[Three-dimensional low-dose CT volume reconstruction based on non-local weights optimization and GPU acceleration].
Concerns have been raised over x-ray radiation dose associated with repeated computed tomography (CT) scans for tumor surveillance and radiotherapy planning. In this paper, we present a low-dose CT image reconstruction method for improving low-dose CT image quality. The method proposed exploited rich redundancy information from previous normal-dose scan image for optimizing the non-local weights construction in the original non-local means (NLM)-based low-dose image reconstruction. The objective 3D low-dose volume and the previous 3D normal-dose volume were first registered to reduce the anatomic structural dissimilarity between the two datasets, and the optimized non-local weights were constructed based on the registered normal-dose volume.  To increase the efficiency of this method, GPU was utilized to accelerate the implementation. The experimental results showed that this method obviously improved the image quality, as compared with the original NLM method, by suppressing the noise-induced artifacts and preserving the edge information.
Institute of Medical Information and Technology, Southern Medical University, Guangzhou, China. zxln@fimmu.com
Xi-le
XL
Zhang
Ling-ling
LL
Tian
Jing
J
Huang
Jian-hua
JH
Ma
Hua
H
Zhang
Qian-jin
QJ
Feng
Wu-fan
WF
Chen
D000465:Algorithms; D016477:Artifacts; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011835:Radiation Protection / Q000592:standards*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods* / Q000592:standards; D014057:Tomography, X-Ray Computed / Q000379:methods*