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Laboratory of
Ocular Biomechanics

University of Pittsburgh

Po-Yi Lee

    Po-Yi Lee

    University of Pittsburgh
    Ph.D., Biomedical Engineering

    Pittsburgh, PA
    present

    National Taiwan University
    M.S., Biomedical Electronics and Bioinformatics

    Taipei, Taiwan
    2016

    National Tsing Hua University
    B.S., Biomedical Engineering and Environmental Sciences & Electrical Engineering (double major)

    Hsinchu, Taiwan
    2014


    I am a PhD student with training and interest in biomedical imaging and image analysis. My research devotes to developing new or advancing existing imaging techniques for use in biomedicine. I have worked on research projects spanning optical imaging, bioimage informatics, and photoacoustics. My current research focuses on developing polarized light microscopy to visualize and qunatify collage fiber architecture with mechanical testing.


 

Optical Imaging for Ophthalmic Applications

    I am working on my PhD in the Laboratory of Ocular Biomechanics under supervision of Ian A. Sigal, PhD. My research includes polarized light microscopy, optical coherence tomography, and mechanical testing.


    Instant polarized Light Microscopy: Colorization of Collagen Fiber Orientation without Image Processing


    The research was to advance a new polarized light microscopy technique which can colorize collagen fiber orientation without image processing. That is, single image "the snapshot", allows visualizing the collagen fiber orientation. Since it only requires one image, it can be done in real time, and is therefore a powerful tool for dynamic mechanical testing. In addition, I have done simulations to study the relationship between colors and fiber properties such as orientation and retardance. Therefore, the colorful images can be quantified into angles based on the simulated result. I work closely with Bin Yang, PhD. The work was presented at the Carnegie Mellon Forum on Biomedical Engineering and was awarded 1st prize in the imaging category.


 

Cell Image Processing and Analysis for Lattice Light Sheet Microscopy

    Before starting my PhD work, I was a research assistant in Academia Sinica in 2017-2018 under the supervision of Bi-Chang Chen, PhD, focusing on cell image processing and analysis for lattice light-sheet microscopy. Segmentation is the prerequisite for image analysis, such as quantification and tracking, whereas it has to overcome photobleaching, aberration, and heterogeneous environments.


    Visualization and Quantification of Mitochondrial Dynamics during Mitosis


    This work focused on image segmentation, analysis, and visualization for mitochondria dynamics, which was observed through over thousands of volumes within 20 mins to span cell division process by lattice light-sheet microscopy. Segmentation and graphing provide the access to quantify mitochondrial distribution, motion, and fission-fusion dynamics. In this study, the findings imply that both mitochondrial redistribution and the fission-fusion frequency are related to mitotic phases and that mitochondrial segregation may be triggered by the form of cleavage furrows.


    Nanoparticle tracking for Cytoskeletal Dynamics


    This work was a demonstration to understand how cytoskeletal changes in the cell by nanoparticles. The nanoparticles on the cytoskeleton were detected by wavelet filters and was tracked by Jaqaman's algorithm which was implemented by Amira. Since cytoskeleton can be viewed as simply a structural framework playing a role in cell shape and motile events, the footprint of nanoparitcles are can be a marker in cell processes.


    Chromosome Tracking


    The work focused on tracking chromosomes of C. Elegant embryo, where the chromosomes were detected and converted into lines for endpoint tracking. The method provided an access to understand what the arrangement of chromosomes during cell division in the early stage.




    Segmentation of Epithelial Phenotype


    This work was to visualize and quantify the regions of Drosophila Embryo by Cadherin, an epithelial marker. It is a way to understand the epithelial-mesenchymal transition.






    Embryonic Lineage Tracing of C. Elegans


    This work was to trace the embryonic lineage of C. Elegant. Segmentation was based on watershed transformation; tracing was based on overlapped regions over time. The analysis provided an access to understand the timing of cell proliferation and the corresponding volumes and positions.


    Visualization of Membrane Ruffling


    This works was to segment the membrane over time. The segmentation was based on histogram analysis to compensate photobleaching so that the segments were reliable over time. The results provided an access to quantify the change of volumes and to vectorize the cell deformation over time.




 

Photoacoustic Imaging

    My undergraduate's and Master's studies focused on photoacoustic imaging under the supervisions of Meng-Lin Li, PhD and Pai-Chi Li, PhD respectively. Photoacoustic imaging is a hybrid biomedical imaging modality, combining optical excitation with ultrasonic detection. Photoacoustic imaging provides the ability which conventional ultrasonic imaging lacks, to detect hemoglobin, melanin, and other light-absorbing contrasts, but with greater imaging depth than pure optical imaging relying on ballistic photons.


    Dual-wavelength Photoacoustic Molecular Microscopy for Three-dimensional Cell Culture Systems

    The proposed microscope was integrated with an automatic imaging system and photoacoustics with contrast agents for studying tumor-immune interaction in a 3D cell culture system.


    • Proposed a live-cell imaging system integrated with optics, laser scanning mechanism, and synchronization.

    • Constructed a LabVIEW-based and user-friendly interface for imaging operation.

    • Architected an image reconstruction algorithm for 3D photoacoustic images under the MATLAB interface.

    • Built protocols including contrast agents and 3D cell culture systems for the image system under collaboration.


    Photoacoustic Angio-cam for Subcutaneous Vasculature Imaging


    This work was to verify the feasibility of Photoacoustic Angio-cam (PA-Cam) for subcutaneous vasculature imaging. The proposed PA-Cam was based on digicam-like photoacoustics, which was integrated with pulse laser, acoustic lens, and 2D acoustic detection.


    • Proposed a prototype acoustic-lens-based photoacoustic imaging system for diagnosis of vascular diseases.

    • Integrated a defocused scanning method with a focused ultrasonic transducer to simulate a 2D acoustic detector.

    • Verified the feasibility of a 2D CMOS-based acoustic detector under collaboration.


 

Fellowships / Grants


    • 2021 Government Scholarship to Study Abroad ($32,000) , Ministry of Education, Taiwan.

    • 2013 College Student Research Grant ($1,600) , National Science Council, Taiwan.

    • 2012 Exchange Scholarship to Mainland China ($1,000) , National Tsing Hua University, Taiwan.


 

Honors & Awards


    • First place, ASME-BED PhD-level Student Paper Competition, 2021 Summer Biomechanics, Bioengineering and Biotransport Conference (SB3C).

    • Finalist, ASME-BED PhD-level Student Paper Competition, 2019 Summer Biomechanics, Bioengineering and Biotransport Conference (SB3C).

    • Outstanding Poster Award, 2018 Carnegie Mellon Forum on Biomedical Engineering.

    • Best Freshman Counselor, National Tsing Hua University, Taiwan, 2014.

    • First Prize, Contest of Special Topics on Implementation, Department of Electrical Engineering, National Tsing Hua University, Taiwan, 2014.

    • Honorable Mention in Essay, Spring Chinese Writing Contest, National Tsing Hua University, Taiwan, 2011.


 

Service / Teaching Experience


    Judges for ASME-BED BS-level Student Paper Competition
    Summer Biomechanics, Bioengineering and Biotransport Conference (SB3C)

    2019, 2021

    Business Manager (Acting President)
    Taiwanese Scholars Society, University of Pittsburgh

    2020 – 2021

    Teaching Assistant
    Department of Bioengineering, University of Pittsburgh

    • (2020 Spring) Biomedical Application of Signal Processing

    • (2019 Fall) Radiofrequency Medical Devices

    2019 – 2020

    Freshman Counselor
    Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University

    2012 – 2014


 

Publications

  • Journal Articles

    1. Po-Yi Lee, Yi Hua, Bryn L. Brazile, Bin Yang, Ian A. Sigal. A workflow for 3D reconstruction and quantification of the monkey optic nerve head vascular network. Journal of Biomechanical Engineering. (Revision Submitted)

    2. Po-Yi Lee, Bin Yang, Yi Hua, Susannah Waxman, Ziyi Zhu, Fengting Ji, Ian A Sigal. Real-time imaging of optic nerve head collagen microstructure and biomechanics. Experimental Eye Research,, 217, 109867, April 2022. [Link]

    3. Susannah Waxman, Bryn L. Brazile, Bin Yang, Alexandra L. Gogola, Yi Hua, Po Lam, Po-Yi Lee, Andrew P. Voorhees, Joseph F. Rizzo III, Tatjana C. Jakobs, Ian A. Sigal. Lamina cribrosa vessel and collagen beam networks are distinct. Experimental Eye Research, 215, 108916, December 2021. [Link]

    4. Bin Yang, Po-Yi Lee, Yi Hua, Bryn Brazile, Susannah Waxman, Fengting Ji, Ziyi Zhu, Ian A. Sigal. Instant polarized light microscopy for imaging collagen microarchitecture and dynamics. Journal of Biophotonics, e202000326, February 2021. [Link]

    5. Yun-Chi Tsai, Wei-Chun Tang, Christine SiokLan Low, Yen-Ting Liu, Jyun-Sian Wu, Po-Yi Lee, Yi-Ling Lin, Pakorn Kanchanawong, Liang Gao, Lindsay Chen, Bi-Chang Chen. Rapid High Resolution 3D Imaging of Expanded Biological Specimens with Lattice Light Sheet Microscopy. Methods, 174, 11-19, March 2020. [Link]

    6. Xiaofei Bai, Michael Melesse, Christopher G. Sorensen Turpin, Dillon E. Sloan, Chin-Yi Chen, Wen-Cheng Wang, Po-Yi Lee, James R. Simmons, Benjamin Nebenfuehr, Diana Mitchell, Lindsey R. Klebanow, Nicholas Mattson, Eric Betzig, Bi-Chang Chen, Dhanya Cheerambathur, Joshua N. Bembenek. Aurora B functions at the apical surface after specialized cytokinesis during morphogenesis in C. elegans. Development, 147(1) January 2020. [Link]

    7. Chin-Yi Chen, Yen-Ting Liu, Chieh-Han Lu, Po-Yi Lee, Jyun-Sian Wu, Peilin Chen, Bi-Chang Chen. The Applications of Lattice Light-Sheet Microscopy for Functional Volumetric Imaging of Hippocampal Neurons in a Three-Dimensional Culture System. Micromachines, 10(9), 599, September 2019. [Link]

  • Conference Proceedings

    1. Po-Yi Lee, Jason Walker, Yi Hua, Bryn Brazile, Ian A. Sigal. Integrating capillary flow modeling and geometric quantification into reconstructed 3d capillary networks of the optic nerve head. Proceedings of Summer Biomechanics, Bioengineering, and Biotransport Conference (SB3C), 241-42, June 2021. [Link]

    2. Yi Hua, Jason Walker, Po-Yi Lee, Fengting Ji, Haiden McDonald, Pedro Pallares, Bryn Brazille, Ian A. Sigal. Factors influencing minimum lamina cribrosa oxygen concentration. Proceedings of Summer Biomechanics, Bioengineering, and Biotransport Conference (SB3C), 687-88, June 2021. [Link]

    3. Grace Ingram, Po-Yi Lee, Benjamin Bernarding, Ian A. Sigal, Bin Yang. Real-time structured polarized light imaging of dynamics of thick collagenous tissues. Proceedings of SPIE – Emerging Digital Micromirror Device Based Systems and Applications XIII, 116980A, March 2021. [Link]

    4. Po-Yi Lee, Bin Yang, Gosia Fryc, Yi Hua, Ian A. Sigal. Direct visualization and measurement of stretch-induced uncrimping of the collagen fibers of the optic nerve head. Proceedings of Summer Biomechanics, Bioengineering, and Biotransport Conference (SB3C), 1032-33, June 2020. [Link]

    5. Bingrui Wang, Po-Yi Lee, Bin Yang, Fengting Ji, Ziyi Zhu, Yi Hua, Ian A. Sigal. Tissue collagen fibers are often interwoven. so what? in support of considering fiber interweaving. Proceedings of Summer Biomechanics, Bioengineering, and Biotransport Conference (SB3C), 1042-43, June 2020. [Link]

    6. Po-Yi Lee, Bin Yang, Yi Hua, Bryn Brazile, Fengting Ji, Ziyi Zhu, Gosia A. Fryc, Ian A. Sigal. Instant polarized light microscopy for real-time wide-field visualization of collagen architecture. Proceedings of SPIE – Label-free Biomedical Imaging and Sensing, 112510Y, March 2020. [Link]

    7. Po-Yi Lee, Bin Yang, Ian A. Sigal. Real-time measurement of collagen architecture and deformations at sub-micron resolution. Proceedings of Summer Biomechanics, Bioengineering, and Biotransport Conference (SB3C), 341-42, June 2019. [Link]

    8. Bin Yang, Po-Yi Lee, Bryn Brazile, Ian A. Sigal. Snapshot-polarized light microscopy to visualize and quantify collagenous soft tissue microstructure at 156 frames/second. Proceedings of Summer Biomechanics, Bioengineering, and Biotransport Conference (SB3C), 202-03, June 2019. [Link]

    9. Po-Yi Lee, Wei-Wen Liu, Shu-Ching Chen, Pai-Chi Li. Dual-wavelength optical-resolution photoacoustic microscopy for cells with gold nanoparticle bioconjugates in three-dimensional cultures. Proceedings of SPIE – Photons Plus Ultrasound: Imaging and Sensing, 97081N, March 2016. [Link]

  • Presentations in International Conferences

    1. Presenter underlined if not Po-Yi Lee.

    2. Po-Yi Lee, Jason A. Walker, Yi Hua, Ian A. Sigal. Quantitative imaging of optic nerve head collagen microstructure and micromechanics using instant polarized light microscopy E-meeting i2Eye 2021 Innovative Imaging of Eye Disease, Virtual meeting, October 13 – 15, 2021.

    3. Po-Yi Lee, Jason A. Walker, Yi Hua, Ian A. Sigal. Integrating capillary flow modeling and geometric quantification into reconstructed 3d capillary networks of the optic nerve head. Summer Biomechanics, Bioengineering, and Biotransport Conference (SB3C), Virtual meeting, June 14 – 18, 2021.

    4. Yi Hua, Jason Walker, Po-Yi Lee, Fengting Ji, Haiden McDonald, Pedro Pallares, Bryn Brazille, Ian A. Sigal. Factors influencing minimum lamina cribrosa oxygen concentration. Summer Biomechanics, Bioengineering, and Biotransport Conference (SB3C), Virtual meeting, June 14 – 18, 2021.

    5. Grace Ingram, Po-Yi Lee, Benjamin Bernarding, Ian A. Sigal, Bin Yang. Real-time structured polarized light imaging of dynamics of thick collagenous tissues. SPIE Photonics West BiOS Conference, Virtual meeting, March 6 – 11, 2021.

    6. Po-Yi Lee, Bin Yang, Gosia Fryc, Yi Hua, Ian A. Sigal. Direct visualization and measurement of stretch-induced uncrimping of the collagen fibers of the optic nerve head. Summer Biomechanics, Bioengineering, and Biotransport Conference (SB3C), Virtual meeting, June 17 – 20, 2020.

    7. Bingrui Wang, Po-Yi Lee, Bin Yang, Fengting Ji, Ziyi Zhu, Yi Hua, Ian A. Sigal. Tissue collagen fibers are often interwoven. so what? in support of considering fiber interweaving. Summer Biomechanics, Bioengineering, and Biotransport Conference (SB3C), Virtual meeting, June 17 – 20, 2020.

    8. Po-Yi Lee, Bin Yang, Ziyi Zhu, Fengting Ji, Yi Hua, Ian A. Sigal. Microstructural evidence that lamina cribrosa beams (LC), peripapillary sclera (PPS) and central retinal artery (CRA) have distinct mechanical behaviors when stretched. The Association for Research in Vision and Ophthalmology (ARVO), May 3 – 7, 2020. (Cancelled due to COVID-19)

    9. Yi Hua, Jason A. Walker, Po-Yi Lee, Bryn Brazile, Ian A. Sigal. 3D eye-specific analysis of factors influencing lamina cribrosa oxygen concentration. The Association for Research in Vision and Ophthalmology (ARVO), May 3 – 7, 2020. (Cancelled due to COVID-19)

    10. Fengting Ji, Bin Yang, Yi Hua, Po-Yi Lee, Ziyi Zhu, Ian A Sigal. Characterization of lamina cribrosa beam insertion into the sclera canal in sheep, pig, monkey, and human. The Association for Research in Vision and Ophthalmology (ARVO), May 3 – 7, 2020. (Cancelled due to COVID-19)

    11. Bin Yang, Po-Yi Lee, Melissa Echard, Ziyi Zhu; Fengting Ji, Benjamin Bernarding, Ian A. Sigal. Real-time structured polarized light imaging (rtSPLI) for thick ocular tissue dynamics. Imaging in the Eye Conference, May 1 – 2, 2020. (Cancelled due to COVID-19)

    12. Po-Yi Lee, Bin Yang, Yi Hua, Bryn Brazile, Fengting Ji, Ziyi Zhu, Gosia A. Fryc, Ian A. Sigal. Instant polarized light microscopy for real-time wide-field visualization of collagen architecture. SPIE Photonics West BiOS Conference, San Francisco, California, February 1-6, 2020.

    13. Bin Yang, Po-Yi Lee, Yi Hua, Bryn Brazile, Ziyi Zhu, Fengting Ji, Ian A. Sigal. Multi-scale elastography: imaging the collagen fibers and their interactions during mechanical testing. SPIE Photonics West BiOS Conference, San Francisco, California, February 1-6, 2020.

    14. Po-Yi Lee, Bin Yang, Ian A. Sigal. Real-time measurement of collagen architecture and deformations at sub-micron resolution. Summer Biomechanics, Bioengineering, and Biotransport Conference (SB3C), Seven Springs, Pennsylvania, June 25 – 28, 2019.

    15. Bin Yang, Po-Yi Lee, Bryn Brazile, Ian A. Sigal. Snapshot-polarized light microscopy to visualize and quantify collagenous soft tissue microstructure at 156 frames/second. Summer Biomechanics, Bioengineering, and Biotransport Conference (SB3C), Seven Springs, Pennsylvania, June 25 – 28, 2019.

    16. Ian A. Sigal, Bin Wang, Bingrui Yang, Po-Yi Lee, Tian Yong Foong, Bryn Brazile, Yi Hua. Collagen fiber interweaving strongly influences sclera stiffness, and likely plays a central role in globe mechanics. The Association for Research in Vision and Ophthalmology (ARVO), Vancouver, British Columbia, Canada, April 28 – May 2, 2019.

    17. Ian A. Sigal, Po-Yi Lee,Bryn Brazile, Po Lam, Ziyi Zhu, Yi Hua, Bin Yang. Real-time measurement of lamina cribrosa and sclera collagen architecture and mechanics at sub-micron resolution. ARVO Imaging in the Eye Conference, Vancouver, British Columbia, Canada, April 27, 2019.

    18. Chin-Yi Chen, Yen-Ting Liu, Po-Yi Lee, Yun-Chi Tsai, Peilin Chen, Bi-Chang Chen. The subcellular voltage and calcium dynamics of hippocampal neurons on matrigel-based three dimensional culture are revealed by lattice light-sheet microscopy. Conference: Cell Biology of the Neuron: Emerging Themes in Neuronal Trafficking, Homeostasis, Synapse Function and Disease Mechanisms, New Hampshire, United State, une 24 – 29, 2018.

    19. Po-Yi Lee, Chi-Yi Chen, Yu-Ting Tseng, Chung-Chih Lin, Bi-Chang Chen. Visualization and quantification of mitochondrial dynamics with lattice light-sheet microscopy. 2018 Focus on Microscopy, Singapore, Singapore, March 25 – 28, 2018.

    20. Po-Yi Lee, Nien-Ching Ho, Kai-Heng Lin, Ling-Ya Huang, Pai-Chi Li. Multiwave imaging technologies for three-dimensional cell culture systems. 2016 Global Conference on Biomedical Engineering, Taipei, Taiwan, August 17 – 19, 2016.

    21. Po-Yi Lee, Wei-Wen Liu, Shu-Ching Chen, Pai-Chi Li. 3D photoacoustic microscopy for cell tracking. 2016 European Molecular Imaging Meeting, Utrecht, Netherlands, March 8 – 10, 2016.

    22. Po-Yi Lee, Wei-Wen Liu, Shu-Ching Chen, Pai-Chi Li. Dual-wavelength optical-resolution photoacoustic microscopy for cells with gold nanoparticle bioconjugates in three-dimensional cultures. SPIE Photonics West BiOS Conference, San Francisco, California , February 13 – 18, 2016.

  • Presentations in Local Conferences

    1. Presenter underlined if not Po-Yi Lee.

    2. Po-Yi Lee, Jason A. Walker, Yi Hua, Ian A. Sigal. Effects of capillary geometry on optic nerve head hemodynamics. University of Pittsburgh Vision Research Day, Virtual meeting, June 11, 2021.

    3. Yi Hua, Jason A. Walker, Po-Yi Lee, Fengting Ji, Bryn Brazile, Ian A. Sigal. Eye-specific parametric analysis of lamina cribrosa oxygenation. 47th Annual Northeast Bioengineering Conference (NEBEC): New research frontiers and educational landscapes in biomedical engineering, Virtual meeting, March 23 – 25, 2021.

    4. Grace Ingram, Po-Yi Lee, Benjamin Bernarding, Ian A. Sigal, Bin Yang. High-speed structured polarized light imaging of tissue dynamics. 47th Annual Northeast Bioengineering Conference (NEBEC): New research frontiers and educational landscapes in biomedical engineering, Virtual meeting, March 23 – 25, 2021.

    5. Po-Yi Lee, Bin Yang, Yi Hua, Susannah Waxman, Ziyi Zhu, Fengting Ji, Ian A. Sigal. Real-time imaging of the stretch-induced changes in the optic nerve head collagen architecture. Carnegie Mellon Forum on Biomedical Engineering, Virtual meeting, September 18 – 19, 2020.

    6. Grace Ingram, Po-Yi Lee, Benjamin Bernarding, Ian A. Sigal, Bin Yang. High-speed structured polarized light imaging of tissue dynamics. Carnegie Mellon Forum on Biomedical Engineering, Virtual meeting, September 18 – 19, 2020.

    7. Fengting Ji, Bin Yang, Yin Hua, Po-Yi Lee, Ziyi Zhu, Ian A. Sigal. Support at the edge: lamina cribrosa beam insertions in sheep, pig, monkey and human. University of Pittsburgh BioE Day, February 27, 2020.

    8. Po-Yi Lee, Bin Yang, Ian A. Sigal. Snapshot polarized light microscopy for quantifying collagen fiber orientation in ocular tissues. Vision Research Day, Pittsburgh, Pennsylvania, June 12, 2019.

    9. Po-Yi Lee, Bin Yang, Ian A. Sigal. Snapshot polarized light microscopy for quantifying collagen fiber orientation in ocular tissues. Carnegie Mellon Forum on Biomedical Engineering, Pennsylvania, September 21, 2018.

    10. Po-Yi Lee, Nien-Ching Ho, Kai-Heng Lin, Ling-Ya Huang, Pai-Chi Li. Multiwave imaging technologies for three-dimensional cell culture systems. Annual Symposium on Biomedical Engineering and Technology, Taipei, Taiwan, November 11 – 13, 2015.

    11. Po-Yi Lee, Hao-Wei Lee, You-Lin Chen, Yi-Wen Liu. Investigation of Image Processing Methods for Music Score Recognition. 2013 National Computer Symposium, Taichung, Taiwan, December 13-14, 2013.