A new non-mechanical optical coherence tomography (OCT) device developed by researchers at the University of Colorado Boulder could reshape how clinicians image delicate structures like the retina in the eye and coronary vessels. By eliminating moving components, this next-generation scanner not only improves reliability but also opens new doors for miniaturized imaging inside the body, including for heart disease detection.
OCT—a non-invasive imaging technique that uses light waves to capture high-resolution, cross-sectional views of tissue, is widely used for diagnosing eye diseases.
The team’s innovation, detailed in Optics Express, uses electrowetting-based liquid lenses to steer light, replacing traditional scanning mirrors. Because the lens shape changes using an applied voltage rather than moving parts, it reduces mechanical failure points and significantly cuts down on power consumption—an advantage for portable or implantable medical devices.
“The benefits of non-mechanical scanning is that you eliminate the need to physically move objects in your device, which reduces any sources of mechanical failure and increases the overall longevity of the device itself,” said lead author Samuel Gilinsky, PhD in electrical engineering.
The prototype device successfully captured subcellular-resolution images of zebrafish eyes—an established model for human ocular anatomy. The images clearly resolved key anatomical landmarks like the cornea, iris, and lens, achieving resolution benchmarks comparable to commercial OCT systems.
From retinas to coronary arteries
OCT is already a mainstay in ophthalmology, enabling non-invasive, real-time imaging of the retina for conditions like macular degeneration and diabetic retinopathy. But its clinical reach has been limited by the size, power demands, and fragility of conventional devices that rely on spinning mirrors for beam control.
By contrast, CU Boulder’s electrowetting scanner—built with no moving mechanical components—can be scaled down into flexible endoscopes or wearable devices. This could expand OCT’s use beyond eye clinics into cardiology, neurology, and even at-home monitoring.
The device’s compactness and reduced power requirements also make it well-suited for integration into minimally invasive surgical tools, such as ultra-thin catheters used in cardiovascular imaging. Gilinsky noted the potential for mapping coronary vessel walls, helping detect early signs of atherosclerosis, the root cause of most heart attacks and strokes.
“This could be a critical technique for in vivo imaging for inside our bodies.” said Gilinsky.
A zebrafish eye opens the door
To validate their system, the researchers imaged zebrafish eyes in vivo—a crucial step given the similarities in ocular anatomy. They found that their system could reliably delineate ocular layers, indicating the optical steering was stable and precise enough for real-world biological imaging.
Zebrafish models also enabled the team to test the system’s dynamic range and contrast, key parameters for clinical translation. “Our work presents an opportunity where we can hopefully detect health conditions earlier and improve the lives of people,” said co-author Juliet Gopinath, PhD, professor of electrical engineering.
What’s next?
The team is now focused on translating the device into clinical prototypes. Funded by the Office of Naval Research, NIH, and NSF, their roadmap includes developing flexible endoscopes for retinal and cardiac imaging, potentially replacing bulkier systems used today.
“There is a growing push to make endoscopes as small in diameter and flexible as possible to cause as little discomfort as possible,” Gilinsky said. “By using our components, we can maintain a very small-scale optical system compared to a mechanical scanner that can help OCT technologies.”
If successful, this OCT platform may bring a new class of non-invasive diagnostics closer to the bedside—and eventually, into wearable or implantable devices for real-time health monitoring.