1. بسم الله الرحمن الرحيم

2. Multi-Slice CT Short Notes On Clinical Application
Dr Mohamed El Safwany, MD.

3. Physical Principles of Multi-Detector CT

4. Intended learning outcome
The student should learn at the end of this lecture principles of multidetector CT.

5. 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.

6. 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.

8. 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.

10. 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. Thin-section scanning allows production of high-quality MPR images

11.  Coronal reformation image of the right temporal bone created from an axial multisection

12. (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.

13. Thin-section CT of the hip (a, b) Coronal (a) and curved oblique sagittal (b) reformation images show fine detail. (c) Lateral surface-rendered image shows the acetabulum and femur together.

14.   (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).

15. (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.

16. Bone Tumors

17. (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

18. 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.

20. Bilateral carotid artery stenosis
  Bilateral carotid artery stenosis. Coronal maximum-intensity projection image from CT angiography performed from the arch to the skull base (1.0-mm section thickness, 19-cm longitudinal coverage, 0.5-mm longitudinal reconstruction interval) shows severe stenosis of the left internal carotid artery (arrow).

21. Renal artery stenosis in a hypertensive patient imaged with CT angiography

22. Renal Angiography

23. Endovascular repair of an aortic aneurysm with stent-grafts

24. Virtual Endoscopy

25. CT coronary angiography is becoming feasible with the availability of faster multisection imaging.

26. 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 single-section 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.

27. Text Book David Sutton’s Radiology
Clark’s Radiographic positioning and techniques

28. Assignment
Two students will be selected for assignment.

29. Question
State difference between single and multidetector CT?

30. Thank You