Imaging breast cancer with light
A team of researchers at the University of Twente in the Netherlands have developed a prototype of a new imaging tool that may one day help to detect breast cancer early, when it is most treatable.
If effective, the new device, called a photoacoustic mammoscope, would represent an entirely new way of imaging the breast and detecting cancer. Instead of X-rays, which are used in traditional mammography, the photoacoustic breast mammoscope uses a combination of infrared light and ultrasound to create a 3-D map of the breast.
In the new technique, infrared light is delivered in billionth-of-a-second pulses to tissue, where it is scattered and absorbed. The high absorption of blood increases the temperature of blood vessels slightly, and this causes them to undergo a slight but rapid expansion. While imperceptible to the patient, this expansion generates detectable ultrasound waves that are used to form a 3-D map of the breast vasculature. Since cancer tumours have more blood vessels than the surrounding tissue, they are distinguishable in this image.
Currently the resolution of the images is not as fine as what can be obtained with existing breast imaging techniques like X-ray mammography and MRI. Future versions are expected to improve the resolution as well as add the capability to image using several different wavelengths of light at once, which is expected to improve detectability.
The Twente researchers, who belong to the Biomedical Photonic Imaging group run by Professor Wiendelt Steenbergen, have tested their prototype in the laboratory using phantoms