Observational Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Radiol. Nov 28, 2019; 11(11): 134-143
Published online Nov 28, 2019. doi: 10.4329/wjr.v11.i11.134
Comparison of free breathing and respiratory triggered diffusion-weighted imaging sequences for liver imaging
Janio Szklaruk, Jong Bum Son, Wei Wei, Priya Bhosale, Sanaz Javadi, Jingfei Ma
Janio Szklaruk, Priya Bhosale, Sanaz Javadi, Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, United States
Jong Bum Son, Jingfei Ma, Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, United States
Wei Wei, Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, United States
Author contributions: All authors contributed to the manuscript preparation, study design and data analysis; Wei W performed all statistical analyses; Bhosale P, Javadi S, Son JB and Szklaruk J acquired the data; Ma J and Szklaruk J contributed to the overall study design and implementation, data analysis.
Institutional review board statement: This study was approved by the University of Texas MD Anderson Cancer Center Institutional Review Board.
Conflict-of-interest statement: All authors declare that they have nothing to disclose except for Ma J. Ma J has ongoing financial relationships with GE Healthcare, Siemens Healthineers, and C4 Imaging. There are no family members who present a potential conflict of interest.
Data sharing statement: Not applicable
STROBE statement: The authors have read the STROBE checklist, and the manuscript was prepared and revised according to the STROBE checklist.
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/
Corresponding author: Janio Szklaruk, MD, PhD, Doctor, Professor, Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Unit 1473, Houston, TX 77030, United States. jszklaru@mdanderson.org
Telephone: +1-713-7453230
Received: June 25, 2019
Peer-review started: June 29, 2019
First decision: August 2, 2019
Revised: August 26, 2019
Accepted: September 25, 2019
Article in press: September 25, 2019
Published online: November 28, 2019
Processing time: 148 Days and 17 Hours
Abstract
BACKGROUND

Diffusion-weighted imaging (DWI) has become a useful tool in the detection, characterization, and evaluation of response to treatment of many cancers, including malignant liver lesions. DWI offers higher image contrast between lesions and normal liver tissue than other sequences. DWI images acquired at two or more b-values can be used to derive an apparent diffusion coefficient (ADC). DWI in the body has several technical challenges. This include ghosting artifacts, mis-registration and susceptibility artifacts. New DWI sequences have been developed to overcome some of these challenges. Our goal is to evaluate 3 new DWI sequences for liver imaging.

AIM

To qualitatively and quantitatively compare 3 DWI sequences for liver imaging: free-breathing (FB), simultaneous multislice (SMS), and prospective acquisition correction (PACE).

METHODS

Magnetic resonance imaging (MRI) was performed in 20 patients in this prospective study. The MR study included 3 separate DWI sequences: FB-DWI, SMS-DWI, and PACE-DWI. The image quality, mean ADC, standard deviations (SD) of ADC, and ADC histogram were compared. Wilcoxon signed-rank tests were used to compare qualitative image quality. A linear mixed model was used to compare the mean ADC and the SDs of the ADC values. All tests were 2-sided and P values of < 0.05 were considered statistically significant.

RESULTS

There were 56 lesions (50 malignant) evaluated in this study. The mean qualitative image quality score of PACE-DWI was 4.48. This was significantly better than that of SMS-DWI (4.22) and FB-DWI (3.15) (P < 0.05). Quantitatively, the mean ADC values from the 3 different sequences did not significantly differ for each liver lesion. FB-DWI had a markedly higher variation in the SD of the ADC values than did SMS-DWI and PACE-DWI. We found statistically significant differences in the SDs of the ADC values for FB-DWI vs PACE-DWI (P < 0.0001) and for FB-DWI vs SMS-DWI (P = 0.03). The SD of the ADC values was not statistically significant for PACE-DWI and SMS-DWI (P = 0.18). The quality of the PACE-DWI ADC histograms were considered better than the SMS-DWI and FB-DWI.

CONCLUSION

Compared to FB-DWI, both PACE-DWI and SMS-DWI provide better image quality and decreased quantitative variability in the measurement of ADC values of liver lesions.

Keywords: Diffusion; Magnetic resonance imaging; Liver; Apparent diffusion coefficient; Prospective acquisition correction; Multi-slice

Core tip: We compared 3 diffusion-weighted imaging (DWI) techniques for liver imaging: The free-breathing (FB), simultaneous multi-slice (SMS) and prospective acquisition correction (PACE) sequences. Three radiologists independently scored the images. We evaluated the image quality. We also compare the calculated apparent diffusion coefficient (ADC) for liver lesions and variability of ADC histogram for liver lesions for each sequence. The PACE and SMS provide better image quality and less variability in ADC values compared to FB-DWI.