MRI Technique
The basic principles of the MRI technique.
MRI Technical Background
- Excitation
- Relaxation
Excitation
The hydrogen proton is the most common atom in our body and can be found in substances including water (body consists for > 70% of water) and fat. Hydrogen protons are electrically charged (H+) and may be regarded as little magnets with a north pole & south pole. This makes hydrogen protons susceptible to external magnetic fields.
Each proton rotates 360° around its own axis (like a spinning top) and has a positive and negative pole. In order to understand MRI technology, you need to be aware that each proton spins with a certain speed, the so-called Larmor frequency (fig. 2). Because of its spin, the proton continually changes ‘phase’ (each phase is a snapshot, as it were). The relevance of this phase of the proton will be explained later in the course.
Interested?
Learn everything about MRI Technique
Text & Illustrations
drs. A. van der Plas, MSK radiologist Maastricht UMC+
Sources:
- C. Westbrook et al; MRI in Practice. 2011
- R. Bitar et al; MR Pulse Sequences: What Every Radiologist Wants to Know but Is Afraid to Ask. Radiographics 2006.
- G.B. Chavhan et al; Diffusion-weighted Imaging in Pediatric Body MR Imaging: Principles, Technique, and Emerging Applications. Radiographics 2014.
- E.J. Blink; MRI principes. 2004
06/03/2015
(All the work (text, illustrations, visual elements) seen on this website is copyright by Radiology Expert.
It may not be used without written permission of Radiology Expert).