There is a critical clinical need for a noninvasive high-resolution imaging technology for early cancer detection and guidance of biopsy in internal organs. Two-photon fluorescence (TPF) and second harmonic generation (SHG) microscopy is a powerful technology to address the above clinical need by providing structural and biochemical/metabolic information about biological tissues at subcellular resolution without the need for tissue removal or external fluorescent agents. However, its in vivo clinical application remains extremely limited due to the lack of a miniature technology platform. The objective of this multidisciplinary proposal is to develop an all-fiber-optic scanning endomicroscopy technology which is able to bring TPF/SHG microscopy to clinic for internal organ imaging. It involves 5 partners with 2 from academia and 3 from industry. The proposed technology will integrate all essential functions of a scanning laser microscope into a single flexible fiber-optic probe of a small diameter (~2.4-3.4 mm), with built-in mechanisms for femtosecond pulse delivery, dispersion management, nonlinear effect suppression, beam focusing, rapid 2D raster beam scanning, TPF/SHG collection, and focus tracking (or depth scanning). The small size permits its integration with a standard red-flagging technology (such as a gastroscope). In this proposal, we plan to tackle the major challenges in developing such an endomicroscopy technology and evaluate its feasibility for subcellular resolution imaging and for cancer detection.
The Specific Aims are to: (1) Develop new double-clad fibers (DCF) of a pure silica core, large inner clad and numerical aperture to dramatically suppress the in-fiber TPF/SHG background (e.g. by 50 folds) and improve TPF/SHG collection efficiency (e.g. by ~15 folds) over commercially available DCFs;(2) Develop a super-achromatic microlens of a 2.1mm diameter and 0.6 NA to improve the TPF/SHG collection efficiency by at least 20 folds over a GRIN lens;(3) Explore a novel approach based on high-order mode DCFs to suppress nonlinear effects in optic fiber and improve TPF/SHG excitation probability;(4) Develop novel MEMS scanners of a small footprint (1.6 x 1.6 mm) and an extremely low drive voltage (10V max) to achieve rapid 2D raster beam scanning and real-time focus tracking. A fully integrated endomicroscope with customized DCFs, microlens and MEMS scanners will be developed, capable of 3D TPF/SHG imaging;(5) Conduct in vivo endoscopic TPF/SHG imaging of swine esophagus to evaluate the performance, and design, engineering and operation issues of the scanning probe;and (6) Evaluate the feasibility of the proposed technology for cancer detection and tumor margin identification using ex vivo human esophagus specimens, and correlate TPF/SHG endomicroscopy images with corresponding histology. The significance of the proposed research is to translate the powerful TPF/SHG microscopy technology to clinical practice for cancer detection and image-guided biopsy in internal organs, and enable noninvasive real-time visualization of tissue histopathology in situ to significantly improve diagnostic and biopsy yields. In addition, the proposed endomicroscopy technology will also be applicable (although outside the scope of this proposal) to many other clinical scenarios such as for guidance of surgical interventions and for in vivo assessment of metabolic function of living tissues.
The objective of this multidisciplinary proposal is to develop and test an all-fiber-optic 3D scanning endomicroscopy technology, which can bring the powerful bench-top TPF/SHG microscopy technology to clinical practice for imaging internal organs (such as the gastrointestinal tract) that was not previously possible with TPF/SHG microscopy. The proposed technology can function in a form of """"""""optical biopsy"""""""" by providing structural and biochemical/metabolic information about biological tissues at subcellular resolution without the need for tissue removal or external fluorescent agents. Successful completion of the proposed research will bring us a new tool, which enables visualization of histopathology in situ and improves our capability for early cancer detection, tumor margin identification, and guidance of biopsy and interventions.
|Yuan, Wu; Mavadia-Shukla, Jessica; Xi, Jiefeng et al. (2016) Optimal operational conditions for supercontinuum-based ultrahigh-resolution endoscopic OCT imaging. Opt Lett 41:250-3|
|Yan, Lesan; Li, Xingde (2016) Biodegradable Stimuli-Responsive Polymeric Micelles for Treatment of Malignancy. Curr Pharm Biotechnol 17:227-36|
|Zhang, Xiaoyang; Duan, Can; Liu, Lin et al. (2015) A non-resonant fiber scanner based on an electrothermally-actuated MEMS stage. Sens Actuators A Phys 233:239-245|
|Liu, Lin; Wang, Erkang; Zhang, Xiaoyang et al. (2014) MEMS-BASED 3D CONFOCAL SCANNING MICROENDOSCOPE USING MEMS SCANNERS FOR BOTH LATERAL AND AXIAL SCAN. Sens Actuators A Phys 215:89-95|
|Xi, Jiefeng; Zhang, Anqi; Liu, Zhenyu et al. (2014) Diffractive catheter for ultrahigh-resolution spectral-domain volumetric OCT imaging. Opt Lett 39:2016-9|
|Zhang, Anqi; Xi, Jiefeng; Liang, Wenxuan et al. (2014) Generic pixel-wise speckle detection in Fourier-domain optical coherence tomography images. Opt Lett 39:4392-5|
|Chen, Yongping; Zhang, Yuying; Liang, Wenxuan et al. (2012) Gold nanocages as contrast agents for two-photon luminescence endomicroscopy imaging. Nanomedicine 8:1267-70|
|Xi, Jiefeng; Chen, Yongping; Zhang, Yuying et al. (2012) Integrated multimodal endomicroscopy platform for simultaneous en face optical coherence and two-photon fluorescence imaging. Opt Lett 37:362-4|
|Zhang, Yuying; Akins, Meredith L; Murari, Kartikeya et al. (2012) A compact fiber-optic SHG scanning endomicroscope and its application to visualize cervical remodeling during pregnancy. Proc Natl Acad Sci U S A 109:12878-83|
|Liang, Wenxuan; Murari, Kartikeya; Zhang, Yuying et al. (2012) Increased illumination uniformity and reduced photodamage offered by the Lissajous scanning in fiber-optic two-photon endomicroscopy. J Biomed Opt 17:021108|
Showing the most recent 10 out of 13 publications