Pill-sized device uses spinning laser to image the esophagus
By Ben Coxworth
January 15, 2013
Barrett’s esophagus is a precancerous condition typically caused by chronic exposure to stomach acid, and is usually diagnosed by inserting an endoscope down the patient’s throat. A tool has been developed, however, that should allow for a quicker, easier way of getting a good look at such peoples’ esophagus – it’s a swallowable capsule that contains a spinning laser.
The device was created by a team at the Harvard University-affiliated Wellman Center for Photomedicine at Massachusetts General Hospital, led by Prof. Gary Tearney.
The transparent capsule is “about the size of a multivitamin pill,” and is attached by a thin tether to an imaging/control console. Contained within the capsule is an optical frequency domain imaging (OFDI) system, which incorporates a rapidly-spinning near-infrared laser. As the beam swings around, it strikes the adjacent esophageal lining and is reflected back into the capsule, where photosensors detect it. Using that reflected light, a highly-detailed 3D map of the lining is created.
According to Tearney, the microscopic-scale images reveal “much more detail than can be seen with even high-resolution endoscopy.”
Additionally, the capsule can simply be swallowed by the patient and carried down the esophagus by normal muscle contractions, then retrieved by pulling on its tether. Images are acquired both on the way up and down. The patient doesn’t need to be sedated, no special lab or extra equipment is required, and the person administering the procedure doesn’t need to be trained in endoscopy.
It’s also fast. Whereas a typical endoscopic examination reportedly takes about an hour and a half, the capsule can image the entire esophagus in less than one minute – a more complete examination, involving two passes up the esophagus and two down, takes about six minutes.
Test subjects who have tried the new procedure, and who have previously had experience with traditional endoscopy, state that they prefer the capsule.
Source: Harvard University