Summary

FiberTech Co., Ltd. (head office: Chiyoda-ku, Tokyo, President: Shinya Miike, hereinafter “FiberTech”) has announced that it has developed a real-time confocal endoscope system in collaboration with Hamamatsu University School of Medicine (hereinafter “HUSM”) and Yokogawa Electric Corporation (hereinafter “Yokogawa”) as one of the projects of the Hamamatsu Region Intellectual Cluster Construction Program promoted by Organization for Hamamatsu Technopolis. This system has been co-developed with Professor Dr. Susumu Terakawa and Research Associate Dr. Takashi Sakurai, Photon Medical Research Center, HUSM, by integrating the technology of confocal scanner CSU owned by Yokogawa and the ultra-thin fiberscope technology owned by FiberTech. It is a revolutionary imaging system that allows monitoring of cellular activity.


Background

Cellular activity in deep brain or organs have been mostly unknown because it has been difficult to visualize in vivo fluorescence image of such deep cells with the conventional endoscope and microscope. Although researchers have tried various methodologies, it has been impossible to reveal the activity of cells as small as 20 microns unless by optical magnification at a microscopic level. Objective lens of the conventional microscope cannot be introduced deep into the body, and magnification level of the conventional endoscope is not sufficient. To solve these issues, the development of a confocal endoscope was initiated by integrating the technologies of confocal microscope and FiberTech’s ultra-thin fiberscope. If the development proves successful, this new technology may significantly advance life science studies and may usefully be applied to various fields such as vital sign analysis, drug discovery, clinical examination, and cancer treatment.

(e.g.)
1. Long-term serial follow-up of brain function and stem cells, and analysis of mechanism of disease
2. Drug discovery support through long-term monitoring of effect of drug on organs
3. Early detection of cancer through real-time examination of the digestive system
4. Photodynamic therapy (PDT) for cancer


Development Results

The developed endoscope has shown sufficient results: it offers spatial resolution (measured by fluorescent bead array) of 1 micron in the image plane (X, Y) and 5 micron along the optical axis (Z), and scan rate is 30 flames per second. There is room to slightly improve spatial resolution by ameliorating the light guide and to increase temporal resolution up to 250 flames per second by improving light use efficiency. This endoscope employs Nipkow disc with a micro lens, and multi-fibers for the working probe. Its fiber bundle binds 10,000 pieces of optical fibers (each fiber is 3.75 micron in diameter) and each end of the fiber is designed to optically conjugate to the pinhole of the confocal system. The endoscope is as thin as 0.75mm in outside diameter and has the shape minimally invasive for in vivo use.