Researchers at St. Louis’ Washington University’s School of Medicine have developed a technology which they claim could significantly improve tumor removal procedures, especially breast cancer procedures.
A study based on the imaging technique was published this week in the journal Science Advances.
The imaging technique, dubbed photoacoustic imaging, will require significantly less time than current techniques, which require a day or more to perform, according to the study. Researchers in the study are hopeful they could bring the timeframe for their scans down to as low as 10 minutes.
“Right now, we don’t have a good method to assess margins during breast cancer surgeries,” Dr. Rebecca Aft of the Barnes-Jewish Hospital and Washington University School of Medicine said in prepared remarks. “One day we think we’ll be able to take a specimen straight from the patient, plop it into the machine in the operating room and know in minutes whether we’ve gotten all the tumor out or not. That’s the goal.”
Currently, after surgeries specimens are sent to pathologies, who slice, stain and inspect the margins of the tumor for malignant cells to determine whether the entire tumor has been removed. This process can take days, and lead to extra procedures if malignant cells were not excised correctly.
Researchers used a phenomenon known as the photoacoustic effect, through which energy detectable by ultrasound technology is absorbed by molecules after being exposed to a beam of light of a particular wavelength.
“All molecules absorb light at some wavelength. This is what makes photoacoustic imaging so powerful. Essentially, you can see any molecule, provided you have the ability to produce light of any wavelength. None of the other imaging technologies can do that. Ultrasound will not do that. X-rays will not do that. Light is the only tool that allows us to provide biochemical information,” co-senior author Lihong Wang said in a prepared statement.
To test the device, researchers imaged and stained samples of 3 tumors from breast cancer patients, and found that the imaging technique provided detailed results.
“This is a proof of concept that we can use photoacoustic imaging on breast tissue and get images that look similar to traditional staining methods without any sort of tissue processing,” co-senior author Dr. Deborah Novack of Washington University said in a press release. “It’s the pattern of cells – their growth pattern, their size, their relationship to one another – that tells us if this is normal tissue or something malignant. Overall, the photoacoustic images had a lot of the same features that we see with standard staining, which means we can use the same criteria to interpret the photoacoustic imaging. We don’t have to come up with new criteria.”
Researchers are now working on developing a system that operates faster, hoping to reduce scanning time to 10 minutes.
“We expect to be able to speed up the process. For this study, we had only a single channel for emitting light. If you have multiple channels, you can scan in parallel and that reduces the imaging time. Another way to speed it up is to fire the laser faster. Each laser pulse gives you one data point. Faster pulsing means faster data collection,” Wang said in a prepared release.