VC Normal

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64-Channel CT Scanning Six months clinical
experience of thoracic, angiographic, cardiac,
abdominal, musculoskeletal and neurological
Imaging.
J Rydberg, MD K Sandrasegaran, MD A C
Douglas-Akinwande, MD J L Rankin, RT R H
Choplin, MD K A Buckwalter, MD Dean Maglinte,
MD Darel Heitkamp, MD Shawn Teague, MD.
INDIANA UNIVERSITY DEPARTMENT OF RADIOLOGY
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How to read the exhibit
This exhibit consists of 61 pages. They
are arranged in columns from left to right.
This exhibit can also be viewed on the web
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www.indyrad.iupui.edu (Click MultiSlice CT
Lectures)
Jonas Rydberg, M.D., jrydberg_at_iupui.edu
Theory/Technical
Cardiac applications
Conclusions
Other clinical applications
Teaching objectives

• Review basic principles of a 64-channel scanner.
• Compare 64-channel to other multichannel CT
  scanners.
• Overview of 64-channel CT scanning in clinical
  practice.

3
Conclusions

• The 64-channel CT is very powerful for all
  applications.
• The system is very reliable and is technologist
  friendly.
• Isotropic viewing is an integral part of image
  review.
• Coronary CTA has become very reliable.
• Improved dose efficiency is noted.

Whole-body isotropic imaging is like having a
walk-through gantry!
The Department of Radiology at Indiana University
School of Medicine is a CT beta test site for
Philips Medical Systems.
4
Installation at Indiana University
Site University Hospital, Indiana University,
Indianapolis Scanner Brilliance 64 Scanner
type 64-channel Vendor Philips Medical
Systems Inc FDA approval December 2004
Installation April 2005 First clinical
patient April 7, 2005 Clinical experience
2400 patients
The Brilliance CT scanners have a common platform
for scanning and postprocessing. They include 6-,
10-, 16-, 40- and 64-channel scanners. The
Brilliance 64 is a further development of the
Brilliance 40 with main difference being the
detector array configuration and the electronics
package (DAS). Our Brilliance 40 was given a
one-day hardware upgrade when the detector
package was switched from the 40-channel to the
64-channel configuration.
New detector package X-ray tube
5
Brilliance 64 - detector array configuration
The Brilliance 64 CT scanner is a 64-channel
scanner with a 40 mm wide detector array. The
scanner has a 64-channel digital acquisition
system (DAS) with capability to acquire up to 160
back-to-back 0.67 mm thin slices per second. All
applications are possible with this scanner. The
Brilliance 64 has the same gantry platform as the
Brilliance 40.
6
Three levels of multi channel CT development
tested at IU
Year of introduction, number of channels and
detector array configuration
1998 4-channel CT (Mx8000 Quad, Philips Medical
Systems)
5.0
2.5
1.5
1
1
1.5
2.5
5.0
2002 16-channel CT (Mx8000IDT16 / Brilliance 16,
Philips Med Systems)
16 X 0.75 mm
4 X 1.5 mm
4 X 1.5 mm
2003 40-channel CT (Brilliance 40, Philips Med
Systems)
40 X 0.625 mm
6 X 1.25 mm
6 X 1.25 mm
7
Brilliance 40 - detector row configuration
Brilliance 40 is the predecessor of the
Brilliance 64. The 12 outermost detector rows on
the Brilliance 40 are 1.25 mm wide while the
innermost 40 detector rows are 0.625 mm wide. The
Brilliance 40 is limited to 40 electronic
channels.
40 X 0.625 mm
6 X 1.25 mm
6 X 1.25 mm
0.625
1.25
0.625
8
Brilliance 64 - detector row configuration
Brilliance 40

40 X 0.625 mm
6 X 1.25 mm
6 X 1.25 mm
Brilliance 64
64 X 0.625 mm
Brilliance 64 has 64 detector rows and 64
electronic channels
9
Dose efficiency
Contrary to what many believe is that the dose
efficiency increases with increased number of
digital channels. The 64-channel scanners with 40
mm beam collimation capacity have the highest
dose efficiency. The increased dose efficiency is
directly related to the reduction of penumbra
radiation.
Comparison (CTDI volume) between scanners
0.7 1.2 mm slice width
10
5 mm slice width
Courtesy Philips Medical Systems, Cleveland, Ohio.
11
Image load / overload

• Large number of slices - A 64-channel CT scanner
  makes it possible to produce a very large number
  of thin slices. It is not uncommon for exams to
  contain 2000-6000 images.
• Most slices are noisy - It is equally important
  to realize that, for most applications, the thin
  slices provide the information to create
  multiplanar reformations and the original slices
  are not reviewed.
• Create an image handling paradigm - The keys to
  successful scanning reconstruction post
  processing - diagnostic review is to create a
  workflow paradigm where the isotropic-volumetric
  images are converted into a limited number of
  diagnostic images.
• Guidelines
• Anticipate the need for 2D and 3D
  reconstructions.
• Routinely save the 2D and 3D images to PACS.
• Consider discarding the original thin source
  images.

12
Brilliance 64 - Scanner workflow for abdominal
CT
Reformats
Slab-MIP
Scan 64 X 0.625 mm Reconstruct 0.9 mm
_at_ 0.45 mm Post processing See table on right
Post proc.
Cor
Sag
Ax
Cor
Sag
Routine A P
4 _at_ 3
4 _at_ 3
2_at_3spine
Routine A
4 _at_ 3
4 _at_ 3
2_at_3spine
Routine P
4 _at_ 3
4 _at_ 3
4 _at_ 3
Dual L arterial
4 _at_ 3
4 _at_ 3
10 _at_ 3
4 _at_ 3
4 _at_ 3
Portal-venous
Dual P precontrast
4 _at_ 3
pancreatic
3 _at_ 3
3 _at_ 3
3 _at_ 3
10 _at_ 3
10 _at_ 3
portal-venous
4 _at_ 3
4 _at_ 3
Renal stone
3 _at_ 2
3 _at_ 2
Renal
4 _at_ 3
4 _at_ 3
Adrenal
3 _at_ 2
3 _at_ 2
Send to PACS All images created according to
table. DO NOT send to PACS The thin source
images 0.9 mm _at_ 0.45 mm
CT-entero
4 _at_ 4
4 _at_ 4
4 _at_ 4
CTA aorta pre C
2 _at_ 2
post C
2 _at_ 2
10 _at_ 3
Renal donor pre C
4 _at_ 3
4 _at_ 3
arterial
2 _at_ 2
10 _at_ 3
4 _at_ 3
4 _at_ 3
4 _at_ 3
nephrographic


Aorta lower extr. CTA
2 _at_ 1.5
Coronal 10_at_3 1. Abd/pelvis 2. Thighs 3.
Run-offs
Sag 2_at_1 Abd aorta
Cases marked with
- send thin slices to dedicated workstation for
more postprocessing
13
Noisy thin slices of limited diagnostic value
Thin slices have no inherent diagnostic value
unless one is looking at very tiny structures.
The 1 mm thick slice on the left does not add
anything compared to the 5 mm thick slice on the
right with much better signal-to-noise.
1 mm thin noisy source image
5 mm thick diagnostic image
The 0.8 mm thin source image on the left does not
add any diagnostic information. But, a stack of
0.8 mm axial thin slices allow for high quality 4
mm thick coronal reformats as seen on the right.
Increased signal/noise depicts the liver mass
(white arrow)
4 mm thick diagnostic image
0.8 mm thin noisy source image
14
Variation in thickness of coronal reformats
Choice of slice thickness of reformats usually
matches the currently used thickness of routine
axial images. Strive for optimal signal to
noise. It is the image spacing that determines
the image load not image thickness. When saving
images in multiple planes, consider reducing the
amount of overlap in each plane, and thereby
reduce the total image load.
3 mm
2 mm
1 mm
4 mm
5 mm
7 mm
10 mm
Source images 0.9 mm thickness with
reconstruction increment of 0.45 mm (0.9 mm _at_
0.45 mm)
15
Surview planning - new paradigm
A new software tool Surview planning, Philips
Medical Systems, allow the CT tech to plan the
post processing (reformats and Slab-MIP) already
on the Surview, before the start of
scanning. Once the scan is completed
reconstruction into thin source images and all
postprocessing is executed automatically.
Example of pre-programmed postprocessing protocol
for routine CT abdomen-pelvis
View on scanner console prior to scanning
16
Routine abdomen-pelvis
Scanning 64 X 0.625 mm collimation
All routine postprocessing for CT of abdomen and
pelvis can be done at the CT scanner console.
Built in software like Surview planning may
facilitate the process.
Reconstruction from raw data
R e f o r m a t t i n g
Slice thickness 0.9 mm Recon Increment 0.45
mm
Sagittal 2_at_3 (bone window)
Axial 4_at_3
Coronal 4_at_3
160 slices
65 slices
40 slices
Total 1064 slices
Total slices to review 256
17
Routine chest-abdomen-pelvis
All routine postprocessing for CT of abdomen and
pelvis can be done at the CT scanner console.
Built in software like Surview planning may
facilitate the process.
Scanning 64 X 0.625 mm collimation
Reconstruction from raw data
R e f o r m a t t i n g
Slice thickness 0.9 mm Recon Increment 0.45
mm
Coronal 4_at_3
Coronal 4_at_3
Sagittal 2_at_3 (bone window)
Axial 4_at_3
Axial 4_at_3
62 84 slices
150 78 slices
40 slices
Total 1430 slices
Total slices to review 414
18
CTA abdominal aorta and run-offs
Post processing protocols at the scanner may
eliminate the need for dedicated 3-D
postprocessing on separate workstation. Post
processing at scanner console may save both time
and money.
Scanning 64 X 0.625 mm collimation
Reconstruction from raw data
R e f o r m a t t i n g
Slice thickness 0.9 mm Recon Increment 0.45
mm Diaphragm to feet Slices 2850
Additional Re-reconstruction from raw data with
soft filter and smaller FOV Knees to feet
0.9_at_0.45 Slices 1390
Axial 2_at_1.5
Cor Slab MIPs 10_at_3
Sag2_at_1
111
23
96
75 slices
841




Total 4240 slices
Total slices to review 1146 slices
19
CTA renal donor evaluation
Renal donor CT postprocessing can be done
partially at the scanner console. But, all types
of measurements and special views are better done
by dedicated postprocessing CT technologist on a
separate workstation.
Scanning 64 X 0.625 mm collimation
Reconstruction from raw data
R e f o r m a t t i n g
Pre 0.9_at_0.45 779 slices
Art 0.9_at_0.45 357 slices
Pre contr.
Arterial
Venous
Ven 0.9_at_0.45 592 slices
168 81 80 49 32 88 32 81
slices
Total 1728 slices
Total slices to review 611 slices
20
Thin source images not saved to PACS. Only
limited number of images from scanners reach PACS
and viewing stations.
large image flow
limited image flow
CT post processing technologist
16-channel
64-channel
Ne
Ch
Ab
Msk
One Philips workstation in each reading room (1.2
Terabyte non-redundant storage of source images)
PACS
21
Coronary CT with 64
Coronary angiography with 64 channel scanning has
further increased scan speed and increased
percentage of successful exams. A typical scan
time is down to 10 seconds which represents an
easy breath hold for most patients. Heart rates
above 60-70 bpm often yield diagnostic exams.
However, we routinely give nitroglycerin
sublingual and beta blockers iv prior to the exam
in order to optimize the scanning.
Key coronary CTA scanning parameters
0.90 mm
0.90 mm
0.45 mm
22
Comparison 4 -16 - 64 channel CT
DISPLAY BELOW Compare sets of volume rendered
images of coronary arteries from a Mx8000 Quad in
2001 (top), Brilliance 16 in 2003 (middle) and
Brilliance 64 in 2005 (bottom). Faster scans,
thinner section slices and isotropic voxels allow
for much improved image quality on the 64-channel
scanner. Note improvement on 64-channel scanner
of vessel depiction on fast moving underside of
heart (third column of images).
Name Mx8000Quad Brilliance 16 Brilliance
64 Year launched 1998 2002 2005 Type 4-chann
el 16-channel 64-channel Slice thickness 3.2
mm 0.8 mm 0.67 mm Pitch 0.38 0.2 0.2 Gantry
rotation time 0.50 sec 0.42 sec 0.40 sec Scan
time 27 sec 31 sec 10 sec
23
Mx8000 Quad
Brilliance 16
24
Brilliance 64
25
Vascular detail
64-channel CT gives improved depiction of the
major coronary arteries. But it also creates
ability to evaluate multiple branch vessels such
as
LAD
Acute marginals from RCA Diagonals from
LAD Obtuse marginals from circumflex Septal
branches from LAD
RCA
Cx
LAD
LAD
26
LAD occlusion
48 year old man with chest pain. Conventional
arteriography (right) shows multiple high degree
occlusions on left anterior descending artery.
Matching appearance on coronary CTA volume
rendering (below left) and curved reformat (below
right).
Coronary CTA with 64-channels yields 1. Positive
predictive value 66-93 2. Negative predictive
value 93-98
27
Bypass graft imaging
Patient A - VR image demonstrates right internal
mammary artery (yellow arrows), left internal
mammary artery (LIMA) (blue arrows), and venous
bypass graft (pink arrows) which was imaged as
part of a routine pulmonary vein study. Patient
B - Curved MPR image (left) and VR image (right)
demonstrate a LIMA graft (yellow arrows)
anastomosis to the LAD (blue arrow) and a venous
graft (pink arrows) crossing over to an obtuse
marginal branch.
Patient A
Patient B
28
Bypass graft aneurysm
66 year old man S/P CABG. Venous bypass graft to
OM branch demonstrates a focal aneurysm (yellow
arrows) which contains mural thrombus (pink
arrows) resulting in a relatively normal contrast
enhanced lumen. The volume rendered image
(right) only displays the lumen thus missing the
thrombosed portion of the aneurysm. Coronary
catheterization also only looks at the lumen and
thus also would likely miss the finding.
29
Long coverage with ECG gating
Triple rule-out CT 64-channel scanners with
wide detector array and fast gantry rotation can
cover the entire chest in one breath hold. This
fast one breath-hold scan allows for complete
evaluation of 1. Pulmonary arteries 2.
Coronary arteries 3. Thoracic aorta
To cover the chest within one breath hold a low
pitch (about 0.2) in combination with high table
speed (about 20 mm/sec) is needed.
30

• Triple rule-out CT in 42-year old man showed
• 0. No pulmonary emboli
• Ascending aortic aneurysm
• Small aortic dissection
• 3. Arterial anomaly - no main left coronary
  artery

1.
2.
16 sec scan
3.
1.
31
Coronary Imaging
A
B
C
LAD
1st Obtuse Marginal
Circumflex
D
50 year old male with chest pain. Images (A
through C) are curved multiplanar reformatted
images showing normal coronary arteries. Image
(D) is a MIP image of the RCA which shows its
origin with proximal portion and branches. This
patient has a normal study.
RCA
32
Abdominal CT with 64
CT of abdomen-pelvis and chest-abdomen-pelvis
benefit from scanning with narrow detector rows
and reconstruction into thin source images
(isotropic voxels). The source axial images
should be 1 mm or less in thickness. Viewing of
exams benefits from coronal and sagittal
reformats. Image at left illustrates
eventeration of left hemidiaphragm in 72-year old
male. The coronal view clarly shows the position
of both hemi diaphragms. Thickness of source
images 0.9 mm Thickness of images to view 4.0
mm
33
Uretero-pelvic junction obstruction
33-year old man with right flank pain. Ultrasound
exam showed right hydronephrosis. A. Coronal
reformat in arterial phase shows early
bifurcation of right main renal artery to
superior (yellow arrowhead) and inferior (red
arrowhead) branches. Renal pelvis (black arrow)
is distended. B. Coronal reformat in delayed
phase shows contrast excreted into renal pelvis
(black arrow) which is obstructed by crossing of
inferior renal artery branch (black arrowhead).
C. MIP image of delayed phase shows an IVU type
picture of the uretero-pelvic junction (UPJ)
obstruction (dashed arrow), no filling of right
ureter but normal filling of left ureter. UPJ
obstruction resolved after surgical repositioning
of inferior renal artery branch.
34
Virtual colonoscopy
76 year old female with unexplained lower GI
bleed. Failed colonoscopy. Virtual colonoscopy
shows adenocarcinoma in proximal ascending colon
adjacent to the ileocecal valve.
The endoluminal view (center) and fillet view
(right) show cancer (yellow arrows), ileocecal
valve (blue arrows) and lumen stricture (white
arrow). Note that the stricture of the lumen
cannot be appreciated on the fillet view since
the whole colon has been dissected open along its
longitudinal axis and thereby opening up the
stricture.
35
Crohns disease
36 year old female with perirectal abscess (white
arrowheads) with a component (black arrowheads)
extending above levator ani muscle. The rectum
wall (arrow) is thickened by colitis. Evaluation
facilitated by coronal reformats.
Scan 64 X 0.625 mm Source images 0.9 _at_ 0.45
mm Reformats 4 mm thick
36
CT enteroclysis and vasculitis
CT enteroclysis Scanning 64 X 0.625
mm Recon 0.9 mm _at_ 0.45 mm Reformats (images to
view) 4 mm _at_ 3 mm - Axial - Coronal -
Sagittal
CT enteroclysis with water as enteral contrast
media in 27 year old female presented with
chronic diarrhea and anemia. Prior history
included systemic lupus erythematosis. Coronal
reformat shows diffuse smooth small bowel wall
and fold thickening (arrows). Small bowel biopsy
showed vasculitis.
37
Chest CT with 64
Routine Chest CT Protocol
Detector Configuration 64 x 0.625 mm Source
images 0.9 mm _at_ 0.45 mm Scan Direction Superio
r to Inferior Above Apex thru
Diaphragms Slice Thickness 4 mm Slice
Increment 3 mm Pitch 0.98 Gantry Rotation
Time 0.75 sec mAs 300 kVp 120 Contrast
100 mL Isovue 370 Injection Rate 2
mL/sec Delay Time 50 sec Routine Post
Processing 4_at_3 mm Coronal MPRs
38
Mediastinal mass
66 year old female with metastatic breast cancer.
Heterogenous enhancing soft tissue mass encases
the structures of the anterior mediastinum and
left hilum. The left lower lobe is collapsed and
the left pulmonary artery branches are narrowed.
At Indiana University, cases of suspected or
known malignancy are protocoled as routine chest
CT with contrast media unless the patient has a
contraindication to contrast media.
39
Chest wall mass
Added overview with coronal reformats
25 year old female with synovial cell sarcoma of
the left anterior chest wall, pretreatment study.
Enhancing left-sided chest wall mass with
internal low density necrosis (yellow arrows) and
areas of calcification (pink arrows). There is
mass-effect on the chest wall.
40
Polyp in mainstem bronchus
A
C
D
71 year old male with endobronchial carcinoid.
Coronal MPR image (A) shows a polypoid mass in
the distal left mainstem bronchus (yellow arrow).
Coronal minimum intensity projection (MinIP)
image (B) shows a similar appearance. Axial
source CT image (C) verifies lesion in orthogonal
plane. Virtual bronchoscopy image (D) looking
distally from the mid left mainstem bronchus
shows the polypoid mass (pink arrow).
B
41
CTA with 64

• Many applications in CTA can be done successfully
  with 16-, 32- and 40-channel scanners.
• A difference with 64-channel scanning has been
  seen in the following areas of CTA
• Coronary CTA and single short breath-hold
  scanning
• Thoraco-abdominal aorta CTA with ECG gating
• Carotid CTA to minimize venous influx
• Aorta runoff CTA to maximize vessel
  opacification
• Complete vascular evaluation of the chest
  (Triple-rule out)
• Minimize the use of intravenous contrast media
  for CTA

42
Subclavian artery pseudoaneurysm
22-year old man with stab injury to upper left
chest, subsequently developed pulsating mass. CTA
performed with left arm up and right arm down to
reduce beam hardening through upper chest. Bolus
triggering at 150HU in proximal descending aorta.
Triggering level
Scan range
43
Perpendicular reformats show arterial connection
from subclavian artery to pseudoaneurysm (red
arrows).
Volume rendered overview
Venous fistula identified (blue arrow)
Early filling of proximal subclavian vein (1) and
no filling of more distal subclavian vein (2)
indicated venous fistula to pseudoaneursym.
1
2
44
Finer detail in volume rendering
Scanning with 64 x 0.625 mm detector
configuration allows for post processing with
finer detail depiction of vessels and metal in 3D
images. Zenith stentgraft in same patient
examined with 6-channel scanner(left) and
64-channel(right). Note left renal artery passing
through wire frame (yellow arrow).
2003
2005
6-channel scanner
64-channel scanner
45
ECG gating with long coverage
44 y/o woman with family history of AAA. Complete
survey of aorta and iliac arteries requested. ECG
gated CTA with total scan time of 24 seconds.
IV contrast media Isovue 300 Volume 150
ml Injection rate 4.5 ml/s
Key scanning parameters
46

• Our routine post processing of ECG gated thoracic
  aorta includes
• diameter measurements at five locations
• Aortic valve
• Ascending at main pulmonary artery
• Arch at left subclavian artery
• Descending at main pulmonary artery
• Diaphragm

47
CTA with low volume contrast media
64-channel CT allows for CTA with low volume
intravenous contrast media. Saline push is
recommended. Automatic triggering software
started scan at 150 HU attenuation in the aorta
after 26 seconds delay (below left). Total scan
time for abdominal aorta was 6 seconds. Note the
very fine detail in volume rendering despite the
very fast scan times. Also note endoleak (yellow
arrows) next to the Aneurex stentgraft.
Contrast media 50 ml Isovue 300 Injection rate
3.5 ml/sec Saline push 40 ml at 3.5
ml/sec Pitch 1.11 Coverage 500
mm Scan time 6 sec
26 sec
48
AAA stent and renal artery stents
Metal within metal renal artery stents within
aortic stent graft Despite the multitude of
stainless steel curved reformatted images in 90
degrees perpendicular planes allow for complete
visualization of interior aspects of bilateral
renal artery stents as well as renal
arteries. Note thrombus formation on inside of
aortic stent (arrows)
Curved coronal reformat
Curved axial reformat
49
Long CTA coverage
Complex postoperative states can easily be
depicted with the help of 64-channel CT. A/
Midaortic occlusion B/ Aorta to iliac by-pass
graft C/ Aorto fem-fem graft D/ Occluded
subclavian to fem. graft E/ Occluded right EIA
stent F/ Occluded fem-fem graft
D
B
A
E
C
F
50
Neuro with 64
Routine helical volumetric scanning
Volumetric helical scanning can be implemented as
a routine protocol. It allows for either
standardized reformatted images or interactive
evaluation on workstation at time of reading.  
Scanned helical Reconstructed into 430 source
images 0.67 mm _at_ 0.33 mm Reformatted into 4 mm _at_
3 mm in three planes
51
Intradural mass - CT myelography
58 year old man with history of abdominal tumor
presenting with bilateral lower extremity
weakness. Post myelogram CT demonstrates a well
circumscribed intradural mass at T8-9 which has a
broad based dural attachment and faint
intralesional calcifications (arrows).
Detector configuration 64 x 0.625 mm Scan
length 62 cm Scan time 22 sec
52
Carotid artery repair
78 year old female with history of left carotid ar
tery repair presents with swelling/mass 
and intermittent pain on the left side of her
neck. Question of extravasation or
pseudoaneurysm. VR and MPR show complex vascular
anatomy. The vascular  graft begins at the 
anterior  medial aspect  of  the  left 
subclavian  artery (yellow arrow).  It
then extends  superior posteriorly and anastomoses
 with the left external (red arrow) and internal
(arrow head) carotid arteries.  There is no
contrast extravasation or pseudoaneurysm.
53
Carotids - no venous contamination
Carotid CTA with 64-channel scanning can be done
with no or minimal venous contamination. A table
speed of 56 mm/sec allows for a scan coverage of
37 cm in less than 8 seconds.
Left internal carotid artery High degree stenosis
Lat
AP
54
Lumbar spine hardware
64 y/o female with history of laminectomy at
L4-L5 and posterior fixation with transpedicular
screws presents with low back pain. Thin slice
technique with low pitch and adequate power most
of the time will yield good visualization of
bones, hardware and soft tissues. Note the
paucity of artifacts around the hardware. The
neural foramina (yellow arrows) are well
visualized despite the presence of metal
hardware. Soft tissue window allow visualization
of nerve roots
55
Musculoskeletal with 64
Advantages to 64-channel imaging include the
following - Superb anatomic coverage -
Excellent image quality - No compromise in scan
technique (mAs or kVp) - Thin slice imaging
(0.67 mm) Pitfalls - Cone beam artifacts
worsen as detector arrays widen - Artifacts blur
edges and degrade multiplanar reformations -
Metal hardware accentuates artifacts Use of low
pitch settings is critical to avoid these
artifacts. Empirically, pitch 0.25 works well

56
Long coverage
Patient with distal tibial exostosis (arrow).
Scan of entire tibia (437 mms) completed in 31
seconds at pitch 0.296, 64 x 0.625 mm
collimation, axial reconstructions 0.9 mm _at_ 0.5
mm increments. Coronal multiplanar reformations
show minor valgus bowing of distal tibia (open
arrow), and remodeling of fibula (arrowhead).
Absence of anterior bowing best illustrated on
sagittal reformation.
coronal
sagittal
coronal
57
CT knee arthrogram
59 y/o man with knee pain
patellar cartilage defect
58
CT Knee Arthrogram 59 y/o man with knee
painSingle contrast arthrogram.0.67 mm _at_ 0.3
mm reconstruction interval.
coronal MPR
Degenerative free edge medial meniscus tear
Cartilage defects
sagittal MPR
sagittal MPR
59
Bilateral hip implants bilateral cup liner wear
Right, anterior to posterior

coronal
56-year old man. CT of hip implants, scanned 64 x
0.625, reconstructed 1.0 mm _at_ 0.5 mm. Multiplanar
reformations show asymmetric centering of head
components in acetabular cups indicating liner
wear. Erosion of medial acetabular wall (arrows)
and pseudomembrane formation () has occurred.
Similar findings on contralateral side with
additional bone stock loss of greater trochanter
(curved arrow).
Left
sagittal
coronal
60
Detailed fracture evaluation of shoulder
58 y/o woman with right shoulder pain after a fall
Radiograph shows fracture of anterior glenoid
(arrow) and incidental calcific tendonitis (open
arrow)
111 kg patient, scanned affected arm down,
unaffected arm up.
Sagittal and coronal multiplanar
reformations iIllustrate full extent of glenoid
fracture (arrows).
61
Comminuted homolateral LisFranc fracture
dislocation
short-axis MPR
Original acquisition 0.67 _at_ 0.3 mm. MPRs created
from this data set.
lateral metatarsal shift multiple comminuted
fractures
long-axis MPR
sagittal MPR
62
39 y/o woman with 1 year of pain and swelling in
the upper chest at the sternoclavicular joints.
Has chronic pustular rash of the hands and feet
(image below left). She has a diagnosis of
fibromyalgia.CT chest showed possible
abnormality in sternoclavicular joints.
Re-reconstruction of raw data with bone
parameters yielded HiRes coronal reformats of
sternoclavicular joints.
SAPHO syndrome
Routine chest protocol Detector configuration 64
x 0.625 mm Section thickness 0.9 mm _at_0.45
mm Kernel Soft tissue Axial reformat
4 mm
Re-reconstruction parameters Detector
configuration 64 x 0.625 mm Section thickness
0.67 mm _at_0.33 mm Kernel Sharp Coronal
reformat 2 mm
Original axial from chest scan
Pustular rash of foot
63
Summary
Summary of Key Concepts

• The 64 channel CT has improved spatial and
  temporal resolution and allows for faster imaging
• Increased dose efficiency
• Routine isotropic scanning and viewing
• Introduction of routine MPR and Slab-MIP viewing
• Improved coronary artery imaging
• ECG gating of whole chest in one breath hold scan
• Faster scanning longer coverage in one breath
  hold
• Faster scanning less usage of iv contrast media
• Faster scanning Carotid CTA less venous
  contamination