Portable Magnetic Resonance

Devices

NMR

A spinning magnet in a magnetic field will precess

Larmor frequency ω = γ BResonance – absorb energy

Radio frequency for nucleiEnergy decay, relaxation times

T1 spin-lattice T2 spin-spin

Task 1

Nuclear Magnetic Resonance

What are the basic principles?

MRI

Need spatial information to form imageMagnetic gradientsRF pulse sequencesPhase encoding

Conventional MRI

Uniform Magnetic field 1 part per million

Field gradients superimposed to perturb field in defined way spatial information

RF Pulse sequences image contrast combinations of relaxation times

Task 2

Magnetic Resonance Imaging

How did NMR develop into MRI?

What are the essential requirements?

Hospital MRI

Large - fills a roomExpensive to buy

~£1M

Expensive to run ~£100k p.a.

Hospital MRI

Superb imagesHigh resolutionMultipurpose

Idea – Portable!

Permanent magnetNatural inhomogeneities

(But not too much!)

Local relaxation times (0D)‘images’ (1D, 2D, 3D)

Portable MR

Small - suitcase?Cheap - ~£10’s thousandsTailored for specific

applications?

Task 3

Magnetic Resonance Imaging

Are there any uses for small (portable) MR devices?

Work out the design specifications You might require for these applications.

Task 4

Magnetic Resonance Imaging

How can we make it small?

Can you devise ways of meeting the design criteria of Task 3?

Task 5

Magnetic Resonance Imaging

Can you identify devices in whichothers have attempted to meetthe challenge?

Aachen

http://www.nmr-mouse.de/

                                                               

the MObile Universal Surface Explorer or the NMR-MOUSE®

Bernhard Blümich

http://www.aixnmr.com/

Berkeley

http://waugh.cchem.berkeley.edu/research/index.php?rescat=8

http://chemistry.berkeley.edu/Publications/news/spring2005/nmr.htm

Portable High-Resolution NMR Sensor