Providing excellent soft tissue contrast and a huge variety of accessible tissue parameters, MRI has revolutionized the diagnosis and treatment of a wide variety of medical conditions.1,2

MRI allows for the noninvasive visualization of structural and functional information of the human body.2 New magnetic resonance techniques, pulse sequence acquisition methods, and innovative hardware are continually being developed to improve image quality and shorten scanning times.2 The furious pace of innovation in MRI owes a huge debt to the brilliance and hard work of the scientists who pioneered it, a tiny few of whom are acknowledged below.

Discoveries in nuclear magnetic resonance

The phenomenon of nuclear magnetic resonance (NMR) was first described by Isidor Isaac Rabi at Columbia University in 1938, along with a technique for measuring the magnetic characteristics of atomic nuclei.2,3 Working independently, Felix Bloch and Edward Purcell first observed the NMR phenomenon in liquids and in solids.2,3 In 1951, Erwin Hahn developed a spin echo method to study molecular diffusion in liquids, which proved important for measuring relaxation times.2,4 In 1955, Erik Odeblad and Gunnar Lindström from Stockholm published their research in relaxation time measurements of living cells and excised animal tissue, showing that different tissues had different relaxation times, probably due to different water content and bindings to lipids. This laid the foundations for NMR and MRI in biomedicine.3

A decade later, Richard Ernst developed Fourier transform NMR spectroscopy in 1966.2 But it was not until 1971 that Raymond Damadian at Downstate Medical Center in Brooklyn used NMR in biomedical applications.3 Raymond Damadian measured T1 and T2 relaxation times in rat tumors. He found that tumor tissue had longer T2 times than normal tissues, which resulted in him commenting, somewhat prophetically, that the technique might “prove useful in the detection of malignant tumors.”2 Meanwhile, independently in 1973, Paul Lauterbur, a professor of chemistry at the State University of New York at Stony Brook, and Peter Mansfield, a physicist at the University of Nottingham in the UK, described using magnetic field gradients to localize NMR signals. This technical development laid the groundwork for modern MRI.2,3 A number of research groups, mostly in Britain, constructed early scanner prototypes based on resistive magnets, but early image quality was poor and, by modern standards, the scanning speed was excruciatingly slow.1

Use of MRI in medical imaging

By 1977, a number of researchers were exploring using MRI in humans.2 In that year, Raymond Damadian managed to generate crude images of the human thorax2 and Peter Mansfield and Andrew Maudsley published a cross-sectional scan of a human finger.5

There is some controversy as to who produced the first commercial whole-body MRI scanner, as both Oxford Instruments, a spin-off company from Oxford University, and FONAR, founded by Raymond Damadian, introduced scanners in 1980.2 Although his original research was found to be flawed, having no control group, Raymond Damadian’s publicity stunts and colorful self-promotion helped to generate interest in the field of NMR.3 Seeing the potential, General Electric and Siemens entered the arena and by 1983 had both produced their own commercial scanners.2 With the emergence of new hardware, Jürgen Hennig, Arno Nauerth, and Hartmut Friedburg from the University of Freiburg pioneered rapid acquisition with relaxation enhancement (RARE) imaging in 1986, which is also known under the names of fast spin echo (FSE) or turbo spin echo (TSE).3,4

Emergence of functional MRI

Groundbreaking work in diffusion imaging by Michael Moseley at Stanford University in 1984 provided the fundamentals for functional MRI (fMRI) techniques, which measure brain activity by detecting changes associated with blood flow.2,3 In 1986, Denis Le Bihan developed a method for calculating diffusion coefficients using Moseley’s method, which gave birth to diffusion tensor imaging and fMRI using blood oxygenation level-dependent (BOLD) techniques.2 Another emergent technique was contrast-enhanced MR angiography (MRA), which uses ultrafast MRI imaging methods to achieve flow-independent vascular imaging following the injection of a gadolinium-based contrast agent (GBCA).2 Contrast-enhanced MRA is currently in common use for assessing arterial and venous systems in many anatomic areas.2

Advent of gadolinium-based contrast agents

Gadolinium chelates are currently the most widely used agents to enhance contrast in MRI.2 The gadolinium (Gd3+) ion shortens the T1 and T2 times of hydrogen protons.2

Commercial manufacturers first started to produce GBCAs which chelated the Gd3+ with a linear ligand in the late 1980s based on clinical evaluations of the product in patients with brain tumors,2,6 as well as GBCAs that chelated the Gd3+ with a macrocyclic ligand.2,3,6

Collaboration-driven innovation

The development of MR technology was somewhat unusual in that it was driven by a strong interplay between basic research in physics, radiology, and hardware development.1 Although at its most basic level the system architecture has remained conceptually largely unchanged, individual system components have evolved enormously over the past decades.1 Advances in hardware and techniques, coupled with evolving clinical needs have spurred the development of this technology. The major research areas included achieving generally higher magnetic fields to boost polarization and thus improve the signal-to-noise ratio. Acquisition speeds were increased, enhancing scanning efficiency. Overall system performance was enhanced with hardware and software improvements. Finally, image contrast was enhanced through the development and optimization of future contrast-enhancing agents.1,7

Some Nobel Prizes for research in NMR

  • Isador Isaac Rabi was awarded the Nobel Prize in Physics in 1944 for developing molecular beam magnetic resonance, which was used for studying the magnetic properties and internal structure of molecules, atoms, and nuclei4
  • Felix Bloch and Edward Purcell were awarded the Nobel Prize in Physics in 1952 for the application of nuclear magnetic resonance to study chemical compounds4
  • Richard Ernst won the Nobel Prize in Chemistry in 1991 for the development of high-resolution NMR spectroscopy4
  • Paul Lauterbur and Peter Mansfield were awarded the Nobel Prize in Medicine or Physiology in 2003 for the invention of MRI4

Although MRI may be approaching maturity, it will continue to undergo constant innovation.1 The future of MRI is bright with the promise of new techniques, technologies, and advanced analytical software to provide better diagnostic information, increasing diagnostic confidence and offering a more patient-oriented service.1


  1. Börnert P, Norris DG. A half-century of innovation in technology-preparing MRI for the 21st century. Br J Radiol. 2020;93(1111):20200113.
  2. Ai T, Morelli JN, Hu X, et al. A historical overview of magnetic resonance imaging, focusing on technological innovations. Invest Radiol. 2012;47:725-741.
  3. Rinck PA. Magnetic Resonance in Medicine: A Critical Introduction. 13th ed. Norderstedt, Germany: European Magnetic Resonance Forum; 2021.
  4. Collins J. The history of MRI. Semin Roentgenol. 2008;43:259-260.
  5. Mansfield P, Maudsley AA. Medical imaging by NMR. Br J Radiol. 1977;50:188-194.
  6. U.S. Food and Drug Administration. FDA drug safety communication: FDA warns that gadolinium-based contrast agents (GBCAs) are retained in the body; requires new class warnings. https://www.fda.gov/drugs/drug-safety-and-availability/fda-drug-safety- communication-fda-warns-gadolinium-based-contrast-agents-gbcas-are-retained-body. Accessed March 30, 2022.
  7. de Haën C. Conception of the first magnetic resonance imaging contrast agents: a brief history. Top Magn Reson Imaging. 2001;12(4):221-230.