While modern catheters can reach into various parts of the body, navigating there remains a major challenge. Fluoroscopes that emit X-rays are used to constantly keep track of the catheter location, but they emit ionizing radiation and require a great deal of protection to be used by clinicians.
Engineers at the Fraunhofer Institute for Digital Medicine MEVIS in Bremen, Germany have developed a technology that allows a catheter to understand how it is bent, which can indicate precisely where it is along its journey.
The capability, made possible thanks to fiber optics outfitted with microscopic mirrors, works by detecting color changes as the fiber is bent. Both the direction and angle of the curve in a catheter can be calculated from how the color is affected by the tiny mirrors within the optical fiber.
All this is coupled with software that creates a 3D model of the vasculature through which the catheter will travel, gathered from CT and MRI scans. As the catheter travels through a patient who was scanned prior to the procedure, the system can match the real-time shape of the catheter to the shape of the vessel within the 3D model, identifying the location of the catheter in the vessel.
This so-called IntelliCath (Intelligent Catheter Navigation) system is yet to be tried on humans or animals, but has been shown to have a 5 mm accuracy when using silicone tubing.
If it does work well in animal models, the researchers hope to soon try the technology in humans and are already thinking of better ways to implement it, including having audio guidance that beeps depending on what’s ahead of the distal end. The researchers liken it to how modern cars help us back up into tight spots by beeping more rapidly the closer we come to an obstacle.