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MAGNETIC RESONANCE IMAGING. 2003 Noble Prize Laureates in Physiology or Medicine Paul C. Lauterbur and Peter Mansfield. Noble Prize. 6 October 2003 Press Release

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magnetic resonance imaging

MAGNETIC RESONANCE IMAGING

2003 Noble Prize Laureates in Physiology or Medicine

Paul C. Lauterbur and Peter Mansfield

noble prize
Noble Prize

6 October 2003

Press Release

The Nobel Assembly at Karolinska Institute has today decided to award The Nobel Prize in Physiology or Medicine for 2003 jointly to

Paul C. Lauterbur and Peter Mansfield

for their discoveries concerning

“magnetic resonance imaging”

for their discoveries concerning magnetic resonance imaging
“for their discoveries concerning magnetic resonance imaging”

Paul C. LauterburPeter Mansfield

½ of the prize USA ½ of the prize United Kindom

University of Illinois University of Notingham

Urbana, IL, USA. United Kingdom.

b. 1929 b. 1933

paul c lauterbur
Paul C. Lauterbur
  • born May 6, 1929 in Sidney, Ohio, USA.
  • 1951 B.S. in Chemistry, Case Institute of Technology, Cleveland
  • 1962 Ph.D. in Chemistry, University of Pittsburgh, Pennsylvania
  • 1969-85 Professor of Chemistry, Radiology, New York University at Stony Brook
  • 1985-90 Professor, University of Illinois, College of Medicine at Chicago
  • 1985-Professor and Director, Biomedical Magnetic Resonance Laboratory, University of Illinois, College of Medicine at Urbana, IL.
peter mansfield
Peter Mansfield
  • born October 9, 1933.
  • 1959 B.Sc. Queen Mary College, University of London
  • 1962 Ph.D. Physics, University of London
  • 1962-64 Research Associate, University of Illinois.
  • 1964 Lecturer, University of Nottingham.
  • 1968 Senior Lecturer, University of Nottingham.
  • 1972-73 Senior Visitor, Max Planck Institut für Medizinische Forschung, Heidelberg
  • 1979- Professor, University of Nottingham.
history of mri
History of MRI
  • Late 1800’s
  • November 5, 1895. William Roentgen discovered X-rays.
  • Roentgen discovered that:
  • X-rays travel in straight lines,
  • could not be refracted or reflected
  • did not respond to magnetic or electric field.
  • February, 1896, X-rays were being used clinically in the United States.
history of mri7
History of MRI
  • In the 1930’s, a physics phenomenon was discovered, called nuclear magnetic resonance or NMR.
  • Felix Bloch, working at Stanford University, and Edward Purcell, from Harvard University, discovered NMR.
  • In NMR nuclei were placed in a magnetic field, they absorbed energy in the radiofrequency range of the electromagnetic spectrum, and re-emitted this energy when the nuclei transferred to their original state.
history of mri8
History of MRI
  • This phenomenon was termed NMR as

follows:

  • "Nuclear" as only the nuclei of certain atoms

reacted in that way;

  • "Magnetic" as a magnetic field was required;
  • "Resonance" because of the direct frequency

dependence of the magnetic and

radiofrequency fields.

history of mri9
History of MRI
  • For their discovery of NMR Bloch and Purcell were awarded the Nobel Prize for Physics in 1952.
  • Use of NMR to investigate the chemical composition and physical structure of matter.
  • Relaxation times, T1 and T2.
  • T1: Time taken by nuclei in test samples to return to their natural alignment
  • T2: Duration of the magnetic signal from the sample.
history of mri10
History of MRI
  • In 1970s Raymond Damadian, proposed that each tissue in the body has a different relaxation time, but cancerous tissue has an abnormally long relaxation time.
  • He believed that the NMR could be used as an “external probe for the internal detection of cancer”
  • Damadian presented first commercial NMR scanner at the annual meeting of the American Roentgen Ray Society in 1980.
history of mri11
History of MRI
  • Paul C. Lauterbur determined the origin of the radio waves by analysis of their characteristics.
  • Discovered the possibility to create a two-dimensional picture by introducing gradients in the magnetic field.
  • In 1972, obtained the first MRI.
history of mri12
History of MRI
  • Pater Mansfield further developed the utilization of gradients in the magnetic field.
  • Signals could be mathematically analyzed.
  • Showed how extremely fast imaging could be achievable.
  • In 1976, he and his colleagues created the first MRI of a human body part, a finger.
what is an mri
What is an MRI?
  • Magnetic Resonance Imaging (MRI) :safe and noninvasive test.
  • Diagnostic technique :uses strong magnetic field and pulses of radio waves.
  • Produces pictures of structures inside the body.
  • Images :slices of an organ or part of body.
  • MRI’s computer: 3-D images.
how it works
How it works?
  • Body :strong magnetic field.
  • Machine uses :strong magnetic field and pulses of radio waves.
  • Machine creates an image :how hydrogen atoms react.
  • Usually images are created as single slices of organs or structures.
  • MRI computer combine them to give a 3 D image.
using our body s magnets
Using Our Body’s Magnets
  • Because of predictions from physics and math we know there are very weak magnets in all living tissues
  • These magnets are atoms with unpaired numbers of protons and electrons like hydrogen 1H
  • There are billions and billions of hydrogens in your body
using our body s magnets16
Using Our Body’s Magnets
  • 1H do not have a matched pair of neutrons and protons
  • When atomic nuclei do have perfectly matched neutrons and protons, these always arrange in pairs and rotate in opposite directions to one another
  • With 1H, there is no match and there is a nuclear spin and slight + charge
using our body s magnets17
Using Our Body’s Magnets
  • One way is to stick these very weakly magnetic tissues in a gigantic, strong MAGNET and see what happens!!!!!!
  • This is the principle of Magnetic Resonance Imaging, (MRI) used in research and diagnostic radiology today!!!!!!!!!
slide18

Protons produce a small magnetic field

A moving electric charge produces a magnetic field

Protons have a positive charge

Protons spin

slide19

No external field…

Randomly aligned

slide20

External field…

Aligned with field

slide21

Some protons align with the field…

Some protons align against the field…

Protons continually oscillate – always a slight excess aligning with field

Aligning with field – slightly lower energy state

slide22

Protons Wobble

Spinning protons wobble about the axis of the external field

Frequency of precession = Resonance Frequency

Depends on strength of magnetic field

slide23

Protons ‘jump’ to a higher state

RF Pulse

Apply RF pulse at resonance frequency

Protons absorb energy

slide24

What goes up…

…must come down

Energy is re-transmitted as RF signal

slide25

MRI Signal

Summary

mri hardware scanner
MRI HardwareScanner

Liquid Helium Cooled

1.5 Tesla Solenoid Magnet

Radiofrequency

Transmitter/Recieiver

Coil

Patient Platform

mri of the brain sagittal
MRI of the Brain - Sagittal

T1 Contrast

TE = 14 ms

TR = 400 ms

T2 Contrast

TE = 100 ms

TR = 1500 ms

Proton Density

TE = 14 ms

TR = 1500 ms

mri of the brain axial
MRI of the Brain - Axial

T1 Contrast

TE = 14 ms

TR = 400 ms

T2 Contrast

TE = 100 ms

TR = 1500 ms

Proton Density

TE = 14 ms

TR = 1500 ms

slide32

Contrast in MRI

T1

T2

Gadolinium

The Whole Brain Atlas:http://www.med.harvard.edu/AANLIB/

laser polarized gas lung imaging
Laser Polarized Gas Lung Imaging

Chronic Obsructive Pulmonary Disease

Healthy Volunteer

advantages of mri
Advantages of MRI
  • Diagnosing multiple sclerosis (MS)
  • Diagnosing tumors of the pituitary gland and brain.
  • Diagnosing infections in the brain, spine or joints
  • Visualizing torn ligaments in the wrist, knee and ankle
advantages of mri36
Advantages of MRI
  • Visualizing shoulder injuries
  • Diagnosing tendonitis
  • Evaluating masses in the soft tissues of the body
  • Evaluating bone tumors, cysts and bulging or herniated discs in the spine
  • Diagnosing strokes in their earlieststages.
disadvantages of mri
Disadvantages of MRI
  • Not for everybody.
  • machine makes a tremendous amount of noise.
  • require patients to hold very still for extended periods of time.
  • Orthopedic hardware (screws, plates, artificial joints) in the area of a scan can cause severe artifacts (distortions) on the images.
  • very expensive.
future of mri
Future of MRI
  • Very small scanners.
  • Functional brain mapping.
  • Ventilation dynamics of the lungs through the use of hyperpolarized helium-3 gas.
  • Image strokes in their earliest stages.
  • Limitless future
slide39

Laser Polarized Xenon MRIFunctional Brain Imaging

Map of Blood Flow in the Rat Brain

functional brain imaging
Functional Brain Imaging
  • Blood Oxygenation Affects Contrast
  • Metabolism uses oxygen
  • Contrast Reveals regions of oxygen consumption

University of Minnesota

http://www.cmrr.drad.umn.edu/highlight/index.html

laser polarized gas images
Laser Polarized Gas Images

University of Virginia

sources used
Sources used:
  • http://www.nobel.se/medicine/laureates/2003/
  • http://inventors.about.com/
  • http://www.bae.ncsu.edu/
  • http://www.isbe.man.ac.uk/
  • www.cmrr.drad.umn.edu/
  • Slides provided by Dr. Vankley.