Basic Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. May 7, 2015; 21(17): 5259-5270
Published online May 7, 2015. doi: 10.3748/wjg.v21.i17.5259
Low contrast medium and radiation dose for hepatic computed tomography perfusion of rabbit VX2 tumor
Cai-Yuan Zhang, Yan-Fen Cui, Chen Guo, Jing Cai, Ya-Fang Weng, Li-Jun Wang, Deng-Bin Wang
Cai-Yuan Zhang, Yan-Fen Cui, Chen Guo, Jing Cai, Ya-Fang Weng, Li-Jun Wang, Deng-Bin Wang, Department of Radiology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China
Author contributions: Zhang CY and Wang DB designed the experiments; Zhang CY, Cui YF, Guo C, Cai J and Weng YF performed the experiments; Zhang CY, Cui YF, Guo C and Wang LJ analyzed the data; Cui YF, Cai J and Weng YF contributed reagents/materials/analysis tools; Zhang CY and Wang DB wrote the paper.
Supported by National Natural Science Foundation of China, No. NSFC 81171389; Key Program of Basic Research from Shanghai Municipal Science and Technology Commission, No. 12JC1406500; and the Program of Shanghai Municipal Health Outstanding Discipline Leader, No. XBR 2013110.
Ethics approval: The protocol was approved by the Ethics Committee of Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine (Approval No, XHEC-F-2013-016).
Institutional animal care and use committee: All procedures involving animals were reviewed and approved by the Institutional Animal Care and Use Committee of Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine.
Conflict-of-interest: There are no conflicts of interest by any of the participating authors.
Data sharing: Technical appendix, statistical code, and dataset are available from the corresponding author Dengbin Wang at dbwang8@aliyun.com, who will provide a permanent, citable and open-access home for the dataset.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Deng-Bin Wang, MD, PhD, Professor, Chairman, Department of Radiology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, No. 1665 Kongjiang Road, Shanghai 200092, China. dbwang8@aliyun.com
Telephone: +86-21-25078999-7030
Received: October 25, 2014
Peer-review started: October 28, 2014
First decision: December 26, 2014
Revised: January 18, 2015
Accepted: February 11, 2015
Article in press: February 11, 2015
Published online: May 7, 2015
Processing time: 200 Days and 6.5 Hours
Abstract

AIM: To evaluate the feasibility of low contrast medium and radiation dose for hepatic computed tomography (CT) perfusion of rabbit VX2 tumor.

METHODS: Eleven rabbits with hepatic VX2 tumor underwent perfusion CT scanning with a 24-h interval between a conventional tube potential (120 kVp) protocol with 350 mgI/mL contrast medium and filtered back projection, and a low tube potential (80 kVp) protocol with 270 mgI/mL contrast medium with iterative reconstruction. Correlation and agreement among perfusion parameters acquired by the conventional and low dose protocols were assessed for the viable tumor component as well as whole tumor. Image noise and tumor-to-liver contrast to noise ratio during arterial and portal venous phases were evaluated.

RESULTS: A 38% reduction in contrast medium dose (360.1 ± 13.3 mgI/kg vs 583.5 ± 21.5 mgI/kg, P < 0.001) and a 73% decrease in radiation dose (1898.5 mGy • cm vs 6951.8 mGy • cm) were observed. Interestingly, there was a strong positive correlation in hepatic arterial perfusion (r = 0.907, P < 0.001; r = 0.879, P < 0.001), hepatic portal perfusion (r = 0.819, P = 0.002; r = 0.831, P = 0.002), and hepatic blood flow (r = 0.945, P < 0.001; r = 0.930, P < 0.001) as well as a moderate correlation in hepatic perfusion index (r = 0.736, P = 0.01; r = 0.636, P = 0.035) between the low dose protocol with iterative reconstruction and the conventional protocol for the viable tumor component and the whole tumor. These two imaging protocols provided a moderate but acceptable agreement for perfusion parameters and similar tumor-to-liver CNR during arterial and portal venous phases (5.63 ± 2.38 vs 6.16 ± 2.60, P = 0.814; 4.60 ± 1.27 vs 5.11 ± 1.74, P = 0.587).

CONCLUSION: Compared with the conventional protocol, low contrast medium and radiation dose with iterative reconstruction has no significant influence on hepatic perfusion parameters for rabbits VX2 tumor.

Keywords: Low radiation dose; Low concentration contrast medium; Perfusion computed tomography; Liver; VX2 tumor

Core tip: We performed hepatic computed tomography (CT) perfusion of liver VX2 tumor in rabbits by using both conventional tube potential (120 kVp) protocol with 350 mgI/mL concentration contrast medium and low tube potential (80kVp) protocol with 270 mgI/mL concentration contrast medium at a 24-h interval. This study demonstrated that there were a 38% reduction in contrast medium consumption and a 73% reduction in radiation dose for low dose protocol without significant influence on the hepatic perfusion parameters. It is promising that hepatic CT perfusion with low contrast medium dose and tube potential protocol may be clinically used to decrease radiation dose and the risk of contrast-induced nephropathy.