MRI: The first clinical whole-body MRI scanner

John Mallard obtained his tertiary education at University College Nottingham. Mallard’s supervisor was Professor L F Bates who was an expert in magnetism. Mallard’s PhD thesis involved measuring the paramagnetic properties of uranium. There were iron impurities in the uranium that could be magnetically measured. At the end of his postgraduate studies, Mallard obtained a job at the Liverpool Radium Institute. He was introduced to some developmental work for thyroid uptake tests using radioactive thyroid I-131. They started learning how to image the thyroid by moving, what was at that time, a collimated Geiger counter, then eventually a collimated scintillation counter. The radiation detector moved over the neck to create an image of the thyroid’s shape, size and function. Benign and malignant tumours could be detected from the function and image results.

Mallard moved on to the Hammersmith Hospital. There, he used his newly learnt experience to design and build the first scanner – initially for thyroid studies but later brain scans. The patient moved through the scanner’s detector on a ’floating top’ couch.

Hammersmith Hospital installed the world’s first medical cyclotron and Mallard became involved with using short half-life radioisotopes for organ imaging. Information on brain tumours obtained from these scans were particularly advantageous for neurosurgeons when the patient went for their operation. This kind of service was believed to have been the first of its kind in the world.

Mallard, was appointed Professor of Biomedical Physics at Aberdeen University in 1965. By 1967, he had organised the installation of their first commercial gamma camera made by Nuclear Enterprises of Edinburgh. Then, in 1973, Mallard’s Department developed the Aberdeen Section Scanner which was able to produce single tomographic slices of the brain. The image was produced from a pair of scintillation counters which scanned and then rotated around the patient’s head. He also developed a gamma camera SPECT system in 1978 by mounting a Nuclear Enterprises gamma camera onto a rotating gantry. Successful completion of these nuclear medicine clinical projects assisted them in their development of the first clinically useful MRI whole body scanner for regular patient services.

Key members of Mallard’s R&D 1970 – 80 team were Dr Jim Hutchison, Dr Bill Edelstein (Research Fellow), Dr Margaret Foster (Biology expert), Dr Francis Smith (Radiologist/Nuclear Medicine Physician), Thomas Redpath (Research Assistant) and Glyn Johnson (Research Assistant).

On the basis of Damadian’s 1971 reported results and their own laboratory data using ESR, Mallard decided to build his own Nuclear Magnetic Resonance Imager in 1973 – 74.

Dr Jim Hutchison (then an Aberdeen Research Assistant) built the imager (Hutchison et al, 1974; Hutchison, 1976) and Mallard’s research group published the world’s first known MRI of a mouse in 1974 (Mallard et al, 1980).

The MRI views of the mouse’s organs were sufficiently good to convince Mallard’s research team to start developing a whole-body CT scanner for humans.

It took Mallard’s team another six years (1979) to build and develop a suitable whole-body imager for patients. Even images produced by the end of 1979 were still badly spoiled by organ motion artefacts. Hutchison, Edelstein, Redpath and Johnson were all commissioned to work out why the method of plane slice Fourier calculation (first published by Mansfield, at Nottingham University) would not work.

In a recent ISMRM note dedicating the late Bill Edelstein who died in 2014,

the society reprinted an article by Hutchison, Redpath and Johnson. The article explained how Edelstein helped them solve the MRI motion problem. He came up with a better technique by developing a two-dimensional Fourier transformation (‘spin-warp’) method to produce the MR image (Edelstein et al, 1980, Hutchison, 1980, Johnson 1982).

It was not until early 1980 that the spin-warp calculation was written and tested. The significantly improved images confirmed the new method. It also implied that the new algorithm two-dimensional Fourier transformation made clinical MRI possible and that no other research centre could have succeeded to go clinical with whole-body MRI without spin – warp.

In summary, Mallard used expertise he obtained at Hammersmith designing and building early radioisotope CT scanners; he built and carried out ESR and MRI whole body mouse studies from 1974; and used that work as a precursor to eventually build and commission the first clinical MRI scanner in Aberdeen by 26 April 1980.

Lyn Oliver AM PhD 2021

Index:

1. Making the human body transparent
2. The pathway to clinical imaging
3. Creating an NMR image from biological samples
4. My brush with fame
5. 2003 Nobel Prize
6. The first clinical whole-body MRI scanner
7. Rekindling my ‘brush with fame’
8. IOMP Medal (2016) awarded to John Mallard for his MRI work

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Extract from:

Physics in Medicine, Making a Better Healthcare