An American and a Briton won the Nobel Prize in medicine (search) Monday for discoveries that led to MRI, the body-scanning technique that has revolutionized the detection of disease by painlessly revealing internal organs in exquisite 3-D detail.
Paul C. Lauterbur (search), 74, of the University of Illinois at Urbana-Champaign and Sir Peter Mansfield (search), 69, of the University of Nottingham in England were honored for work they did independently of each other in the 1970s.
Magnetic resonance imaging, or MRI, represents "a breakthrough in medical diagnostics and research," with more than 60 million procedures done each year around the world, the Nobel Assembly in Stockholm, Sweden, said.
The now-routine technique became available to doctors in the 1980s. It excels at creating images of so-called soft tissue, allowing many patients to avoid exploratory surgery. For example, doctors can see a tumor in the abdomen or get detailed images of cartilage and ligaments within the knee without operating.
MRI can also reveal whether lower back pain stems from pressure on a nerve or the spinal cord. It can show chemical changes in tissue that indicate disease. And it can lay out road maps for surgeons before they operate for cancer or other diseases.
Lauterbur said he was "surprised and very gratified" by the award. "In particular, I believe, I think the work has been helpful to many people, and I'm happy that has been acknowledged by the Swedish academy," he said.
Mansfield said: "We've waited a long time, but I must say, I didn't really expect anything like this to come at this point in my life.... My 70th birthday is this week and although I'm retired, I'm still working in research, but I'd given up all hopes and ideas of receiving anything in the way of an accolade of this type."
The Nobel in medicine comes with a check equivalent to $1.3 million.
Dr. Walter Kucharczyk, president-elect of the International Society of Magnetic Resonance in Medicine and chairman of medical imaging at the University of Toronto, said MRI is "now an indispensable part of my daily work for diagnosing disorders of the brain and spine, and similarly for neural surgeons and neurologists worldwide."
Kucharczyk said the prize for Lauterbur and Mansfield is "appropriate recognition of two tremendous scientists."
Unlike X-ray devices, which rely on radiation, MRI machines use powerful magnetic fields and radio waves to create remarkably detailed images of internal tissues. They essentially provoke hydrogen atoms -- part of the water molecules found densely throughout the body -- to emit signals that can be analyzed and assembled into images.
MRI gave doctors a way to get detailed images of soft tissues like the brain and other internal organs, which can be seen only poorly with X-rays. One expert compared the difference to shining a bright light on the tissues rather than just seeing dim shadows. A variation called functional MRI can also track how active various parts of the brain are during different tasks.
While working at State University of New York at Stony Brook, Lauterbur discovered the possibility of creating a two-dimensional picture by introducing variations in magnetic fields.
Mansfield further developed the use of such gradations in magnetic fields and showed how the signals from the atoms could be mathematically analyzed. That made it possible to develop a useful imaging technique.
He also showed how very fast imaging could be done, which became technically possible in medicine a decade later.
South African writer J.M. Coetzee won the Nobel for literature on Thursday. The physics award will be announced Tuesday and the chemistry and economics awards Wednesday. The Peace Prize will be awarded Friday.
The awards are presented to the recipients on Dec. 10, the anniversary of industrial Alfred Nobel's death in 1896.