Junjie Yao: Listening into the Body through Light

Junjie Yao has joined the faculty of the Biomedical Engineering Department in Duke University’s Pratt School of Engineering. A pioneer in the emerging field of photoacoustic tomography (PAT)—a powerful new imaging technology—Yao will bring together Duke’s expertise in clinical photonic and ultrasound applications to study the brain as well as develop new cancer diagnostics and therapies.

As the two terms in photoacoustic tomography implies, the technology combines the imaging capabilities of photons and ultrasound waves.

And that ultrasound wave carries a lot of valuable information about the tissue.

“PAT has two major advantages, unique scalability over a wide range of sizes and the strong ability to gather functional and molecular information,” said Yao, who comes to Duke from a postdoctoral research associate position at Washington University in St. Louis, where he also earned his PhD. “A lot of other imaging technologies like X-ray, CT or MRI mostly provide large-scale anatomical images. But this technology can image at length scales from a single cell all the way up to an entire body, and it can pull functional information about a tissue’s composition.”

If Yao’s research’s main title is photoacoustic tomography technology, then, he says, his work has three main subtitles.

The first is in functional brain studies, especially for fundamental neuron science. Yao plans to develop imaging technologies that interact with different elements within the brain, such as neurons, blood vessels and other supporting structures. By developing wearable devices for small animal models, PAT can precisely map their neural network and determine what neurons respond to various external stimuli.

The second two subtitles have a common theme—cancer. PAT can provide a variety of anatomic and functional information, such as where a tumor is and whether or not a treatment worked as well as planned. But it can also be the treatment itself by guiding a surgeon’s hand during surgery or precisely controlling the temperature rise of a deep-tissue tumor to kill the cancerous cells.

“It’s safe to say that PAT is still in its early stage because most of the work is still focused on technology development,” said Yao. “But the field is developing fast and people are trying hard to push the technology into health care and hospitals, which is what I hope to accomplish at Duke.”

Yao says that a big draw for him to come to Duke is its strengths in both ultrasound and optical imaging. Faculty members like Gregg Trahey, Kathy Nightingale and Olaf Von Ramm have spent the past decade developing ultrasound imaging techniques and devices that are currently being used in clinical settings. And others, like Joe Izatt, Adam Wax and Sina Farsiu have developed optical coherence tomography for surgical eye procedures, low-coherence optical spectroscopy to observe cellular structure, and advanced signal and image processing methods to improve the optical imaging quality, respectively.

“All of these optical and ultrasound imaging researchers are going to be my best friends,” said Yao. “There’s nowhere else that has such strong resources in both fields, and I want to connect them even more deeply. And I love to work with physicians, so having a strong medical school just across the street is exciting because this type of technology development cannot be successful without their input and help.

“I’m very excited to get to Duke as soon as possible to start my work,” continued Yao. “All the students are excellent. I’ve been very impressed by their motivation in research and strong interest in science. I think Duke will be a perfect place to begin as a junior faculty member. I’ll be starting the photoacoustic imaging program from zero, but with fantastic students and collaborators I think we can do something great.”