U.S. researchers create world's smallest endoscope

Capsule devise can be swallowed more easily, engineers say

By Kyung M. Song
The Seattle Times


University of Washington researcher Tom Johnston shows how a tiny tethered laser scanner, ingested orally, gives a view of his teeth, on January 25.
McClatchy Newspapers


Researchers at the University of Washington have developed a laser scanner that is so small it can fit inside a pill as pictured here. The diagnostic device is intended to be used to scope out cancer in the esophagus.
McClatchy Newspapers
It's one of the world's smallest devices for probing a human body: a tiny laser scanner the size of a Tylenol, tethered to an optical fiber, used to scope out cancer in the esophagus.
The flexible capsule endoscope, invented by engineers at the University of Washington, is about half the size of its nearest competitor, and it's much easier to swallow than traditional endoscopes, which are so thick that patients would gag if they weren't sedated.

But the invention's toughest hurdle may be low-tech - getting health insurers to pay for the new endoscopes.

Lack of insurance coverage has stymied sales of a competitor, the Israeli-made PillCam ESO, a camera-in-a-pill that the federal Food and Drug Administration approved for marketing in 2004. That company has estimated that 30 million Americans belong to health plans that will pay for PillCam ESO. But that's just 15 percent of the nation's insured.

Nonetheless, the University of Washington inventors are hoping they can slip their pill past the insurance companies' resistance because it would be cheaper and quicker than the PillCam ESO - and offering doctors more control.

Unlike the Israeli-made device, which is ingested and passed through the digestive tract, the University of Washington's new laser-scanner capsule can be pulled back out like a traditional endoscope, a tool that has a light attached to the end and is used to examine the body cavity or organs.

And unlike those traditional endoscopes, the University of Washington's capsule endoscope does not require anesthesia.

Ultimately, University of Washington engineers think the early benefits would be to new patients who have shied away from getting checked for esophageal cancer because of discomfort, cost or time. "This is going to bring more people to get endoscopies," said Eric Seibel, a research associate professor in mechanical engineering at the University of Washington and one of the lead inventors.

More than 15,000 Americans were diagnosed with esophageal cancer last year. Another 14,000 people died of it, according to the National Cancer Institute. White men are most susceptible. Avoiding smoking and alcohol decreases the risk of esophageal cancer.

Another risk factor is gastric reflux, when digested food or bile backs up into the esophagus and can irritate the esophagus and lead to abnormal cells that increase the likelihood of cancer. Tens of millions of U.S. adults are affected.

The University of Washington's capsule endoscope captures video images as the tiny scanner is moved up and down the esophageal tube. Such control is not possible with the untethered PillCam. The university's scope's tip is sheathed in a pill-shaped plastic cover to give it enough weight for swallowing.

However, if the scope detects abnormal cells, the patient then must get a separate biopsy. By contrast, traditional endoscopes take tissue samples simultaneously.

Lisa Norton, a technology manager with University of Washington TechTransfer which helps license faculty inventions, said the university may soon sign a production agreement with a medical-device manufacturer. Then, if the probe is approved by the FDA, it could be available for sale in a couple of years.

In the meantime, Seibel and his colleagues are thinking ahead to other potential uses for their flexible scopes. Those could include devices that can scan hard-to-reach body parts such as the pancreatic or fallopian tubes - or probe inside the farthest corners of airplane wings.

If they strike commercial success, the University of Washington would get two thirds of the profit, while Seibel and his 15 or so co-inventors would get the other third.

"It won't make us rich, but it's something that could supplement our income," Seibel said.