Specialized imaging technique offers pain-free, effective alternative to mammograms
A new photoacoustic CT, or PACT, imaging technique is said to perform as well as mammography at cancer detection, but without the discomfort of standard mammograms.
That’s according to new work published in Nature Biomedical Imaging detailing the efforts of a Caltech-led team seeking to develop a more patient-friendly way to screen for breast cancer. According to the team’s recent analysis, PACT performs just as well as both mammography and MRI in differentiating between suspicious and normal tissue. Experts involved in its development say their method, which is both accessible and affordable, addresses some of the shortcomings of current screening methods.
“We were strongly motivated to work on this problem because none of the current techniques are perfect," explained Lihong Wang, the Bren Professor of Medical Engineering and Electrical Engineering at Caltech. "The future of medicine has to be better than that."
PACT makes use of an infrared laser-sonic scanner that combines light and ultrasound to acquire high-resolution images that detect tumor-related vasculature changes. The laser diffuses through the breast and is then absorbed by molecules, which vibrate when exposed to ultrasonic waves.
"We use light to see the molecules, but we use sound to define the spatial location. We basically use molecules to figure out the body's physiology," Wang explained. "That's the beauty of photoacoustic tomography: By detecting molecules, we can figure out exactly how the body is functioning. When there's a functional difference, that means we can potentially detect disease better."
In recent clinical testing on a group of 39 women, PACT ably differentiated between normal and suspicious tissue, achieving an area under the receiver operating characteristic curve of 0.89, while also accurately distinguishing between benign and malignant lesions. The team suggested the method’s accuracy yielded results in line with that of standard breast imaging techniques.
Researchers have been working to craft the technique for more than two decades and have refined it to the point where it can now capture what they say is diagnostic quality imaging in as little as 15 seconds. Recently, the team deployed machine learning techniques to further improve PACT’s ability to detect subtle abnormalities.
The group is now planning to conduct additional studies of PACT on larger sample sizes.
Learn more about their work here.
In addition to her background in journalism, Hannah also has patient-facing experience in clinical settings, having spent more than 12 years working as a registered rad tech. She began covering the medical imaging industry for Innovate Healthcare in 2021.