A Confocal Endoscope for Cellular Imaging

Jiafu Wang; Min Yang; Li Yang; Yun Zhang; Jing Yuan; Qian Liu; Xiaohua Hou; Ling Fu

doi:10.15302/J-ENG-2015081

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Engineering ›› 2015, Vol. 1 ›› Issue (3) : 351-360. DOI: 10.15302/J-ENG-2015081

Research

A Confocal Endoscope for Cellular Imaging

Jiafu Wang¹^,² ,
Min Yang³ ,
Li Yang¹^,² ,
Yun Zhang¹^,² ,
Jing Yuan¹^,² ,
Qian Liu¹^,² ,
Xiaohua Hou³ ,
Ling Fu¹^,²

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Abstract

Since its inception, endoscopy has aimed to establish an immediate diagnosis that is virtually consistent with a histologic diagnosis. In the past decade, confocal laser scanning microscopy has been brought into endoscopy, thus enabling in vivo microscopic tissue visualization with a magnification and resolution comparable to that obtained with the ex vivo microscopy of histological specimens. The major challenge in the development of instrumentation lies in the miniaturization of a fiber-optic probe for microscopic imaging with micron-scale resolution. Here, we present the design and construction of a confocal endoscope based on a fiber bundle with 1.4-μm lateral resolution and 8-frames per second (fps) imaging speed. The fiber-optic probe has a diameter of 2.6 mm that is compatible with the biopsy channel of a conventional endoscope. The prototype of a confocal endoscope has been used to observe epithelial cells of the gastrointestinal tracts of mice and will be further demonstrated in clinical trials. In addition, the confocal endoscope can be used for translational studies of epithelial function in order to monitor how molecules work and how cells interact in their natural environment.

Keywords

cellular resolution / confocal endoscopy / optical biopsy

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Jiafu Wang, Min Yang, Li Yang, Yun Zhang, Jing Yuan, Qian Liu, Xiaohua Hou, Ling Fu. A Confocal Endoscope for Cellular Imaging. Engineering, 2015, 1(3): 351‒360 https://doi.org/10.15302/J-ENG-2015081

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Acknowledgements

The authors thank Hui Li, Nian Tian, Zhou Zhou, and Geng Tian for image analysis and Ying Wang for providing information related to the fiber scanning devices. The authors also greatly appreciate Xiu Nie from the Department of Pathology of Union Hospital at Huazhong University of Science and Technology for help with the histologic specimen. This work was supported by the National Key Technology R&D Program of China (2011BAI12B06), and National Natural Science Foundation of China (61205197 and 61178077).

Compliance with ethics guidelines

Jiafu Wang, Min Yang, Li Yang, Yun Zhang, Jing Yuan, Qian Liu, Xiaohua Hou, and Ling Fu declare that they have no conflict of interest or financial conflicts to disclose.

Funding