In rare instances, the impressiveness of an innovation or technology needs no imminent application to justify its inherent impressiveness. That is the case when it comes to millimeter-scale robots, or milli-robots, that have proven capable of using an MRI-provided magnetic field to move through the human body.
The technology, more specifically known as magnetic hammer actuation, is cased inside of a bullet-shaped millirobot, and thus far has been tested on the internal tissues of lambs and goats.
Though potential applications have been given, including ‘highly localized drug delivery’ and minimally invasive surgery, such applications do not lie in the immediate future. That does not make the technology any less impressive or potentially useful, even if it will take a significant amount of time for clinical use.
The millirobots created by a Houston-based team are akin to ‘magnetic hammers’ that can be pushed and pulled through crevices in the body with assistance from the magnetic field. A bead made of stainless steel is pulled in one direction by the field, compressing a spring that pushes the transparent acrylic body forward when released.
Yet critics of the particular study being referenced, claim that specific, major surgeries that could be replaced by this potentially useful technology have yet to be cited.
They have an exciting technology looking for an application, Dr. Sylvain Martel of Polytechnique Montreal says.
Contrarily IEEE, which commissioned the study, envisions this technology being capable of carrying out tasks such as popping a cyst that lies on the spinal cord or biopsies as close-range targets. In a more ambitious view, they envision these milli-robots entering the spinal canal and traveling to the brain via the flow of cerebrospinal fluid to alleviate symptoms of conditions such as hydrocephaluss.
Hydrocephalus, among other conditions, is a candidate for correction by our milli-robots because the ventricles are fluid-filled and connect to the spinal canal, Aaron Becker, electrical and computer engineering professor at the University of Houston said. Our noninvasive approach would eventually require simply a hypodermic needle or lumbar puncture to introduce the components into the spinal canal, and the components could be steered out of the body afterwards.
Becker is working with Nikolaos Tsekos, associate professor of computer science and director of the Medical Robotics Laboratory at UH and Dipan J. Shah, a cardiologist and director of cardiovascular MRI at Houston Methodist Hospital on figuring out how to control these millirobots more precisely using an electric field, specifically magnetic resonance imaging (MRI) machines.
Currently, treatment for conditions such as hydrocephalus require drilling through the skull. If perfected, this new technology could allow doctors to deploy ‘dozens, or even thousands of tiny robots’, while simultaneously scanning the body in the way that MRI machines are traditionally used.
Still, concerns about the technology remain. Should the mechanisms within the millirobot fail, removal may require the same invasive surgery that served as the impetus for the milli-robots’ usage in the first place. Additionally, the Houston-based team – working in collaboration with Pierre DuPont from Harvard Medical School and Ouajdi Felfoul at Boston Children’s Hospital – acknowledge that they are still very much in the conceptual stage, though they were awarded $608,000 in funding as part of the Synergy Award from the National Science Foundation to develop more prototypes.
Though application is not imminent, Becker sees the systems in place and the promise of the technology as ample reason to be optimistic, if not persistent in his research.
The benefit of our research is that we can now create clinically relevant forces inside a standard MRI scanner, using just the MRI magnetic field, Becker said. Targeting delivery with dozens of microsurgeons is my goal.