In pursuit of less-invasive diagnostics, researchers from George Washington State University have developed a swallowable, magnetically controlled pill, promising a high-resolution feed of the stomach. The “pill cam” can help doctors record video and photograph any possible bleeding, inflammatory or malignant lesions with a 95% rate of visualisation.
With an external magnet and hand-held videogame style controls (two joysticks), researchers tested a magnetically controlled capsule endoscopy in 40 individuals. The new method missed no high-risk lesions compared to an endoscopy, and 80% of those who received it preferred it to a traditional endoscopy.
“This trial is significant because it is the first US study to show the feasibility and potential utility of using MCCE to visualize the entire stomach,” the researchers write in the study published in iGIE, the official journal of the American Society for Gastrointestinal Endoscopy.
With promising results in this pilot study, magnetically controlled capsule endoscopy (MCCE) could pose as a viable alternative to endoscopies.
Diagnosing with discomfort
Endoscopies allow doctors to directly visualize internal organs, providing a clear view of issues inside the body and sometimes even allowing for action to be taken in situ. However, for those undergoing the procedure, it can be highly uncomfortable.
Depending on the type of endoscopy, a flexible tube with a camera inside is inserted into the mouth, anus, vagina or urethra. In a typical gastroscopy, the tube is inserted into the mouth and passed down through the throat and into the stomach. One’s gag reflex is invariably triggered, which is why those who must undergo this procedure are asked not to eat anything for at least six hours before the test. The procedure itself can be done with sedation, negating some of the discomfort.
Though useful, endoscopies present with limitations. Those in unstable medical condition may need to be stabilized before the procedure can be done — a potentially costly delay. As a result, the hunt for an alternative to the endoscopy has been ongoing for decades.
A tiny video capsule
Most promising has been the advent of capsule endoscopy — where one has but to swallow a pill with a small camera inside it. Once the capsule is inside the oesophagus, peristalsis carries it to the stomach. The high-resolution feed provided by the camera allows diagnosticians to spot early signs of cancer, internal distress or other markers of disease.
While the procedure is proving popular among those who refuse endoscopy, it too has limitations. Only gravity and the body’s own system of internal movement (peristalsis) could be used to direct these pills, limiting diagnosticians’ ability to analyse areas of interest inside the body.
But instead of moving a camera with a wire, what if one simply used a magnet? Magnetically controlled capsule endoscopy (MCCE) could allow doctors to “purposefully direct the capsule to regions of interest in the stomach”, according to the study.
Significantly, the advancement could be useful for those for whom a regular endoscopy could be inadvisable. These include those who have epigastric pain, bloating, burning, heartburn, excessive belching, nausea and/or vomiting, anaemia, or weight loss.
After swallowing, the capsule takes just ten seconds to reach the stomach. A physician with no prior specialty training in endoscopy was selected as the operator, after going through a previously designed capsule training curriculum. Learning from a plastic model of the stomach, the operator was able to get familiar with the software and the two-joystick controllers.
Like a video game
While one joystick controlled the translational movement of the capsule in the x-y-z axes, the other controlled rotation along horizontal or vertical axes. The similarity to video game controls making the device extremely intuitive to control for healthcare professionals.
With the study is still in the pilot phase, a larger trial is needed to test its safety and efficacy. One limitation of the method is that unlike with an endoscopy, the capsule cannot take action directly when lesions are spotted. A follow-up procedure will need to be performed for this.
“MCCE may provide a safe and efficient way to screen low-risk patients for serious disease such as gastric cancer. EGD screening is currently recommended in Japan and Korea but not in the United States and Western Europe because of the very low prevalence of early gastric cancer,” the study added.
