Computer-aided tomography (CAT) scans are used widely in hospitals to produce detailed X-ray images of organ tissue. Now, researchers at Sandia National Laboratories in Livermore, Calif., have developed a technology that can produce images 1,000 times more detailed than CAT scans. Called ion microtomography (IMT), the technique could eventually be used to study individual cancer cells and identify the plaques in the brain that signal Alzheimer's disease.
In IMT, narrow beams of ions--charged particles--produced by a linear accelerator are shot through a sample. A silicon detector measures how much energy was lost passing through the sample, and a computer analyzes those data to determine the sample's structure from various angles. IMT is far less destructive to living tissue than X-rays, so it holds particular promise for biomedical imaging. It also has uses in industry: for inspecting extremely small manufactured parts and materials used in microelectronics and fusion research.
The technology does have one drawback: It can take hours to produce images because of the extensive computer analysis. Researchers are working on speeding up the process. They're also developing a new IMT system that will produce images that are 100 times more detailed. That should allow them to view structures within single cells.