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Water Fat MRI

Thobias Romu, Nils Dahlström, Olof Dahlqvist Leinhard, Magnus Borga
PURPOSE: The purpose of this work was to develop and evaluate a robust water-fat separation method for T1-weighted symmetric two-point Dixon data. THEORY AND METHODS: A method for water-fat separation by phase unwrapping of the opposite-phase images by phase-sensitive reconstruction (PSR) is introduced. PSR consists of three steps; (1), identification of clusters of tissue voxels; (2), unwrapping of the phase in each cluster by solving Poisson's equation; and (3), finding the correct sign of each unwrapped opposite-phase cluster, so that the water-fat images are assigned the correct identities...
October 24, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Pasquina Marzola, Federico Boschi, Francesco Moneta, Andrea Sbarbati, Carlo Zancanaro
Localization, differentiation, and quantitative assessment of fat tissues have always collected the interest of researchers. Nowadays, these topics are even more relevant as obesity (the excess of fat tissue) is considered a real pathology requiring in some cases pharmacological and surgical approaches. Several weight loss medications, acting either on the metabolism or on the central nervous system, are currently under preclinical or clinical investigation. Animal models of obesity have been developed and are widely used in pharmaceutical research...
2016: Frontiers in Pharmacology
Rachel Golan, Ilan Shelef, Elad Shemesh, Yaakov Henkin, Dan Schwarzfuchs, Yftach Gepner, Ilana Harman-Boehm, Shula Witkow, Michael Friger, Yoash Chassidim, Idit F Liberty, Benjamin Sarusi, Dana Serfaty, Nitzan Bril, Michal Rein, Noa Cohen, Sivan Ben-Avraham, Uta Ceglarek, Michael Stumvoll, Matthias Blüher, Joachim Thiery, Meir J Stampfer, Assaf Rudich, Iris Shai
OBJECTIVE: To generate evidence-based conclusions about the effect of wine consumption on weight gain and abdominal fat accumulation and distribution in patients with type 2 diabetes. DESIGN: In the 2-year randomized controlled CASCADE (CArdiovaSCulAr Diabetes & Ethanol) trial, patients following a Mediterranean diet were randomly assigned to drink 150 ml of mineral water, white wine or red wine with dinner for 2 years. Visceral adiposity and abdominal fat distribution were measured in a subgroup of sixty-five participants, using abdominal MRI...
October 3, 2016: Public Health Nutrition
Valeria Ricotti, Matthew R B Evans, Christopher D J Sinclair, Jordan W Butler, Deborah A Ridout, Jean-Yves Hogrel, Ahmed Emira, Jasper M Morrow, Mary M Reilly, Michael G Hanna, Robert L Janiczek, Paul M Matthews, Tarek A Yousry, Francesco Muntoni, John S Thornton
OBJECTIVE: A number of promising experimental therapies for Duchenne muscular dystrophy (DMD) are emerging. Clinical trials currently rely on invasive biopsies or motivation-dependent functional tests to assess outcome. Quantitative muscle magnetic resonance imaging (MRI) could offer a valuable alternative and permit inclusion of non-ambulant DMD subjects. The aims of our study were to explore the responsiveness of upper-limb MRI muscle-fat measurement as a non-invasive objective endpoint for clinical trials in non-ambulant DMD, and to investigate the relationship of these MRI measures to those of muscle force and function...
2016: PloS One
Guanwu Li, Zheng Xu, Jingzheng Fan, Wei Yuan, Lina Zhang, Lingmi Hou, Dongmei Wu, Shixin Chang, Horea Calimente, Jiani Hu
OBJECTIVE: To assess the differential features of marrow adiposity between osteoarthritis (OA) and osteoporosis (OP) in postmenopausal women using water/fat MRI. METHODS: This cross-sectional study included 97 postmenopausal women (OA [n = 25], OA + osteopenia [n = 27], OA + OP [n = 23], and OP groups [n = 22]). Water/fat MRI, dual-energy x-ray absorptiometry and biochemical analysis were performed to assess vertebral marrow fat fraction, bone mineral density, and bone biomarkers, respectively...
September 19, 2016: Menopause: the Journal of the North American Menopause Society
Lena K L Oestreich, Ofer Pasternak, Martha E Shenton, Marek Kubicki, Xue Gong, Simon McCarthy-Jones, Thomas J Whitford
BACKGROUND: There is growing evidence to suggest that delusions associated with schizophrenia arise from altered structural brain connectivity. The present study investigated whether structural changes in three major fasciculi that interconnect the limbic system - the cingulum bundle, uncinate fasciculus and fornix - are associated with delusions in chronic schizophrenia patients. METHODS: Free-water corrected Diffusion Tensor Imaging was used to investigate the association between delusions and both microstructural changes within these three fasciculi and extracellular changes in the surrounding free-water...
2016: NeuroImage: Clinical
Dian Liu, Helen L Parker, Jelena Curcic, Sebastian Kozerke, Andreas Steingoetter
BACKGROUND: Oil-in-water emulsions have recently become of interest to nutritional sciences because of their ability to influence gastrointestinal digestive processes and ultimately benefit human health. MRI offers the potential to noninvasively characterize the interaction between emulsified lipids and gastric secretion within the stomach. OBJECTIVES: We determined noninvasively how emulsion stability modulates volumes of fat and secretion, layering of fat, and the mixing of emulsified fat with secretion within the stomach...
October 2016: Journal of Nutrition
Anette Karlsson, Olof Dahlqvist Leinhard, Ulrika Åslund, Janne West, Thobias Romu, Örjan Smedby, Peter Zsigmond, Anneli Peolsson
Study Design Cross-sectional study. Background Findings of fat infiltration in cervical spine multifidus, as a sign of degenerative morphometric changes due to whiplash injury, need to be verified. Objectives To develop a method using water/fat magnetic resonance imaging (MRI) to investigate fat infiltration and cross-sectional area of multifidus muscle in individuals with whiplash-associated disorders (WADs) compared to healthy controls. Methods Fat infiltration and cross-sectional area in the multifidus muscles spanning the C4 to C7 segmental levels were investigated by manual segmentation using water/fat-separated MRI in 31 participants with WAD and 31 controls, matched for age and sex...
October 2016: Journal of Orthopaedic and Sports Physical Therapy
Weiguo Li, Xifu Wang, Frank H Miller, Andrew C Larson
PURPOSE: The purpose of this work was to develop a chemical shift magnetization transfer (CSMT) magnetic resonance imaging (MRI) method to provide accurate magnetization transfer ratio (MTR) measurements in the presence of fat. METHODS: Numerical simulations were performed to compare MTR measurements at different echo times (TEs) for voxels with varying fat/water content. The CSMT approach was developed using water fraction estimates to correct for the impact of fat signal upon observed MTR measurements...
August 31, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Giulio Siracusano, Aurelio La Corte, Carmelo Milazzo, Giuseppe Pio Anastasi, Giovanni Finocchio, Michele Gaeta
PURPOSE: Investigation of the feasibility of the R2(⁎) mapping techniques by using latest theoretical models corrected for confounding factors and optimized for signal to noise ratio. THEORY AND METHODS: The improvement of the performance of state of the art magnetic resonance imaging (MRI) relaxometry algorithms is challenging because of a non-negligible bias and still unresolved numerical instabilities. Here, R2(⁎) mapping reconstructions, including complex fitting with multi-spectral fat-correction by using single-decay and double-decay formulation, are deeply studied in order to investigate and identify optimal configuration parameters and minimize the occurrence of numerical artifacts...
August 26, 2016: Magnetic Resonance Imaging
Fabian Gilbert, Dirk Böhm, Lars Eden, Jonas Schmalzl, Rainer H Meffert, Herbert Köstler, Andreas M Weng, Dirk Ziegler
BACKGROUND: The Goutallier Classification is a semi quantitative classification system to determine the amount of fatty degeneration in rotator cuff muscles. Although initially proposed for axial computer tomography scans it is currently applied to magnet-resonance-imaging-scans. The role for its clinical use is controversial, as the reliability of the classification has been shown to be inconsistent. The purpose of this study was to compare the semi quantitative MRI-based Goutallier Classification applied by 5 different raters to experimental MR spectroscopic quantitative fat measurement in order to determine the correlation between this classification system and the true extent of fatty degeneration shown by spectroscopy...
2016: BMC Musculoskeletal Disorders
Sergios Gatidis, Hansjörg Graf, Jakob Weiß, Alto Stemmer, Berthold Kiefer, Konstantin Nikolaou, Mike Notohamiprodjo, Petros Martirosian
OBJECTIVE: Our objective was to compare available techniques reducing artifacts in echo planar imaging (EPI)-based diffusion-weighed magnetic resonance imaging MRI (DWI) of the neck at 3 Tesla caused by B0-field inhomogeneities. MATERIALS AND METHODS: A cylindrical fat-water phantom was equipped with a Maxwell coil allowing for additional linear B0-field variations in z-direction. The effect of increasing strength of this superimposed gradient on image quality was observed using a standard single-shot EPI-based DWI sequence (sEPI), a zoomed single-shot EPI sequence (zEPI), a readout-segmented EPI sequence (rsEPI), and an sEPI sequence with integrated dynamic shimming (intEPI) on a 3-Tesla system...
August 8, 2016: Magma
Jun Shen, Thomas Baum, Christian Cordes, Beate Ott, Thomas Skurk, Hendrik Kooijman, Ernst J Rummeny, Hans Hauner, Bjoern H Menze, Dimitrios C Karampinos
PURPOSE: To develop a fully automatic algorithm for abdominal organs and adipose tissue compartments segmentation and to assess organ and adipose tissue volume changes in longitudinal water-fat magnetic resonance imaging (MRI) data. MATERIALS AND METHODS: Axial two-point Dixon images were acquired in 20 obese women (age range 24-65, BMI 34.9±3.8kg/m(2)) before and after a four-week calorie restriction. Abdominal organs, subcutaneous adipose tissue (SAT) compartments (abdominal, anterior, posterior), SAT regions along the feet-head direction and regional visceral adipose tissue (VAT) were assessed by a fully automatic algorithm using morphological operations and a multi-atlas-based segmentation method...
September 2016: European Journal of Radiology
Bruce M Damon, Ke Li, Nathan D Bryant
Neuromuscular diseases often exhibit a temporally varying, spatially heterogeneous, and multifaceted pathology. The goals of this chapter are to describe and evaluate the use of quantitative magnetic resonance imaging (MRI) methods to characterize muscle pathology. The following criteria are used for this evaluation: objective measurement of continuously distributed variables; clear and well-understood relationship to the pathology of interest; sensitivity to improvement or worsening of clinical status; and the measurement properties of accuracy and precision...
2016: Handbook of Clinical Neurology
Dirk Fischer, Ulrike Bonati, Mike P Wattjes
PURPOSE OF REVIEW: In this update, we describe recent findings on imaging techniques used for the analysis and quantification of affected muscles, advances in pattern recognition, and quantitative muscle imaging in clinical studies. RECENT FINDINGS: Whole-body muscle MRI and meta-analytical approaches, so-called (hierarchical) heat maps of affected muscles are promising advances compared with commonly applied lower leg pattern recognition approaches. Muscle fat fraction assessments measuring chemical shift differences and T2-relaxation times of separated fat and water components in skeletal muscle are currently the most reliable quantitative muscle imaging techniques...
October 2016: Current Opinion in Neurology
Vanessa Stahl, Florian Maier, Martin T Freitag, Ralf O Floca, Moritz C Berger, Reiner Umathum, Mauricio Berriel Diaz, Stephan Herzig, Marc-André Weber, Antonia Dimitrakopoulou-Strauss, Kristian Rink, Peter Bachert, Mark E Ladd, Armin M Nagel
PURPOSE: To evaluate the volume and changes of human brown adipose tissue (BAT) in vivo following exposure to cold using magnetic resonance imaging (MRI). MATERIALS AND METHODS: The clavicular region of 10 healthy volunteers was examined with a 3T MRI system. One volunteer participated twice. A cooling vest that was circulated with temperature-controlled water was used to expose each volunteer to a cold environment. Three different water temperature phases were employed: baseline (23°C, 20 min), cooling (12°C, 90 min), and a final warming phase (37°C, 30 min)...
July 15, 2016: Journal of Magnetic Resonance Imaging: JMRI
Valentina Mazzoli, Aart J Nederveen, Jos Oudeman, Andre Sprengers, Klaas Nicolay, Gustav J Strijkers, Nico Verdonschot
PURPOSE: To introduce a method for obtaining fat-suppressed images in real-time MRI of moving joints at 3 Tesla (T) using a bSSFP sequence with phase detection to enhance visualization of soft tissue structures during motion. METHODS: The wrist and knee of nine volunteers were imaged with a real-time bSSFP sequence while performing dynamic tasks. For appropriate choice of sequence timing parameters, water and fat pixels showed an out-of-phase behavior, which was exploited to reconstruct water and fat images...
July 15, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
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
Tilman Schubert, Peter Bannas, Sonja Kinner, Samir Sharma, James H Holmes, Mahdi Salmani Rahimi, Frank R Korosec, Scott B Reeder
PURPOSE: To evaluate the incidence and severity of potentially thrombus mimicking, flow-induced misallocation artifacts in a clinical setting. Two-point "Dixon" fat-water separation methods, with bipolar readout gradients, may suffer from flow-induced fat-water misallocation artifacts. If these artifacts occur within blood vessels, they may mimic thrombus. MATERIALS AND METHODS: Two-point Dixon coronal and axial images acquired in 102 consecutive patients were retrospectively evaluated for the presence of flow-induced artifacts in arteries and veins...
July 5, 2016: Journal of Magnetic Resonance Imaging: JMRI
Takatoshi Aoki, Shinpei Yamaguchi, Shunsuke Kinoshita, Yoshiko Hayashida, Yukunori Korogi
OBJECTIVE: To determine the reproducibility of the quantitative chemical shift-based water-fat separation method with a multiecho gradient echo sequence [iteraterative decomposition of water and fat with echo asymmetry and least-squares estimation quantitation sequence (IDEAL-IQ)] for assessing bone marrow fat fraction (FF); to evaluate variation of FF at different bone sites; and to investigate its association with age and menopause. METHODS: 31 consecutive females who underwent pelvic iterative decomposition of water and fat with echo asymmetry and least-squares estimation at 3-T MRI were included in this study...
September 2016: British Journal of Radiology
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