PhD Defense: "Dynamic Imaging of Function and Morphogenesis in the Developing Heart"

Jungho Ohn

February 21st (Thursday), 11:00am
Harold Frank Hall (HFH), Rm 4164

Congenital heart disease, the most common birth defect, occurs up to 5% of live births in humans. Understanding the relationship between morphology and function during development in the embryonic heart has important medical implications. Our studies focus on developing non-invasive heart imaging tools to observe the dynamics of morphogenesis while the heart is growing and functioning. Our approach consists in setting up a computer-driven automated microscope equipped with high-speed and sensitive cameras, implementing sample mounting protocols, and developing image reconstruction and analysis software. In order to improve the specificity with which structures can be imaged in the beating heart, we developed multi-modal microscopy by combining high-speed and multi-color sequences taken in brightfield and fluorescence microscopy, respectively. In an effort to improve axial resolution in conventional widefield microscopy, we implemented dynamic optical projection tomography. To quantify variability when characterizing heart function, we developed in vivo high-throughput microscopy. Finally, we carried out joint and quantitative studies of heart morphogenesis and functiogenesis by use of a novel imaging technique, burst time-lapse microscopy (BTLM). This allowed building time-lapses revealing the morphogenesis of the highly dynamic cardiac valve leaflets as they progressively prevent retrograde flow between cardiac chambers. This work provides new insights into cardiogenesis and should allow better understanding of normal and diseased development. We anticipate that the developed tools will be applicable for imaging a wide range of dynamic biological samples.

About Jungho Ohn:

Jungho Ohn received the B.E. degree in Information and Telecommunication Engineering from the Korea Aerospace University, South Korea, in 2005. He worked as a research engineer at Automotive Electronics R&D Center, Hyundai Motor Company until 2006. He obtained the M.S. degree in Electrical and Computer Engineering (ECE) from the University of California, Santa Barbara (UCSB), California, USA, in 2009, where he is currently pursuing the Ph.D. degree in the area of signal and image processing. His research interests include biomedical imaging, signal/image processing and analysis, and computer vision. He was a recipient of the best student paper award at IEEE International Symposium on Biomedical imaging (ISBI’11), Chicago, IL, USA, 2011 and the Summer Fellowship from ECE, UCSB in 2009, 2012. He will join GE Ultrasound Korea as a system engineer after graduation.

Hosted by: Professor Michael Liebling