New test delivers biopsy results in minutes

Posted by Emma Woollacott

Patients may no longer have to wait days for biopsy results, thanks to a new tissue-imaging technique that gives results in a matter of minutes.

The University of Illinois research team demonstrated the novel microscopy technique - called nonlinear interferometric vibrational imaging (NIVI) - on rat breast-cancer cells and tissues.

The technique produced easy-to-read, color-coded images of tissue, outlining clear tumor boundaries, with more than 99 percent confidence in less than five minutes.

It also gave more objective results than current methods, which are based on visual interpretations of cell shape and structure, says professor Stephen Boppart.

"The diagnosis is made based on very subjective interpretation – how the cells are laid out, the structure, the morphology," he says. "This is what we call the gold standard for diagnosis. We want to make the process of medical diagnostics more quantitative and more rapid."

NIVI analyzes molecular composition. Normal cells have high concentrations of lipids, but cancerous cells produce more protein. By identifying cells with abnormally high protein concentrations, the researchers could differentiate between tumors and healthy tissue without waiting for the stain to set in.

Another advantage of the NIVI technique is more exact mapping of tumor boundaries - 'a murky area for many pathologists', says the team. "Sometimes it’s very hard to tell visually whether a cell is normal or abnormal," says Boppart. "But molecularly, there are fairly clear signatures."

The researchers are working to improve and broaden the application of  their technique, making it faster, for real-time imaging, and exploring new laser sources to make NIVI more compact or even portable.

They also are developing new light delivery systems, such as catheters, probes or needles that can test tissue without removing samples.