Paper Info
Title
A Novel Low-Dose Dual-Energy Imaging Method for a Fast-Rotating Gantry-Type CT Scanner
Abstract
CT scan by use of a beam-filter placed between the x-ray source and the patient allows a single-scan low-dose dual-energy imaging with a minimal hardware modification to the existing CT systems. We have earlier demonstrated the feasibility of such imaging method with a multi-slit beam-filter reciprocating along the direction perpendicular to the CT rotation axis in a cone-beam CT system. However, such method would face mechanical challenges when the beam-filter is supposed to cooperate with a fast-rotating gantry in a diagnostic CT system. In this work, we propose a new scanning method and associated image reconstruction algorithm that can overcome these challenges. We propose to slide a beam-filter that has multi-slit structure with its slits being at a slanted angle with the CT gantry rotation axis during a scan. A streaky pattern would show up in the sinogram domain as a result. Using a notch filter in the Fourier domain of the sinogram, we removed the streaks and reconstructed an image by use of the filtered-backprojection algorithm. The remaining image artifacts were suppressed by applying l <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> norm based smoothing. Using this image as a prior, we have reconstructed low- and high-energy CT images in the iterative reconstruction framework. An image-based material decomposition then followed. We conducted a simulation study to test its feasibility using the XCAT phantom and also an experimental study using the Catphan phantom, a head phantom, an iodine-solution phantom, and a monkey in anesthesia, and showed its successful performance in image reconstruction and in material decomposition.
Year
DOI
Venue
2021
10.1109/TMI.2020.3044357
IEEE Transactions on Medical Imaging
Keywords
DocType
Volume
Algorithms,Artifacts,Cone-Beam Computed Tomography,Head,Humans,Image Processing, Computer-Assisted,Phantoms, Imaging,Tomography, X-Ray Computed
Journal
40
Issue
ISSN
Citations 
3
0278-0062
0
PageRank 
References 
Authors
0.34
0
10
Name
Order
Citations
PageRank
Sanghoon Cho100.34
Seoyoung Lee200.34
Jong-Ha Lee3626.51
Donghyeon Lee468.27
Hyoyi Kim500.34
Jong-Hyun Ryu641.44
Kilhwan Jeong700.34
Kyu-Gyum Kim800.34
Kwon-Ha Yoon9113.64
Seungryong Cho10145.34