiDynamics
Specify the Unspecific
Specify the Unspecific
The TrueSignal Technology of the Stellar Detector brings yet another
innovation: HiDynamics. Its unique, full dynamic range provides higher
image sensitivity, especially for low-signal and low-energy scans.
A larger dynamic range expands
the detector’s sensitivity. As in a
backlit photo with a conventional camera, the front regions
turn black. But with higher sensitivity, details remain visible.
36
1st scan
140 kV
2nd scan
80 kV
HiDynamics
Thanks to the full electronic integration of
the TrueSignal Technology, the Stellar
Detector can now utilize its full dynamic
range instead of having to switch bandwidth
like conventional detectors. This unique
feature is called HiDynamics. It increases the
detector’s sensitivity at the respective energy
level and allows for differentiation of
even the slightest signal changes, especially
when scanning with very low kV levels.
Comparison of the 80 kV Dual
Energy data set (left) with the
140 kV Dual Energy data set
(right) shows: almost identical
image detail level in 80 kV due
to the improvement resulting
from HiDynamics.
The benefits of the Stellar Detector
The benefits of TrueSignal Technology and
HiDynamics are also clear in functional
imaging applications, such as Dual Energy,
as well as in dynamic examinations. They
acquire multiple scans of the same region
to add functional information, such as
tissue characteristics or perfusion data to
the morphology. In both cases, the scan
modes acquire data at low kV. HiDynamics
significantly increases the detail level and
sharpness of the images for these data sets.
Dose-optimized Single Source DE
When multiple scans of the same region
have to be performed, dose protection
becomes even more important in order to
adhere to the ALARA principle. Therefore,
it is imperative to exploit every possibility
to reduce dose. Following this philosophy,
Siemens has introduced a Single Source
Dual Energy scan mode that utilizes all
dose-reduction functionalities without
limitations: e.g., CARE Dose4D for real-time
mA modulation, or SAFIRE to reduce the
mA created by iterative reconstruction.
The scan mode consists of two successive
spiral scans at different energy levels. In
order to avoid doubling the dose, both spirals are performed at half the dose, so that
there is no dose penalty for the resulting
Dual Energy image. But, as it uses regular
spirals, all dose reduction features can be
utilized without limitations. The capabilities
of the Stellar Detector regarding low
dose / signal imaging represents the
industry’s only Single Source Dual Energy
scan mode optimized for low dose.
37
Calculi characterization
in clinical routine
Kidney stones are a good
example of how tissue
characterization can lead
to finding the appropriate
therapy. Dual Energy information adds tissue information
to the morphology.
38
Urinary stone disease
Approximately 13% of men and 7% of
women in the United States will be
diagnosed with urinary stone disease in
their lives. Most stones are symptomatic
and cause pain, obstruction, and infection.
They frequently require visits to the emergency room, hospitalization, mechanical
extraction or even surgical removal. Some
stones may be asymptomatic and are
only detected incidentally. However, even
when stones are initially asymptomatic,
symptoms may develop very quickly and
require intervention later. Current evidence
from the study “Urological Diseases in
America” suggests an increasing prevalence
of urinary stone disease in the United
States. In addition, the likelihood of recurrence is estimated to be up to 50 % during
a five-year period. Thus, the diagnosis of
kidney stones has substantial impact with
respect to patient morbidity and healthcare
budgets. The imaging modality of choice for
urinary stone disease is a low-dose, noncontrast CT scan. It is very easy to perform,
does not require intravenous contrast and
covers the entire abdomen and pelvis. With
this imaging modality, nearly all stone types
can be visualized. The essential benefit in
the diagnosis with Dual Energy CT is that
the stone type can be identified. With this
information at hand, the appropriate
treatment can be applied. For patients, this
means that many interventional treatments
can be avoided, as it can be determined
upfront if a stone can be treated with
drugs or not.
collimation:
128 x 0.6 mm
spatial resolution:
0.33 mm
scan time:
1.3 sec
scan length:
117 mm
rotation time:
0.5 sec
CTDIvol:
5.28 + 3.02 mGy
(140 / 80 kV)
DLP:
80 + 40 mGy cm
(140 / 80 kV)
eff. dose:
1.8 mSv
Characterization with syngo
Single Source DE Kidney Stones
supports treatment decisions.
39
Gout identification in
clinical routine
Gout is the most widespread
form of crystal arthropathy and a
common inflammatory joint
disease. However, gout is difficult
to diagnose. Dual Energy can
detect gout in regions that are
often overlooked.
40
Gout
Gout is the most widespread form of
crystal arthropathy and the most common
inflammatory joint disease in men. It is
caused by the deposition of uric acid
crystals in joints. Up to 1 in 200 people in
the western world, 2.1 million people in the
US, and some 1.5 million people in Germany
are currently afflicted by this painful,
destructive disease. Furthermore, due to our
eating habits, these figures are constantly
increasing. Gout can affect numerous joints
throughout the body, especially during
recurrent episodes. The classic symptoms
of gout are painful, visibly swollen
peripheral joints. However, gout is difficult
to diagnose, as there are various forms of
arthritis that have similar symptoms. With
Dual Energy CT and syngo® Dual Energy
Gout, a non-invasive assessment of gout is
feasible. The algorithm color codes different
attenuation values at different energy levels
so that the uric acid crystals are color coded
in red, while calcium and bone formations
are displayed in blue. Thus, uric acid pro-
duced by the disease is directly verified,
confirming the definite diagnosis of gout.
The benefit for patients is not only that
the painful puncture in a conventional
examination can be avoided, but also
that the risk of false negative outcomes
is reduced in cases where the puncture
misses the respective tissue.
collimation:
128 x 0.6 mm
spatial resolution:
0.33 mm
scan time:
4 sec
scan length:
181 mm
rotation time:
0.5 sec
CTDIvol:
3.32 + 4.46 mGy
(140 / 80 kV)
DLP:
71 + 95 mGy cm
(140 / 80 kV)
eff. dose:
0.13 mSv
Clear identification with syngo
Single Source DE Gout avoids
false negative diagnosis of
conventional procedures.
41
Reducing metal
artifacts in clinical routine
Metal artifacts pose severe
difficulties in CT imaging
due to the resulting artifacts.
Single Source Dual Energy
now delivers a solution.
42
Metal artifact reduction with Dual Energy
A big challenge in CT imaging is the impact
of metal objects on image quality. Due to
the high attenuation of metal compared to
the surrounding tissue, images can suffer
from streaks or even shadows around
the metal objects. The cause for this is
so-called ‘beam starvation.’ Typical metal
artifacts result from implants, e.g., in teeth,
or when clamps and screws are used in
invasive treatments. But when it comes to
treatment decisions or treatment follow-up,
it is essential that the image is as
artifact free as possible. For example, when
assessing organs in the pelvic region, images
are often impaired if the patient has a hip
prosthesis. The high attenuation of this massive metal object causes adjoining regions
to suffer from very low signals. Until now,
these artifacts could not be compensated
for. But now, two solutions come together:
The unique Stellar Detector in the
SOMATOM Definition Edge is specifically
optimized to handle low signals with its
TrueSignal Technology and HiDynamics.
And syngo Dual Energy Monoenergetic
Imaging enables the minimization of metal
artifacts by specifically selecting the respective kV level at which the metal objects have
least impact on image quality. With this
unique combination, implants, clamps or
screws can be ideally dealt with in order to
obtain the highest diagnostic outcome.
collimation:
128 x 0.6 mm
spatial resolution:
0.33 mm
scan time:
5 sec
scan length:
228 mm
rotation time:
0.5 sec
CTDIvol:
12.31 + 4.46 mGy
(140 / 80 kV)
DLP:
380 + 129 mGy cm
(140 / 80 kV)
eff. dose:
7.64 mSv
Significant reduction of metal
artifacts from hip implant with
syngo Single Source DE Monoenergetic delivers much higher
diagnostic image quality
43
Improved dynamic
imaging in clinical routine
Perfusion information is
crucial in many clinical fields
such as stroke or tumor
assessments. The Adaptive 4D
Spiral is key to making these
exams ready for clinical practice.
44
Stroke is one of the three most frequent
causes of death worldwide. The diagnosis
and treatment of stroke cases is a clinical
field in which time is of the essence – or
where ‘time is brain,’ meaning that the right
decisions have to be made ideally within the
first hours after the first symptoms have
occurred. Consequently, it is essential that
the diagnostic information is delivered
quickly, reliably, and accurately, and gives
a comprehensive overview about the status
of the disease.
Adaptive 4D Spiral and HiDynamics
With the Adaptive 4D Spiral, Siemens has
introduced a scan mode that performs perfusion evaluations beyond the limitations of
a static detector. By applying a continuously
repeated bi-directional, smooth table
movement over the desired scan range,
a perfusion assessment covering a region
of up to 15 cm can be performed. Recent
publications have shown that a scan range
of approximately 10 cm is ideal to assess
brain perfusion. Consequently, the neuro
perfusion scan modes with the Adaptive 4D
Spiral are specifically set to this length
for stroke evaluations. In addition, the
SOMATOM Definition Edge, with the Stellar
Detector and HiDynamics, is the perfect
choice for better differentiation of the
perfusion level, as brain perfusion studies
are typically performed at 80 kV. Regardless
of cause – from infarctions due to stroke
and extensive bleeding, to subarachnoid
hemorrhage or a ruptured aneurysm – seeing clearly makes a crucial difference
in determining treatment.
collimation:
128 x 0.6 mm
scan time:
45 sec
scan length:
100 mm
rotation time:
0.285 sec
CTDIvol:
260 mGy
DLP:
3069 mGy cm
eff. dose:
6.4 mSv
Comprehensive perfusion
evaluation with syngo VPCT
Neuro delivers crucial
information regarding tissue
at risk after a stroke.
45
SOMATOM Definition Edge
The Reference in Single Source CT
See the unseen
Edge Technology – The
reference in image quality
• Unprecedented spatial resolution
• Uncompromised temporal resolution
• Unparalleled acquisition speed
Get more from less
TrueSignal Technology – The
reference in dose efficiency
• Optimized low-signal imaging
• Optimized low-dose imaging
• Optimized patient-centric imaging
Specify the unspecific
HiDynamics – The reference
in functional imaging
• Routine ready Single Source Dual Energy
• Routine ready metal artifact reduction
• Routine ready dynamic imaging
46
Technical Specifications
• Stellar Detector with TrueSignal Technology
• 256 x 0.5 mm slices and 0.30 mm spatial
resolution with Edge Technology
• Dose-optimized Single Source Dual Energy
and HiDynamics
• 128-slice acquisition with STRATON tube
and z-Sharp Technology
• Up to 384-slice reconstruction
• 0.28 sec rotation time with
142.5 sec temporal resolution
• 1.7 maximum pitch with
230 mm/sec acquisition speed
• Patient table: 227 kg capacity
(300 kg optional), 200 cm scan range
• With up to 60 fps FBP and
20 fps SAFIRE reconstruction speed
• 4D scan range: 15 cm for perfusion,
48 cm for CTA imaging with
Adaptive 4D Spiral
• Reduced energy consumption by up to
20% in system stand-by with the
Stellar Detector
47
In the event that upgrades require FDA approval,
Siemens cannot predict whether or when the FDA will
issue its approval. Therefore, if regulatory clearance
is obtained and is applicable to this package, it will be
made available according to the terms of this offer.
On account of certain regional limitations of sales
rights and service availability, we cannot guarantee
that all products included in this brochure are available
through the Siemens sales organization worldwide.
Availability and packaging may vary by country and is
subject to change without prior notice. Some/all of the
features and products described herein may not be
available in the United States.
The information in this document contains general
technical descriptions of specifications and options as
well as standard and optional features which do not
always have to be present in individual cases.
Siemens reserves the right to modify the design,
packaging, specifications, and options described herein
without prior notice. Please contact your local Siemens
sales representative for the most current information.
Note: Any technical data contained in this document
may vary within defined tolerances. Original images
always lose a certain amount of detail when reproduced.
Global Siemens Headquarters
Siemens AG
Wittelsbacherplatz 2
80333 Muenchen
Germany
SOMATOM Definition Edge is under development,
and is not commercially available in the US.
The information about SAFIRE (Sinogram Affirmed
Iterative Reconstruction) is being provided for planning
purposes. The product is pending 510(k) review, and is
not yet commercially available in the US. In clinical
practice, the use of SAFIRE may reduce CT patient dose
depending on the clinical task, patient size, anatomical
location, and clinical practice. A consultation with a
radiologist and a physicist should be made to determine the appropriate dose to obtain diagnostic image
quality for the particular clinical task.
Courtesy list
Department of Radiology, University of Erlangen, Germany
Mayo Clinic, Rochester (Minnesota), USA
Nan Xi Shan Hospit al / Guilin, P.R. China
Beihua University 1st Hospital / Jilin, P.R. China
Order No. A91CT-04015-51C1-7600 | Printed in Germany
CC CT WS 11111.5 | © 11.2011, Siemens AG
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Germany
Phone: +49 9131 84 0
www.siemens.com/healthcare
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Medical Solutions
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& Radiation Oncology
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