2024
12:00 PM - 01:00 PM
Tuesday Tue
Location
Medical Physics Seminar - Emil Sidky
Quantitative Imaging with Dual-Energy X-Ray Computed Tomography
Time:
12:00pm – 1:00pm Seminar & Discussion
Location:
Zoom Webinar
Webinar Registration:
https://stanford.zoom.us/webinar/register/WN_unEgda5ZSBqjAaXJNRwWjg
Check your email for the Zoom webinar link after you have registered
Speaker
Dr. Emil Sidky, Ph.D., DABR, Research Professor, Department of Radiology at University of Chicago
Dr. Sidky is Research Professor in the Department of Radiology at The University of Chicago. He received his B.S. degree (1988) in Physics, Astronomy- Physics, and Mathematics from the University of Wisconsin-Madison. He went on to obtain his M.S (1991) and Ph.D (1993) in Physics from The University of Chicago. Dr. Sidky worked as a post-doctoral research assistant in Atomic Physics at the University of Copenhagen (1993-1996), University of Bielefeld (1996), and Kansas State University (1996-2001). In 2001, Dr. Sidky switched to medical imaging and joined the lab of our Editor-in-Chief, Dr. Pan; most recently, he was promoted to Research Professor in 2018. Dr. Sidky has published approximately 120 papers, and about 90 of them are in medical imaging. His theoretical work has mainly focused on X-ray tomography with sparse or limited-angular range sampling. He has also applied advanced techniques for non-smooth or non-convex large-scale optimization applied to imaging. His application work has centered on tomographic breast imaging, CT and tomosynthesis, and developing image reconstruction algorithms and calibration techniques for spectral CT scanners based on photon-counting detectors.
Abstract
Dual-energy computed tomography (DECT) involves acquiring two sets of X-ray transmission data, most commonly, using two different X-ray source potentials. The acquisition of the additional set of transmission data, over standard CT, has three potential benefits enabling: true quantitative imaging, where pixel values can accurately reflect physical quantities such as material density or electron density; correction of beam-hardening artifacts; and improved contrast-to-noise ratio. This introductory-level talk will focus on the processing of the transmission data and image reconstruction methods used in DECT with the goal of conveying an understanding of DECT capabilities. The talk will begin with an introduction to standard CT data processing and its short-comings, namely its non-quantitativeness and susceptibility to beam-hardening, then move on to how DECT addresses these issues. Data processing/image reconstruction in DECT falls into three classes of algorithms: post-processing or image-based analysis; pre-processing of transmission data into basis sonograms, and one-step direct image reconstruction from DECT transmission data. These methods will be covered, explaining advantages and disadvantages of each. Finally, I will briefly touch on various topics of current research in DECT and, more generally, spectral CT.