MRI-powered mini-robots could offer targeted treatment

March 7, 2017, University of Houston
Aaron Becker, assistant professor of electrical and computer engineering at the University of Houston, is leading a project to develop millimeter-sized robots that can deliver drugs and other medical interventions noninvasively. Credit: University of Houston

Invasive surgical techniques - cutting through the breastbone for open heart surgery or making a large incision to inspect an abdominal tumor - allow physicians to effectively treat disease but can lead to sometimes serious complications and dramatically slow healing for the patient.

Scientists instead want to deploy dozens, or even thousands of tiny robots to travel the body's venous system as they deliver drugs or a self-assembled interventional tool. Researchers from the University of Houston and Houston Methodist Hospital are developing control algorithms, imaging technology, ultrafast computational methods and human-machine immersion methods to harness the force from a magnetic resonance imaging (MRI) scanner to both image and steer millimeter-sized robots through the body.

"We want to move from science fiction to science feasibility," said Aaron Becker, assistant professor of electrical and computer engineering at UH and principal investigator for a $608,000 Synergy Award from the National Science Foundation to develop prototypes for testing.

To tackle this unprecedented challenge, the award involves two additional investigators: Nikolaos Tsekos, associate professor of computer science and director of the Medical Robotics Laboratory at UH, who has expertise in MRI and computational methods, and Dipan J. Shah, a cardiologist and director of cardiovascular MRI at Houston Methodist Hospital, who brings expertise in clinical MRI and focusing the effort to find solutions that are clinically necessary and valuable.

While MRI has traditionally been used for noninvasive diagnosis, the next frontier is its use as a tool to offer noninvasive or minimally invasive treatment.

The milli-robot development and control work is an outgrowth of Becker's previous research, which was funded in part with an NSF CAREER award and demonstrated the theory behind the proposal. This grant, awarded through NSF's Cyber-Physical Systems (CPS) program, will fund work to build a prototype suitable for animal testing. The MRI control and follow a previous CPS award in image-guided robotic surgeries led by Tsekos and Shah.

Their current models are up to two centimeters; Becker said the goal is robots that range from 0.5 millimeters to two millimeters. The average human hair, in comparison, is about 0.08 millimeters wide.

MRI provides enough magnetic force to steer the robots through the body's blood vessels but can't penetrate tumors or other tissue. This project is working with two designs, both powered by the MRI scanner, to address that problem, one based on the principle of mechanical resonance and the second modeled after a self-assembling surgical tool, a Gauss gun.

A key issue is real-time control, Becker said, noting that blood vessels move around in the body, making it crucial to be able to see both the anatomy and the robot as it moves in order to keep it moving correctly. Even the fastest current MRI scans are too slow for such control and have a time lag before the information is available. Developing such a system is a multidisciplinary task that must seamlessly integrate sensing with the MRI scanner, milli-robot control and close the loop by controlling the scanner to drive the milli-robots.

Ultimately, Becker said, the goal is to use the power of an MRI to steer large numbers of robots throughout the body. While one milli-robot could target a single lesion, delivering chemotherapy or another intervention, that isn't practical for a late-stage cancer, for example.

"Targeting delivery with dozens of microsurgeons is my goal," he said. In this case, those "microsurgeons" would be robots, guided by a physician.

Explore further: Biomedical researchers suggest using robots to grow human tissue

Related Stories

Biomedical researchers suggest using robots to grow human tissue

March 3, 2017
(Tech Xplore)—A pair of biomedical researchers with Oxford University is suggesting that human-like robots might provide the best platform for growing tissue to be transplanted into human patients. In a recent issue of ...

Recommended for you

Surgical blood transfusions tied to clot risk

June 13, 2018
(HealthDay)—Blood transfusions around the time of surgery may raise your risk for dangerous blood clots, researchers say.

Tonsil and adenoid removal associated with respiratory, allergic and infectious disease

June 7, 2018
Tonsil and adenoid removal associated with long-term risks of respiratory, allergic and infectious diseases Removing tonsils and adenoids in childhood increases the long-term risk of respiratory, allergic and infectious diseases, ...

Clues found to early lung transplant failure

May 21, 2018
Among organ transplant patients, those receiving new lungs face a higher rate of organ failure and death compared with people undergoing heart, kidney and liver transplants. One of the culprits is inflammation that damages ...

In breakthrough, surgeon builds windpipes from arteries

May 20, 2018
Where others failed, sometimes spectacularly, French surgeon Emmanuel Martinod has helped people whose windpipes have been ravaged by cancer and other diseases to live and breathe normally again.

Blood type O patients may have higher risk of death from severe trauma

May 1, 2018
Blood type O is associated with high death rates in severe trauma patients, according to a study published in the open access journal Critical Care that involved 901 Japanese emergency care patients.

Brains, eyes, testes: off-limits for transplants?

April 28, 2018
Since the world's first successful organ transplant in 1954—a kidney—the discipline has advanced to the point where a wounded soldier could have his penis and scrotum replaced in a groundbreaking operation last month.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.