Undergoing surgery is rarely a pleasant experience and can sometimes be very invasive. Surgical procedures have constantly evolved over the centuries, growing with knowledge of anatomy and biology.
Innovative methods have also been enhanced by new tools, and the growth in the use of robotics since the 1980s has significantly advanced healthcare. Assistant Professor Zhenhua Tian has taken a further step in progress using robotics and non-invasive acoustics, and his team’s work has been published in Science Advances.
Robot assisted surgery
Surgery using robots has been invasive since its invention because it involves cutting and other instruments are often inserted into the incision. However, because robot-assisted tools can be smaller, the cuts also tend to be smaller than those in traditional surgeries, making robotics the preferred option. This form of surgery has proven benefits and its use has increased over time, with advantages for patients including
- Less discomfort and bleeding.
- Less time in the hospital
- Faster recovery periods
In fact, according to the American College of Surgeons, 1.8 percent of surgeries included a robot in 2012. By 2018, that percentage had increased to 15.1 percent and continues to rise thanks to advances in robotics. Some of the most common procedures involving robotics include appendectomies, hysterectomies, and gastric bypass.
Non-invasive sound treatment
While robot-assisted surgery has its advantages, Tian’s team has taken that idea a step further from its current state: Team members are developing a method to move small targets, such as cells and drugs, within a body which is not invasive. That means the method requires no cutting.
The secret lies in the acoustic energy emitters that Tian’s team uses to surround and capture particles, functioning like invisible tweezers. The emitters create 3D acoustic vortex fields that can pass through barriers such as bones and tissues, crossing each other to form small ring-shaped acoustic traps. Micro- to millimeter-sized objects trapped in the center of an acoustic trap can be moved and rotated. Tian received the 2024 National Science Foundation Faculty Early Career Development Program (CAREER) Award for the development of the acoustic vortex.
“The ability to move cells and drugs within veins without breaking the skin creates new opportunities in medicine,” Tian said. “As we continue to work on this research, I anticipate that we will find a host of new applications.”
By mounting an acoustic vortex emitter on a robotic platform, the acoustic vortex beam can be moved at the micrometer scale. Consequently, the particle capture area can be precisely set in 3D space and the motion of a particle after its capture can be engineered. When moving a small object along the sinuous path of a blood vessel, this can be a critical feature.
More than medicine
While Tian’s team can move a small object behind a solid structure, acoustic vortex beams can also move particles within gases and liquids. Although the current approach targets small particles within those substances, integrating acoustic energy emitters with robotics has applications beyond surgery and very small particles. Contactless robotic manipulation has potential in many other applications in engineering, biology, and chemistry research. Some of them include
- Controlling microrobots
- Manipulation of delicate bioparticles, such as exosomes and cells.
- Transport of hazardous reagent droplets
- Control of self-assembly of colloidal materials.
- Arrangement of nanomaterials for the manufacture of composites.
“When we recently participated in a STEM exhibition, the children who visited us enjoyed putting small beads in the invisible acoustic fields generated by our devices, but we would like to offer them the opportunity to move larger objects,” Tian said. “Next year, we hope to have a larger emitter that can hold a ping pong ball. It will be interesting to see how we incorporate that approach into our other research.”