1
|
Li YW, Jiao Y, Chen N, Gao Q, Chen YK, Zhang YF, Wen QP, Zhang ZM. How to select the quantitative magnetic resonance technique for subjects with fatty liver: A systematic review. World J Clin Cases 2022; 10:8906-8921. [PMID: 36157636 PMCID: PMC9477046 DOI: 10.12998/wjcc.v10.i25.8906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 05/25/2022] [Accepted: 07/22/2022] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Early quantitative assessment of liver fat content is essential for patients with fatty liver disease. Mounting evidence has shown that magnetic resonance (MR) technique has high accuracy in the quantitative analysis of fatty liver, and is suitable for monitoring the therapeutic effect on fatty liver. However, many packaging methods and postprocessing functions have puzzled radiologists in clinical applications. Therefore, selecting a quantitative MR imaging technique for patients with fatty liver disease remains challenging.
AIM To provide information for the proper selection of commonly used quantitative MR techniques to quantify fatty liver.
METHODS We completed a systematic literature review of quantitative MR techniques for detecting fatty liver, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. Studies were retrieved from PubMed, Embase, and Cochrane Library databases, and their quality was assessed using the Quality Assessment of Diagnostic Studies criteria. The Reference Citation Analysis database (https://www.referencecitationanalysis.com) was used to analyze citation of articles which were included in this review.
RESULTS Forty studies were included for spectroscopy, two-point Dixon imaging, and multiple-point Dixon imaging comparing liver biopsy to other imaging methods. The advantages and disadvantages of each of the three techniques and their clinical diagnostic performances were analyzed.
CONCLUSION The proton density fat fraction derived from multiple-point Dixon imaging is a noninvasive method for accurate quantitative measurement of hepatic fat content in the diagnosis and monitoring of fatty liver progression.
Collapse
Affiliation(s)
- You-Wei Li
- Department of Radiology, Beijing Rehabilitation Hospital, Capital Medical University, Beijing 100144, China
| | - Yang Jiao
- Department of Rehabilitation Psychology, Beijing Rehabilitation Hospital, Capital Medical University, Beijing 100144, China
| | - Na Chen
- Department of Otorhinolaryngology, Beijing Rehabilitation Hospital, Capital Medical University, Beijing 100144, China
| | - Qiang Gao
- Department of Gastroenterology and Hepatology, Beijing Rehabilitation Hospital, Capital Medical University, Beijing 100144, China
| | - Yu-Kun Chen
- Department of Radiology, Beijing Rehabilitation Hospital, Capital Medical University, Beijing 100144, China
| | - Yuan-Fang Zhang
- Department of Radiology, Beijing Rehabilitation Hospital, Capital Medical University, Beijing 100144, China
| | - Qi-Ping Wen
- Department of Radiology, Beijing Rehabilitation Hospital, Capital Medical University, Beijing 100144, China
| | - Zong-Ming Zhang
- Department of General Surgery, Beijing Electric Power Hospital, State Grid Corporation of China, Capital Medical University, Beijing 100073, China
| |
Collapse
|
2
|
Zhang G, Wang X, Chung TY, Ye W, Hodge L, Zhang L, Chng K, Xiao YF, Wang YJ. Carbon tetrachloride (CCl 4) accelerated development of non-alcoholic fatty liver disease (NAFLD)/steatohepatitis (NASH) in MS-NASH mice fed western diet supplemented with fructose (WDF). BMC Gastroenterol 2020; 20:339. [PMID: 33059584 PMCID: PMC7560288 DOI: 10.1186/s12876-020-01467-w] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 09/23/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Multiple murine models of nonalcoholic fatty liver disease/steatohepatitis (NAFLD/NASH) have been established by using obesogenic diets and/or chemical induction. MS-NASH mouse (formally FATZO) is a spontaneously developed dysmetabolic strain that can progress from hepatosteatosis to moderate fibrosis when fed a western diet supplemented with 5% fructose (WDF). This study aimed to use carbon tetrachloride (CCl4) to accelerate and aggravate progression of NAFLD/NASH in MS-NASH mouse. METHODS Male MS-NASH mice at 8 weeks of age were fed WDF for the entire study. Starting at 16 weeks of age, CCl4 was intraperitoneally administered twice weekly at a dose of 0.2 mL/kg for 3 weeks or 0.08 mL/kg for 8 weeks. Obeticholic acid (OCA, 30 mg/kg, QD) was administered in both MS-NASH and C57Bl/6 mice fed WDF and treated with CCl4 (0.08 mL/kg). RESULTS WDF enhanced obesity and hepatosteatosis, as well as induced moderate fibrosis in MS-NASH mice similar to previous reports. Administration of CCl4 accelerated liver fibrosis with increased bridging and liver hydroxyproline contents, but had no significant impact on liver steatosis and lipid contents. High dose CCl4 caused high mortality and dramatic elevation of ALT and ASL, while low dose CCl4 resulted in a moderate elevation of ALT and AST with low mortality. Compared to C57BI/6 mice with WDF and CCl4 (0.08 mL/kg), MS-NASH mice had more prominent hepatosteatosis and fibrosis. OCA treatment significantly lowered liver triglycerides, steatosis and fibrosis in both MS-NASH and C57Bl/6 mice fed WDF with CCl4 treatment. CONCLUSIONS CCl4 reduced induction time and exacerbated liver fibrosis in MS-NASH mice on WDF, proving a superior NASH model with more prominent liver pathology, which has been used favorably in pharmaceutical industry for testing novel NASH therapeutics.
Collapse
Affiliation(s)
| | | | | | - Weiwei Ye
- Crown Bioscience (CBTC), Taicang, China
| | - Lauren Hodge
- Crown Bioscience (CBLA), New Iberia, Louisiana, USA
| | | | - Keefe Chng
- Crown Bioscience (CBLA), New Iberia, Louisiana, USA
| | | | - Yixin Jim Wang
- Crown Bioscience (CBLA), New Iberia, Louisiana, USA.
- Crown Bioscience (CBTC), Taicang, China.
| |
Collapse
|
3
|
Hari A, Fealy CE, Axelrod CL, Haus JM, Flask CA, McCullough AJ, Kirwan JP. Exercise Training Rapidly Increases Hepatic Insulin Extraction in NAFLD. Med Sci Sports Exerc 2020; 52:1449-1455. [PMID: 32028458 DOI: 10.1249/mss.0000000000002273] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
PURPOSE We aimed to determine the immediacy of exercise intervention on liver-specific metabolic processes in nonalcoholic fatty liver disease. METHODS We undertook a short-term (7-d) exercise training study (60 min·d treadmill walking at 80%-85% of maximal heart rate) in obese adults (N = 13, 58 ± 3 yr, 34.3 ± 1.1 kg·m, >5% hepatic lipid by H-magnetic resonance spectroscopy). Insulin sensitivity index was estimated by oral glucose tolerance test using the Soonthorpun model. Hepatic insulin extraction (HIE) was calculated as the molar difference in area under the curve (AUC) for insulin and C-peptide (HIE = 1 - (AUCInsulin/AUCC-Pep)). RESULTS The increases in HIE, V˙O2max, and insulin sensitivity index after the intervention were 9.8%, 9.8%, and 34%, respectively (all, P < 0.05). Basal fat oxidation increased (pre: 47 ± 6 mg·min vs post: 65 ± 6 mg·min, P < 0.05) and carbohydrate oxidation decreased (pre: 160 ± 20 mg·min vs post: 112 ± 15 mg·min, P < 0.05) with exercise training. After the intervention, HIE correlated positively with adiponectin (r = 0.56, P < 0.05) and negatively with TNF-α (r = -0.78, P < 0.001). CONCLUSIONS By increasing HIE along with peripheral insulin sensitivity, aerobic exercise training rapidly reverses some of the underlying physiological mechanisms associated with nonalcoholic fatty liver disease, in a weight loss-independent manner. This reversal could potentially act through adipokine-related pathways.
Collapse
Affiliation(s)
| | - Ciaràn E Fealy
- Nutrition and Movement Sciences, Maastricht University, Maastricht, The NETHERLANDS
| | - Christopher L Axelrod
- Integrated Physiology and Molecular Medicine Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA
| | - Jacob M Haus
- Human Bioenergetics Laboratory, University of Michigan, Ann Arbor, MI
| | | | - Arthur J McCullough
- Department of Gastroenterology and Hepatology, Cleveland Clinic, Cleveland, OH
| | | |
Collapse
|
4
|
Chikui T, Yamashita Y, Kise Y, Saito T, Okamura K, Yoshiura K. Estimation of proton density fat fraction of the salivary gland. Br J Radiol 2018; 91:20170671. [PMID: 29376736 DOI: 10.1259/bjr.20170671] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
OBJECTIVE Our first objective was to prove the validity of the six-point Dixon method for estimating the proton density fat fraction (PDFF) of the salivary gland. The second objective was to estimate the salivary gland PDFF using Dixon method to evaluate the pathological conditions. METHODS At first, 12 volunteers underwent two types of sequences: single-voxel magnetic resonance spectroscopy and the Dixon method and the PDFFs obtained by the two methods were compared. Next, a total of 67 individuals [normal, n = 46; Sjögren's syndrome (SS), n = 11; and IgG4-related dacryoadenitis and sialadenitis (IgG4-DS), n = 4, parotitis, n = 6] were enrolled to estimate the parotid gland (PG) and submandibular gland (SMG) PDFF using the Dixon method. RESULTS This volunteer study demonstrated excellent correlation between two methods (R2 = 0.964, slope = 1.05). In the normal group, the PG-PDFF was correlated with the weight and body mass index (BMI) (ρ = 0.38, p = 0.0085; and ρ = 0.63, p < 0.0001). The SMG-PDFF was also correlated with the weight, BMI, and serum triglyceride (ρ = 0.37, p = 0.0067; ρ = 0.42, p = 0.0022; and ρ = 0.35, p = 0.024). The PG-PDFF of the SS group (48.2 ± 15.1%) was higher than that of any other groups; however, no significant difference was found due to the wide overlap. The SS group (39.0 ± 26.14%) also had significantly higher SMG-PDFF than the normal group (8.9 ± 5.4%), p < 0.0001) and IgG4-DS group (3.8 ± 2.3%), p = 0.020). CONCLUSION The Dixon method is a feasible method for estimating the PDFF and demonstrates fat accumulation in SMG in the SS group. Advances in knowledge: The PDFF obtained by the Dixon method is helpful for understanding the salivary gland pathological condition.
Collapse
Affiliation(s)
- Toru Chikui
- 1 Department of Oral and Maxillofacial Radiology, Faculty of Dental Science, Kyushu University , Fukuoka , Japan
| | - Yasuo Yamashita
- 2 Department of Medical Technology, Kyushu University Hospital , Fukuoka , Japan
| | - Yoshitaka Kise
- 3 Department of Oral and Maxillofacial Radiology, School of Dentistry, Aichi Gakuin University , Nagoya , Japan
| | - Tomonori Saito
- 2 Department of Medical Technology, Kyushu University Hospital , Fukuoka , Japan
| | - Kazutoshi Okamura
- 1 Department of Oral and Maxillofacial Radiology, Faculty of Dental Science, Kyushu University , Fukuoka , Japan
| | - Kazunori Yoshiura
- 1 Department of Oral and Maxillofacial Radiology, Faculty of Dental Science, Kyushu University , Fukuoka , Japan
| |
Collapse
|
5
|
Cheng X, Blake GM, Brown JK, Guo Z, Zhou J, Wang F, Yang L, Wang X, Xu L. The measurement of liver fat from single-energy quantitative computed tomography scans. Quant Imaging Med Surg 2017; 7:281-291. [PMID: 28811994 DOI: 10.21037/qims.2017.05.06] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND Studies of soft tissue composition using computed tomography (CT) scans are often semi-quantitative and based on Hounsfield units (HU) measurements that have not been calibrated with a quantitative CT (QCT) phantom. We describe a study to establish the water (H2O) and dipotassium hydrogen phosphate (K2HPO4) basis set equivalent densities of fat and fat-free liver tissue. With this information liver fat can be accurately measured from any abdominal CT scan calibrated with a suitable phantom. METHODS Liver fat content was measured by comparing single-energy QCT (SEQCT) HU measurements of the liver with predicted HU values for fat and fat-free liver tissue calculated from their H2O and K2HPO4 equivalent densities and calibration data from a QCT phantom. The equivalent densities of fat were derived from a listing of its constituent fatty acids, and those of fat-free liver tissue from a dual-energy QCT (DEQCT) study performed in 14 healthy Chinese subjects. This information was used to calculate liver fat from abdominal SEQCT scans performed in a further 541 healthy Chinese subjects (mean age 62 years; range, 31-95 years) enrolled in the Prospective Urban Rural Epidemiology (PURE) Study. RESULTS The equivalent densities of fat were 941.75 mg/cm3 H2O and -43.72 mg/cm3 K2HPO4, and for fat-free liver tissue 1,040.13 mg/cm3 H2O and 21.34 mg/cm3 K2HPO4. Liver fat in the 14 subjects in the DEQCT study varied from 0-17.9% [median: 4.5%; interquartile range (IQR): 3.0-7.9%]. Liver fat in the 541 PURE study subjects varied from -0.3-29.9% (median: 4.9%; IQR: 3.4-6.9%). CONCLUSIONS We have established H2O and K2HPO4 equivalent densities for fat and fat-free liver tissue that allow a measurement of liver fat to be obtained from any abdominal CT scan acquired with a QCT phantom. Although radiation dose considerations preclude the routine use of QCT to measure liver fat, the method described here facilitates its measurement in patients having CT scans performed for other purposes. Further studies comparing the results with magnetic resonance (MR) measurements of liver fat are required to validate the method as a useful clinical tool.
Collapse
Affiliation(s)
- Xiaoguang Cheng
- Department of Radiology, Beijing Jishuitan Hospital, Beijing 100035, China
| | - Glen M Blake
- Biomedical Engineering Department, King's College London, Strand, London WC2R 2LS, UK
| | | | - Zhe Guo
- Department of Radiology, Beijing Jishuitan Hospital, Beijing 100035, China
| | - Jun Zhou
- Department of Radiology, Shenyang No.4 Hospital, Shenyang 110082, China
| | - Fengzhe Wang
- Department of Radiology, Shenyang No.4 Hospital, Shenyang 110082, China
| | - Liqiang Yang
- Department of Radiology, the General Hospital of CNPC in Jilin City, Jilin 132021, China
| | - Xiaohong Wang
- Department of Radiology, the General Hospital of CNPC in Jilin City, Jilin 132021, China
| | - Li Xu
- Department of Radiology, Beijing Jishuitan Hospital, Beijing 100035, China
| |
Collapse
|
6
|
Forbes S, Barr SM, Reynolds RM, Semple S, Gray C, Andrew R, Denison FC, Walker BR, Norman JE. Convergence in insulin resistance between very severely obese and lean women at the end of pregnancy. Diabetologia 2015; 58:2615-26. [PMID: 26248646 PMCID: PMC4589551 DOI: 10.1007/s00125-015-3708-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 07/03/2015] [Indexed: 11/29/2022]
Abstract
AIMS Disrupted intermediary metabolism may contribute to the adverse pregnancy outcomes in women with very severe obesity. Our aim was to study metabolism in such pregnancies. METHODS We recruited a longitudinal cohort of very severely obese (n = 190) and lean (n = 118) glucose-tolerant women for anthropometric and metabolic measurements at early, mid and late gestation and postpartum. In case-control studies of very severely obese and lean women we measured glucose and glycerol turnover during low- and high-dose hyperinsulinaemic-euglycaemic clamps (HEC) at early and late pregnancy and in non-pregnant women (each n = 6-9) and body fat distribution by MRI in late pregnancy (n = 10/group). RESULTS Although greater glucose, insulin, NEFA and insulin resistance (HOMA-IR), and greater weight and % fat mass (FM) was observed in very severely obese vs lean participants, the degree of worsening was attenuated in the very severely obese individuals with advancing gestation, with no difference in triacylglycerol (TG) concentrations between very severely obese and lean women at term. Enhanced glycerol production was observed in early pregnancy only in very severely obese individuals, with similar intrahepatic FM in very severely obese vs lean women by late gestation. Offspring from obese mothers were heavier (p = 0.04). CONCLUSIONS/INTERPRETATION Pregnancies complicated by obesity demonstrate attenuation in weight gain and insulin resistance compared with pregnancies in lean women. Increased glycerol production is confined to obese women in early pregnancy and obese and lean individuals have similar intrahepatic FM by term. When targeting maternal metabolism to treat adverse pregnancy outcomes, therapeutic intervention may be most effective applied early in pregnancy.
Collapse
Affiliation(s)
- Shareen Forbes
- Tommy's Centre for Fetal and Maternal Health, MRC Centre for Reproductive Health, University of Edinburgh, Queen's Medical Research Institute, Edinburgh, UK.
- Endocrinology Unit, University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK.
| | - Sarah M Barr
- Tommy's Centre for Fetal and Maternal Health, MRC Centre for Reproductive Health, University of Edinburgh, Queen's Medical Research Institute, Edinburgh, UK
| | - Rebecca M Reynolds
- Tommy's Centre for Fetal and Maternal Health, MRC Centre for Reproductive Health, University of Edinburgh, Queen's Medical Research Institute, Edinburgh, UK
- Endocrinology Unit, University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Scott Semple
- Clinical Research Imaging Centre, University of Edinburgh, Queen's Medical Research Institute, Edinburgh, UK
| | - Calum Gray
- Clinical Research Imaging Centre, University of Edinburgh, Queen's Medical Research Institute, Edinburgh, UK
| | - Ruth Andrew
- Endocrinology Unit, University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Fiona C Denison
- Tommy's Centre for Fetal and Maternal Health, MRC Centre for Reproductive Health, University of Edinburgh, Queen's Medical Research Institute, Edinburgh, UK
| | - Brian R Walker
- Endocrinology Unit, University/BHF Centre for Cardiovascular Science, University of Edinburgh, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Jane E Norman
- Tommy's Centre for Fetal and Maternal Health, MRC Centre for Reproductive Health, University of Edinburgh, Queen's Medical Research Institute, Edinburgh, UK
| |
Collapse
|
7
|
AlKhater SA. Paediatric non-alcoholic fatty liver disease: an overview. Obes Rev 2015; 16:393-405. [PMID: 25753407 DOI: 10.1111/obr.12271] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Revised: 01/17/2015] [Accepted: 01/28/2015] [Indexed: 12/12/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a progressive disease that encompasses a spectrum of liver diseases, ranging from simple steatosis to non-alcoholic steatohepatitis (NASH). Data related to survival in children are scarce, but these data firmly associate NAFLD with higher risks of hepatic and non-hepatic morbidities and mortalities compared with the general population. More recently, the association between NAFLD and cardiovascular disease among children has increasingly been recognized. Given that obesity is a major risk factor for the disease, paediatric NAFLD is becoming a global issue, paralleling the dramatic rise in obesity worldwide. NASH, which is more common in obese children, has the potential to advance to liver fibrosis and failure. It is unclear why certain patients undergo such transformation but this susceptibility is likely related to an interaction between a genetically susceptible host and the surrounding environment. Currently, treatment is largely conservative and includes lifestyle modification, attainable through healthy weight reduction via diet and exercise. In this review, current knowledge about NAFLD in children is summarized. This review aims to increase the awareness of the medical community about a hidden public health issue and to identify current gaps in the literature while providing directions for future research.
Collapse
Affiliation(s)
- S A AlKhater
- Department of Pediatric, Dammam University, Dammam, Saudi Arabia
| |
Collapse
|
8
|
Pokhrel B, Choi EK, Khalid O, Sandrasegaran K, Fogel EL, McHenry L, Sherman S, Watkins J, Cote GA, Pitt HA, Zyromski NJ, Juliar B, Lehman GA. Increased fat in pancreas not associated with risk of pancreatitis post-endoscopic retrograde cholangiopancreatography. Clin Exp Gastroenterol 2014; 7:199-204. [PMID: 24959090 PMCID: PMC4061141 DOI: 10.2147/ceg.s31333] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Background A preliminary study has shown increased pancreatic fat in patients with idiopathic pancreatitis and sphincter of Oddi dysfunction. In this study, we aimed to determine if an increased quantity of pancreatic fat is an independent risk factor for pancreatitis post-endoscopic retrograde cholangiopancreatography (ERCP). Methods In this case control study, we retrospectively reviewed a local radiological and ERCP database to identify patients who had had abdominal magnetic resonance imaging (MRI) followed by ERCP no more than 60 days later between September 2003 and January 2011. Percentage of fat was determined by recording signal intensity in the in-phase (Sin) and out-of-phase (Sout) T1-weighted gradient sequences, and calculation of the fat fraction as (Sin − Sout)/(Sin) × 2 by an abdominal radiologist blinded to clinical history. Controls matched for age, gender, and other pancreatobiliary disease were selected from a group with no post-ERCP pancreatitis (before fat content of the pancreas was analyzed). Results Forty-seven patients were enrolled. Compared with controls, subjects with post-ERCP pancreatitis were similar in terms of age (41.4 years versus 41.1 years), gender (21.2% versus 20.2% males), pancreatobiliary disease characteristics, and most ERCP techniques. Measurements of pancreatic head, body, and tail fat and body mass index were similar in patients and controls. Conclusion Increased pancreatic fat on MRI criteria is not an independent predictor of post-ERCP pancreatitis.
Collapse
Affiliation(s)
- Bhupesh Pokhrel
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Eun Kwang Choi
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Omer Khalid
- Department of Gastroenterology, St Louis University School of Medicine, St Louis, MO
| | - Kumar Sandrasegaran
- Department of Radiology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Evan L Fogel
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Lee McHenry
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Stuart Sherman
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - James Watkins
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Gregory A Cote
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Henry A Pitt
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Nicholas J Zyromski
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Beth Juliar
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Glen A Lehman
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| |
Collapse
|
9
|
Dijkstra H, Handayani A, Kappert P, Oudkerk M, Sijens PE. Clinical implications of non-steatotic hepatic fat fractions on quantitative diffusion-weighted imaging of the liver. PLoS One 2014; 9:e87926. [PMID: 24505333 PMCID: PMC3913701 DOI: 10.1371/journal.pone.0087926] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 01/01/2014] [Indexed: 01/27/2023] Open
Abstract
Diffusion-weighted imaging (DWI) is an important diagnostic tool in the assessment of focal liver lesions and diffuse liver diseases such as cirrhosis and fibrosis. Quantitative DWI parameters such as molecular diffusion, microperfusion and their fractions, are known to be affected when hepatic fat fractions (HFF) are higher than 5.5% (steatosis). However, less is known about the effect on DWI for HFF in the normal non-steatotic range below 5.5%, which can be found in a large part of the population. The aim of this study was therefore to evaluate the diagnostic implications of non-steatotic HFF on quantitative DWI parameters in eight liver segments. For this purpose, eleven healthy volunteers (2 men, mean-age 31.0) were prospectively examined with DWI and three series of in-/out-of-phase dual-echo spoiled gradient-recalled MRI sequences to obtain the HFF and T2*. DWI data were analyzed using the intravoxel incoherent motion (IVIM) model. Four circular regions (ø22.3 mm) were drawn in each of eight liver segments and averaged. Measurements were divided in group 1 (HFF≤2.75%), group 2 (2.75< HFF ≤5.5%) and group 3 (HFF>5.5%). DWI parameters and T2* were compared between the three groups and between the segments. It was observed that the molecular diffusion (0.85, 0.72 and 0.49 ×10−3 mm2/s) and T2* (32.2, 27.2 and 21.0 ms) differed significantly between the three groups of increasing HFF (2.18, 3.50 and 19.91%). Microperfusion and its fraction remained similar for different HFF. Correlations with HFF were observed for the molecular diffusion (r = −0.514, p<0.001) and T2* (−0.714, p<0.001). Similar results were obtained for the majority of individual liver segments. It was concluded that fat significantly decreases molecular diffusion in the liver, also in absence of steatosis (HFF≤5.5%). Also, it was confirmed that fat influences T2*. Determination of HFF prior to quantitative DWI is therefore crucial.
Collapse
Affiliation(s)
- Hildebrand Dijkstra
- Center for Medical Imaging - North East Netherlands, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- * E-mail:
| | - Astri Handayani
- Center for Medical Imaging - North East Netherlands, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Peter Kappert
- Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Matthijs Oudkerk
- Center for Medical Imaging - North East Netherlands, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Paul E. Sijens
- Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| |
Collapse
|
10
|
Abstract
Magnetic resonance of the body offers different techniques for mapping fat deposits (MR Imaging) and analysis of organs with small amounts of lipids (MR Spectroscopy). Possible approaches for whole-body assessment of adipose tissue are presented and discussed and spectroscopic examinations in different organs are depicted. With magnetic resonance imaging (MRI) it has been shown that obesity per se is not a marker for metabolic failure, but depends on regional variations of body composition and ectopic lipid accumulation. In addition MRI of the brain is a powerful research tool to understand the brain's role in the development and maintenance of obesity and the overconsumption of foods in obese individuals. Sonography has a low accuracy in estimating hepatic steatosis until now. New sonographic methods have been evaluated to detect hepatic steatosis by physical properties of fatty tissue as tissue stiffness, sound absorption or sound speed. Nuclear medicine and in particular Positron Emission Tomography (PET) methods are used to explore central pathophysiology, brown adipose tissue activity and alterations in homeostatic feedback and gut-brain communication.
Collapse
Affiliation(s)
- Jürgen Machann
- Institute for Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the University of Tübingen (Paul Langerhans Institute Tübingen), Tübingen, Germany.
| | | | | | | | | |
Collapse
|
11
|
de Souza DAT, Parente DB, de Araújo ALE, Mortelé KJ. Modern imaging evaluation of the liver: emerging MR imaging techniques and indications. Magn Reson Imaging Clin N Am 2013; 21:337-63. [PMID: 23642557 DOI: 10.1016/j.mric.2013.01.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Modern MR imaging evaluation of the liver allows for a comprehensive morphologic and functional assessment of the liver parenchyma, hepatic vessels, and biliary tree, thus aiding in the diagnosis of both focal and diffuse liver diseases.
Collapse
|
12
|
Hayashi N, Miyati T, Minami T, Takeshita Y, Ryu Y, Matsuda T, Ohno N, Hamaguchi T, Kato K, Takamura T, Matsui O. Quantitative analysis of hepatic fat fraction by single-breath-holding MR spectroscopy with T₂ correction: phantom and clinical study with histologic assessment. Radiol Phys Technol 2012; 6:219-25. [PMID: 23224694 DOI: 10.1007/s12194-012-0191-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Revised: 11/22/2012] [Accepted: 11/22/2012] [Indexed: 12/13/2022]
Abstract
The focus of this study was on the investigation of the accuracy of the fat fraction of the liver by use of single-breath-holding magnetic resonance spectroscopy (MRS) with T (2) correction. Single-voxel proton MRS was performed with several TE values, and the fat fraction was determined with and without T (2) correction. MRS was also performed with use of the point-resolved spectroscopy sequence in single breath holding. The T (2) values of both water and fat were determined separately at the same time, and the effect of T (2) on the fat fraction was corrected. In addition, MRS-based fat fractions were compared with the degree of hepatic steatosis (HS) by liver biopsy in human subjects. With T (2) correction, the MRI-derived fat fractions were in good agreement with the fat fractions in all phantoms, but the fat fractions were overestimated without T (2) correction. R (2) values were in good agreement with the preset iron concentrations in the phantoms. The MRI-derived fat fraction was well correlated with the degree of HS. Iron deposited in the liver affects the signal strength when proton MRS is used for detection of the fat signal in the liver. However, the fat signal can be evaluated more accurately when the T (2) correction is applied. Breath-holding MRS minimizes the respiratory motion, and it can be more accurate in the quantification of the hepatic fat fraction.
Collapse
Affiliation(s)
- Norio Hayashi
- School of Radiological Technology, Gunma Prefectural College of Health Sciences, 323-1 Kamioki, Maebashi, Gunma 371-0052, Japan.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Fealy CE, Haus JM, Solomon TPJ, Pagadala M, Flask CA, McCullough AJ, Kirwan JP. Short-term exercise reduces markers of hepatocyte apoptosis in nonalcoholic fatty liver disease. J Appl Physiol (1985) 2012; 113:1-6. [PMID: 22582214 DOI: 10.1152/japplphysiol.00127.2012] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Increased hepatocyte apoptosis is a hallmark of nonalcoholic fatty liver disease (NAFLD) and contributes to the profibrogenic state responsible for the progression to nonalcoholic steatohepatitis (NASH). Strategies aimed at reducing apoptosis may result in better outcomes for individuals with NAFLD. We therefore examined the effect of a short-term exercise program on markers of apoptosis-plasma cytokeratin 18 (CK18) fragments, alanine aminotransferase (ALT), aspartate aminotransferase (AST), soluble Fas (sFas), and sFas ligand (sFasL)-in 13 obese individuals with NAFLD [body mass index 35.2 ± 1.2 kg/m(2), >5% intrahepatic lipid (IHL) assessed by (1)H-MR spectroscopy]. Exercise consisted of treadmill walking for 60 min/day on 7 consecutive days at ∼85% of maximal heart rate. Additionally, subjects underwent an oral glucose tolerance test and a maximal oxygen consumption (Vo(2max)) test before and after the exercise intervention. The Matsuda index was used to assess insulin sensitivity. We observed significant decreases in CK18 fragments (558.4 ± 106.8 vs. 323.4 ± 72.5 U/l, P < 0.01) and ALT (30.2 ± 5.1 vs. 24.3 ± 4.8 U/l, P < 0.05), and an increase in whole body fat oxidation (49.3 ± 6.1 vs. 69.4 ± 7.1 mg/min, P < 0.05), while decreases in circulating sFasL approached statistical significance (66.5 ± 6.0 vs. 63.0 ± 5.7 pg/ml, P = 0.06), as did the relationship between percent change in circulating CK18 fragments and ALT (r = 0.55, P = 0.05). We also observed a significant correlation between changes in fat oxidation and circulating sFasL (rho = -0.65, P < 0.05). There was no change in IHL following the intervention (18.2 ± 2.5 vs. 17.5 ± 2.1%, NS). We conclude that short-term exercise reduces a circulatory marker of hepatocyte apoptosis in obese individuals with NAFLD and propose that changes in the proapoptotic environment may be mediated through improved insulin sensitivity and increased oxidative capacity.
Collapse
Affiliation(s)
- Ciaran E Fealy
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | | | | | | | | | | | | |
Collapse
|
14
|
Capitan V, Petit JM, Aho S, Lefevre PH, Favelier S, Loffroy R, Hillon P, Krausé D, Cercueil JP, Guiu B. Macroscopic heterogeneity of liver fat: an MR-based study in type-2 diabetic patients. Eur Radiol 2012; 22:2161-8. [DOI: 10.1007/s00330-012-2468-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 03/05/2012] [Accepted: 03/17/2012] [Indexed: 01/29/2023]
|
15
|
Abstract
OBJECTIVE A review of the peri-operative risk associated with hepatic resection in patients with metabolic syndrome (MetS) and identification of measures for the improvement of cardiometabolic disturbances and liver-related mortality. BACKGROUND MetS and its hepatic manifestation non-alcoholic fatty liver disease (NAFLD) are associated with an increased operative mortality in spite of a significant improvement in peri-operative outcome after hepatic resection. METHODS A review of the English literature on MetS, liver resection and steatosis was performed from 1980 to 2011 using the MEDLINE and PubMed databases. RESULTS MetS is a predictor of NAFLD and patients with multiple metabolic risk factors may harbour non-alcoholic steatohepatitis (NASH) predictive of operative and cardiovascular mortality. Pre-operative diagnosis of unsuspected NASH with the selective use of a liver biopsy can modify the operative strategy by limiting the extent of hepatic resection, avoiding or altering the pre-operative chemotherapy regimen and the utilization of portal vein embolization. Thiazolidinediones are therapeutic for MetS and NASH and Vitamin E for active NASH; however, their utility in improving the peri-operative outcome after hepatic resection is unknown. A short-term regimen for weight loss improves post-operative patient and liver-related outcomes in patients with >30% steatosis. Cardiovascular disease associated with MetS or NAFLD should be managed aggressively. Peri-operative measures to minimize thrombotic events and acute renal injury secondary to the pro-inflammatory, prothrombotic state of MetS may further improve the outcome. CONCLUSION Potential candidates for hepatic resection should be screened for MetS as the pre-operative identification of NASH, short-term treatment of significant steatosis, cardiovascular risk assessment and optimization of each component of MetS may improve the peri-operative outcome in this high-risk subset of patients.
Collapse
Affiliation(s)
- Shefali Agrawal
- Hepatobiliary and Pancreatic Surgery, Department of Gastrointestinal Surgery, Indraprastha Apollo HospitalsNew Delhi, India
| | - Cherag Daruwala
- Division of Gastroenterology, Department of Medicine, Temple University HospitalPhiladelphia, Pennsylvania, USA
| |
Collapse
|
16
|
|
17
|
Gaeta M, Scribano E, Mileto A, Mazziotti S, Rodolico C, Toscano A, Settineri N, Ascenti G, Blandino A. Muscle fat fraction in neuromuscular disorders: dual-echo dual-flip-angle spoiled gradient-recalled MR imaging technique for quantification--a feasibility study. Radiology 2011; 259:487-94. [PMID: 21324839 DOI: 10.1148/radiol.10101108] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE To prospectively evaluate the muscle fat fraction (MFF) measured with dual-echo dual-flip-angle spoiled gradient-recalled acquisition in the steady state (SPGR) magnetic resonance (MR) imaging technique by using muscle biopsy as the reference standard. MATERIALS AND METHODS After ethics approval, written informed consent from all patients was obtained. Twenty-seven consecutive patients, evaluated at the Neuromuscular Disorders Center with a possible diagnosis of neuromuscular disorder, were prospectively studied with MR imaging of the lower extremities to quantify muscle fatty infiltration by means of MFF calculation. Spin-density- and T1-weighted fast SPGR in-phase and opposed-phase dual-echo sequences were performed, respectively, with 20° and 80° flip angles. Round regions of interest were drawn by consensus on selected MR sections corresponding to anticipated biopsy sites. These were marked on the patient's skin with a pen by using the infrared spider light of the system, and subsequent muscle biopsy was performed. MR images with regions of interest were stored on a secondary console where the MFF calculation was performed by another radiologist blinded to the biopsy results. MFFs calculated with dual-echo dual-flip-angle SPGR MR imaging and biopsy were compared by using a paired t test, Pearson correlation coefficient, and Bland-Altman plots. P value of < .05 was considered to indicate a statistically significant difference. RESULTS The mean MFFs obtained with dual-echo dual-flip-angle SPGR MR imaging and biopsy were 20.3% (range, 1.7%-45.1%) and 20.6% (range, 3%-46.1%), respectively. The mean difference, standard deviation of the difference, and t value were -0.3, 1.3, and -1.3 (P > .2), respectively. The Pearson correlation coefficient was 0.995; with the Bland-Altman method, all data points were within the ± 2 SDs limits of agreement. CONCLUSION The results show that dual-echo dual-flip-angle SPGR MR imaging technique provides reliable calculation of MFF, consistent with biopsy measurements.
Collapse
Affiliation(s)
- Michele Gaeta
- Department of Radiological Sciences, Policlinico G. Martino, Via Consolare Valeria 1, 98125 Messina, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Meisamy S, Hines CDG, Hamilton G, Sirlin CB, McKenzie CA, Yu H, Brittain JH, Reeder SB. Quantification of hepatic steatosis with T1-independent, T2-corrected MR imaging with spectral modeling of fat: blinded comparison with MR spectroscopy. Radiology 2011; 258:767-75. [PMID: 21248233 DOI: 10.1148/radiol.10100708] [Citation(s) in RCA: 303] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
PURPOSE To prospectively compare an investigational version of a complex-based chemical shift-based fat fraction magnetic resonance (MR) imaging method with MR spectroscopy for the quantification of hepatic steatosis. MATERIALS AND METHODS This study was approved by the institutional review board and was HIPAA compliant. Written informed consent was obtained before all studies. Fifty-five patients (31 women, 24 men; age range, 24-71 years) were prospectively imaged at 1.5 T with quantitative MR imaging and single-voxel MR spectroscopy, each within a single breath hold. The effects of T2 correction, spectral modeling of fat, and magnitude fitting for eddy current correction on fat quantification with MR imaging were investigated by reconstructing fat fraction images from the same source data with different combinations of error correction. Single-voxel T2-corrected MR spectroscopy was used to measure fat fraction and served as the reference standard. All MR spectroscopy data were postprocessed at a separate institution by an MR physicist who was blinded to MR imaging results. Fat fractions measured with MR imaging and MR spectroscopy were compared statistically to determine the correlation (r(2)), and the slope and intercept as measures of agreement between MR imaging and MR spectroscopy fat fraction measurements, to determine whether MR imaging can help quantify fat, and examine the importance of T2 correction, spectral modeling of fat, and eddy current correction. Two-sided t tests (significance level, P = .05) were used to determine whether estimated slopes and intercepts were significantly different from 1.0 and 0.0, respectively. Sensitivity and specificity for the classification of clinically significant steatosis were evaluated. RESULTS Overall, there was excellent correlation between MR imaging and MR spectroscopy for all reconstruction combinations. However, agreement was only achieved when T2 correction, spectral modeling of fat, and magnitude fitting for eddy current correction were used (r(2) = 0.99; slope ± standard deviation = 1.00 ± 0.01, P = .77; intercept ± standard deviation = 0.2% ± 0.1, P = .19). CONCLUSION T1-independent chemical shift-based water-fat separation MR imaging methods can accurately quantify fat over the entire liver, by using MR spectroscopy as the reference standard, when T2 correction, spectral modeling of fat, and eddy current correction methods are used.
Collapse
Affiliation(s)
- Sina Meisamy
- Liver Imaging Research Program, Department of Radiology, University of Wisconsin, 600 Highland Ave, E3/311 CSC, Madison, WI 53792-3252, USA.
| | | | | | | | | | | | | | | |
Collapse
|
19
|
Guiu B, Petit JM, Loffroy R, Aho S, Ben Salem D, Masson D, Robin I, Vergès B, Hillon P, Cercueil JP, Krausé D. Liver methylene fraction by dual- and triple-echo gradient-echo imaging at 3.0T: Correlation with proton MR spectroscopy and estimation of robustness after SPIO administration. J Magn Reson Imaging 2010; 33:119-27. [DOI: 10.1002/jmri.22390] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
|
20
|
Assessment of relevant hepatic steatosis in obese adolescents by rapid fat-selective GRE imaging with spatial-spectral excitation: a quantitative comparison with spectroscopic findings. Eur Radiol 2010; 21:816-22. [DOI: 10.1007/s00330-010-1975-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2010] [Revised: 08/06/2010] [Accepted: 08/29/2010] [Indexed: 01/01/2023]
|
21
|
Bohte AE, van Werven JR, Bipat S, Stoker J. The diagnostic accuracy of US, CT, MRI and 1H-MRS for the evaluation of hepatic steatosis compared with liver biopsy: a meta-analysis. Eur Radiol 2010; 21:87-97. [PMID: 20680289 PMCID: PMC2995875 DOI: 10.1007/s00330-010-1905-5] [Citation(s) in RCA: 367] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 05/24/2010] [Accepted: 06/14/2010] [Indexed: 12/11/2022]
Abstract
Objective To meta-analyse the diagnostic accuracy of US, CT, MRI and 1H-MRS for the evaluation of hepatic steatosis. Methods From a comprehensive literature search in MEDLINE, EMBASE, CINAHL and Cochrane (up to November 2009), articles were selected that investigated the diagnostic performance imaging techniques for evaluating hepatic steatosis with histopathology as the reference standard. Cut-off values for the presence of steatosis on liver biopsy were subdivided into four groups: (1) >0, >2 and >5% steatosis; (2) >10, >15 and >20%; (3) >25, >30 and >33%; (4) >50, >60 and >66%. Per group, summary estimates for sensitivity and specificity were calculated. The natural-logarithm of the diagnostic odds ratio (lnDOR) was used as a single indicator of test performance. Results 46 articles were included. Mean sensitivity estimates for subgroups were 73.3–90.5% (US), 46.1–72.0% (CT), 82.0–97.4% (MRI) and 72.7–88.5% (1H-MRS). Mean specificity ranges were 69.6–85.2% (US), 88.1–94.6% (CT), 76.1–95.3% (MRI) and 92.0–95.7% (1H-MRS). Overall performance (lnDOR) of MRI and 1H-MRS was better than that for US and CT for all subgroups, with significant differences in groups 1 and 2. Conclusion MRI and 1H-MRS can be considered techniques of choice for accurate evaluation of hepatic steatosis. Electronic supplementary material The online version of this article (doi:10.1007/s00330-010-1905-5) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Anneloes E Bohte
- Department of Radiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
| | | | | | | |
Collapse
|
22
|
Marsman H, van Werven J, Nederveen A, ten Kate F, Heger M, Stoker J, van Gulik T. Noninvasive quantification of hepatic steatosis inrats using 3.0 T 1H-magnetic resonance spectroscopy. J Magn Reson Imaging 2010; 32:148-54. [DOI: 10.1002/jmri.22064] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
|
23
|
Sijens PE, Edens MA, Bakker SJL, Stolk RP. MRI-determined fat content of human liver, pancreas and kidney. World J Gastroenterol 2010; 16:1993-8. [PMID: 20419836 PMCID: PMC2860076 DOI: 10.3748/wjg.v16.i16.1993] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To assess and correlate the lipid content of various organs in obese subjects and in persons with a normal body weight.
METHODS: Magnetic resonance spectroscopy and a previously validated gradient echo magnetic resonance imaging method with Dixon’s two point technique were used in this study to quantify fat in liver, pancreas as well as kidney.
RESULTS: In 36 volunteers with body mass index (BMI) ranging from 20.0 to 42.9 kg/m2, the median fat content of liver, pancreas and kidney was 2.3% (interquartile range: 0.2%-7.8%), 2.7% (1.0%-6.5%) and 0.7% (0.1%-1.4%), respectively. BMI and subcutaneous fat correlated significantly with liver and pancreas fat content. We show for the first time the significant correlation of liver and pancreas fat content in healthy controls (r = 0.43, P < 0.01). These observations are related to body weight as measured by BMI and the amount of subcutaneous fat. Kidney fat content is very low and correlates with none of the other fat depots.
CONCLUSION: Renal lipid accumulation, unlike the coupled accumulations of fat in liver and pancreas, is not observed in obese subjects. Unlike suggestions made in previous studies, renal lipid accumulation appears not to be involved in the pathogenesis of renal disease in humans.
Collapse
|
24
|
Springer F, Machann J, Claussen CD, Schick F, Schwenzer NF. Liver fat content determined by magnetic resonance imaging and spectroscopy. World J Gastroenterol 2010; 16:1560-6. [PMID: 20355234 PMCID: PMC2848364 DOI: 10.3748/wjg.v16.i13.1560] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Hepatic steatosis as the most prevalent liver disorder can either be related to alcoholic liver disease (ALD) or non-alcoholic fatty liver disease (NAFLD). In both conditions, hepatocytes excessively accumulate fat-containing vacuoles within their cytoplasm, which is the key histological feature. In contrast to ALD, NAFLD is commonly associated with metabolic syndrome, obesity and insulin resistance. To determine increased liver fat content, liver biopsy is currently considered the gold standard. Besides the invasive technique, various other non-invasive techniques have been developed, such as ultrasound, computed tomography (CT), magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI) based methods. Among these techniques, ultrasound and CT provide only qualitative information about hepatic steatosis, whereas MRS- or MRI-based methods are able to determine even small amounts of fat accurately. These non-invasive magnetic resonance techniques have already proven their great potential, especially in longitudinal and cross-sectional studies regarding various metabolic conditions and medical treatment regimens. In this review, the most common, non-invasive MRS/MRI techniques for assessment of intrahepatic lipid content are described with their inherent advantages and limitations.
Collapse
|
25
|
Quantitative multivoxel proton chemical shift imaging of the breast. Magn Reson Imaging 2010; 28:314-9. [PMID: 20071119 DOI: 10.1016/j.mri.2009.11.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Accepted: 11/26/2009] [Indexed: 12/22/2022]
Abstract
The study of focal pathology by single-voxel magnetic resonance spectroscopy (MRS) is hampered by the impossibility to study tissue heterogeneity or compare the metabolite signals in breast lesion directly to those in unaffected tissue. Multivoxel MRS studies, while potentially allowing for truly quantitative tissue characterization, have up to now also been far from quantitative with, for example, the signal-to-noise ratio of the choline (Cho) signal serving as measure of tumor activity. Shown in this study is that in a standard clinical setting with a regular 1.5-T magnetic resonance scanner, it is possible to perform quantitative multivoxel MRS. With the use of literature values for the T1 and T2 relaxation times of Cho and water in fibroglandular breast tissue and tumors, one can determine the concentrations of Cho in different tumor compartments and surrounding tissues in two brief multivoxel MRS measurements. This opens excellent perspectives to quantitative diagnostic and follow-up studies of focal pathology such as lesions suspected of breast cancer.
Collapse
|
26
|
Edens MA, van Ooijen PMA, Post WJ, Haagmans MJF, Kristanto W, Sijens PE, van der Jagt EJ, Stolk RP. Ultrasonography to quantify hepatic fat content: validation by 1H magnetic resonance spectroscopy. Obesity (Silver Spring) 2009; 17:2239-44. [PMID: 19461588 DOI: 10.1038/oby.2009.154] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
An abundance of fat stored within the liver, or steatosis, is the beginning of a broad hepatological spectrum, usually referred to as fatty liver disease (FLD). For studies on FLD, quantitative hepatic fat ultrasonography would be an appealing study modality. Objective of this study was to develop a technique for quantifying hepatic fat content by ultrasonography and validate this using proton magnetic resonance spectroscopy ((1)H MRS) as gold standard. Eighteen white volunteers (BMI range 21.0-42.9) were scanned by both ultrasonography and (1)H MRS. Altered ultrasound characteristics, present in the case of FLD, were assessed using a specially developed software program. Various attenuation and textural based indices of FLD were extracted from ultrasound images. Using linear regression analysis, the predictive power of several models (consisting of both attenuation and textural based measures) on log 10-transformed hepatic fat content by (1)H MRS were investigated. The best quantitative model was compared with a qualitative ultrasonography method, as used in clinical care. A model with four ultrasound characteristics could modestly predict the amount of liver fat (adjusted explained variance 43.2%, P = 0.021). Expanding the model to seven ultrasound characteristics increased adjusted explained variance to 60% (P = 0.015), with r = 0.789 (P < 0.001). Comparing this quantitative model with qualitative ultrasonography revealed a significant advantage of the quantitative model in predicting hepatic fat content (P < 0.001). This validation study shows that a combination of computer-assessed ultrasound measures from routine ultrasound images can be used to quantitatively assess hepatic fat content.
Collapse
Affiliation(s)
- Mireille A Edens
- Department of Epidemiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Technique rapide de mesure de la stéatose hépatique à 3T : théorie, imagerie paramétrique, applications. ACTA ACUST UNITED AC 2009; 90:1695-702. [DOI: 10.1016/s0221-0363(09)73268-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
28
|
Zhong L, Chen JJ, Chen J, Li L, Lin ZQ, Wang WJ, Xu JR. Nonalcoholic fatty liver disease: quantitative assessment of liver fat content by computed tomography, magnetic resonance imaging and proton magnetic resonance spectroscopy. J Dig Dis 2009; 10:315-20. [PMID: 19906112 DOI: 10.1111/j.1751-2980.2009.00402.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE The purpose of this study was to evaluate the clinical application of imaging technology in the quantitative assessment of fatty liver with magnetic resonance imaging (MRI) and proton MR spectroscopy. METHODS Overall 36 patients with diffuse fatty liver who had undertaken the computed tomography (CT) scan, MRI and proton MR spectroscopy (1H MRS) were analyzed. Their body mass index (BMI) was measured and their liver to spleen CT ratio (L/S) calculated on the plain CT scan. MR T1-weighted imaging (T1WI) was obtained with in-phase (IP) and out-of-phase (OP) images. T2-weighted imaging (T2WI) was acquired with or without the fat-suppression technique. The liver fat content (LFC) was quantified as the percentage of relative signal intensity loss on T1WI or T2WI images. The intrahepatic content of lipid (IHCL) was expressed as the percentage of peak value ratio of lipid to water by 1H MRS. RESULTS The results of BMI measurement, CT L/S ratio, LFC calculated from MR T1WI and T2WI images, as well as IHCL measured by 1H MRS were 27.26 +/- 3.01 kg/m2, 0.88 +/- 0.26, 13.80 +/- 9.92%, 40.67 +/- 16.04% and 30.98 +/- 20.43%, respectively. The LFC calculated from MR T1WI, T2WI images and IHCL measured by 1H MRS correlated significantly with the CT L/S ratio (r = -0.830, P = 0.000; r = -0.736, P = 0.000; r = -0.461, P = 0.005, respectively). BMI correlated significantly only with the liver fat contents measured by T1WI IP/OP and 1H MRS (r = -0.347, P = 0.038; r = -0.374, P = 0.025, respectively). CONCLUSION CT, MR imaging and 1H MRS were effective methods for the quantitative assessment of LFC. The MR imaging, especially 1H MRS, would be used more frequently in the clinical evaluation of fatty liver and (1)H MRS could more accurately reflect the severity of fatty liver.
Collapse
Affiliation(s)
- Liang Zhong
- Department of Radiology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
| | | | | | | | | | | | | |
Collapse
|
29
|
Sijens PE. Parametric exploration of the liver by magnetic resonance methods. Eur Radiol 2009; 19:2594-607. [PMID: 19504103 PMCID: PMC2762052 DOI: 10.1007/s00330-009-1470-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Revised: 04/24/2009] [Accepted: 04/30/2009] [Indexed: 12/16/2022]
Abstract
MRI, as a completely noninvasive technique, can provide quantitative assessment of perfusion, diffusion, viscoelasticity and metabolism, yielding diverse information about liver function. Furthermore, pathological accumulations of iron and lipids can be quantified. Perfusion MRI with various contrast agents is commonly used for the detection and characterization of focal liver disease and the quantification of blood flow parameters. An extended new application is the evaluation of the therapeutic effect of antiangiogenic drugs on liver tumours. Novel, but already widespread, is a histologically validated relaxometry method using five gradient echo sequences for quantifying liver iron content elevation, a measure of inflammation, liver disease and cancer. Because of the high perfusion fraction in the liver, the apparent diffusion coefficients strongly depend on the gradient factors used in diffusion-weighted MRI. While complicating analysis, this offers the opportunity to study perfusion without contrast injection. Another novel method, MR elastography, has already been established as the only technique able to stage fibrosis or diagnose mild disease. Liver fat content is accurately determined with multivoxel MR spectroscopy (MRS) or by faster MRI methods that are, despite their widespread use, prone to systematic error. Focal liver disease characterisation will be of great benefit once multivoxel methods with fat suppression are implemented in proton MRS, in particular on high-field MR systems providing gains in signal-to-noise ratio and spectral resolution.
Collapse
Affiliation(s)
- Paul E Sijens
- Radiology, University Medical Center Groningen and University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands.
| |
Collapse
|
30
|
Schwenzer NF, Springer F, Schraml C, Stefan N, Machann J, Schick F. Non-invasive assessment and quantification of liver steatosis by ultrasound, computed tomography and magnetic resonance. J Hepatol 2009; 51:433-45. [PMID: 19604596 DOI: 10.1016/j.jhep.2009.05.023] [Citation(s) in RCA: 528] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hepatic steatosis is the most prevalent liver disorder in the developed world. It is closely associated with features of metabolic syndrome, especially insulin resistance and obesity. The two most common conditions associated with fatty liver are alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD). Liver biopsy is considered the gold standard for the assessment of liver fat, but there is a need for less invasive diagnostic techniques. New imaging modalities are emerging, which could provide more detailed information about hepatic tissue or even replace biopsy. In the present review, available imaging modalities (ultrasound, computed tomography, magnetic resonance imaging and proton magnetic resonance spectroscopy) are presented which are employed to detect or even quantify the fat content of the liver. The advantages and disadvantages of the above-mentioned imaging modalities are discussed. Although none of these techniques is able to differentiate between microvesicular and macrovesicular steatosis and to reveal all features visible using histology, the proposed diagnostic modalities offer a wide range of additional information such as anatomical and morphological information non-invasively. In particular, magnetic resonance imaging and proton magnetic resonance spectroscopy are able to quantify the hepatic fat content hence avoiding exposure to radiation. Except for proton magnetic resonance spectroscopy, all modalities offer additional information about regional fat distribution within the liver. MR elastography, which can estimate the amount of fibrosis, also appears promising in the differentiation between simple steatosis and steatohepatitis.
Collapse
Affiliation(s)
- Nina F Schwenzer
- Section on Experimental Radiology, Department of Diagnostic and Interventional Radiology, Eberhard-Karls University, 72076 Tübingen, Germany
| | | | | | | | | | | |
Collapse
|
31
|
d'Assignies G, Ruel M, Khiat A, Lepanto L, Chagnon M, Kauffmann C, Tang A, Gaboury L, Boulanger Y. Noninvasive quantitation of human liver steatosis using magnetic resonance and bioassay methods. Eur Radiol 2009; 19:2033-40. [PMID: 19280194 DOI: 10.1007/s00330-009-1351-4] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2008] [Revised: 12/22/2008] [Accepted: 01/25/2009] [Indexed: 12/15/2022]
Abstract
The purpose was to evaluate the ability of three magnetic resonance (MR) techniques to detect liver steatosis and to determine which noninvasive technique (MR, bioassays) or combination of techniques is optimal for the quantification of hepatic fat using histopathology as a reference. Twenty patients with histopathologically proven steatosis and 24 control subjects underwent single-voxel proton MR spectroscopy (MRS; 3 voxels), dual-echo in phase/out of phase MR imaging (DEI) and diffusion-weighted MR imaging (DWI) examinations of the liver. Blood or urine bioassays were also performed for steatosis patients. Both MRS and DEI data allowed to detect steatosis with a high sensitivity (0.95 for MRS; 1 for DEI) and specificity (1 for MRS; 0.875 for DEI) but not DWI. Strong correlations were found between fat fraction (FF) measured by MRS, DEI and histopathology segmentation as well as with low density lipoprotein (LDL) and cholesterol concentrations. A Bland-Altman analysis showed a good agreement between the FF measured by MRS and DEI. Partial correlation analyses failed to improve the correlation with segmentation FF when MRS or DEI data were combined with bioassay results. Therefore, FF from MRS or DEI appear to be the best parameters to both detect steatosis and accurately quantify fat liver noninvasively.
Collapse
Affiliation(s)
- Gaspard d'Assignies
- Département de radiologie, Centre hospitalier de l'Université de Montréal, Montréal, Québec, Canada
| | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Guiu B, Loffroy R, Petit JM, Aho S, Ben Salem D, Masson D, Hillon P, Cercueil JP, Krause D. Mapping of liver fat with triple-echo gradient echo imaging: validation against 3.0-T proton MR spectroscopy. Eur Radiol 2009; 19:1786-93. [PMID: 19247667 DOI: 10.1007/s00330-009-1330-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2008] [Revised: 12/30/2008] [Accepted: 01/10/2009] [Indexed: 12/13/2022]
Abstract
The purpose of this study was to validate a magnetic resonance imaging (MRI) technique for mapping liver fat, using (1)H magnetic resonance spectroscopy ((1)H-MRS) as the reference standard. In 91 patients with type 2 diabetes, 3.0-T single-voxel point-resolved (1)H-MRS was used to calculate the liver fat fraction (LFF) from the water (4.76 ppm) and methylene (1.33 ppm) peaks, corrected for T1 and T2 decays. LFF (corrected for T1 and T2* decays) was also obtained from the mean signal intensity on a map built from a triple-echo (consecutive in-phase, opposed-phase, and in-phase echo times) breath-hold gradient echo sequence, using basic image calculation functions (arithmetic mean, subtraction, division, multiplication by a numerical factor). Mean LFF was 8.9% (range, 0.9-33.5) by MRI and 8.8% (range, 0-34.1) by (1)H-MRS. Pearson's coefficient was 0.976 (P < 0.0001) and Lin's coefficient was 0.975 (P < 0.0001). Liver segment had no significant influence. With Bland-Altman analysis, 95.6% (87/91) of data points were within the limits of agreement. Given its excellent agreement with (1)H-MRS, our mapping technique can be used for visual and quantitative evaluation of liver fat in everyday practice.
Collapse
Affiliation(s)
- Boris Guiu
- Department of Radiology, Le Bocage University Hospital, Bd Maréchal de Lattre de Tassigny, 21000, Dijon, France.
| | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Yokoo T, Bydder M, Hamilton G, Middleton MS, Gamst AC, Wolfson T, Hassanein T, Patton HM, Lavine JE, Schwimmer JB, Sirlin CB. Nonalcoholic fatty liver disease: diagnostic and fat-grading accuracy of low-flip-angle multiecho gradient-recalled-echo MR imaging at 1.5 T. Radiology 2009; 251:67-76. [PMID: 19221054 DOI: 10.1148/radiol.2511080666] [Citation(s) in RCA: 263] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
PURPOSE To assess the accuracy of four fat quantification methods at low-flip-angle multiecho gradient-recalled-echo (GRE) magnetic resonance (MR) imaging in nonalcoholic fatty liver disease (NAFLD) by using MR spectroscopy as the reference standard. MATERIALS AND METHODS In this institutional review board-approved, HIPAA-compliant prospective study, 110 subjects (29 with biopsy-confirmed NAFLD, 50 overweight and at risk for NAFLD, and 31 healthy volunteers) (mean age, 32.6 years +/- 15.6 [standard deviation]; range, 8-66 years) gave informed consent and underwent MR spectroscopy and GRE MR imaging of the liver. Spectroscopy involved a long repetition time (to suppress T1 effects) and multiple echo times (to estimate T2 effects); the reference fat fraction (FF) was calculated from T2-corrected fat and water spectral peak areas. Imaging involved a low flip angle (to suppress T1 effects) and multiple echo times (to estimate T2* effects); imaging FF was calculated by using four analysis methods of progressive complexity: dual echo, triple echo, multiecho, and multiinterference. All methods except dual echo corrected for T2* effects. The multiinterference method corrected for multiple spectral interference effects of fat. For each method, the accuracy for diagnosis of fatty liver, as defined with a spectroscopic threshold, was assessed by estimating sensitivity and specificity; fat-grading accuracy was assessed by comparing imaging and spectroscopic FF values by using linear regression. RESULTS Dual-echo, triple-echo, multiecho, and multiinterference methods had a sensitivity of 0.817, 0.967, 0.950, and 0.983 and a specificity of 1.000, 0.880, 1.000, and 0.880, respectively. On the basis of regression slope and intercept, the multiinterference (slope, 0.98; intercept, 0.91%) method had high fat-grading accuracy without statistically significant error (P > .05). Dual-echo (slope, 0.98; intercept, -2.90%), triple-echo (slope, 0.94; intercept, 1.42%), and multiecho (slope, 0.85; intercept, -0.15%) methods had statistically significant error (P < .05). CONCLUSION Relaxation- and interference-corrected fat quantification at low-flip-angle multiecho GRE MR imaging provides high diagnostic and fat-grading accuracy in NAFLD.
Collapse
Affiliation(s)
- Takeshi Yokoo
- Department of Radiology, University of California, San Diego Medical Center, University of California at San Diego, MR3 Laboratory, 408 Dickinson St, San Diego, CA 92103-8226, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Guiu B, Petit JM, Loffroy R, Ben Salem D, Aho S, Masson D, Hillon P, Krause D, Cercueil JP. Quantification of liver fat content: comparison of triple-echo chemical shift gradient-echo imaging and in vivo proton MR spectroscopy. Radiology 2009; 250:95-102. [PMID: 19092092 DOI: 10.1148/radiol.2493080217] [Citation(s) in RCA: 147] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE To validate a triple-echo gradient-echo sequence for measuring the fat content of the liver, by using hydrogen 1((1)H) magnetic resonance (MR) spectroscopy as the reference standard. MATERIALS AND METHODS This prospective study was approved by the appropriate ethics committee, and written informed consent was obtained from all patients. In 37 patients with type 2 diabetes (31 men, six women; mean age, 56 years), 3.0-T single-voxel point-resolved (1)H MR spectroscopy of the liver (Couinaud segment VII) was performed to calculate the liver fat fraction from the water (4.7 ppm) and methylene (1.3 ppm) peaks, corrected for T1 and T2 decay. Liver fat fraction was also computed from triple-echo (consecutive in-phase, opposed-phase, and in-phase echo times) breath-hold spoiled gradient-echo sequence (flip angle, 20 degrees), by estimating T2* and relative signal intensity loss between in- and opposed-phase values, corrected for T2* decay. Pearson correlation coefficient, Bland-Altman 95% limit of agreement, and Lin concordance coefficient were calculated. RESULTS Mean fat fractions calculated from the triple-echo sequence and (1)H MR spectroscopy were 10% (range, 0.7%-35.6%) and 9.7% (range, 0.2%-34.1%), respectively. Mean T2* time was 14.7 msec (range, 5.4-25.4 msec). Pearson correlation coefficient was 0.989 (P < .0001) and Lin concordance coefficient was 0.988 (P < .0001). With the Bland-Altman method, all data points were within the limits of agreement. CONCLUSION A breath-hold triple-echo gradient-echo sequence with a low flip angle and correction for T2* decay is accurate for quantifying fat in segment VII of the liver. Given its excellent correlation and concordance with (1)H MR spectroscopy, this triple-echo sequence could replace (1)H MR spectroscopy in longitudinal studies.
Collapse
Affiliation(s)
- Boris Guiu
- Department of Radiology, Le Bocage University Hospital, Bd Maréchal de Lattre de Tassigny, 21000 Dijon, France.
| | | | | | | | | | | | | | | | | |
Collapse
|