Physics of CT & MRI

Course Objects:

• To obtain Knowledge about the basic principles and physics of CT and MRI
• To familiarize the student with the working principles of CT and MRI
• To gain knowledge about the construction and the components of the equipment
• To develop the technical skills in image reconstruction techniques and identifying artefacts

Learning Outcomes:

• Students can acquire knowledge about the basic principles and physics of CT and MRI
• Able to know the construction, components and the function of each components
• Ability to reconstruct the CT and MRI images
• Ability to detect the artefact and to take necessary actions if found

Syllabus

Module-1:Introduction to CT & MRI:

History & Principles, Advantages & Disadvantages of CT & MRI, X-Ray vs CT,  CT vs MRI.

Module-2: Physics of CT:

Tomography, Tomography moment and types, Types of CT beams, Detectors efficiency and Detector types, Scintillation Detector, Xenon Gas detectors, Collimators Generations of CT, Hounsfield Units, Grey Scale, Concept of Windowing, WW, WL, Concept of Voxel, Pixel

Module-3: Physics of MRI:

Basics of magnetism, Types of magnetism:Ferromagnetism, Para magnetism, Super para magnetism, Diamagnetism, Superconductivity, strength of external magnet, Tesla unit, Concept of proton unit, Larmour Frequency, Concept of resonance

Module-4: MRI Instrumentation:

Basic instrumentation of Coils Gradient Coils, RF Coils: Surface coil, Pair Saddle Coil, Helmholtz Pair Coil, Bird, Cage Coil.

Module-5: MRI Pulse sequences

T1, T2, Proton Density, Spin Echo, Inversion Recovery, Gradient echo.

Module-6: CT & MRI Image Reconstruction

Image Reconstruction, Back projection, Filter Back projection, Iterative method, Analytical method, CT-Number, Storage - Floppy, hard disc, magnetic tape, optical disc. Fourier transformation, Half-Fourier.

Module -7: Artifacts of CT & MRI

CT-Metal artifacts, Steak artifacts, Beam Hardening artifacts & Ring Artifacts

MRI-Aliasing, Chemical shift, Motion, Point , Gibbs , Magic Angle , Slice overlap , Zipper , Array Processing , Coil Selection ,Susceptibility

Session Plan

Session 1

History and introduction to CT scan

IAEA introduction to CT

https://www.youtube.com/watch?v=l9swbAtRRbg

Session 2

Introduction to MRI

MRI principle

https://www.youtube.com/watch?v=bTLRs-hpe9g

Session 3

Advantages & Disadvantages of CT & MRI

Session 4

Data acquisition in CT

DAS

Session 5

Types of CT beam

Pencil Beam and Fan beam

https://www.youtube.com/watch?v=KhOCZsl28dg

Session 6

CT detectors, Scintillation detectors and gas filled detectors

Gemstone detectors https://www.youtube.com/watch?v=i41RHswjRMQ

Session 7

Generations of CT

First, second, third, fourth,

Session 8

EBCT and flat panel CT

EBCT

EBCT https://www.youtube.com/watch?v=E9vLclEQRtc