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posted Jan 28, 2015, 9:37 PM by Ranmini Perera   [ updated Dec 2, 2015, 8:25 PM by Upali Salpadoru ]
Magnetic Resonance Imaging

Almost every major hospital in the world has a MRI scanner. These are ideal for the investigation of soft tissues in the body. They only produce a magnetic field and radio waves which are harmless compared to X-rays.
What is MRI ?

Fig. FONAR Multi position MRI scanners.

This is an important medical application derived from ‘Nuclear Magnetic Resonance’ (NMR), a technique used by chemists to determine the structure of molecules. The natural spinning of atomic nuclei magnetic forces. When an external magnetic field is Applied they get aligned. These can absorb energy from a radio wave of the same frequency. Once the field is removed they continue to  spin like tops gradually returning to their original form. The loosing of energy is effected by giving out radio waves.  The time it takes for this to occur is called ‘relaxation time’.

 

MRI has a history of over half a century. A number of Nobel awards have been made in this field during this time.

 

  • 1944 Isidor Rabi (Austrian/US) won the award for showing that the nuclei of atoms are magnetic.
  • I952  Felix Bloch (Swiss/US) and Edward Purcell (US) shared the Prize for showing that chemical information could be obtained by NMR.
  • 1991 Richard Ernst (Swiss) Born in 1933-      developed the NMR analytic method.
  • 2002 Kurt Wuthridge (Swiss) Born 1938-  developed 2D NMR spectroscopy.  to the Structure Analyses of Biological Macromolecules in Water Solution, anenvironment Similar to That in the Living Cell
Fig. Laureate Kurt Wudgeridge at the Mercury Bay Game Fishing Club in Whitianga, New Zealand, 1987.


It was Dr Raymond Damadian (US) who focussed NMR on biological tissues. In 1969 he observed that using this technology it would be possible to identify cancer cells inside the body. According to him there was a difference in relaxation time of cancer cells. He actually proposed a machine to scan the entire body, which was really ahead of his time

 Paul Christian Lauterbur 1929- 2007, (US) was having a meal with another scientist, Don Vickers.  Vickers narrated how he showed a signal from an NMR unit.  “What I have seen these before?”  Damadian quipped. When Vickers explained that it had originated from his finger inserted into an NMR probe. “ Oh my God !” exclaimed Damadian. “ We can build machines to put people in”.  Just as Damadian got pumped up from what he had seen ,  Lauterbur  got excited from what he heard. 1969.


Although Lauterbur and Vickers laughed at the idea as it would not have been possible to make such large magnets to people in the race for the development and rivalry commenced.


Lauterbur spent a sleepless night trying to devise an image from the radio waves .  Returning to Stony brook  he started experimenting with the NMR machines in the chemistry department usually working till midnight.  With the assistance of a mathematician he finally solved the problem.

 While he was involved in this work he continuously harboured two distant views.  The first was to  get full credit for the development  while the other was to get the legal rights as he expected it to be a million dollar venture. He did not want any collaboration with Damadian . “Damadian and I neither like nor trust one another” he had written to his patent lawyer.


In 1969 Damadian requested a grant of $89,000 to purchase NMR unit and as a referee he gave the name of Lauterbur.  Every appeal was rejected from there onwards.
Lauterbur submitted a paper to the journal Nature with NMR images, which was a landmark in the history of medical scanning.  This was flatly rejected with a remark that it would not have any useful applications. A revised version of this was published in 1973. Lauterbur  purposely avoided  giving any credit for the Damadian’s idea. He knew it would be advantages to introduce it as his original idea. Damadian developed a life long enmity towards him.
Although Lauterbur pleaded with the State University of New York (SUNY) authorities  to get a patent for his discovery they were not interested.  In the meantime EMI corporation of Britain produced the whole body CT scanner

which was using harmful X’ rays.In spite of this fact by 1077 over one thousand CT scanners were in use  all over the world.

Fig. Damadians plan for a body scanner.

In 1974  Damadian obtained a patent for the human NMR scanner. “Apparatus and method to detect Cancer in Tissues using relaxation times” but he did not have a method to obtain images. Later he published a paper explaining the differences in the NMR signals on various  tumours .
When his grant of  $225,000 from the National Cancer Institute  ended , all his appeals to get further assistance were denied. 


Peter Mansfield, who had been sent out of school at 15 for not having an aptitude for learning, who later qualified by attending night school, produced a paper in the British Journal of Radiology showing mages through a human finger. This immediately catalysed the MRI research towards building a whole body scanner.
Damadian published an image of an implanted tumour in a mouse. A few months later Lauterbur showed the stages in the growth of a tumour . As competition escalated Damadian said, “ I would have died before I let him beat me”
Dr. Damadian’s method was to examine the body point by point, whereas Lauterbur and Mansfield wanted to examine in layers. Dr.Damadian along with his loyal assistants Dr. Lawrence Minkoff and Dr.Michael Goldsmith decided to assemble the machine by themselves. They planned for a giant magnet with a cavity big enough to insert a human body.  Most of the NMR experts at the time  were quite sceptical about their project. A journalist described it as , “No one else had the imagination   … to jump to a whole body machine”.

Sixteen hours a day, six days a week they laboured for 1 ½  years. The machine looked like a tunnel and had a height of 10 feet weighing 1 ½ tons.  It was named as  “Indomitable”.  Once completed it had several drawbacks, magnet supplied only 10 % of the power expected. Damadian was the first specimen . A cardiologist was examining his heartbeat etc,.. He was too big and the antenna failed to get any signals. It took a week to persuade his slender assistant  Minkoff to volunteer. He paused for over 4 hours for a scan of the chest. The first human MRI scan performed on  2/7/1977. Damadian has won the race.

Fig. Dr.Damadian,Dr.Mincoff and Dr.Goldsmith after completing their gigantic task.


Lauterbur had a problem with the magnet he purchased. Mansfield uttered , “If  the magnet I ordered arrived sooner I would have got the first scan”. But he appreciated the effort. “ Anyone who builds a superconducting magnet must be an n usual guy” Lauterbur criticised Damadian technique,  FONAR  (Field Focused Nuclear Magnetic Resonance)  as PHONY MAR.


Damadian instead of presenting his achievement to other scientists as is the custom, introduced the ‘indomitable’ to a group of journalists. The highly exaggerated reports and reviews, antagonized the echelons in the field. Some commented , “The whole procedure can be suspicious”.  Another described it as, “similar to sales talk coming from a snake oil salesman”.


In 1980 President Reagan awarded  the National Medal for Tecchnology to Damadian and Lauterbur.  At the function when Lauterbur gave his hand, Damadian looked the other way.
 


Damadian changed from research scientist to an entrepreneur . He founded the FONAR corporation  and started selling MRI scanners. It became a billion dollar market in US although he had only a small share. The competition was tuff. In 1997 he won a legal battle with the giant corporation General Electric who had to pay  $128 million to Damadian.
Karolinska Institute having delayed the awarding of a Nobel prize in Medicine /Physiology for NMR, MRI technology, probably due to the failing of health of one recipient, hastily picked up Prof. Paul Christian Lauterbur and Sir Peter Mansfield in 2003.

Fig. Prof. Paul Lauterbur                                                         Sir Peter Mansfield.

Dr. Damadian could not bear this.  Although he received many awards he had missed the Nobel crown. “ I opened the door , and the others had walked through, while I am holding the door knob” he has said.


For the entire history of Nobel awards, the decisions had never been challenged.  Just 4 days after the announcement full page advertisement exclaimed, “ THIS SHAMEFUL WRONG MUST BE RIGHTED”.  The science community openly canvassed for and against Damadin.

 Reference:-  Prize Fight - The race and the rivalry to be the first in Science.

                       By Morton A Meyers MD. ( First published 2012)

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