Physicians may soon have a new way to screen patients for Barrett's esophagus, a precancerous condition usually caused by chronic exposure to stomach acid. Researchers (Gary Tearney, MD, PhD, Michalina Gora, Ph.D., and Kevin Gallagher) at the Wellman Center for Photomedicine at Massachusetts General Hospital (MGH) have developed an imaging system enclosed in a capsule about the size of a multivitamin pill that creates detailed, microscopic images of the esophageal wall. The system has several advantages over traditional endoscopy. The inch-long endomicroscopy capsule contains rotating infrared laser and sensors for recording reflected light.
"This system gives us a convenient way to screen for Barrett's that doesn't require patient sedation, a specialized setting and equipment, or a physician who has been trained in endoscopy," says Gary Tearney, MD, PhD, of the Wellman Center and the MGH Pathology Department.
"By showing the three-dimensional, microscopic structure of the esophageal lining, it reveals much more detail than can be seen with even high-resolution endoscopy." The system developed by Tearney and his colleagues involves a capsule containing optical frequency domain imaging (OFDI) technology – a rapidly rotating laser tip emitting a beam of near-infrared light and sensors that record light reflected back from the esophageal lining. The capsule is attached to a string-like tether that connects to the imaging console and allows a physician or other health professional to control the system. After the capsule is swallowed by a patient, it is carried down the esophagus by normal contraction of the surrounding muscles. When the capsule reaches the entrance to the stomach, it can be pulled back up by the tether. OFDI images are taken throughout the capsule's transit down and up the esophagus.