Gavriel J. Iddan

Wireless capsule endoscopy

We have developed a new type of endoscopy, which for the first time allows painless endoscopic imaging of the whole of the small bowel. This procedure involves a wireless capsule endoscope and we describe here its successful testing in humans.

Wireless capsule endoscopy of the small bowel: development, testing, and first human trials

Small bowel endoscopy with existing endoscopes is limited by problems of discomfort and the technical difficulty of advancing far into the small-bowel. Our aim has been to develop and test wireless capsule endoscopy. Wireless endoscopes, in the form of capsules (11 x 33 mm), were constructed by Given Imaging. These were powered by silver oxide batteries and each contained a CMOS imaging chip and miniature processor, white light emitting diodes (LEDs), a short focal length lens, and a miniature transmitter and antenna. Two video frames per second were transmitted, using radio-frequency (approx. 410 MHz), to an array of aerials attached to the body. The array of aerials can also be used to calculate the position of the capsule in the body. The images were stored on a portable recorder carried on a belt and subsequently downloaded for analysis. The batteries allow more than 5 hours of recording, although the capsule generally passes through the whole small bowel in under two hours. Clear video images of the human bowel were recorded from the pylorus to the caecum. Wireless endoscopy, for the first time, allows painless optical imaging of the whole of the small bowel.

A Short History of the Gastrointestinal Capsule

The origin of work on the gastrointestinal (GI) capsule can be traced back to 1981. At that time, I was on a sabbatical leave from my work as an electro-optical engineer at Rafael, a government defense lab in Israel, and was working in the United States for a medical instrument company in Boston, Massachusetts. A gastroenterologist friend, Prof. Eitan Scapa, explained to me some of the shortcomings of the fiber bundle endoscope, especially its rigidity and its inability to view the small intestine. At that time, I had no idea as to how to solve these intriguing and interesting problems.