The History of Magnetic Resonance Imaging (page 2)

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test_tubes.gif (11800 bytes) One would not think that from reading the title that it represented the foundation for a revolution in imaging. Indeed the paper was nearly not published having been initially rejected by the editor as not of sufficiently wide significance for inclusion in Nature. In this seminal paper Lauterbur described a new imaging technique which he termed zeugmatography (from the Greek zeugmo meaning yoke or a joining together). This referred to the joining together of a weak gradient magnetic field with the stronger main magnetic field allowing the spatial localisation of two test tubes of water.

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Further applications of MRI are currently being assessed. The manipulation of gradients and enhanced software give not just exquisite anatomical detail but also provide functional information as in perfusion and diffusion studies of the brain in vivo.
Two- and three-dimensional MR angiography provide a roadmap of vessels in any part of the body, together with the ability to obtain functional velocity profiling of blood flow. This non-invasive technique is likely to replace conventional diagnostic x-ray angiography in the near future.

He used a back projection method to produce an image of the two test tubes. This imaging experiment moved from the single dimension of NMR spectroscopy to the second dimension of spatial orientation being the foundation of MRI.
MR also owes a debt to computed tomography (CT) as it was developed initially on the back of CT but quickly outpaced that technique. The impact that CT had in the medical community is not to be disregarded as it stimulated interest both of clinicians and manufacturers to the potential impact that this new technique. It had already demonstrated the advantage of tomographic sections through the head or body of a patient allowing diagnosis of disease processes in a non-invasive way.
In the late 70's and early 80's a number of groups, including manufacturers, in the US and UK showed promising results of MRI in vivo. This was, and still is, a technological challenge to produce wide bore magnets of sufficient uniformity to image the human body. In the UK these included the group from the Hammersmith (Professor R Steiner & Dr (now Professor) G Bydder) collaborating with Picker Ltd. (a subsidiary of GEC) at Wembley (Dr Ian Young), two independent groups in Nottingham (Professor P Mansfield and Dr W Moore), and in Aberdeen (Professor J Mallard & Dr J Hutchinson). The first commercial MR scanner in Europe (from Picker Ltd.) was installed in 1983 the Department of Diagnostic Radiology at the University of Manchester Medical School (Professor I Isherwood & Professor B Pullen).

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3D Maximum Intensity rendering of Time-of-flight cerebral angiogram, 1.5T system 1997 and subtraction angiogram of pulmonary vessels, 1.5T system 1998.

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The use of real-time MRI (MR fluoroscopy) and more open magnet systems allow in vivo interventional studies to be performed. The future for MRI is very bright indeed!