Retrospective Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 7, 2020; 26(33): 4996-5007
Published online Sep 7, 2020. doi: 10.3748/wjg.v26.i33.4996
Liver fat accumulation measured by high-speed T2-corrected multi-echo magnetic resonance spectroscopy can predict risk of cholelithiasis
Hong Chen, Wei-Ke Zeng, Guang-Zi Shi, Ming Gao, Meng-Zhu Wang, Jun Shen
Hong Chen, Wei-Ke Zeng, Guang-Zi Shi, Ming Gao, Jun Shen, Department of Radiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, Guangdong Province, China
Meng-Zhu Wang, Department of MR Scientific Marketing, Siemens Healthineers, Guangzhou 510120, Guangdong Province, China
Author contributions: Chen H and Zeng WK contributed equally to this work; Chen H and Shen J designed the research; Chen H, Zeng WK, Shi GZ, and Wang MZ collected and analyzed the data; Chen H wrote the manuscript; Chen H, Zeng WK, Shi GZ, Gao M, and Wang MZ analyzed and interpreted the data; Shen J wrote and revised the manuscript; all co-authors participated in writing and checking the manuscript, and approved the submitted manuscript.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of Sun Yat-Sen Memorial Hospital.
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: The authors declare no conflict of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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: Jun Shen, MD, Doctor, Professor, Department of Radiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 107 West Yanjiang Road, Guangzhou 510120, Guangdong Province, China. shenjun@mail.sysu.edu.cn
Received: May 29, 2020
Peer-review started: May 29, 2020
First decision: June 12, 2020
Revised: June 14, 2020
Accepted: August 1, 2020
Article in press: August 1, 2020
Published online: September 7, 2020
Processing time: 97 Days and 14.4 Hours
ARTICLE HIGHLIGHTS
Research background

Cholelithiasis is one of the most common and substantial health problems of the digestive system worldwide. Liver biopsy is the gold standard for evaluating liver fat accumulation, however, biopsy is an invasive procedure limited by sampling bias and variability among observers and intra-observers. Computed tomography (CT) and ultrasonography have been previously used to detect liver steatosis. However, both CT and ultrasonography have limited accuracy. Advanced magnetic resonance spectroscopy (MRS) has been shown to be a robust method for quantifying liver fat and iron accumulation. Whether liver fat and iron content as assessed by multi-echo MRS are predictive of cholelithiasis remains to be determined.

Research motivation

The increase in total cholesterol synthesis can cause tissues to be overloaded with fatty acids, resulting in more lithogenic bile due to overproduction of hepatic cholesterol. The multi-echo single-voxel stimulated echo acquisition mode (STEAM) spectroscopy sequence minimizes the influence of T1 relaxation and corrects the T2 effect of different echo times, and can achieve satisfactory quantification of liver fat and iron, which may be helpful to diagnosis mild liver steatosis in patients with cholelithiasis.

Research objectives

To investigate whether liver fat accumulation measured by high-speed T2-corrected multi-echo MRS is a risk factor for cholelithiasis. The findings obtained can provide information for predicting the risk of cholelithiasis by using MRS.

Research methods

This study retrospectively enrolled 40 patients with cholelithiasis (mean age: 54.8 ± 14.6 years) and 31 healthy controls (mean age: 50.6 ± 14.3 years) who underwent high-speed T2-corrected multi-echo single-voxel MRS. Magnetic resonance imaging was performed on a 3T MR scanner (MAGNETOM Skyra; Siemens Healthcare, Erlangen, Germany). The proton density fat fraction (PDFF), R2 value, and waist circumference (WC) were calculated. Spearman’s correlation analysis was used to analyze the relationship between PDFF, R2 and WC values. Significant predictors of the risk of cholelithiasis were determined by multivariate logistic regression analysis. Receiver operating characteristic curve analysis was used to evaluate the discriminative performance of significant predictors.

Research results

Patients with cholelithiasis had higher PDFF (5.8% ± 4.2% vs 3.3% ± 2.4%, P = 0.001), R2 value (50.4 ± 24.8/s vs 38.3 ± 8.8/s, P = 0.034), and WC value (85.3 ± 9.0 cm vs 81.0 ± 6.9 cm, P = 0.030) compared with healthy controls. PDFF was positively correlated with WC (r = 0.502, P < 0.001) and R2 (r = 0.425, P < 0.001). Only PDFF was an independent risk factor for cholelithiasis (P = 0.003, OR: 1.79, 95%CI: 1.22-2.62), and the area under the curve of PDFF was 0.723 for discriminating cholelithiasis from healthy controls at the cut-off value of PDFF was 4.4%. However, due to the relatively small sample size, a large population from multiple centers is needed for further validation of our findings.

Research conclusions

PDFF measured by high speed T2-corrected multi-echo MRS is associated with cholelithiasis. MRS can be used as a quantitative tool to simultaneously monitor the liver fat content and hepatic iron overload.

Research perspectives

This study describes that PDFF derived from high speed T2-corrected multi-echo MRS can predict the risk of cholelithiasis. MRS can quantitatively detect liver steatosis in a simple breath-hold of 15s, which holds a good potential for clinical application.