Vew MRI discussed

Monday, March 17, 2003 | 9:52 a.m.

A few years ago, when Dr. Ronald Walsworth began research on light beams and a cloud of atoms in a Harvard University laboratory, he had no idea it would lead to a cheaper, walk-in MRI.

Magnetic resonance imaging uses radio waves linked with computers to produce an image of body tissue, such as a heart, lungs, ligaments or a brain.

In a couple of weeks, the results of Walsworth's research will be tested with human patients to see if an MRI can spot a bleeding vein or artery deep in the lungs, he said during a recebt lecture last week at the University of Nevada, Las Vegas.

Walsworth is a physicist and a physician who lectures at Harvard, practices physics at Smithsonian Center for Astrophysics and is teaming up with physicians at Brigham Women's and Children's Hospital and Massachusetts General Hospital in Boston to try out his modified MRI.

The MRI that Walsworth and his research team built looks like a metal shower cabinet. The device uses lower frequency radio waves that do not require the thick shielding required on current machines and would cost far less than the average $3 million MRI.

When a patient lies down for a typical MRI, the lungs and heart shift and do not allow physicians to observe intricate problems, he said. The newer version allows a patient to walk in and sit upright for the procedure.

If the technology proves itself, Walsworth plans to develop a portable MRI that could capture internal images of premature infants bundled in their incubators without disturbing the frail babies.

During the lecture at UNLV, Walsworth recounted the story of "stopped light," an experiment at Harvard reported by the New York Times in January 2001.

The newspaper's headline described how scientists "stopped" a laser beam in a cloud of atoms, then released it and sent it on its way.

"Here I was on the front page of the New York Times," Walsworth said. He and a few colleagues were so sensitive to the publicity that they modified the headline to read "... and send hype on its way."

Sometimes, the media overplays a story, he said.

The ability to store light could help researchers working on super-secure communications to preserve vital bits of information and protect information transfers from hackers, he said.