Scientists have managed to developed a camera that can see through the human body.
The device has been designed to be used by doctors during internal examinations in order to track medical tools, known as endoscopes.
Until now, medics have had to rely on expensive scans, such as X-rays, to trace their progress.
The new camera works by detecting light sources inside the body, such as the illuminated tip of the endoscope's long flexible tube.
"The ability to see a device's location is crucial for many applications in healthcare, as we move forwards with minimally invasive approaches to treating disease" Prof Kev Dhaliwal, of the University of Edinburgh, said.
Early tests have shown the prototype device can track a point light source through 20 cm of tissue under normal conditions.
The new camera can detect individual particles, called photons, and is so sensitive it can catch tiny traces of light passing through tissue.
It can also record the time taken for light to pass through the body, meaning the device is able to work out exactly where the endoscope is.
Researchers have developed the new camera so it can be used at the patient's bedside.
Read more at BBC.