Capsule endoscopy was developed around the year 2000 to allow for visual diagnostics of the small bowel. These capsules, now also developed for esophageal, gastric, and colon use, passively move through the digestive system and, as is the case in the most prevalent devices, captures image frames and transmit them to a receiver belt that is worn by a patient. These capsules are noninvasive and favorable for a patient, however, are limited in their ability to target lesions for viewing and do not have the capability for intervention, thus, must be followed up by more invasive tools if issues are found. Capsules have become a gold standard for small-bowel screening owing to the diameter of the bowel being small enough for a capsule to move through smoothly. In other areas along the GI tract, the diameters may be larger, and thus capsules tend to tumble resulting in viewing of limited tissue surface areas.

Actuation of capsules via magnetic fields has been investigated since the early 2000s. Magnetics, especially when using permanent magnets, carry benefits of not needing actuation mechanisms in the limited spaces of capsules as well as not needing additional power. The focus of my Ph.D. work has been the application of magnetic actuation strategies to improve the mobility of magnetically actuated capsules, with or without a tether. Adding mobility requires the application of magnetic force and torque by manipulating an external magnetic field (torque) and its gradient (force). With the use of magnetic localization, I have been working on closed loop control navigation that consists of using position and orientation feedback from devices in the body to better estimate necessary forces and torques to achieve desired user motion.

With the Sonopill consortium, I have worked to improve mobility of therapeutic devices in the GI tract with the use of magnetic fields. The multidisciplinary background of the group has allowed for technology development that is driven by expertise from clinicians as well as mechanical, electrical, and robotics engineers. Such collaboration has served as a pathway to developing technology that we anticipate will have clinical impact in the near future. In coming months, we will be conducting further testing on our latest therapeutic device with our eyes set on human applications in coming years.

First published: 16 January 2018

<< Blog