Researchers at the Massachusetts General Hospital in Boston have developed a tethered, pill-sized endoscope that provides cross-sectional and three-dimensional microstructural images of the upper gastrointestinal tract. The procedure requires minimal training, does not need anesthesia and is pain-free. The patient swallows the clear plastic pill with a cup of water, after which it can be moved up and down the esophagus to capture images using the attached wire.
The device works via optical frequency domain imaging, using a beam of infrared light which is split into two with mirrors. One beam is used as a reference; the other is sent through the tether, into the pill, where it is directed into the tissue. The beam spins around the pill’s axis 20 times per second and the signal of the reflected light is compared to the reference signal to reconstruct a cross-sectional image. Subsequent stacking of these images results in a three-dimensional image of the esophagus.
Images are captured at a 30 μm (lateral) × 7 μm (axial) resolution. Not only the surface is imaged, but also underlying tissue up to a depth of around 10 microns, providing information about abnormal growth patterns as a potential precursor to cancer. The research was published in Nature Medicine.
Here’s a short video report from Nature Medicine about the technology:
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