Read by QxMD icon Read

Water Fat MRI

Naoki Ohno, Tosiaki Miyati, Shuto Suzuki, Hirohito Kan, Toshitaka Aoki, Yoshitaka Nakamura, Yuki Hiramatsu, Satoshi Kobayashi, Toshifumi Gabata
PURPOSE: To suppress olefinic signals and enable simultaneous and quantitative estimation of multiple functional parameters associated with water and lipid, we investigated a modified method using chemical shift displacement and recovery-based separation of lipid tissue (SPLIT) involving acquisitions with different inversion times (TIs), echo times (TEs), and b-values. MATERIALS AND METHODS: Single-shot diffusion echo-planar imaging (SSD-EPI) with multiple b-values (0-3000 s/mm2 ) was performed without fat suppression to separate water and lipid images using the chemical shift displacement of lipid signals in the phase-encoding direction...
March 12, 2018: Magnetic Resonance Imaging
Sridhar Vajapeyam, Kirsten Ecklund, Robert V Mulkern, Henry A Feldman, Jennifer M O'Donnell, Amy D DiVasta, Clifford J Rosen, Catherine M Gordon
PURPOSE: Dehydroepiandrosterone (DHEA)+estrogen/progestin therapy for adolescent girls with anorexia nervosa (AN) has the potential to arrest bone loss. The primary aim of this study was to test the effects of DHEA+estrogen/progestin therapy in adolescent girls with AN on bone marrow in the distal femur using magnetic resonance imaging (MRI) and spectroscopy. METHODS: Seventy adolescent girls with AN were enrolled in a double blind, randomized, placebo-controlled trial at two urban hospital-based programs...
February 26, 2018: Bone
Eric G Stinson, Joshua D Trzasko, Norbert G Campeau, James F Glockner, John Huston, Phillip M Young, Stephen J Riederer
PURPOSE: Dixon-based fat suppression has recently gained interest for dynamic contrast-enhanced MRI, but multi-echo techniques require longer scan times and reduce temporal resolution compared to single-echo alternatives without fat suppression. The purpose of this work is to demonstrate accelerated single-echo Dixon imaging with high spatial and temporal resolution. THEORY AND METHODS: Real-valued water and fat images can be obtained from a single measurement if the shared initial phase and that due to ΔB0 are assumed known a priori...
February 27, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Colin McQuade, Peadar S Waters, Ciara O'Brien, Stephen Crowther, William Torreggiani, Dara O Kavanagh
INTRODUCTION: Intussusception in adults is a rare condition, accounting for just 5% of all cases. Approximately 50% of cases of large intestine intussusception occur due to a malignant neoplasm. We present here a novel case report of colo-rectal intussusception arising secondary to a primary rectal melanoma. PRESENTATION OF CASE: We present the case of an 85 year-old patient, who underwent a colonoscopy for investigation of weight loss and altered bowel habit. At colonoscopy, a pigmented polypoid mass was visualised in the upper third of the rectum...
February 14, 2018: International Journal of Surgery Case Reports
Daiki Tamada, Tetsuya Wakayama, Hiroshi Onishi, Utaroh Motosugi
PURPOSE: To develop multiparameter mapping including T1 , R2*, and proton density fat fraction with a single breath-hold to evaluate liver disease and liver function. METHODS: A 6-echo spoiled gradient-echo sequence with dual flip angles was used to acquire a 12-set MRI volume data set. To shorten the scan time, undersampling and multicontrast compressed-sensing reconstruction were used. The scan time was 18 seconds. R2* and proton density fat fraction mapping were achieved by using the iterative least-squares method...
February 24, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Huimin Lin, Hongjiang Wei, Naying He, Caixia Fu, Shu Cheng, Jun Shen, Baisong Wang, Xu Yan, Chunlei Liu, Fuhua Yan
PURPOSES: To evaluate the feasibility of simultaneous quantification of liver iron concentration (LIC) and fat fraction (FF) using water-fat separation and quantitative susceptibility mapping (QSM). METHODS: Forty-five patients suspected of liver iron overload (LIO) were included. A volumetric interpolated breath-hold examination sequence for QSM and FF, a fat-saturated gradient echo sequence for R2 * , a spin echo sequence for LIC measurements and MRS analyses for FF (FF-MRS) were performed...
February 22, 2018: European Radiology
Jinsoo Uh, Matthew J Krasin, Chia-Ho Hua
PURPOSE: To evaluate the feasibility of using on-treatment magnetic resonance imaging (MRI) to detect proton range changes during treatment courses. METHODS: MRI-based virtual computed tomography (vCT) was generated to calculate water-equivalent path length (WEPL) at the distal surface of a clinical target volume. T2-weighted MR images with and without fat suppression were processed by thresholding and fuzzy c-mean clustering to assign a bulk HU (Hounsfield Unit) to each segment of fat, water, and air...
February 21, 2018: Medical Physics
Christoph Kopp, Peter Linz, Carolin Maier, Peter Wabel, Matthias Hammon, Armin M Nagel, Daniela Rosenhauer, Stephan Horn, Michael Uder, Friedrich C Luft, Jens Titze, Anke Dahlmann
Long-term elevated blood sugar levels result in tissue matrix compositional changes in patients with diabetes mellitus type 2 (T2DM). We hypothesized that hemodialysis patients with T2DM might accumulate more tissue sodium than control hemodialysis patients. To test this,23 Na magnetic resonance imaging (23 Na MRI) was used to estimate sodium in skin and muscle tissue in hemodialysis patients with or without T2DM. Muscle fat content was estimated by1 H MRI and tissue sodium content by23 Na MRI pre- and post-hemodialysis in ten hemodialysis patients with T2DM and in 30 matched control hemodialysis patients...
February 15, 2018: Kidney International
Junmin Liu, Spencer D Christiansen, Maria Drangova
Multi-echo gradient echo (mGRE) sequences have been widely adapted in clinical and scientific practice for different purposes to their capability of performing Dixon MRI, generating multi-contrast images and extracting multi-parametric maps. This work aims to extend mGRE-based techniques for imaging whole head, where further technical developments are required due to the co-existence of fat and large B0 inhomogeneity in regions such as the skull base and neck. Specifically, bipolar mGRE data were acquired with a single sequence that contains both a short echo-spacing (ΔTE) echo train to capture water-fat and B0 phase shifts (for proton density fat-fraction (FF) and B0 mapping) and a longer ΔTE echo train (and long echo times) to capture subtle susceptibility variations and R2* information...
February 13, 2018: NeuroImage
Kevin J Sinclair, Lanette J Friesen-Waldner, Colin M McCurdy, Curtis N Wiens, Trevor P Wade, Barbra de Vrijer, Timothy R H Regnault, Charles A McKenzie
PURPOSE: To examine the feasibility of using MRI to identify differences in liver size and fat deposition in fetal guinea pigs exposed to an in utero environment influenced by maternal consumption of a Western diet. MATERIALS AND METHODS: Female guinea pigs fed either an energy-dense Western Diet (WD), comprised of increased saturated fats and simple sugars, or a Control Diet (CD) from weaning through pregnancy, underwent MR scanning near term (~ 60 days; term ~ 69 days)...
2018: PloS One
Xinzeng Wang, Ali Pirasteh, James Brugarolas, Neil M Rofsky, Robert E Lenkinski, Ivan Pedrosa, Ananth J Madhuranthakam
PURPOSE: To develop a whole-body MRI technique at 3T with improved lesion conspicuity for metastatic cancer detection using fast, high-resolution and high SNR T 2 -weighted (T 2 W) imaging with simultaneous fat and fluid suppression. THEORY AND METHODS: The proposed dual-echo T 2 -weighted acquisition for enhanced conspicuity of tumors (DETECT) acquires 4 images, in-phase (IP) and out-of-phase (OP) at a short and a long TE using single-shot turbo spin echo. The IP/OP images at the short and long TEs are reconstructed using the standard Dixon and shared-field-map Dixon reconstruction respectively, for robust fat-water separation...
February 14, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Jorge E Jimenez, Roberta M Strigel, Kevin M Johnson, Leah C Henze Bancroft, Scott B Reeder, Walter F Block
PURPOSE: To develop a volumetric imaging technique with 0.8-mm isotropic resolution and 10-s/volume rate to detect and analyze breast lesions in a bilateral, dynamic, contrast-enhanced MRI exam. METHODS: A local low-rank temporal reconstruction approach that also uses parallel imaging and spatial compressed sensing was designed to create rapid volumetric frame rates during a contrast-enhanced breast exam (vastly undersampled isotropic projection [VIPR] spatial compressed sensing with temporal local low-rank [STELLR])...
February 14, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Tatsuya Hayashi, Kei Fukuzawa, Hidekazu Yamazaki, Takashi Konno, Tosiaki Miyati, Jun'ichi Kotoku, Hiroshi Oba, Hiroshi Kondo, Keiko Toyoda, Satoshi Saitoh
PURPOSE: To evaluate the reproducibility of proton density fat fraction (PDFF) and T2* in a fat-water phantom on three different 3 T MRI systems using 6-point DIXON methods. METHODS: A phantom which included varying fat volume percentages (true fat fraction [FF]) was scanned by three 3 T MR machines, and PDFF and T2* were measured. RESULTS: The mean difference between true FF and PDFF was small in all vendors (-2.11% to 0.41%). However, the difference ratio for T2* values was large among vendors (1...
February 2, 2018: Clinical Imaging
Janne West, Thobias Romu, Sofia Thorell, Hanna Lindblom, Emilia Berin, Anna-Clara Spetz Holm, Lotta Lindh Åstrand, Anette Karlsson, Magnus Borga, Mats Hammar, Olof Dahlqvist Leinhard
OBJECTIVES: To determine precision of magnetic resonance imaging (MRI) based fat and muscle quantification in a group of postmenopausal women. Furthermore, to extend the method to individual muscles relevant to upper-body exercise. MATERIALS AND METHODS: This was a sub-study to a randomized control trial investigating effects of resistance training to decrease hot flushes in postmenopausal women. Thirty-six women were included, mean age 56 ± 6 years. Each subject was scanned twice with a 3...
2018: PloS One
Seok Hahn, Young Han Lee, Jin-Suck Suh
OBJECTIVE: To compare the diagnostic performance of modified Dixon (mDxion) turbo spin echo (TSE) T2-weighted MRI and conventional T1-weighted MRI in vertebral metastasis detection. METHODS: Between September 2014 and October 2016, 33 patients with 68 metastases who had undergone whole-spine MRI were enrolled. The following sagittal image sets were evaluated: T1WI, and mDixon TSE T2-weighted water and fat images. Two radiologists independently evaluated each image-set for metastasis...
February 2, 2018: British Journal of Radiology
S Keller, Z J Wang, A Aigner, A C Kim, A Golsari, H Kooijman, G Adam, J Yamamura
PURPOSE: To compare the influence of two different regions of interest (ROIs) on diffusion tensor metrics in dystrophic thigh muscles using a custom-made (whole muscle) ROI including and a selective ROI excluding areas of fatty replacement. METHODS: Diffusion tensor imaging (DTI) and chemical-shift-encoded water-fat magnetic resonance imaging (MRI) of the thigh was conducted on a 3-Tesla system in 15 cases with muscular dystrophy and controls. The ROIs were chosen according to patterns of fatty replacement on co-registered axial DTI and gradient echo sequence (GRE) images...
February 1, 2018: Clinical Neuroradiology
Laura E Rupprecht, Alison D Kreisler, Samantha R Spierling, Giordano de Guglielmo, Marsida Kallupi, Olivier George, Eric C Donny, Eric P Zorrilla, Alan F Sved
RATIONALE: The ability of nicotine to suppress body weight is cited as a factor impacting smoking initiation and the failure to quit. Self-administered nicotine in male rats suppresses weight independent of food intake, suggesting that nicotine increases energy expenditure. OBJECTIVE: The current experiment evaluated the impact of self-administered nicotine on metabolism in rats using indirect calorimetry and body composition analysis. METHODS: Adult male rats with ad libitum access to powdered standard rodent chow self-administered intravenous infusions of nicotine (60 μg/kg/infusion or saline control) in daily 1-h sessions in the last hour of the light cycle...
January 21, 2018: Psychopharmacology
Ruo-Mi Guo, Qing-Ling Li, Zhong-Xing Luo, Wen Tang, Ju Jiao, Jin Wang, Zhuang Kang, Shao-Qiong Chen, Yong Zhang
Objective: To noninvasively assess the neurodegenerative changes in the brain of patients with Niemann-Pick type C (NPC) disease by measuring the lesion tissue with the iterative decomposition of water and fat with echo asymmetry and least square estimation-iron quantification (IDEAL-IQ). Materials and Methods: Routine brain MRI, IDEAL-IQ and 1H-proton magnetic resonance spectroscopy (1H-MRS, served as control) were performed on 12 patients with type C Niemann-Pick disease (4 males and 8 females; age range, 15-61 years; mean age, 36 years) and 20 healthy subjects (10 males and 10 females; age range, 20-65 years; mean age, 38 years)...
January 2018: Korean Journal of Radiology: Official Journal of the Korean Radiological Society
Gary V Martinez
Magnetic resonance imaging (MRI) is an imaging technique derived from radiofrequency (RF) signals of proton that are magnetized by a strong magnetic field. These protons typically originate from water, fat, or metabolites. The application of RF pulses is used to excite the magnetization, whereas pulsed magnetic field gradients are used to provide spatial localization. This chapter describes the fundamental principles giving rise to MR images. Furthermore, the connection between relaxation and image contrast is discussed...
2018: Methods in Molecular Biology
Vibha Singhal, Miriam A Bredella
Bone strength is affected not only by bone mineral density (BMD) and bone microarchitecture but also its microenvironment. Recent studies have focused on the role of marrow adipose tissue (MAT) in the pathogenesis of bone loss. Osteoblasts and adipocytes arise from a common mesenchymal stem cell within bone marrow and many osteoporotic states, including aging, medication use, immobility, over - and undernutrition are associated with increased marrow adiposity. Advancements in imaging technology allow the non-invasive quantification of MAT...
January 10, 2018: Bone
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"