• 1/26/2008
  • London, England
  • Roger Highfield
  • Telegraph.co.uk

A “camera in a pill” that can be swallowed whole to check for warning signs of cancer is being tested by American doctors.

The capsule measures one quarter of an inch by three quarters, small enough to be comfortably swallowed, and creates a high-resolution colour picture of a person’s insides.

Devised by a team at the University of Washington, Seattle, the pill records 15 colour images every second. It is attached to a tether which allows doctors to control more accurately what they view than with previous devices.

Its first use will be to screen for signs of oesophageal cancer – cancer of the gullet. The disease is currently diagnosed in around 8,000 people annually in the UK.

“This could be the foundation for the future of endoscopy,” says lead author Dr Eric Seibel, whose findings will be described in the journal IEEE Transactions on Biomedical Engineering.

Oesophageal cancer is linked to smoking and drinking and often follows a condition called Barrett’s oesophagus, a change in the gullet lining. This can be healed, avoiding the cancer that results in around 10 per cent of cases.

But because internal scans are expensive, most people don’t discover they are affected until it has progressed to cancer. By that stage the survival rate is less than 15 per cent.

Even though the camera’s single eye sees only one spot – pixel – of the image at a time, it combines all the information as it swings around at 5,000 times per second to build up a high-resolution picture.

The device is half as big as a rival that is about the width of an adult fingernail and twice as long. And the conventional pill widely used for “capsule endoscopy” offers only a single fly-by view before it is excreted up to 72 hours later.