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T1 mapping

Jia-Yang Li, Qi-Rong Zou, Xue-Mei Peng
OBJECTIVE: To compare the pharmacokinetics of cisatracurium between normal weight patients and morbidly obese patients. METHODS: Twelve obese ASA I-II patients (BMI≥35 kg/m(2)) undergoing laparoscopic Roux-en-Y gastric bypass and 12 normal weight ASA I-II patients (BMI of 18.5-24 kg/m(2)) undergoing laparoscopic surgery were enrolled. The obese patients were given a cisatracurium dose of 0.15 mg/kg according to the fat-free mass (FFM), and the non-obese patients received a dose of 0...
October 20, 2016: Nan Fang Yi Ke da Xue Xue Bao, Journal of Southern Medical University
Hongyoon Choi, Kyong Hwan Jin
BACKGROUND: Automated segmentation of brain structures is an important task in structural and functional image analysis. We developed a fast and accurate method for the striatum segmentation using deep convolutional neural networks (CNN). NEW METHOD: T1 magnetic resonance (MR) images were used for our CNN-based segmentation, which require neither image feature extraction nor nonlinear transformation. We employed two serial CNN, Global and Local CNN: The Global CNN determined approximate locations of the striatum...
October 21, 2016: Journal of Neuroscience Methods
Roberto Sanz-Requena, Luis Martí-Bonmatí, Rosario Pérez-Martínez, Gracián García-Martí
PURPOSE: The aim of this work is to establish normality and tumor tissue ranges for perfusion parameters from dynamic contrast-enhanced (DCE) MR of the peripheral prostate at 3T and to compare the diagnostic performance of quantitative and semi-quantitative parameters. MATERIALS AND METHODS: Thirty-six patients with prostate carcinomas (18 Gleason-6, 15 Gleason-7, and 3 Gleason-8) and 33 healthy subjects were included. Image analysis workflow comprised four steps: manual segmentation of whole prostate and lesions, series registration, voxelwise T1 mapping and calculation of pharmacokinetic and semi-quantitative parameters...
November 2016: European Journal of Radiology
Alexis Klengel, Patrick Stumpp, Steffen Klengel, Ina Böttger, Nadja Rönisch, Thomas Kahn
Purpose To compare single-shot echo-planar diffusion-weighted imaging-derived apparent diffusion coefficient (ADC) maps with fat-saturated (FS) proton density (PD)-weighted turbo spin-echo (TSE) imaging in the detection of bone marrow lesions (BMLs) after knee trauma. Materials and Methods Institutional review board approval was obtained from Leipzig University. Written informed consent was waived. Three radiologists retrospectively re-examined 97 consecutive patients with reported knee trauma who underwent 1...
October 24, 2016: Radiology
Mark N Wallace, Matthew J Cronin, Richard W Bowtell, Ian S Scott, Alan R Palmer, Penny A Gowland
Functional magnetic resonance imaging (fMRI) studies of the auditory region of the temporal lobe would benefit from the availability of image contrast that allowed direct identification of the primary auditory cortex, as this region cannot be accurately located using gyral landmarks alone. Previous work has suggested that the primary area can be identified in magnetic resonance (MR) images because of its relatively high myelin content. However, MR images are also affected by the iron content of the tissue and in this study we sought to confirm that different MR image contrasts did correlate with the myelin content in the gray matter and were not primarily affected by iron content as is the case in the primary visual and somatosensory areas...
2016: Frontiers in Neuroscience
J M Shiguetomi-Medina, J L Ramirez-Gl, H Stødkilde-Jørgensen, B Møller-Madsen
BACKGROUND: Up to 80 % of cartilage is water; the rest is collagen fibers and proteoglycans. Magnetic resonance (MR) T1-weighted measurements can be employed to calculate the water content of a tissue using T1 mapping. In this study, a method that translates T1 values into water content data was tested statistically. MATERIALS AND METHODS: To develop a predictive equation, T1 values were obtained for tissue-mimicking gelatin samples. 1.5 T MRI was performed using inverse angle phase and an inverse sequence at 37 (±0...
October 22, 2016: Journal of Orthopaedics and Traumatology: Official Journal of the Italian Society of Orthopaedics and Traumatology
Ananth Kidambi, Manish Motwani, Akhlaque Uddin, David P Ripley, Adam K McDiarmid, Peter P Swoboda, David A Broadbent, Tarique Al Musa, Bara Erhayiem, Joshua Leader, Pierre Croisille, Patrick Clarysse, John P Greenwood, Sven Plein
OBJECTIVES: In the setting of reperfused acute myocardial infarction (AMI), the authors sought to compare prediction of contractile recovery by infarct extracellular volume (ECV), as measured by T1-mapping cardiac magnetic resonance (CMR), with late gadolinium enhancement (LGE) transmural extent. BACKGROUND: The transmural extent of myocardial infarction as assessed by LGE CMR is a strong predictor of functional recovery, but accuracy of the technique may be reduced in AMI...
October 18, 2016: JACC. Cardiovascular Imaging
Takashi Hashido, Shigeyoshi Saito
PURPOSE: Neuromelanin is a dark pigment granule present within certain catecholamine neurons of the human brain. Here, we aimed to clarify the relationship between contrast of neuromelanin-sensitive magnetic resonance imaging (MRI) and MR relaxation times using T1, T2, and T2* mapping of the lower midbrain. METHODS: The subjects were 14 healthy volunteers (11 men and 3 women, mean age 29.9 ± 6.9 years). Neuromelanin-sensitive MRI was acquired using an optimized T1-weighted two-dimensional (2D)-turbo spin-echo sequence...
2016: PloS One
Grzegorz Bauman, Francesco Santini, Orso Pusterla, Oliver Bieri
PURPOSE: To present a technique for simultaneous mapping of T1 , T2 , and relative spin density (M0 ) in human lung using inversion recovery ultra-fast steady-state free precession (IR-ufSSFP) imaging. METHODS: Pulmonary relaxometry with IR-ufSSFP is based on an interleaved time series acquisition of 2D images acquired at 1.5T. The technique was tested in a phantom and in four healthy volunteers using breath-hold and electrocardiogram triggering. Typically, 30 transient state images were acquired in a single breath-hold within < 10 s...
October 19, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Xiaoqing Wang, Arun A Joseph, Oleksandr Kalentev, K Dietmar Merboldt, Dirk Voit, Volkert B Roeloffs, Maaike van Zalk, Jens Frahm
OBJECTIVE: To develop a novel method for rapid myocardial T1 mapping at high spatial resolution. METHODS: The proposed strategy represents a single-shot inversion-recovery (IR) experiment triggered to early diastole during a brief breathhold. The measurement combines an adiabatic inversion pulse with a real-time readout by highly undersampled radial FLASH, iterative image reconstruction and T1 fitting with automatic deletion of systolic frames. The method was implemented on a 3 T MRI system using a GPU-equipped bypass computer for online application...
October 19, 2016: British Journal of Radiology
Eider M Arenaza-Urquijo, Robin de Flores, Julie Gonneaud, Miranka Wirth, Valentin Ourry, William Callewaert, Brigitte Landeau, Stéphanie Egret, Florence Mézenge, Béatrice Desgranges, Gaël Chételat
Engagement in cognitive activity (CA) and physical activity (PA) during the lifespan may counteract brain atrophy later in life. Here, we investigated engagement in CA and PA during late adulthood in association with gray matter volume (GM) in normal older adults, with special focus on the hippocampus. Forty-five cognitively normal older individuals (mean age: 72) underwent T1-weighted MRI and self-reported CA and PA assessment. Whole brain voxel-wise multiple regression models were carried out to assess the relationships between CA, PA and GM volume adjusted by age and sex...
October 18, 2016: Brain Imaging and Behavior
Martina F Callaghan, Siawoosh Mohammadi, Nikolaus Weiskopf
Quantitative MRI (qMRI) provides standardized measures of specific physical parameters that are sensitive to the underlying tissue microstructure and are a first step towards achieving maps of biologically relevant metrics through in vivo histology using MRI. Recently proposed models have described the interdependence of qMRI parameters. Combining such models with the concept of image synthesis points towards a novel approach to synthetic qMRI, in which maps of fundamentally different physical properties are constructed through the use of biophysical models...
October 18, 2016: NMR in Biomedicine
Yuko Y Inoue, Bharath Ambale-Venkatesh, Nathan Mewton, Gustavo J Volpe, Yoshiaki Ohyama, Ravi K Sharma, Colin O Wu, Chia-Ying Liu, David A Bluemke, Elsayed Z Soliman, João A C Lima, Hiroshi Ashikaga
Purpose To examine the associations of myocardial diffuse fibrosis and scar with surface electrocardiographic (ECG) parameters in individuals free of prior coronary heart disease in four different ethnicities. Materials and Methods This prospective cross-sectional study was approved by the institutional review boards, and all participants gave informed consent. A total of 1669 participants in the Multi-Ethnic Study of Atherosclerosis, or MESA, who were free of prior myocardial infarction underwent both ECG and cardiac magnetic resonance imaging...
October 13, 2016: Radiology
Hadi Fayad, Holger Schmidt, Thomas Kuestner, Dimitris Visvikis
: Respiratory motion may reduce accuracy in fusion of functional and anatomical images using combined Positron emission tomography / Magnetic resonance (PET/MR) systems. Methodologies for the correction of respiratory motion in PET acquisitions using such systems are mostly based on the use of respiratory synchronized MR acquisitions to derive motion fields. Existing approaches based on tagging acquisitions may introduce artifacts in the MR images, while motion model approaches require the acquisition of training datasets...
October 13, 2016: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
Sofya Kulikova, Lucie Hertz-Pannier, Ghislaine Dehaene-Lambertz, Cyril Poupon, Jessica Dubois
The volume fraction of water related to myelin (fmy) is a promising MRI index for in vivo assessment of brain myelination, that can be derived from multi-component analysis of T1 and T2 relaxometry signals. However, existing quantification methods require rather long acquisition and/or post-processing times, making implementation difficult both in research studies on healthy unsedated children and in clinical examinations. The goal of this work was to propose a novel strategy for fmy quantification within acceptable acquisition and post-processing times...
2016: PloS One
Jeremy W Gordon, Eugene Milshteyn, Irene Marco-Rius, Michael Ohliger, Daniel B Vigneron, Peder E Z Larson
PURPOSE: The purpose of this work was to explore the impact of slice profile effects on apparent diffusion coefficient (ADC) mapping of hyperpolarized (HP) substrates. METHODS: Slice profile effects were simulated using a Gaussian radiofrequency (RF) pulse with a variety of flip angle schedules and b-value ordering schemes. A long T1 water phantom was used to validate the simulation results, and ADC mapping of HP [(13) C,(15) N2 ]urea was performed on the murine liver to assess these effects in vivo...
October 13, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Agnes Mayr, Daniel Kitterer, Joerg Latus, Hannah Steubing, Joerg Henes, Francesco Vecchio, Philipp Kaesemann, Alexandru Patrascu, Andreas Greiser, Stefan Groeninger, Niko Braun, M Dominik Alscher, Udo Sechtem, Heiko Mahrholdt, Simon Greulich
BACKGROUND: Severe arrhythmias or heart failure may be surrogates of myocardial involvement in patients with connective tissue disorders (CTD). However, most patients present with unspecific symptoms, normal ECG, and preserved left ventricular ejection fraction (LV-EF). Therefore, timely diagnosis by an accurate technique is crucial. Late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) has proven value for the detection of focal processes, but due to the often diffuse character of fibrosis/inflammation in CTD patients, CMR mapping techniques might be of incremental value for the assessment of myocardial involvement...
October 13, 2016: Journal of Cardiovascular Magnetic Resonance
Hosung Kim, Ji-Hoon Kim, Katherine L Possin, Joseph Winer, Michael D Geschwind, Duan Xu, Christopher P Hess
In patients with premotor Huntington's disease (pmHD), literature has reported decreases in caudate volume. However, the regional vulnerability of the caudate nucleus to pmHD remains to be clarified. We aimed to determine whether regional structural damage of the caudate nucleus was present in pmHD and was correlated with clinical profile using a surface-based morphometric technique applied to T1-weighted MRI. The study cohort consisted of 14 volunteers with genetically confirmed pmHD (6 males; 41.8 ± 13...
October 11, 2016: Brain Imaging and Behavior
Jidan Zhong, David Q Chen, Matthew Walker, Adam Waspe, Thomas Looi, Karolina Piorkowska, James M Drake, Mojgan Hodaie
An increasing number of applications use the postnatal piglet model in neuroimaging studies, however, these are based primarily on T1 weighted image templates. There is a growing need for a multimodal structural brain template for a comprehensive depiction of the piglet brain, particularly given the growing applications of diffusion weighted imaging for characterizing tissue microstructures and white matter organization. In this study, we present the first multimodal piglet structural brain template which includes a T1 weighted image with tissue segmentation probability maps, diffusion weighted metric templates with multiple diffusivity maps, and population-based whole-brain fiber tracts for postnatal piglets...
2016: Frontiers in Neuroanatomy
Mustapha Bouhrara, Richard G Spencer
A number of central nervous system (CNS) diseases exhibit changes in myelin content and magnetic resonance longitudinal, T1, and transverse, T2, relaxation times, which therefore represent important biomarkers of CNS pathology. Among the methods applied for measurement of myelin water fraction (MWF) and relaxation times, the multicomponent driven equilibrium single pulse observation of T1 and T2 (mcDESPOT) approach is of particular interest. mcDESPOT permits whole brain mapping of multicomponent T1 and T2, with data acquisition accomplished within a clinically realistic acquisition time...
October 8, 2016: NeuroImage
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