In Vivo Rat Brain Imaging through Full-Field Optical Coherence Microscopy Using an Ultrathin Short Multimode Fiber Probe

Manabu Sato,Reiko Kurotani,Izumi Nishidate,Kai Eto,Hiroyuki Abe,Kenji Inoue,Junpei Masuta

doi:10.3390/app9020216

Abstract

We demonstrate full-field optical coherence microscopy (OCM) using an ultrathin forward-imaging short multimode fiber (SMMF) probe with a core diameter of 50 μm, outer diameter of 125 μm, and length of 7.4 mm, which is a typical graded-index multimode fiber used for optical communications. The axial and lateral resolutions were measured to be 2.14 μm and 2.3 μm, respectively. By inserting the SMMF 4 mm into the cortex of an in vivo rat brain, scanning was performed to a depth of 147 μm from the SMMF facet with a field of view of 47 μm. Three-dimensional (3D) OCM images were obtained at depths ranging from approximately 20 μm to 90 μm. Based on the morphological information of the resliced 3D images and the dependence of the integration of the OCM image signal on the insertion length, the obtained 3D information of nerve fibers has been presented.

Highlights

Optical coherence tomography (OCT) has become a mainstay in biomedical imaging technology owing to its noninvasive imaging and higher spatial resolution, and has been one of the most rapidly developed optical imaging modalities of the last few decades
We have reported the images obtained by FF-optical coherence microscopy (OCM) with short multimode fiber (SMMF) of a diameter of 125 μm and a length of 7.4 mm using ex vivo rat brains [30]
We have previously studied the relations among linearly polarized (LP) modes, depolarizations, and imaging in SMMF [28]

Summary

Introduction

Optical coherence tomography (OCT) has become a mainstay in biomedical imaging technology owing to its noninvasive imaging and higher spatial resolution, and has been one of the most rapidly developed optical imaging modalities of the last few decades. The most developed domain is ophthalmology, and its ability to differentiate between layers of the retina has made it a standard diagnostic tool [1,2,3]. Various probes have been developed for OCT to extend the range of its applications [4,5]. Robust, and reliable endoscopic probes and imaging catheters have long been in demand in various fields of biomedical optics. The size of the imaging probe is important in achieving minimally invasive accessibility to deep regions. Most probe implementations can be divided into two groups based on their scan modes: Side-imaging or forward-imaging

Results

Discussion

Conclusion