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Proton density fat fraction

Harald Kramer, Perry J Pickhardt, Mark A Kliewer, Diego Hernando, Guang-Hong Chen, James A Zagzebski, Scott B Reeder
OBJECTIVE: The purpose of this study was to prospectively evaluate the accuracy of proton-density fat-fraction, single- and dual-energy CT (SECT and DECT), gray-scale ultrasound (US), and US shear-wave elastography (US-SWE) in the quantification of hepatic steatosis with MR spectroscopy (MRS) as the reference standard. SUBJECTS AND METHODS: Fifty adults who did not have symptoms (23 men, 27 women; mean age, 57 ± 5 years; body mass index, 27 ± 5) underwent liver imaging with un-enhanced SECT, DECT, gray-scale US, US-SWE, proton-density fat-fraction MRI, and MRS for this prospective trial...
October 11, 2016: AJR. American Journal of Roentgenology
Paul M Manning, Gavin Hamilton, Kang Wang, Chulhyun Park, Jonathan C Hooker, Tanya Wolfson, Anthony Gamst, William M Haufe, Alex N Schlein, Michael S Middleton, Claude B Sirlin
PURPOSE: To compare agreement between region-of-interest (ROI)- and parametric map-based methods of hepatic proton density fat fraction (PDFF) estimation in adults with known or suspected hepatic steatosis secondary to chronic liver disease over a range of imaging and analysis conditions. MATERIALS AND METHODS: In this IRB approved HIPAA compliant prospective single-site study, 31 adults with chronic liver disease undergoing clinical gadoxetic acid-enhanced liver magnetic resonance imaging at 3 T were recruited...
September 29, 2016: Abdominal Radiology
Timothy J Colgan, Diego Hernando, Samir D Sharma, Scott B Reeder
PURPOSE: The purpose of this work was to characterize the effects of concomitant gradients (CGs) on chemical shift encoded (CSE)-based estimation of B0 field map, proton density fat fraction (PDFF), and R2*. THEORY: A theoretical framework was used to determine the effects of CG-induced phase errors on CSE-MRI data. METHODS: Simulations, phantom experiments, and in vivo experiments were conducted at 3 Tesla to assess the effects of CGs on quantitative CSE-MRI techniques...
September 21, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Janki Patel, Ricki Bettencourt, Jeffrey Cui, Joanie Salotti, Jonathan Hooker, Archana Bhatt, Carolyn Hernandez, Phirum Nguyen, Hamed Aryafar, Mark Valasek, William Haufe, Catherine Hooker, Lisa Richards, Claude B Sirlin, Rohit Loomba
BACKGROUND: Magnetic resonance imaging-estimated proton-density-fat-fraction (MRI-PDFF) has been shown to be a noninvasive, accurate and reproducible imaging-based biomarker for assessing steatosis and treatment response in nonalcoholic steatohepatitis (NASH) clinical trials. However, there are no data on the magnitude of MRI-PDFF reduction corresponding to histologic response in the setting of a NASH clinical trial. The aim of this study was to quantitatively compare the magnitude of MRI-PDFF reduction between histologic responders versus histologic nonresponders in NASH patients...
September 2016: Therapeutic Advances in Gastroenterology
Jingqi Zhu, Lin Zhang, Xing Wu, Zuogang Xiong, Yuyou Qiu, Ting Hua, Guangyu Tang
Purpose To determine the longitudinal relationships among lumbar vertebral blood perfusion, bone mass, and marrow adipose tissue in a rat osteoporosis model after ovariectomy by using quantitative dynamic contrast agent-enhanced (DCE) magnetic resonance (MR) imaging, microcomputed tomography (micro-CT), and proton MR spectroscopy. Materials and Methods In this animal review committee-approved study, lumbar vertebrae were evaluated through MR spectroscopy, quantitative DCE MR imaging, micro-CT, and histopathologic analysis, and blood was examined at 0, 2, 6, 10, 14, 18, and 24 weeks after ovariectomy consisting of exposure of the ovaries but no excision (n = 35) or sham operation, defined as exposure of the ovaries but no excision (n = 35)...
August 19, 2016: Radiology
Debra E Horng, Diego Hernando, Scott B Reeder
PURPOSE: To evaluate the accuracy of R2* models (1/T2 * = R2*) for chemical shift-encoded magnetic resonance imaging (CSE-MRI)-based proton density fat-fraction (PDFF) quantification in patients with fatty liver and iron overload, using MR spectroscopy (MRS) as the reference standard. MATERIALS AND METHODS: Two Monte Carlo simulations were implemented to compare the root-mean-squared-error (RMSE) performance of single-R2* and dual-R2* correction in a theoretical liver environment with high iron...
July 13, 2016: Journal of Magnetic Resonance Imaging: JMRI
Guanwu Li, Zheng Xu, Hao Gu, Xuefeng Li, Wei Yuan, Shixin Chang, Jingzheng Fan, Horea Calimente, Jiani Hu
PURPOSE: To validate a chemical shift-encoded (CSE) water-fat imaging for quantifying marrow fat fraction (FF), using proton magnetic resonance spectroscopy (MRS) as reference. MATERIALS AND METHODS: Multiecho T2 -corrected MRS and CSE imaging with eight-echo gradient-echo acquisitions at 3T were performed to calculate marrow FF in 83 subjects, including 41 with normal bone mineral density (BMD), 26 with osteopenia, and 16 with osteoporosis (based on DXA). Eight participants were scanned three times with repositioning to assess the repeatability of CSE FF map measurements...
June 24, 2016: Journal of Magnetic Resonance Imaging: JMRI
Jeffrey Cui, Chi-Hua Chen, Min-Tzu Lo, Nicholas Schork, Ricki Bettencourt, Monica P Gonzalez, Archana Bhatt, Jonathan Hooker, Katherine Shaffer, Karen E Nelson, Michelle T Long, David A Brenner, Claude B Sirlin, Rohit Loomba, For The Genetics Of Nafld In Twins Consortium
: Nonalcoholic fatty liver disease is associated with metabolic risk factors including hypertension and dyslipidemia and may progress to liver fibrosis. Studies have shown that hepatic steatosis and fibrosis are heritable, but whether they have a significant shared gene effect is unknown. This study examined the shared gene effects between hepatic steatosis and fibrosis and their associations with metabolic risk factors. This was a cross-sectional analysis of a prospective cohort of well-characterized, community-dwelling twins (45 monozygotic, 20 dizygotic twin pairs, 130 total subjects) from southern California...
November 2016: Hepatology: Official Journal of the American Association for the Study of Liver Diseases
Tomohiro Ueno, Hirokazu Suzuki, Masahiro Hiraishi, Hideaki Amano, Hidenao Fukuyama, Naozo Sugimoto
In medical and pharmacological research, various human disease models in small fish, such as medaka (Oryzias latipes), have been created. To investigate these disease models noninvasively, magnetic resonance imaging (MRI) is suitable because these small fish are no longer transparent as adults. However, their small body size requires a high spatial resolution, and a water pool should be avoided to maximize the strength of MRI. We developed in vivo magnetic resonance microscopy (MR microscopy) without a water pool by combining hypothermic anaesthesia and a 14...
2016: Scientific Reports
Henry H Ong, Corey D Webb, Marnie L Gruen, Alyssa H Hasty, John C Gore, E Brian Welch
Quantitative fat-water MRI (FWMRI) methods provide valuable information about the distribution, volume, and composition of adipose tissue (AT). Ultra high field FWMRI of animal models may have the potential to provide insights into the progression of obesity and its comorbidities. Here, we present quantitative FWMRI with all known confounder corrections on a 15.2T preclinical scanner for noninvasive in vivo monitoring of an established diet-induced obesity mouse model. Male C57BL/6J mice were placed on a low-fat (LFD) or a high-fat diet (HFD)...
April 2016: Journal of Medical Imaging
Christoph Mahlke, Diego Hernando, Christina Jahn, Antonio Cigliano, Till Ittermann, Anne Mössler, Marie-Luise Kromrey, Grazyna Domaska, Scott B Reeder, Jens-Peter Kühn
PURPOSE: To investigate the feasibility of estimating the proton-density fat fraction (PDFF) using a 7.1T magnetic resonance imaging (MRI) system and to compare the accuracy of liver fat quantification using different fitting approaches. MATERIALS AND METHODS: Fourteen leptin-deficient ob/ob mice and eight intact controls were examined in a 7.1T animal scanner using a 3D six-echo chemical shift-encoded pulse sequence. Confounder-corrected PDFF was calculated using magnitude (magnitude data alone) and combined fitting (complex and magnitude data)...
May 19, 2016: Journal of Magnetic Resonance Imaging: JMRI
Jeffrey Cui, Len Philo, Phirum Nguyen, Heather Hofflich, Carolyn Hernandez, Ricki Bettencourt, Lisa Richards, Joanie Salotti, Archana Bhatt, Jonathan Hooker, William Haufe, Catherine Hooker, David A Brenner, Claude B Sirlin, Rohit Loomba
BACKGROUND & AIMS: Uncontrolled studies show sitagliptin, an oral DPP-4 inhibitor, may improve alanine aminotransferase and liver histology in non-alcoholic fatty liver disease (NAFLD) patients. We aimed to compare sitagliptin vs. the efficacy of a placebo in reducing liver fat measured by MRI-derived proton density-fat fraction (MRI-PDFF). METHODS: This randomized, double-blind, allocation-concealed, placebo-controlled trial included 50 NAFLD patients with prediabetes or early diabetes randomized to sitagliptin orally 100mg/day or placebo for 24weeks...
August 2016: Journal of Hepatology
Ziyue Wu, Weiyi Chen, Krishna S Nayak
OBJECTIVE: To develop and evaluate a framework for simulating low-field proton-density weighted MRI acquisitions based on high-field acquisitions, which could be used to predict the minimum B0 field strength requirements for MRI techniques. This framework would be particularly useful in the evaluation of de-noising and constrained reconstruction techniques. MATERIALS AND METHODS: Given MRI raw data, lower field MRI acquisitions can be simulated based on the signal and noise scaling with field strength...
2016: PloS One
Elina M Petäjä, Hannele Yki-Järvinen
Non-alcoholic fatty liver disease (NAFLD) covers a spectrum of disease ranging from simple steatosis (NAFL) to non-alcoholic steatohepatitis (NASH) and fibrosis. "Obese/Metabolic NAFLD" is closely associated with obesity and insulin resistance and therefore predisposes to type 2 diabetes and cardiovascular disease. NAFLD can also be caused by common genetic variants, the patatin-like phospholipase domain-containing 3 (PNPLA3) or the transmembrane 6 superfamily member 2 (TM6SF2). Since NAFL, irrespective of its cause, can progress to NASH and liver fibrosis, its definition is of interest...
2016: International Journal of Molecular Sciences
Diego Hernando, Samir D Sharma, Mounes Aliyari Ghasabeh, Bret D Alvis, Sandeep S Arora, Gavin Hamilton, Li Pan, Jean M Shaffer, Keitaro Sofue, Nikolaus M Szeverenyi, E Brian Welch, Qing Yuan, Mustafa R Bashir, Ihab R Kamel, Mark J Rice, Claude B Sirlin, Takeshi Yokoo, Scott B Reeder
PURPOSE: To evaluate the accuracy and reproducibility of quantitative chemical shift-encoded (CSE) MRI to quantify proton-density fat-fraction (PDFF) in a fat-water phantom across sites, vendors, field strengths, and protocols. METHODS: Six sites (Philips, Siemens, and GE Healthcare) participated in this study. A phantom containing multiple vials with various oil/water suspensions (PDFF:0%-100%) was built, shipped to each site, and scanned at 1.5T and 3T using two CSE protocols per field strength...
April 15, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Keitaro Sofue, Xiaodong Zhong, Marcel D Nickel, Brian M Dale, Mustafa R Bashir
OBJECTIVE: To assess changes in liver proton density fat fraction (PDFF) and R 2* measurements in the presence of changes in tissue relaxation rates induced by administrating gadoxetic acid, using two different image reconstruction methods at 3T MRI. METHODS: Forty-five patients were imaged at 3T with chemical-shift-based MRI sequences before and 20 min after administration of gadoxetic acid. Image reconstructions were performed using hybrid and complex methods to obtain PDFF and R 2* images...
August 2016: Abdominal Radiology
Takeshi Yokoo, Haley R Clark, Ivan Pedrosa, Qing Yuan, Ivan Dimitrov, Yue Zhang, Ildiko Lingvay, Muhammad S Beg, I Alexandru Bobulescu
PURPOSE: To evaluate renal lipid content in subjects with and without type II diabetes mellitus (DM2) using Dixon-based magnetic resonance imaging (MRI). MATERIALS AND METHODS: This retrospective study was approved by the Institutional Review Board and compliant with the Health Insurance Portability and Accountability Act. Sixty-nine adults with or without DM2 (n = 29, n = 40) underwent 3T MRI of the abdomen using 3D multiecho Dixon gradient-echo acquisition and proton-density fat fraction (FF) reconstruction...
March 23, 2016: Journal of Magnetic Resonance Imaging: JMRI
Thomas Baum, Stephanie Inhuber, Michael Dieckmeyer, Christian Cordes, Stefan Ruschke, Elisabeth Klupp, Pia M Jungmann, Rosanna Farlock, Holger Eggers, Hendrik Kooijman, Ernst J Rummeny, Ansgar Schwirtz, Jan S Kirschke, Dimitrios C Karampinos
Magnetic resonance-based assessment of quadriceps muscle fat has been proposed as surrogate marker in sarcopenia, osteoarthritis, and neuromuscular disorders. We presently investigated the association of quadriceps muscle fat with isometric strength measurements in healthy males using chemical shift encoding-based water-fat magnetic resonance imaging. Intermuscular adipose tissue fraction and intramuscular proton density fat fraction correlated significantly (P < 0.05) with isometric strength (up to r = -0...
May 2016: Journal of Computer Assisted Tomography
Bing Wu, Wei Han, Zhenhong Li, Yonghua Zhao, Mingmei Ge, Xueqing Guo, Xinhuai Wu
The purpose of this study was to prospectively evaluate the reproducibility of the proton density fat-fraction (PDFF) of the liver using the IDEAL algorithm, a quantitative confounder-corrected chemical-shift-encoded MRI method. Data were obtained from 15 volunteers on four different days. The first and the third examinations were conducted on scanner one with one-week intervals, while the second and the fourth tests were performed on scanner two with same time interval. For each test, two MR scans were performed, one before and one after a meal...
2016: Scientific Reports
İlkay S İdilman, Deniz Akata, Mustafa Nasuh Özmen, Muşturay Karçaaltıncaba
Magnetic resonance imaging (MRI) is a well-established imaging modality to evaluate increased iron deposition in the liver. Both standard liver imaging series with in-phase and out-of-phase T1-weighted sequences for visual detection, as well as advanced T2- and T2*-weighted measurements may be used for mapping the iron concentration. In this article, we describe different forms of liver iron accumulation (diffuse, heterogeneous, multinodular, focal, segmental, intralesional, periportal, and lobar) and hepatic iron sparing (focal, geographic and nodular)...
January 2016: Diagnostic and Interventional Radiology: Official Journal of the Turkish Society of Radiology
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