Ultrathin monolithic 3D printed optical coherence tomography endoscopy for preclinical and clinical use

Jiawen Li,Rodney W Kirk,Harald Giessen,Robert A Mclaughlin,Emma Akers,Simon Thiele,Stephen J Nicholls,Alois M Herkommer,Johan W Verjans,Bryden C Quirk,Christina A Bursill

doi:10.1038/s41377-020-00365-w

Abstract

Preclinical and clinical diagnostics increasingly rely on techniques to visualize internal organs at high resolution via endoscopes. Miniaturized endoscopic probes are necessary for imaging small luminal or delicate organs without causing trauma to tissue. However, current fabrication methods limit the imaging performance of highly miniaturized probes, restricting their widespread application. To overcome this limitation, we developed a novel ultrathin probe fabrication technique that utilizes 3D microprinting to reliably create side-facing freeform micro-optics (<130 µm diameter) on single-mode fibers. Using this technique, we built a fully functional ultrathin aberration-corrected optical coherence tomography probe. This is the smallest freeform 3D imaging probe yet reported, with a diameter of 0.457 mm, including the catheter sheath. We demonstrated image quality and mechanical flexibility by imaging atherosclerotic human and mouse arteries. The ability to provide microstructural information with the smallest optical coherence tomography catheter opens a gateway for novel minimally invasive applications in disease.

Highlights

Fiber-optic endoscopes have become an indispensable clinical tool, providing diagnostic images of the internal lumen of hollow organs and real-time guidance during interventions[1,2,3,4]
The beam shaping micro-optic was directly 3D printed onto the distal end of the no-core fiber using a two-photon lithography system (Photonic Professional GT, Nanoscribe, Germany) that was modified with a fiber holder directly attached to the system[30]
In this work, we developed a monolithic, ultrathin highresolution endoscopic optical coherence tomography (OCT) probe by directly writing freeform micro-optics onto a single-mode fiber terminated with no-core fiber

Summary

Introduction

Fiber-optic endoscopes have become an indispensable clinical tool, providing diagnostic images of the internal lumen of hollow organs and real-time guidance during interventions[1,2,3,4]. OCT has become a widely used tool for assessments in preclinical animal models[6,7] Despite these advances, there remains a practical but unmet need for miniaturized high-resolution probes that enable the imaging of delicate narrow luminal organs and small animals and prevent the potentially. The small scale of the optics makes it very challenging to correct for spherical aberration, which can further degrade the resolution and depth of focus[10]. The correction of the spherical aberration of a single lens is only possible by using an aspherical lens profile (described by a polynomial instead of a circle equation). This shape, is difficult to realize on a fiber tip where lenses are often made using a melting process (e.g., creating a spherical ball lens with a profile described by a circle equation)

Methods

Results

Conclusion