Comparable in thickness to a human hair, the optical probe has a tiny lens, which provides unprecedented access to 3D scanning inside blood vessels and other hard-to-reach places in the human body.
An Australian-German team has developed the smallest human hair-thin imaging device in the world. It is able to navigate through the blood vessels of mice, offering unparalleled 3D body scanning capabilities at microscopic resolution.
To create this miniature endoscope, the team took a thin optical fiber less than half a millimeter in diameter, including its protective sheath. The researchers then used a 3D microprinting technique to print into it a tiny lens with a side diameter of less than 0.13 mm — too small to be seen with the naked eye.
This optical fiber was then connected to an optical coherence tomography (OCT) scanner as a flexible probe. OCT is a 3D sensitive depth scanning technology commonly used for retinal mapping in optometry and ophthalmology. It uses near-infrared light to penetrate tissue, measuring wave interference between the reference beam and probe beam to create 3D images that allow tissue to be viewed at microscopic resolution.
Using this technology, the team created an OCT scanning device small enough to pass through blood vessels in the body. This ultra-thin probe can be rotated and slowly pulled back to build a 3D map of the environment to about half a millimeter below the surface. The probe offers unprecedented ability to scan the body’s vascular system for plaques made from fat, cholesterol and other substances that tend to build up in blood vessel walls and lead to heart disease.
The team has successfully tested the device in both human and mouse blood vessels, demonstrating its ability to deliver high-quality OCT images and reach hard-to-reach areas. The clear lens allows the scanner to create an image depth five times deeper than previous counterparts. The researchers believe this tiny probe could open up new possibilities for scanning hard-to-reach places like the cochlea and parts of the nervous system. The team included medical doctors and engineers from the University of Adelaide and the University of Stuttgart.