The duel over who should get credit for the original MRI
BY CAMERON STRACHER
Friday, June 14, 2002 12:01 a.m. EDT
If you've been relaxing next to your radio recently, basking in your good health, you may have heard a series of ads from a company called Fonar touting its "stand up" MRI, with the tag line: "The company that invented the original MRI has reinvented it."
Sounds innocent enough. But the invention claim is the subject of a ferocious battle in the scientific community over who gets credit for magnetic resonance imaging, the process that "sees" into the body to catch oddities and errors--tumors especially--that might otherwise go undiagnosed.
"MRI is the perfect candidate for the Nobel," says Hayes Griffiths, a professor of chemistry at the University of Oregon. "It's something that has improved and advanced medicine in a way no one can argue with." But it's not clear if the Nobel committee will ever note the achievement. It may have too much trouble choosing between inventor-rivals. "What bothers me," says Nicholas Bloembergen, the 1981 Nobel laureate in physics, "is that the institute in Stockholm has not yet awarded the prize for this great discovery. I believe this is partly due to controversy over Damadian's role."
That would be Raymond Damadian, a medical doctor and the founder of Fonar. There is little doubt that he has some claim to the "inventor" label in his company's ad. Indeed, the National Academy of Sciences, having commissioned an article for its "Beyond Discovery" series on the MRI, got a draft that called Dr. Damadian "crucial" to its invention and attributed four of 12 MRI "milestones" to him.
That was 1997. When the paper finally appeared last summer, the milestones went by without Dr. Damadian anywhere in sight. The text played down his role, saying the method he discovered had "not proved clinically reliable in detecting or diagnosing cancer." It went on to award the palm to the chemist Paul Lauterbur, and not without reason. He, too, has a claim to the MRI's invention.
So what is going on here? Nothing short of a scandal, according to Dr. Damadian, whose lawyers have fired off a threatening letter to the NAS. (The article was recently revised on the academy's Web site, but Dr. Damadian says it is still not fair.) If nothing else, the whole episode shows how hard it can be to point to the exact moment when a miraculous device came into existence, or to single out a Great Man for credit, when, in fact, a series of geniuses often push science and technology to their payoff point. And given the nature of the human psyche, it is sometimes hard to share credit where credit is due.
In a 1971 paper in Science, Dr. Damadian described, for the first, time, the different-from-normal "relaxation rates" of cancerous tissue. What are these?
Atomic nuclei function like tiny planets, complete with spin and magnetic properties. In the 1930s, the physicist Isidor Rabi subjected such nuclei to an external magnetic field and noticed that they align themselves either parallel to it or "anti-parallel." By bathing the nuclei with radio waves, he was able to "flip" their orientation. For his work, he won the Nobel Prize.
Two other scientists, Edward Purcell and Felix Bloch, showed that relaxation time--the time it took nuclei to return to their original state--could be measured in two forms, dubbed T1 and T2. For their discovery of what would be called "nuclear magnetic resonance," or NMR, they won the Nobel Prize, too. NMR was later re-christened "magnetic resonance imaging," or MRI, to avoid the troubling word "nuclear."
Although some scientists had tinkered with trying to obtain a signal from biological samples, it was Dr. Damadian who first conceived of using T1 and T2 measurements to scan the body for cancerous tissue. He patented his discovery and, in 1992, won a patent infringement lawsuit against General Electric for $110.5 million. Today, more than 95% of all MRI scans use T1 or T2 measurements.
But Dr. Damadian's initial work had several flaws. His scanning method relied on a point-by-point analysis of the entire human body, which proved impractical. And it turned out that relaxation rates are not a reliable indicator of cancer, as his paper had theorized.
Nevertheless, his observation of T1 and T2 differences in cancerous tissue was a Eureka moment for Paul Lauterbur. After seeing Dr. Damadian's experiment repeated by a graduate student, Mr. Lauterbur dined at a hamburger joint, where he had a flash of brilliance.
He realized he could subject the nuclei to a second magnetic field that varied in strength in a precise way. Though the idea of a "magnetic field gradient" was not new, Mr. Lauterbur was the first to see how it could be used to reconstruct an image. He wrote his idea in a notebook and had it witnessed the next day. His work, with later contributions from Peter Mansfield, forms the basis for modern MRI imaging.
Over the years, Mr. Lauterbur has been less than forthcoming about giving Dr. Damadian credit. In his notebook he acknowledged Dr. Damadian's 1971 paper, but his subsequent articles didn't mention it. Mr. Lauterbur explains that by the time he published his first paper "another group had made a measurement on a tumor in a mouse's tail. I needed to keep the list of references to very few, so I used that one."
Even today, when Mr. Lauterbur discusses his Eureka moment, he says that he happened to be present when a student "was doing some studies of tumors." He doesn't mention that the student was repeating Dr. Damadian's experiment. For his part, Dr. Damadian says credit for inventing the MRI goes to "me, and then Lauterbur," though he thinks both of them should get the Nobel Prize. Mr. Lauterbur claims sole credit.
All this helps explain the long delay of that article from the National Academy of Sciences. It took four years from draft to finished product, longer than any other article in its series (devoted to explaining basic scientific research to the public). And it was revised at least twice before the latest revision because of "the Damadian problem," as someone close to the publishing process confessed.
There is another dimension to this debate, too. For research scientists, Mr. Lauterbur is one of their own. Dr. Damadian is the outsider, the M.D., who dared to profit from his discovery. He is often characterized as brash and litigious. In any case, he is not shy: "If I had not been born, would MRI have existed? I don't think so. If Lauterbur had not been born? I would have gotten there. Eventually."
Who can say? "The most important thing you can do as a scientist is to get credit for your ideas," notes Charles Slichter, a professor of chemistry at the University of Illinois. "You don't want to be forgotten." Maybe this year Stockholm can decide whom to remember.