At the new endoscope’s glass fiber tip, light refracts into a rainbow of colors that reflect off tissue (shown above). The fiber’s tip is just 350 micrometers wide. Credit: Courtesy of the Wellman Center for Photomedicine, Massachusetts General Hospital

In an endoscope meant to penetrate the brain, look at a fetus, or thread through tiny ducts, smaller is better. But the endoscopes that produce the clearest 3-D images use cameras several millimeters wide--too big to go many places in the body. Now researchers at Massachusetts General Hospital in Boston have demonstrated an endoscope that's just 350 micro­meters wide and sends back 3‑D images that are as clear as those produced by larger endoscopes.

Select from the choices above to read the entire article.