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8/12/2019 0910 Prokop Cardiac CT
http://slidepdf.com/reader/full/0910-prokop-cardiac-ct 1/6
Mathias Prokop, MD: Cardiac CT- what comes after the
slice race?
May 16, 2008- 9:10
Stanford Radiology 10th Annual Multidetector CT
Symposium
Cardiac CTCardiac CT – – what comes after the slice race?what comes after the slice race? A critical analysis of where we stand and what we need A critical analysis of where we stand and what we need
10th Annual International Symposium on Multidetector-Row CT
Las Vegas, May 13Las Vegas, May 13--16, 200816, 2008
Mathias Prokop, MD PDMathias Prokop, MD PDUniversity Medical Center UtrechtUniversity Medical Center UtrechtThe NetherlandsThe Netherlands
Member, advisory boardMember, advisory board
Philips Medical SystemsPhilips Medical Systems
CT Performance
n c e
100.0
1000.0
Performance = coverage per second / eff. slice thickness
64-slice
P e r f o r m a
0.1
1.0
10.0
1985 1990 1995 2000 2005
Conventional
Spiral
Dual-slice 4-slice
8-slice16-slice
2010
The Slice Race
MDCT Scanner Generations
4-slice CT
1998
Fast scans
Spiral CT: 6cm in 30s
high resolution
for most
organ systems
4 x1 mm4 x1 mm 25 s scan25 s scan
16-sl ice CT
2002
Fast scans +
for all organ
systems
16 x0.75 mm16 x0.75 mm 8 s scan8 s scan
16x0.75 mm
13 s scan duration
Faster Scans ?
Scanning may become too fast
r tca or :
• Large aneurysms
• Slow flow
• Peripheral runoff
• Decreased &
inhomogenous contrast
8/12/2019 0910 Prokop Cardiac CT
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Mathias Prokop, MD: Cardiac CT- what comes after the
slice race?
May 16, 2008- 9:10
Stanford Radiology 10th Annual Multidetector CT
Symposium
64-sl ice CT
2005
Fast scans +high resolution +
for all organ
systems
Gated
thoracoabdominal
CTA
4-slice CT
1998
Coronary CTA
4 x1 mm4 x1 mm 40 s scan40 s scan
16-sl ice CT
2002
Fast scans +
for all organ
systems
16 x0.75 mm16 x0.75 mm 20s scan20s scan
CATSCAN Trial - Qualifier
became feasible
64-sl ice CT
2005
RCARCAstentstent
LAD Coronary CTA
became practicable
Multi-detector CT
Scanner Generations
1st gen. 2nd gen. 3rd gen. 4th gen.
1998 2000-02 2004-05 2006-08
4 rows 16 rows64 rows
320 rows
32 rows
+ z-FFS
64 rows
+ new detector
rows + z-
+ dual source
128 rows + z-FFS
Beyond the Slice Race
4th Generation Scanners
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Mathias Prokop, MD: Cardiac CT- what comes after the
slice race?
May 16, 2008- 9:10
Stanford Radiology 10th Annual Multidetector CT
Symposium
Image quality• Spatial resolution
• Ima e noise
Beyond the Slice Race
Important Scanner Features
• Artifacts / temporal resolution
Scan speed
Coverage
Radiation dose / prospective triggering
Multi-detector CT
4th Generation
Dual source
• Two x-ray tubes
Siemens
Somatom Definition
• Air-bearing gantry
Wide detector
• 8-16 cm
ps
Toshiba Aquilion One
Philips iCT
New detector / iterative recon.
• Higher resolution / less noise
GE CT750 HD
4th Generation Scanners
Siemens
Somatom Definition
Dual source
New tube with z-FFS
Temporal resolution
Dual energy
85 ms85 ms
4th Generation Scanners
Toshiba
Aquilion One
Wider detector (320x0.5mm = 16cm)
Cone beam recon + scatter correction
Full organ coverage
Dynamic scanning
Courtesy P. Rogalla, Berlin
4th Generation Scanners
Philips
iCT
Wider detector (128x0.625mm = 8cm)
Air-bearing gantry (270ms rotation)
New tube with z-flying focal spot
2D scatter grid
Compromise resolution / speed / coverage
4th Generation Scanners
GE
CT750 HD
New detector material and design
Iterative image reconstruction
Spatial resolution / noise
Dual energy
8/12/2019 0910 Prokop Cardiac CT
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Mathias Prokop, MD: Cardiac CT- what comes after the
slice race?
May 16, 2008- 9:10
Stanford Radiology 10th Annual Multidetector CT
Symposium
Detector Slices Width
GE CT750 HD 64x0.625 64 4 cm*
4th Generation Scanners
Detectors
Philips iCT 128x0.625 256 8 cm
Siemens Definition 32x0.6 64 1.9 cm
AS+ 64x0.6 128 3.8 cm
Toshiba One 320x0.5 320 16 cm
* New detector material
Tubes Rotat. pro. retro.ms ms ms
4th Generation Scanners
Temporal Resolution
-
Philips iCT 1 270 140 40-140
Siemens Definition 2 330 85 40-85
AS+ 1 300 150 50-150
Toshiba One 1 350 180 50-180
width pro. retro.
GE CT750 HD 4 cm 7 6
4th Generation Scanners
Number of Heartbeats to Scan the Heart
Philips iCT 8 cm 3 3
Siemens Definition 1.9 cm 8 7
AS+ 3.8 cm 4 4
Toshiba One 16 cm 1 1-3
14cm scan length
Prospective or Retrospective ?
320-slice CT
Retrospective, 2 heartbeats
Heart rate: 58 bpm
Heart rate: 92 bpm
Courtesy of P. Rogalla, Charite, Berlin, Germany
Prospective, 1 heartbeat
Beyond the Slice Race
Functional CT
Morphology• Coronaries
• Heart + vessels
Beyond the Slice Race
CT Applications
• Standard for all organ
systems
16-slice sufficient
Perfusion• Myocardium
Motion• Cardiac function
• Joint motion
• Breathing
• Brain, lung
• Tumors
All other indications profit from 4th generation
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Mathias Prokop, MD: Cardiac CT- what comes after the
slice race?
May 16, 2008- 9:10
Stanford Radiology 10th Annual Multidetector CT
Symposium
CT Perfusion
Vendor Approaches
• Spiral / shuttle mode:
bidirectional table movement
(Siemens / GE)
• Wide detectors
(Philips / Toshiba)
• Jog mode - switch between two positions
(Philips)
CT Perfusion
Shuttle Mode
Advantages:• Larger coverage
• Detector size not limitin
Courtesy of University Erlangen / Erlangen, Germany
Disadvantages:
• Patients moves
• Limited temporal
resolution
• Cardiac difficult
CT Perfusion
Stationary Mode
Advantages:
• Patients stable
• Hi h tem oral resolution
Courtesy of P. Rogalla, Charite, Berlin
• Cardiac possible
Disadvantages:
• Coverage limited by
detector size
Dual Energy
Vendor Approaches
Dual source
Siemens
Ra id kV switchin
GE
Split Detector
Philips
Klinikum Dortmund
Dual source technology
140kVp / 80 kVp
Dual Energy
Do we need it ?
Potential Applications:
• Stone differentiation
• Virtual recontrast ima es
Proven application
• Automated bone removal
• Iodine maps
Myocardial perfusion
Lung perfusion
Tumor enhancement
Low kVp imaging
may be an
alternative
Summary
8/12/2019 0910 Prokop Cardiac CT
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Mathias Prokop, MD: Cardiac CT- what comes after the
slice race?
May 16, 2008- 9:10
Stanford Radiology 10th Annual Multidetector CT
Symposium
MDCT Implementation
Summary
4th Generation Scanners• Mature technology for body imaging (=64-slice)
• Decent technolo for erfusion
• Advanced technology for cardiac
• Best cardiac scanners
• Perfusion CT still very radiation intense,
few proven indications