April 16, 2025 | Magnetic flexible endoscopes (MFEs) have up to now had a few disadvantages limiting their use inside the human body for performing virtual biopsies, notably navigation-related difficulties related to their traditional cylindrical shape. These robot-assisted devices use magnetic forces to propel and maneuver through lumens like the colon, but rotation happens in only two directions that limits the scope's ability to effectively perform procedures, according to Nikita Greenidge, postgraduate researcher and member of the Science and Technologies of Robotics in Medicine (STORM) Lab at the University of Leeds (UK).
But her “chance” encounter with the oloid shape, discovered in 1929 for mathematical purposes, could enhance the cancer-detecting capabilities of MFEs, she adds. Integrating part of that shape into the top half of an existing cylindrical device enabled researchers to get it rolling through the colon of pigs (Science Robotics, DOI: 10.1126/scirobotics.adq4198).
This was a first in terms of the robot’s oloid shape and performing three-dimensional (3D) ultrasound deep in the gastrointestinal tract, says Greenidge. The mini medical robot has many potential medical applications beyond the colon, including the esophagus, lung, and small intestine—all of which are now being actively investigated in the STORM Lab.
It could be deployed to any circular space in the body with a minimally invasive point of entry. But the technology first needs to be miniaturized to fit into these significantly smaller lumens, she adds.
The magnetic robot used in the current study was 3D-printed out of resin and is roughly the size of a U.S. nickel. It is controlled by an external permanent magnet that causes it to sweep the colon scouting for lesions, allowing them to be removed as they’re found, says Greenidge.
Navigation is assisted by images from the scope’s embedded camera and magnetic localization system. The robot’s attached probe is a high-frequency micro-ultrasound array that creates a high-resolution 3D reconstruction of the area it scans, revealing features (e.g., abnormal growths, inflamed tissue, ulcers, bleeding, and polyps) on a microscopic level.
From this virtual reconstruction, clinicians make cross-sectional images that mimic those generated by a standard biopsy, Greenidge explains. This all happens in real time.
For now, the work is being done on a research level and not on one comprehensive device, but that’s the goal, she says. The hope is to start clinical trials in 2026. A parallel line of research is ultrasound-triggered drug delivery where soundwave energy is used to activate an injected therapeutic.
The clinical need being met here is one of convenience and timing, since diagnosing colorectal cancer typically requires taking a tissue sample, sending it to a lab for analysis, and waiting a week or more for the results. Combining advanced robotics with medical ultrasound imaging allows doctors to look for problems and remove any lesions that are found, as with a standard colonoscopy, but MFE technology makes the procedure more comfortable, less invasive, and easier to perform.
The oloid shape was unearthed nearly a century ago by German mathematician and sculptor Paul Schatz in his quest for a tumbler that would mix but not damage its contents, says Greenidge. She happened upon the “funky shape” a few years ago in a paper about a computer game, after being charged with figuring out how to make a magnetic robot wirelessly roll by her Ph.D. supervisor Pietro Valdastri, Ph.D., professor and chair in robotics and autonomous systems and director of the STORM Lab.
It was 2021 and Valdastri had just cofounded Atlas Endoscopy, a Leeds-based company spun out of the STORM Lab, the culmination of more than a decade of work on a general platform for robotic colonoscopy without ultrasound capabilities that began in Itay and extended to the United States. A phase 1 trial of the MFE for colonoscopies launched at Vanderbilt University Medical Center (Nashville) in 2023.
Meanwhile, researchers in the STORM Lab proceeded with translation of the odd geometric shape to the conundrum of how to get a magnetic robot to rotate on its axis—and not just left to right or up and down, Greenidge says. Thinking about how a corkscrew operates to open a bottle of wine, they were convinced they could couple those motions for their tiny robot. And so, the strange-rolling oloid was successfully leveraged to allow magnetic manipulation in all three directions of rotation.
Robotics development and integration of the probe happened at the University of Leeds, she notes. Postdoctoral researcher Benjamin Calmé, an engineer and medical doctor, led the 3D reconstruction component and used his clinical knowledge to design the interactive interface for the clinicians to use.
The University of Glasgow and University of Edinburgh provided the ultrasound probe and led the imaging component, she adds. Having multidisciplinary teams was crucial to their ultimate common achievement.
The development of an oloid magnetic endoscope could help address some colonoscopy-related gender disparities that affect both endoscopists and patients, Greenidge reports. Existing MFEs were “designed for a larger male hand and so it can be quite difficult physically for female endoscopists to use the devices properly.” The new robotics system was designed with a much smaller joystick to be comfortable for a wider range of hand sizes.
Researchers hope the system will also alleviate some of the related problems on the patient's side. Colonoscopies are more difficult to perform in women for several reasons, says Greenidge, including the fact that they tend to have a longer colon packed into a smaller and more crowded abdominal cavity that can be challenging to navigate.
Atlas Endoscopy will initially be focused on gaining approval from the U.S. Food and Drug Administration to market the general platform. Meanwhile, basic research work on an oloid magnetic endoscope with the embedded ultrasound capabilities will separately continue in Leeds’ STORM Lab. It is yet to be decided how these add-ons might eventually be integrated into the Atlas system, she says.