Scientists at the Tokyo Institute of Technology have developed a self-propelled catheter, which can move like an earthworm and could help doctors reach areas of the lung that can be tricky to access using conventional bronchoscopes.
At the moment, if doctors want to take a closer look at the lesion in someone’s lungs, they typically use a bronchoscope. This is a thin flexible tube containing a camera, light, and other tools like forceps, that a doctor pushes down a patient’s airway and into the lungs. Bronchoscopes allow doctors to perform a variety of tasks, such as take a tissue sample from a suspected lung tumor.
However, the airways become progressively smaller and more complicated as they branch deep in the lungs. It takes a lot of skill for a doctor to operate a bronchoscope to find and manipulate lesions deep in the lung. Even choosing the right pathway through the branching airways can be difficult.
The new catheter moves like an earthworm by generating waves along its length through pressure changes in multiple segments of its body. This type of motion, a peristalsis like propulsion, allows the catheter to crawl along very narrow airways. The doctor can change the direction of the catheter’s movement, in effect choosing which airway it crawls down among a choice of several branches. The team has tested the device in a model of the lungs, with promising results.
The researchers hope to eventually incorporate a camera and other tools to allow doctors to carry out biopsies. The work has not yet been published, but was presented at the 2017 Japan Society of Mechanical Engineers Conference on Robotics and Mechatronics in Fukushima, Japan.
See the system in action in the following video: