Location-aware ingestible microdevices monitor gastrointestinal environment

Gastrointestinal (GI) tract motility disorders such as gastroparesis, incontinence and constipation affect more than one-third of the population globally. Currently, techniques like nuclear studies, endoscopy, manometry, and radiologic studies are the gold standard to understand, monitor and treat such disorders. However, these procedures are invasive, often involve potentially harmful X-ray radiation, and require repeated evaluations in a hospital setting. Alternatives like video capsule endoscopy are less invasive but lack direct measurement of the capsule’s location in the GI tract.

Researchers from Brigham and Women’s Hospital, in collaboration with engineers at MIT and Caltech, developed a platform for localizing and tracking wireless microdevices with millimeter-scale spatial resolution inside the GI tract in real time and in non-clinical settings, without any X-ray radiation. They were able to achieve this by generating three-dimensional magnetic field gradients in the gastrointestinal field using high-efficiency planar electromagnetic coils that each encoded a point in space with a distinct magnetic field. They tested the coils in an in vitro saline tank to confirm the theoretical localization resolution. Then they tracked the coils in swine models and found the system was a highly accurate indicator of defecation.

“Here we report the three-dimensional localization and tracking of wireless ingestible microdevices in the gastrointestinal tract of large animals in real time and with millimeter-scale resolution,” said corresponding author Giovanni Traverso, MD, PhD, MBBCH, Division of Gastroenterology, Hepatology and Endoscopy at the Brigham. “Such a portable and non-invasive procedure holds the potential for significant clinical benefit without causing patients discomfort.”

Read more in Nature Electronics.