Time：11:20-11:40 Dec. 21
In-vivo Imaging Using Miniaturized Microscope
Assis. Prof. Zhen Qiu
Michigan State University, USA
Zhen Qiu is an Assistant Professor in the Department of Biomedical Engineering, Institute for Quanti- tative Health Science and Engineering, Michigan State University, MI. He received the Ph.D. degree from the Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI. He finished his post-doctoral training in the Department of Radiology and Molecular Imaging Program Stanford (MIPS), School of Medicine, Stanford University, CA. His current research interests include biomedical optics, MEMS/MOEMS, multi-modal targeted imaging using novel contrast agents, wearable and implantable medical devices, ultrafast laser applications. He aims to study both cancer biology and translational medicine with custom-made micro-systems enabled ultra-thin in-vivo sensing/imaging tools. His work is mainly focused on miniaturized optical imaging system development for early cancer detection and imaging guided surgical navigation, such as wide-field imaging guided micro-scanner based confocal microendoscope, multi-photon/SHG handheld microscope, and SERS nanoparticles based Raman spectroscopy.
MEMS based microendoscopes have become important imaging tools for early cancer diagnosis and precise tumor resection. Due to various technical challenges, few microendoscopes have been translat- ed to clinics or applied to human patients. Through synergistic collaborations, we have developed novel MEMS scanner enabled microendoscopic multispectral (640nm to 780nm) three- dimensional dual-axis confocal fluorescent imaging system for translational applications, including early cancer detection and staging on colorectal cancer, molecular imaging guided surgical navigation on head and neck cancer. Based on dual-axis confocal microscopic architecture, we have miniaturized the imaging system with compact form-factor by integrating micro-optics and a patterned gold coated MEMS scanners, which have been custom-made and mass-produced in the nanofabrication foundry. The metal coating of the scanning mirror provides over 80% high reflectivity over near infra-red range. Both axes of the MEMS scanner could perform large tilting angle (> 6 degree mechanical scan angle) at DC and resonant mode. By advanced computational imaging approach, we have achieved real-time cross-sectional imaging in either raster or lissajous pattern scanning with fast frame rate (> 10 Hz) with large field-of-view (> 600 microns). Advanced real-time mosaicing algorithm has been developed to achieve broader view in milli- meter scale. By utilizing molecular contrast probes conjugated with fluorescence dye, we have success- fully demonstrated multi-spectral ex-vivo and in-vivo imaging on small animal tumor models and human tissue specimens, aimed for both early cancer detection and molecular imaging guided surgical naviga- tion.