Boffins in Germany were chuffed indeed yesterday, as they announced successful trials of the latest medi-tech development: swallowable, remote controlled video-cam "capsule" submarines, able to probe a patient's guts without the need for an intrusive umbilical cable running down the throat or up the bottom.
Thus far, docs needing a good look at the inside of someone's stomach, intestines etc have employed two methods: the mainstream one involves use of a conventional endoscope, in effect a flexible tentacle periscope inserted at one end of the alimentary canal or the other.
Naturally enough this tactic causes a certain amount of disquiet among patients (as the researchers put it, "some view endoscopy as uncomfortable, and worry about low patient compliance").
One possible technique is the use of swallowed, battery-powered capsule cameras, transmitting their imagery wirelessly. The trouble with this is that simply allowing the point of view to be dictated by the action of the patient's guts makes it hard to tell what's being filmed or where, and in general the medics have no real idea what coverage has been achieved, especially in the comparatively large arena of the stomach. ("Capsule endoscopies have shown that visualization of the stomach is highly variable".)
Similarly, wireless cam-probes have also been developed for deployment at the other end of the digestive system, but these have perhaps understandably achieved less, erm, takeup. ("A wireless colon capsule for visualizing the colon for screening purposes has been developed, but is not currently FDA approved").
This situation made Doktor Jutta Kella of the Hamburg uni internal-medicine department and her colleagues mad, and they decided to do something about it. Enter the steerable, manoeuvrable, miniature unmanned stomach-submarine.
“To address the problems with a conventional capsule endoscope in visualizing the stomach, a new tool for maneuvering the capsule using an external handheld magnet was developed, allowing targeted investigation of all regions of the stomach,” says Kella.
The magno-directed wireless stomach submarine was apparently assembled by taking a standard colon-intruder unit and adding magnetic discs to create a dirigible tum-prowler capsule. This was tried out on 10 healthy volunteers in Hamburg. In order to get their stomachs to unfurl for easier viewing they swallowed sherbet powder along with the magnetised belly probes, causing the normally partially-collapsed, wrinkly digestive sacs to inflate like balloons.
According to Kella and her colleagues, their kit was capable of outloading pictures at four frames per second, providing real-time imagery from inside the test subjects' bodies.
“The aim of our study was to evaluate the safety and feasibility of the magnetic maneuvering of a capsule endoscope in a human stomach. We found that the magnetic maneuvering of the capsule was safe and very well-tolerated, with excellent responsiveness of the capsule to movements of the outer magnet so that detailed visualization of the gastric mucosa could be achieved," says the good Doktor.
Full details of the experiments are disclosed in Kella and her colleagues' scholarly report, published here by the journal Gastrointestinal Endoscopy (subscription link). ®