High-Resolution, Wide-Field, Forward-Viewing Spectrally Encoded Endoscope

Lasers Surg Med. 2019 Nov;51(9):808-814. doi: 10.1002/lsm.23102. Epub 2019 May 26.

Abstract

Background and objective: Spectrally encoded endoscopy (SEE) is an optical imaging technology that uses spatial wavelength multiplexing to conduct endoscopy in miniature, small diameter probes. Contrary to the previous side-viewing SEE devices, forward-viewing SEE probes are advantageous as they provide a look ahead that facilitates navigation and surveillance. The objective of this work was to develop a miniature forward-viewing SEE probe with a wide field of view and a high spatial resolution.

Materials and methods: We designed and developed a forward-viewing SEE device with an overall total diameter of 1.27 mm, which consists of a monolithic illumination probe with a length of 3.87 mm and a diameter of 500 µm, 8 multimode detection fibers that were polished at a 17° angle, a rotational scanning mechanism, and a sheath. The SEE device was evaluated using a USAF resolution target and was used for preclinical imaging of a swine joint ex vivo.

Results: This design resulted in a high resolution probe (best spatial resolution of 20.3 µm), a wide total angular field of view of 100°, and an effective number of imaging elements of ~344,000 pixels. The SEE probe performance was compared to a commercial color chip-on-the-tip endoscope; while monochrome, results showed better spatial resolution and a wider field of view for the SEE device.

Conclusion: These results demonstrate the potential of this forward-viewing SEE probe for visualization and navigation in medical imaging applications. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Keywords: forward-viewing; miniature endoscopy; spectrally encoded endoscopy; wide-field.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Endoscopes*
  • Equipment Design
  • Joints / anatomy & histology
  • Optical Phenomena
  • Swine