February 12, 2003

(The Los Angeles Daily News) -- UCLA researchers have mapped the progression of cell death in Alzheimer's disease using computer-generated time-lapse video, a technology that may help in the development of new drug therapies and serve as an evaluative tool in the treatment of patients.

The team of neuroscientists from UCLA and the University of Queensland in Australia took magnetic resonance imaging scans every three months of 12 patients diagnosed with Alzheimer's and compared them to 14 healthy elderly volunteers. Able to detect fine changes in the MRI scans, the imaging technique displayed the sequence of destruction over a two-year span.

"Though the pictures are depressing, there's tremendous hope for evaluating drugs now that you can see this elapsing over time in a brain image," said Paul Thompson, assistant professor of neurology at UCLA and lead investigator. "It's a powerful approach."

Researchers found that Alzheimer's first attacked brain areas controlling memory. Then the disease hit areas affecting self-control and inhibition, followed by emotion. Toward the end, Alzheimer's destroyed sensation. Like lava flowing around rocks, the disease left islands of brain tissue intact, including those controlling vision and breathing. After two years, the entire brain was engulfed, Thompson said.

Though the sequence has been observed in cognitive tests of memory and language, the imaging technique provides a precise delineation of events, said Dr. Jeffrey Cummings, director of the UCLA Alzheimer's Disease Center and president of the Los Angeles chapter of the Alzheimer's Association. Until now, the physical degeneration had only been examined in autopsy studies, he said.

"The autopsy shows us what the battlefield looks like, but then you have to reconstruct the battle," Cummings said. With the imaging technique, "you watch the event unfold. This is a more secure way of knowing how the brain is affected."

Cummings recommended some patients for the study but was not involved in the research.

Bill Thies, vice president for medical and scientific affairs for the national Alzheimer's Association in Chicago, said the UCLA study is part of a larger effort to track the biology of the disease using competing technologies. What's needed is a much longer-term study that tracks the progression before the onset and through the entire course of the disease, he said.

"I've not seen anyone use this particular technique, which is very interesting," Thies said. "And it will be interesting to see if other people pick this up as a worthwhile technique."

On average, Alzheimer's patients in the study lost 5.3 percent of brain tissue a year. But in the memory regions, brain cell death occurred at higher rates, up to 10 percent. The healthy volunteers lost only 0.9 percent of brain tissue a year.

Thompson plans to use the imaging technique to evaluate people considered at risk for Alzheimer's. By the time of diagnosis, patients in the study had already lost 10 percent of their gray matter, making early detection a priority, he said.

An estimated 4 million Americans suffer from the disease, according to the Alzheimer's Association. About 10 percent of those are over 65 years of age, rising to 50 percent for those age 85 and older. Though current drug therapies may slow Alzheimer's, scientists have not yet found a cure.