Researchers from the University of Sheffield and Boston’s Children Hospital, with its ties to Harvard Medical School, have developed a robot that can be implanted into the body to aid treatment of esophageal atresia, a rare birth defect that affects the body’s esophagus.
Dr. Dana Damian from the Department of Automatic Control and Systems Engineering at the University of Sheffield and her team from Boston Children’s Hospital have created a prototype robotic implant that encourages tissue growth in babies.
The robot is a small device attached to the esophagus by two rings. An incorporated motor stimulates the cells by gently pulling the tissue displacement. The robot then monitors and applies tissue traction depending on the properties of the tissue.
The robot’s function is inspired by the Foker technique of correcting the esophageal atresia. This involves manually pulling the tissue slowly using sutures over a period of time.
"Doctors have been performing the Foker procedure as they realized that tissue lengthening can be achieved by pulling on the tissue. However, it is unknown how much force should be applied to produce tissue lengthening. Although the technique is one of the best standards, sometimes the sutures surgeons attach to the esophagus can tear which can result in repetitive surgeries or scar tissue can form that can cause problems for the patient in the future” said Dr. Dana Damian
"The robot we developed addresses this issue because it measures the force being applied and can be adapted at any time throughout the treatment. With it being implanted in the patient, it means they have – in effect – a doctor by their side all the time, monitoring them and changing their treatment when needed," she continued.
Esophageal atresia is a rare genetic disease that affects one in 4,000 babies born in the U.S. and Europe. It occurs when the upper and lower parts of the esophagus don’t connect. This means that food cannot reach the baby’s stomach. Some of these cases are characterized by a gap of three to 10 centimeters between the esophageal stubs. This gap is called long gap esophageal atresia. Treatment using the Foker technique can start as early as three months old. The treatment can take months and usually the patient is sedated to ensure that the sutures in place don’t tear.
The study proposes the robot will allow babies to move freely and interact with their parents while undergoing the treatment. This would relieve some of the stress for both parties.
The implant is powered by a control unit that is attached to a vest outside of the body, allowing doctors to monitor the patient without impacting the baby’s daily routine.
Dr. Damian said, “The biggest challenge we faced was to design a robot that works in a technology-hostile environment and to develop a robust physiologically relevant interaction with the tissue that promotes its growth when there are so many unknowns about the underlying mechanisms. The robot we designed had to be soft and durable, air and water impermeable, abrasion resistant, non-corrosive and be able to be implanted for long-term treatment. This is the first step in adaptive regenerative-based treatments of tissues. We have made a device that can provide long-term control of the tissue growth using onboard medical expertise. We further want to look at other tubular tissues, such as the intestine and the vascular system, to see if this sort of technology can be used to help with other conditions, such as Short Bowel Syndrome."
Tissue growth has been an issue in the bioengineering field for years. But this research brings scientists a step closer to understanding how mechanical stimulation at the tissue level helps the cells multiply and how doctors can stimulate cells to grow using intuitive tools.
The research has shown that cells will multiply in response to being pulled rather than stretching out of shape or scarring. Using the robot’s monitoring and control abilities, the treatment can be adjusted to suit the patients and to optimize cell growth.
Sheila MacNeil, professor of tissue engineering in the Department of Materials Science and Engineering at the University of Sheffield said, “The development of this robotic implant is a breakthrough in applying the knowledge that tissues respond to strain with the production of new tissue in a practical and clinically useful manner.”
The paper on this research was published in Science Robotics.