The technique has previously been used to look at tumors in breast tissue and cartilage in human knee and ankle joints, but this study tests its ability to visualize a class of miniscule plaques that are a hallmark feature of Alzheimer's disease.
Scientists have long known that Alzheimer's disease is associated with plaques, areas of dense built-up proteins, in the affected brain. Many also believe that these plaques, called amyloid beta (Aß) plaques after the protein they contain, actually cause the disease. A major goal is to develop a drug that removes the plaques from the brain. However, before drug therapies can be tested, researchers need a non-invasive, safe, and cost-effective way to track the plaques' number and size.
That is no easy task: Aß plaques are extremely small – on the micrometer scale, or one millionth of a metre. And conventional techniques such as computed tomography (CT) poorly distinguish between the plaques and other soft tissue such as cartilage or blood vessels.
A technique developed at Brookhaven, called diffraction-enhanced imaging (DEI), might provide the extra imaging power researchers crave. DEI, which makes use of extremely bright beams of x-rays available at synchrotron sources, is used to visualize not only bone, but also soft tissue in a way that is not possible using standard x-rays. In contrast to conventional sources, synchrotron x-ray beams are thousands of times more intense and extremely concentrated into a narrow beam. The result is typically a lower x-ray dose with a higher image quality.
In this study, researchers successfully used DEI in a high-resolution mode called micro-computed tomography to visualize individual plaques in a mouse-brain model of Alzheimer's disease.
MEDICA.de; Source: Brookhaven National Laboratory