KARL 3D reconstruction technique can reduce radiation dose in breath-hold chest PET/CT
JING Yudong
CHAI Leiying
GAO Lin
CUI Xiao
XU Jiwei
LI Hui
LIU Wenhui
LI Kun
CHENG Zhaoping
DUAN Yanhua
Abstract：Objective To investigate the application value of KARL 3D iterative reconstruction technology in chest breath-hold PET/CT scanning.Methods Ninety-three patients with suspected pulmonary nodules undergoing chest breath-hold PET/CT scans at the First Affiliated Hospital of Shandong First Medical University from March 2022 to March 2023 were prospectively enrolled.Participants were stratified into three groups(10,20,30 mAs)based on tube current settings for breath-hold attenuation correction CT(ACCT).ACCT images acquired under different low-dose protocols were reconstructed using both KARL 3D and conventional filtered back projection(FBP)algorithms.Quantitative comparisons of CTmean,noise(SD),and signal-to-noise ratio(SNR)were performed for the aorta,main pulmonary artery,and axillary adipose tissue between reconstruction methods.Comparative analysis was further conducted between KARL 3D-reconstructed images and FBP-reconstructed diagnostic-dose images(FBP-reconstructed 130-mAs images,FBP130)regarding SD,SNR,and effective dose(ED).Results At all dose levels,no statistically significant differences were observed in CT mean between KARL 3D and FBP reconstructions(P>0.05).After KARL 3D reconstruction,the standard deviation(SD)decreased and the SNR increased in the images,with statistically significant differences(P<0.001).For the 10 mAs and 20 mAs groups,KARL 3D-reconstructed images showed statistically significant differences in SD,SNR and ED compared with FBP130(P<0.001).The 30 mAs protocol combined with KARL 3D achieved comparable SD and SNR to FBP130(P>0.05),while reducing ED by 68%.Conclusion The 30 mAs protocol with KARL 3D(grade 5)reconstruction produces diagnostic-quality images equivalent to conventional high-resolution CT-FBP reconstructions,simultaneously achieving attenuation correction.This approach reduces radiation exposure by approximately 76%compared with conventional diagnostic CT plus low-dose ACCT protocols.
Keywords：positron-emission tomographyKARL 3D iterativefilter backup projectionimage qualitylow-dose
Publication Date：2025-06-20
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 661-667 )