Reflectance confocal endomicroscope with optical axial scanning for in vivo imaging of the oral mucosa.

Joey M Jabbour,Julie L Bentley,Kristen C Maitland,John Nemechek,Rodrigo Cuenca,Javier A Jo,Shuna Cheng,John Warda,Bilal H Malik

doi:10.1364/boe.5.003781

Abstract

This paper presents the design and evaluation of a reflectance confocal laser endomicroscope using a miniature objective lens within a rigid probe in conjunction with an electrically tunable lens for axial scanning. The miniature lens was characterized alone as well as in the endoscope across a 200 µm axial scan range using the tunable lens. The ability of the confocal endoscope to probe the human oral cavity is demonstrated by imaging of the oral mucosa in vivo. The results indicate that reflectance confocal endomicroscopy has the potential to be used in a clinical setting and guide diagnostic evaluation of biological tissue.

Highlights

The utility of reflectance confocal microscopy (RCM) is underscored by its ability to provide high fidelity, label-free cross-sectional images of biological tissue at sub-cellular resolution [1, 2]
Multiple lens objectives can offer high numerical aperture (NA) while minimizing aberrations, all at diameters of a few millimeters. Such microscope objectives have been used in reflectance confocal laser endomicroscopy (rCLE) systems [6, 7], as well as other high resolution imaging modalities such as non-linear microscopy [8, 9]
In our continuing effort towards development of a compact and mobile rCLE system, we present a rigid handheld endomicroscope which addresses the two aforementioned limitations currently preventing the realization of practical rCLE systems

Summary

Introduction

The utility of reflectance confocal microscopy (RCM) is underscored by its ability to provide high fidelity, label-free cross-sectional images of biological tissue at sub-cellular resolution [1, 2]. In vivo applications of RCM have been somewhat limited, mainly due to the constraints put forth by the bulk of optics, in high resolution systems Toward this end, miniaturization of the microscope objective is arguably the most important step in realization of practical, compact and mobile reflectance confocal laser endomicroscopy (rCLE) systems. Miniaturization of the microscope objective is arguably the most important step in realization of practical, compact and mobile reflectance confocal laser endomicroscopy (rCLE) systems Development in this area has mainly been in two categories: multiple-lens objectives and probes based on graded-index (GRIN) lenses. Most realizations of axial scanning require moving the sample or the objective lens relative to each other, typically adding to the bulk of optics, and limiting the compactness and usability of the imaging system in vivo [15, 16]. The outer housing of the rCLE is made out of Delrin plastic, which is known for its robustness and light weight

Miniature lens design

Conclusion