History Of MRI Flashcards
a noninvasive medical imaging technique that uses the interaction between radio frequency pulses, a strong magnetic field and body tissue to obtain images of slices/planes from inside the body.
Magnetic resonance imaging (MRI)
discovered the Rotating Magnetic Field in Budapest, Hungary.!This was a fundamental discovery in physics.
Nikola tesla,1882
The __ for measuring magnetic flux density or magnetic induction (commonly known as the magnetic field B) was named in Tesla’s honour at the Conférence Générale des Poids et Mesures, Paris in 1960.
SI unit tesla (T)
1 tesla =
10,000 (or 104) gauss (G)
__ = US Congress and WHO Recommended limit
for constant human exposure = __
200 nanotesla, 2mG
an operation that transforms one function of a real variable into another. is a mathematical procedure to separate out the frequency components of a signal from its amplitudes as a function of time
Fourier transform
calculates the time domain from the frequency domain.
Inverse fourier transform (IFT)
First to recognize the existence of the __ , an uncharged and massless particle that carries off energy in radioactivity.
Wolf gang ernst pauli, neutrino
states that no two identical fermions may occupy the same quantum state simultaneously.
Pauli exlcusion principle
In particle physics, __ are particles which obey Fermi-Dirac statistics; they are named after __.
fermions, Enrico Fermi
1900 -1988 a Dutch-American theoretical physicist. In 1925, introduced the concept of a spinning electron, with resultant angular momentum and a magnetic dipole moment arising from the spinning electrical charge.
George eugene uhlenbeck
1937 Columbia University Professor __ working in the Pupin Physic Laboratory in New York City, observed the quantum phenomenon dubbed nuclear magnetic resonance (NMR). He recognized that the atomic nuclei show their presence by absorbing or emitting radio waves when exposed to a sufficiently strong magnetic field. Published “A New Method of Measuring Nuclear Magnetic Moment” in 1938, where the first MR signal from LiCl was reported. Awarded the Nobel Prize for Physics in 1944.
Isidor I.Rabi
Dutch Physicist In September 1937, he and his co-worker Broer, reported unsuccessful attempts to observe nuclear magnetic resonance in pure crystalline materials. First to demonstrate the phenomenon of paramagnetic relaxation.
Cornelius Jacobus Gorter
1907 – 1976 a Soviet physicist. discovered electron paramagnetic resonance in 1944.
Yevgeny Konstantinovich Zavoisky
1946 discover magnetic resonance phenomenon. Nobel Prize for Physics was shared by __ and __. __ (Stanford University) and
__ (Harvard University) developed instruments, which could measure the magnetic resonance in bulk material such as liquids and solids.
Felix Bloch and Edward Purcell
The year often regarded to as the birth of MR
1952
creates a one-dimensional MR image.
Herman Carr
Same book puts the year commonly regarded as the year in which MR was discovered as __.
1946
1956 The “Tesla Unit” was proclaimed in the Rathaus of Munich, Germany by the __ . All MRI machines are calibrated in “Tesla Units”. The strength of a magnetic field is measured in Tesla or Gauss Units. The stronger the magnetic field, the stronger the amount of radio signals which can be. elicited from the body’s atoms and therefore the higher the quality of MRI
International Electro-technical Commission-Committee of Action
First to demonstrate clinical MR images of a human finger using his technique. Showed how signals can be mathematically analyzed which later gave way to EPI technique in 1977. EPI (echo-planar imaging) was the first ultra high-speed imaging technique.
Peter mansfield
were awarded with the 2003 Nobel Prize in Physiology and Medicine.
Paul lauterbur and petermansfield
Give at least 3 of Peter mansfield contribution
NMR diffraction in solids, Slice selection, Active magnetic shielding of gradient coils, Echo volume imaging, Active acoustic shielding methods that lower noise levels produced by gradient coils
was Professor of Medical Physics at the University of Aberdeen from 1965 until his retirement in 1992. He is known for his and his colleague’s work in the development of radionuclide imaging, magnetic resonance imaging (MRI) and, in particular, positron emission tomography (PET).
John mallard
The whole body magnet was first built by __ In cooperation with the __; started in 1972 under the direction of __ and led by __. Originated the “spin-warp” method of spatial localization for MRI, T1 values for normal and malignant animal and human tissue were presented
Oxford Instruments Ltd, University of Aberdeen, John Mallard, James Hutchison
a physician and experimenter working at Brooklyn’s Downstate Medical Center discovered that hydrogen signal in cancerous tissue is different from that of healthy tissue because tumors contain more water. More water means more hydrogen atoms. When the NMR machine was switched off, the bath of radio waves from cancerous tissue will linger longer then those from the healthy tissue.
Raymond damadian, 1971
applies for a patent which describes the concept of NMR being used for above purpose. He illustrates major parts of MRI machine in his patent application
Raymond damadian, 1972
a chemist and an NMR pioneer at the State University of New York, Stony Brook, produced the first NMR image. It was of a test tube.
Paul lauterbur, 1973
referred to the joining together of a weak gradient magnetic field with the stronger main magnetic field, allowing the spatial localization of 2 tubes of water. Introduced the use of gradients in the. magnetic field.
Zeumatography
Raymond damadian receives his patent
1974
Richard Ernst proposes using phase and frequency encoding and Fourier transform for acquisition of MR images. Instead of Paul Lauterbur’s back- projection, he timely switched magnetic field gradients . This basic reconstruction method is the basis of current MRI techniques.
1975
First images could be presented. A cross section through a finger by Peter Mansfield and Andrew A. Maudsley. Peter Mansfield also could present the first image through the abdomen.
1977/78
Raymond Damadian demonstrated MRI of the whole body.
1977
In this same year, Peter Mansfield developed the echo-planar imaging (EPI) technique. This technique will be developed in later years to produce images at video rates (30 ms / image)
1977
nearly five hours after the start of the first MRI test, the first human scan was made as the first MRI prototype.
July 3,1977
demonstrated imaging of the body using Ernst’s technique in __. A single image could
be acquired in approximately five minutes by this technique
Edelstein and coworkers, 1980
Schering submitted a patent application for Gd-DTPA dimeglumine.
1981
The first ‘magnetization-transfer’ imaging by?
1982, robert N. Muller
Toshiba obtained approval from the Ministry of Health and Welfare in Japan for the first commercial MRI system.
1983
FONAR Corporation receives FDA approval for its first MRI scanner.
1984
the imaging time was reduced to about five seconds, without sacrificing too much image quality. The same year people were developing the NMR microscope, which allowed approximately 10 mm resolution on approximately one cm samples.
1986
introduced RARE (rapid acquisition with
relaxation enhancement) imaging.
1986: Jürgen Hennig, A. Nauerth, and Hartmut Friedburg (University of Freiburg)
Axel Haase, Jens Frahm, Dieter Matthaei, Wolfgang Haenicke, and Dietmar K. Merboldt (Max-Planck-Institute, Göttingen) developed the __ (__) sequence
FLASH (fast low angle shot)
Le Bihan publishes an article in Radiology, which describes diffusion weighted imaging (DWI).
1986
Real time MR imaging of the heart is developed
1987
echo-planar imaging was used to perform real-time movie imaging of a single cardiac cycle. In this same year __ was perfecting magnetic resonance angiography (MRA), which allowed imaging of flowing blood without the use of contrast agents.
1987, Charles Dumoulin
Schering’s MAGNEVIST gets its first approval by the FDA
1988
Richard Ernst was rewarded for his achievements in pulsed Fourier Transform NMR and MRI with the Nobel Prize in Chemistry.
1991
describe imaging of axonal transport of supermagnetic metal oxide particles, a technique, which later becomes important in imaging of neural tracts.
1991, filler and colleagues
In __ , __ was developed independently by the University of Minnesota’s Center for Magnetic Resonance Research (CMRR) and
Massachusetts General Hospital’s (MGH)
MR Center.
1991, fMRI
was developed. This technique allows the mapping of the function of the various regions of the human brain. Six years earlier many clinicians thought echo- planar imaging’s primary applications was to be in real-time cardiac imaging. The development of fMRI opened up a new application for EPI in mapping the regions of the brain responsible for thought and motor control.
1993, functional mri
The first intraoperative MR unit developed by GE and Harvard is installed in the Brigham and Women’s Hospital in Boston.
1994
From __ to __ Fonar was paid for the infringement of it’s patents from ‘nearly every one of its competitors in the MRI industry including giant multi-nationals as Toshiba, Siemens, Shimadzu, Philips and GE’.
1992, 1997
In addition to research centers and large hospitals, small remote hospitals and imaging centers begin to utilize MRI predominantly for neuroimaging and musculoskeletal imaging
1990s
developed the first truly portable MRI technology and made MRI technology available in the office of the clinician
1999, magneVu
Cardiac MRI, Body MRI, fetal imaging, functional MR imaging are further developed and become routine in many imaging centers. Research centers make significant strides forward in imaging cartilage on high field scanners. The number of free standing MRI centers, most of which utilize low or moderate field MR scanners significantly increases.
2000s
