Dutch researchers from the University of Twente and Medisch Spectrum Twente Hospital in Oldenzaa have been investigating photoacoustic technology as a new imaging modality in detecting breast cancer tumors. The Twente Photoacoustic Mammoscope (PAM), a device that uses lasers to generate sound waves within the breast, has shown the ability to identify malignant tumors. According to the study abstract, “In all malignant cases, the PA contrast of the abnormality was higher than the contrast on x-ray mammography.”
The PAM device projects a laser beam into a breast, heating up areas having more hemoglobin faster than the rest of the tissue. The temperature gradient in turn creates a physical expansion of the region, which propagates in the form of a sound wave through the breast. An ultrasound detector is then used to spot the source of these waves, pinpointing the location of a malignant tumor.
From an announcement by the Optical Society of America:
By comparing the photoacoustic data with conventional diagnostic X-rays, ultrasound imaging, MRI, and tissue exams, the researchers showed that malignancies produced a distinct photoacoustic signal that is potentially clinically useful for making a diagnosis of breast cancer. The team also observed that the photoacoustic contrast of the malignant tissue is higher than the contrast provided by the conventional X-ray mammographies.
In looking to the future, notes Heijblom, “PAM needs some technical improvements before it is a really valuable clinical tool for diagnosis or treatment of breast cancer. Our next step is to make those improvements and then evaluate less obvious potential tumors, benign lesions, and normal breasts with it.”