Hey, You Just Swallowed a Camera!
May 24, 2000 -- With all the hype about the marvels of wireless
communications, here's news of wireless technology that isn't too hard to
swallow. Researchers from the UK and Israel have developed a vitamin
pill-sized, wireless video camera that can be swallowed and will transmit
high-quality images of the insides of the stomach and intestines as its makes
its journey from the mouth to parts beyond. The technology is described in the
May 25 issue of the journal Nature.
When patients are having stomach or bowel problems, they must often undergo
uncomfortable imaging procedures for their doctors to determine the cause of
the problem. Standard techniques for getting good video images of the stomach
or bowels involve a flexible tube carrying a light and a miniature camera on
its tip that is passed down through the throat (gastroscopy, for viewing the
stomach) or up through the rectum (colonoscopy, for viewing the large bowel, or
endoscopy, for viewing the small bowel).
But because of the twists and turns in the digestive tract, it is often hard
for doctors to snake the tubes around bends, and they frequently have to puff
in jets of air to help the camera get through narrow passages. The procedure
causes so much discomfort that it is usually performed with the patient under
sedation or anesthesia.
In contrast, healthy human volunteers had no trouble swallowing the
so-called wireless endoscopy capsules and did not experience any stomach
problems, the researchers report. The capsules, which are pushed along through
the stomach and intestines by the same mechanism that transports food,
transmitted high-quality video images for up to six hours from the stomach,
small bowel, and cecum (a pouch located in the colon). The camera passed
through the stomach in an average of 80 minutes and through the small bowel in
about 90 minutes, and was out of the body in 10 to 48 hours.
The new device, if approved by the FDA, promises to free many patients from
the discomfort and limitations of small-bowel imaging, and to allow them to
continue daily activities while the camera works its way through the system,
possibly eliminating the need for traditional stomach- and bowel-imaging
techniques, say Paul Swain, PhD, and colleagues from the Royal London Hospital
and Given Imaging Ltd. in Yoqneam,
As it moves down through the stomach, intestines, and bowel, the camera
sends out video signals in the UHF-band. The signals are detected by antennas
that are taped to the body, and stored on portable recorders, which are capable
of recording for more than five hours, the researchers say.
"The device has a 140 degree lens which is behind a dome-shaped window.
The gut squeezes down and will open and close in on it, and we've designed the
lens to have a very short focal length so that the image will be in focus even
when the gut is actually touching the window," says Swain, a
gastroenterologist at the Royal London Hospital, in an interview with
The device, called "gulpable minicam," was made possible by
technical advances in the areas of image sensors, integrated circuits, and
light-emitting diodes that emit white light with low energy requirements. It
joins a host of other devices that are already on the market or in the late
phases of testing. These devices, some of which can be swallowed and others of
which are worn on the body, can be used to remotely monitor vital signs, such
as blood pressure, respiration rate, and oxygen levels. The devices are being
tested by the U.S. military, NASA, and elite athletes, including marathon