Jump to Navigation


Medical Physics Seminar

Thursday, April 11, 2013 - 4:10pm - 5:15pm
Columbia University Morningside Campus S.W. Mudd, Room 214

Elizabeth Hillman
, PhD
Associate Professor
Department of Biomedical Engineering, Columbia University

"Imaging with Light (Biophotonics in Brief)"

Abstract:  All medical imaging modalities rely on some form of propagating wave or radiation to map tissue properties. Just as x-rays and ultrasound detect specific physical properties of the body based on their particular interactions, light (ranging from UV to infrared) can be used for medical diagnostics and in-vivo assessment of tissues. This field is called Biophotonics. Using light brings some significant benefits as well as challenges. The major challenge of 'optical imaging' is light scattering, which limits penetration of light into tissue leading to poor resolution for deep tissue imaging. This facet of biophotonics means that a very wide range of different optical imaging modalities exists, specific to particular medical applications. Some optical imaging modalities can deliver high, even microscopic resolution of superficial tissues (such as endoscopy or retinal imaging) while others can provide low resolution in larger tissue volumes, such as diffuse optical tomography of the breast or infant brain. The major benefit of imaging with light is its specificity and high sensitivity to absorbers, scatterers and fluorophores within living tissue, whether endogenous, like oxy- and deoxy-hemoglobin, melanin, NADH and FAD, or exogenous, such as indocyanine green dye. Optical imaging techniques are also typically inexpensive, fast, and portable compared to conventional imaging modalities. Biophotonics is an emerging field, with increasing importance in clinical care. A general overview of the principles of biophotonics, as well as examples of different techniques and applications will be given.

Bio: Elizabeth Hillman is an Associate Professor of Biomedical Engineering and Radiology at Columbia. She completed her post-doctoral training at the Martinos Center for Biomedical Imaging at Massachusetts General Hospital / Harvard Medical School, and both her undergraduate degree in Physics, and PhD in Medical Physics and Bioengineering at University College London. Dr Hillman's research program focuses on the development of novel in-vivo optical imaging and microscopy tools. She primarily uses these tools to understand the way that neuronal activity modulates blood flow in the living brain, a topic that is highly important for understanding the origins of imaging contrast in functional MRI.

John Arbo, Coordinator