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‫بسم هللا الرحمن‬
‫الرحيم‬
Multi-Slice CT
Short Notes On Clinical Application
Dr Mohamed El Safwany, MD.
Physical Principles
of Multi-Detector
CT
Intended learning outcome

The student should learn at the end of this
lecture principles of multidetector CT.

Multiplied Computed Tomography (MSCT) was introduced in
the field of radiology in 1998 resulting in revolution of
imaging and addition of a new clinical applications.

The benefits of multi-detector CT relative to single-section CT
are significant.

The examination can be done with thinner sections, and much
faster resulting in improved resolution and reducing the
motion artifacts.

MDCT can cover a distance 8 times longer than single-slice
CT.
There are 2 main differences between
ordinary spiral CT machines and
MDCT :1- It allows the acquisition of multiple
axial images with a single gantry
rotation.
2- It has shorter gantry rotation period
making it much faster.
Scanning Speed
 MDCT
scanners have gantry
rotation period of 0.5 sec, twice the
speed of most conventional helical
scanners.
 Therefore, a MDCT scanner with 4
data channels is up to 8 times faster
than a conventional single-slice CT
scanner.
Clinical Applications

Multisection CT aquires changes in the planning
and staging of patient examinations. The
scanning time is reduced for most examinations,
requiring adjustments in the administration of
intravenous contrast material. The amount of
contrast material can be reduced, and different
vascular phases can be better visualized. Thinsection scanning allows production of highquality MPR images

Coronal reformation image of the right
temporal bone created from an axial
multisection
(a) Coronal MPR image clearly shows a pin
penetrating the posterior subtalar joint
(arrowheads). (b) Sagittal MPR image clearly
shows secondary degenerative changes (arrows).
Streak artifacts are remarkably mild given the
large amount of steel.

Thin-section CT of the hip (a, b) Coronal (a)
and curved oblique sagittal (b) reformation
images show fine detail. (c) Lateral surfacerendered image shows the acetabulum and
femur together.

(a) Coronal maximum-intensity projection
image shows the sacrum with metal appliances.
(b) Curved reformation image shows the
sacroiliac joint surfaces and bone grafts (arrow).

(a) Sagittal image shows that the multisection
acquisition will avoid dental hardware and the
associated artifacts. (b, c) Coronal (b) and
sagittal (c) reformation images show
mucoperiosteal thickening.

Bone Tumors

(a) Sagittal reformation image
shows excellent bone detail and
the outline of the subarachnoid
space. (b, c) Corrected-axis
MPR image (b), which was
obtained along the dashed line
in a, has the same spatial
resolution as an original axial
image

Duodenal carcinoma. (a-c) Axial (a), coronal
(b), and sagittal (c) images show a dilated
common bile duct (I) and a duodenal neoplasm
(arrows). (d, e) Lateral arterial-phase (d) and
anterior venous-phase (e) maximum-intensity
projection images show normal vessels.

Bilateral carotid artery stenosis.
Coronal maximum-intensity
projection image from CT
angiography performed from
the arch to the skull base (1.0mm section thickness, 19-cm
longitudinal coverage, 0.5-mm
longitudinal reconstruction
interval) shows severe stenosis
of the left internal carotid artery
(arrow).

Renal artery stenosis in a hypertensive patient
imaged with CT angiography

Renal Angiography

Endovascular repair of an aortic
aneurysm with stent-grafts

Virtual Endoscopy

CT coronary angiography is becoming feasible
with the availability of faster multisection
imaging.

Multisection CT is superior to single-section helical CT
for nearly all clinical applications. The superior speed of
the former can be used to improve the temporal,
spatial, and contrast resolution of the images. In
addition, multisection CT shows promise for clinical
applications that were limited or impossible with singlesection helical CT, such as cardiac imaging, organ
perfusion studies, and examinations of multiple
vascular phases. It also brings isotropic imaging into the
CT domain. CT has reached the brink of a new era.
Text Book


David Sutton’s Radiology
Clark’s Radiographic positioning and techniques
Assignment

Two students will be selected for assignment.
Question

State difference between single and
multidetector CT?
Thank You
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