MRI-Like Technique Spots Alzheimer's Plaques for the First Time
Nov. 22, 1999 (Atlanta) -- Researchers may have moved a step closer to
understanding one of the central mysteries of Alzheimer's disease -- and that
is the role of plaques, those small clots of tissue debris found in the brains
of those who suffer from the disease.
For the first time, a team of researchers has found a way to see the plaques
using an X-ray-like technique known as magnetic resonance microscopy (MRM).
Previously, plaques were only viewable after Alzheimer's patients had died, by
taking small pieces of brain tissue and viewing them under a microscope.
The research, conducted at Duke University and published in today's edition
of the Proceedings of the National Academy of Sciences, is but a small
step towards eventual use of the technique on live humans. So far, the
technique has only been tested on brain samples of Alzheimer's patients who
have died, and the next step is to perfect its use on mice. But even that is
still a year or two away.
"Mice can fit into the very high field magnet [used in the Duke
study]," says Michael Weiner, MD, director of the magnetic resonance unit
at the San Francisco VA Hospital, "so the techniques are not so difficult
to translate to a mouse brain." But Weiner says translation to human
subjects won't be so easy.
Still, the apparently long road of this research could answer one of the
most baffling questions about Alzheimer's disease: what role do plaques play?
They are considered the 'hallmark' of the brain-wasting disorder, but no one is
sure why. Do they cause the disease? Or are they result of it? The researchers
hope that by being able to "see" the disease progressing, they can
answer that question, or, at the very least, can use the technique to guide the
development of new Alzheimer's drugs.
"It's possible that this could lead to an important technological
breakthrough," Weiner says. But he cautions "it's not an easy leap"
to apply it to the many people with Alzheimer's disease.
- Plaques are small clots of tissue debris found in the brains of Alzheimer's
patients that, until now, could only be seen during an autopsy.
- A new technique using magnetic resonance microscopy (MRM), an X-ray-like
technique, may allow physicians to view the plaques.
- Although the application in humans is still far off, researchers hope the
new tool will help advance the understanding of Alzheimer's, possibly answering
the question of whether the plaques are the cause, or just symptoms, of the