By: Jean Johnson for Reflux1A worm-like robot crawling around our gastrointestinal tract may sound gross, but before we dismiss the prototype diagnostic tool European scientists have developed, we might consider the alternatives.
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Prepare Yourself
The National Institutes of Health advises patients to expect the following questions from your physician on GI bleeding:
When did it start?
Is it off-and-on or does it continue?
What did you notice?
Were there black tarry stools or was there obvious blood in the stools?
Were you vomiting blood?
Did you vomit material that looks like coffee grounds?
Have you ever had a history of peptic ulcer or duodenal ulcer?
Have you ever had symptoms like this before?
What other symptoms do you have?
Did you notice anything that you think may have caused the bleeding?
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Indeed, even contemplating the GI tract isn’t exactly tops on people’s agenda. The tender tubing of the esophagus. The acidic cauldron of the stomach complete with the contents of that last snack. The feet upon feet of intestines where, deep within the dark recesses of the unfathomable gut, the body draws sustenance from what we consume. More, when something goes amiss within the mouth-to-anus pathway and patients turn to their physicians for help, a quick canvas of the tests that are ahead can make an otherwise reasonable individual shudder.
Endoscopy is the big one. It’s done with a medical device consisting of a camera mounted on a flexible tube that is inserted through either end – the mouth or the anus. Such fun even though sedatives are used to make the procedure tolerable. Also, for the examination of the upper GI tract, patients may be asked not to eat or drink for a period of time prior to seating themselves on the exam table. And for the lower, clearing the colon with laxatives or enemas may be the requisite routine. Ah yes, leave it to the body to keep us humble.
In the last five years doctors have started using a pill-sized camera device for endoscopy, rather than a camera on a flexible tube. The advantage to the PillCam, as it is called, is that you can swallow the capsule and wait for it to transmit pictures of your innards – sedation free, and you don’t need to collect and return the capsule. As of now the PillCam is FDA approved for diagnostics of the esophagus and small intestine
Then there are the barium procedures – either the barium swallow or the barium enema that coats the lining of whichever end of the GI tract is in question so that the organs are visible on X-ray images. What a blast.
At least there’s the noninvasive CT scan these days which generates a collection of black and white images showing cross-sections of the body, and hence, useful to some degree in diagnosing GI problems. But physicians need more detailed information to identify most problems, so they often use the endoscope to explore the nether regions of the gut, probing into the colon as they do in a colonoscopy or penetrating the last end of the large intestine as they do in a sigmoidoscopy. Expect no pain, the experts say. Just a little cramping here and there, or feeling like you need to have a bowel movement. No problem at all.
Given all the earthy details of the traditional diagnostic tests, a worm-like robot can sound like a real friend. Certainly its developers think the critter has much to offer – if it can navigate the years of testing still needed to ensure its safety and reliability for humans.
“Worms have locomotion systems suited to such unstructured, slippery environments,” Arianna Menciassi, a roboticist from the Sant’Anna School of Advanced Studies in Pisa, Italy, told the New Scientist in July 2006. “We turned to biological inspiration because in the peculiar environment of the gut, traditional forms of robotic locomotion don’t work.”
The scientific team is a patchwork from Italy, Germany, Greece and the United Kingdom. They modeled their robot on a polychaetes or paddle worm, a creature that looks like a tiny crew boat with a half dozen paddles sticking out on each side. So far the team has tested the device in a section of pig gut. The results were sufficiently encouraging, and now the next step is to incorporate a camera and light source.
Andrew Gardner, an independent medical imaging expert at the University College, London, gave guarded remarks about the prototype robot (which people would swallow like a pill) in his comment to the New Scientist. “Capsules can show you places nothing else can, but you can’t stop or slow down when you get to a point of interest,” he said. “Being able to have some control, perhaps even to turn around and go to look in a crevice that would otherwise be missed.”
Gardner also pointed out that mishaps could be many in the lengthy environment of the GI tract. “If something this complicated goes wrong, it could be very hard to get out.”
Thus the reason for continued testing – years of it under the direction of the best and brightest in the labs and on animals before scientists will consider it prudent to let one of the robots use its delicate flagella to worm its way through a human GI tract.
Until then, it appears we’re stuck with the traditional tests, and tiny robots making their way through the inner recesses of the body will remain the stuff of science fiction. At least it’s something to ponder the next time we find ourselves on the receiving end of the endoscope.
