Smallest 3D printed miniature endoscope in the world

Dr. Simon Thiele from the group of Prof. Alois Herkommer at the Institute of Technical Optics at University of Stuttgart teamed up with 3D printing experts of the group of Prof. Harald Giessen in Stuttgart and developed together with fiber OCT experts Dr. Jiawen Li and Prof. Robert McLaughlin from University of Adelaide the smallest endoscope of the world, with an outer diameter including the sheath of less than 0.5 mm. Together with colleagues from Royal Adelaide Hospital, SAHMRI Institute in Adelaide and Monash Cardiovascular Research Center in Melbourne, they used the 3D printed microoptical OCT endoscope to examine the inside of blood vessels of mice and humans. The doctors obtained highly accurate 3-dimensional images of the veins, which were later compared with histological stained images.

The 3D printed microoptics focused to laser beam from the fiber to a fine spot, correcting also for the aberrations in the cylindrical plastic sheath. The OCT system was able to detect plaques as well as cholesterol crystals in human carotid arteries as well as in aortas of obese mice. These causes for vascular deseases could be well detected by the fiber endoscope, which rotated like a spiral inside the blood vessels. Comparisons with stained microscope images of the sliced tissue confirmed the early detection by OCT.

Dr. Simon Thiele, who designed the miniature optics, believes that the new system could add significantly to the already 400 000 performed OCT endoscopic examinations. Millions more could be performed inside blood veins and detect early plaques and cholesterol crystals. He believes that one might be able to dissolve such plaques in the future with a suited laser beam using such a miniature endoscope, which can easily enter such small vessels.