Abstract:
:The aim of this study was to establish a rapid method for in vivo quantification of a large range of flow velocities using phase information. A basic gradient-echo sequence was constructed, in which flow was encoded along the slice selection direction by variation of the amplitude of a bipolar gradient without changes in sequence timings. The influence of field inhomogeneities and eddy currents was studied in a 1.5 T interleaved sequences for calibration and in vivo flow determination were constructed, and flow information was obtained by pairwise subtraction of velocity-encoded from velocity non-encoded phase images. Calibration was performed in a nongated mode using flow phantoms, and the results were compared with theoretically calculated encoding efficiencies. In vivo flow was studied in healthy volunteers in three different areas using cardiac gating; central blood flow in the great thoracic vessels, peripheral blood flow in the popliteal vessels, and flow of cerebrospinal fluid (CSF) in the cerebral aqueduct. The results show good agreement with results obtained with other techniques. The proposed method for flow determination was shown to be rapid and flexible, and we thus conclude that it seems well suited for routine clinical MR examinations.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Ståhlberg F,Mogelvang J,Thomsen C,Nordell B,Stubgaard M,Ericsson A,Sperber G,Greitz D,Larsson H,Henriksen Odoi
10.1016/0730-725x(89)90535-3subject
Has Abstract,Author List Incompletepub_date
1989-11-01 00:00:00pages
655-67issue
6eissn
0730-725Xissn
1873-5894pii
0730-725X(89)90535-3journal_volume
7pub_type
杂志文章abstract::The purpose of this study was to develop a novel intravascular loopless monopole antenna (ILMA) design specifically for imaging of small vessel walls. The ILMA consisted of an unshielded, low-friction guide wire and a tuning/matching box. The material of the guide wire was nitinol and it was coated with polyurethane. ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2012.06.032
更新日期:2013-01-01 00:00:00
abstract:PURPOSE:To evaluate non-invasive imaging biomarkers for assessing renal fibrosis. DWI is used to assess renal function; intravoxel incoherent motion (IVIM) provides additional measures of perfusion-related diffusion (D*, blood flow; f, perfusion fraction). We aim to determine if reduced ADC seen in renal fibrosis is at...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2015.07.012
更新日期:2015-12-01 00:00:00
abstract::Biexponential T(2) relaxation of the localized water signal can be used for segmentation of spectroscopic volumes. To assess the specificity of the components an iterative relaxation measurement of the localized water signal (STEAM, 12 echo times, geometric spacing from 30 ms to 2000 ms) was combined with magnetizatio...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(01)00396-4
更新日期:2001-07-01 00:00:00
abstract::Collagen fibers in tendons and entheses are highly ordered. The protons within the bound water are subject to dipolar interactions whose strength depends on the orientation of the fibers to the static magnetic field B(0). Clinical pulse sequences have been employed to investigate this magic angle effect of the Achille...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2008.09.003
更新日期:2009-05-01 00:00:00
abstract: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 chall...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2016.08.006
更新日期:2017-01-01 00:00:00
abstract::Today, patients with alveolar rhabdomyosarcoma have a favorable prognosis with a survival rate of more than 80%, due to modern radiotherapy. However, those patients with secondary meningeal involvement are still afflicted with a mortality rate of 90% unless a different therapeutic approach is taken. We report a case o...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(93)90035-c
更新日期:1993-01-01 00:00:00
abstract::The goal of this study was to develop and evaluate high-resolution magnetic resonance spectroscopic imaging (MRSI) utilizing the gains in signal-to-noise ratio (SNR) provided by combining higher magnetic field with high-sensitivity phased-array (PA) coils. We investigated the maximum improvement in spatial resolution ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2005.10.019
更新日期:2006-01-01 00:00:00
abstract::Percentage of lipid content of 22 adrenal cortex lesions and their water proton longitudinal relaxation time were measured in vitro at 60 MHz. Although water relaxation times obtained on benign and malignant samples overlap each other, measurements of the percentage of lipids performed on the same tissues allow us to ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(87)90123-8
更新日期:1987-01-01 00:00:00
abstract::Quantifying the intracranial tissue volume changes in magnetic resonance imaging (MRI) assists specialists to analyze the effects of natural or pathological changes. Since these changes can be subtle, the accuracy of the automatic compartmentalization method is always criticized by specialists. We propose and then eva...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2019.11.002
更新日期:2020-01-01 00:00:00
abstract::Measurements of arterial input function (AIF) can have large systematic errors at standard contrast agent doses in dynamic contrast enhanced MRI (DCE-MRI). We compared measured AIFs from low dose (AIFLD) and standard dose (AIFSD) contrast agent injections, as well as the AIF derived from a muscle reference tissue and ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2015.10.025
更新日期:2016-02-01 00:00:00
abstract:BACKGROUND AND PURPOSE:The widespread propagation of synchronized neuronal firing in seizure disorders may affect cortical and subcortical brain regions. Diffusion tensor imaging (DTI) can noninvasively quantify white matter integrity. The purpose of this study was to investigate the abnormal changes of white matter in...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2010.03.046
更新日期:2010-11-01 00:00:00
abstract::Gadolinium-based magnetic resonance (MR) contrast agents (GBCM) causes a devastating systemic fibrosing illness, nephrogenic systemic fibrosis (NSF), in patients with reduced kidney function. GBCM targets iron-recycling CD163- and ferroportin-expressing macrophages to release labile iron that mediates gadolinium toxic...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章,评审
doi:10.1016/j.mri.2016.08.016
更新日期:2016-12-01 00:00:00
abstract::Magnetic resonance imaging (MRI) has been used to characterize tissues in morphological studies. Here, 23Na NMR imaging was used to study the distribution in muscle of brine (5 M NaCl), injected before onset of rigor mortis. First, the distribution of brine was monitored in excised muscle from rabbits for 6 hr followi...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(94)92360-4
更新日期:1994-01-01 00:00:00
abstract::The subthalamic nucleus (STN) is one of the most common stimulation targets for treating Parkinson's disease using deep brain stimulation (DBS). This procedure requires precise placement of the stimulating electrode. Common practice of DBS implantation utilizes microelectrode recording to locate the sites with the cor...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2012.02.006
更新日期:2012-06-01 00:00:00
abstract:PURPOSE:To develop a RF coil system for joint imaging of intracranial and extracranial arterial vessel wall at 3T. MATERIALS AND METHOD:The coil system consists of a 24-channel head coil combined with an 8-channel carotid coil. It is compared with a standard coil configuration (12-channel head coil+4-channel neck coil...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2016.10.018
更新日期:2017-02-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Slice-encoding metal artifact corrections (SEMAC)-view-angle tilting (VAT) sequences have recently been used in clinical protocols to reduce metal artifacts in MR scans of patients with spinal instrumentation. The objective of this study was to compare the SEMAC-VAT sequence with the conventional...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2018.08.002
更新日期:2018-12-01 00:00:00
abstract::MRI reconstruction using super-resolution is presented and shown to improve spatial resolution in cases when spatially-selective RF pulses are used for localization. In 2-D multislice MRI, the resolution in the slice direction is often lower than the in-plane resolution. For certain diagnostic imaging applications, is...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(02)00511-8
更新日期:2002-06-01 00:00:00
abstract::We report on experiments to characterize internal magnetic field gradients that are caused by magnetic susceptibility differences between the solid phase and the fluids filling the pore space. Our measurements focus on low-field relaxometry of brine and oil in sandstones from various reservoirs around the world. Our r...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(01)00287-9
更新日期:2001-04-01 00:00:00
abstract::The most recently reported magnetic resonance first-pass myocardial perfusion studies were restricted to single slice imaging or a data analysis based on interactively placed regions of interest. This study was designed to investigate a new saturation recovery TurboFLASH sequence for multisection myocardial perfusion ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(98)00166-0
更新日期:1999-02-01 00:00:00
abstract::Echo planar imaging (EPI) was extended for the acquisition of both, the spin-echo (SE) and the stimulated echo in a stimulated echo sequence after one excitation from thermal equilibrium. The two independent EPI images reflect different states of the transverse magnetization excited and measured almost simultaneously....
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(94)91234-n
更新日期:1994-01-01 00:00:00
abstract::This paper presents a data-driven method for the reconstruction and visualisation of curvilinear slices from three-dimensional (3D) magnetic resonance (MR) scans of the head. Visualisation of curvilinear slices, rather than standard planar slices, produces symmetrical views of the cortex and allows small abnormalities...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(98)00132-5
更新日期:1998-12-01 00:00:00
abstract::Autoradiographic studies have shown that low dose ketamine produces increases in regional glucose utilisation and blood flow in the hippocampus, cerebral cortex, and olfactory lobe in the rat brain, probably due to antagonism at the NMDA receptor. Functional MRI using deoxyhaemoglobin contrast can be used to study cha...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(95)00010-e
更新日期:1995-01-01 00:00:00
abstract::NMR spectroscopy is applied to study microstructure of calcium silicate hydrates present in cement and concrete. It is shown that 29Si NMR gives information on the siliceous skeleton of the hydrates. 1H NMR, using CRAMPS techniques, allows to discriminate between protons linked to silicon atoms or to calcium atoms. A ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(96)00211-1
更新日期:1996-01-01 00:00:00
abstract::The fast Fourier flow technique offers a convenient way for extremely exact flow measurements. In combination with ECG gating, arterial flow can be studied. The total acquisition time for a single measurement is about 10 s, an ECG-gated cine sequence can be acquired in about 4 min. Fast Fourier flow can, therefore, be...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(88)90473-0
更新日期:1988-07-01 00:00:00
abstract::Brain vascular damage accumulate in aging and often manifest as white matter hyperintensities (WMHs) on MRI. Despite increased interest in automated methods to segment WMHs, a gold standard has not been achieved and their longitudinal reproducibility has been poorly investigated. The aim of present work is to evaluate...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2020.11.008
更新日期:2021-02-01 00:00:00
abstract::This study describes the appearance of Brenner tumors on MR imaging and compares quantitative signal intensity measurements of Brenner tumors with that of other ovarian tumors. A search of pathologic and MR records disclosed patients who had MRIs showing Brenner tumors prior to surgical excision. Patients (21) with ot...
journal_title:Magnetic resonance imaging
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1016/s0730-725x(98)00136-2
更新日期:1998-12-01 00:00:00
abstract::A new approach to solid-state imaging (SSI) is presented. The method relies on narrowing the resonance line using the Lee-Goldburg sequence. The technique is easy to implement in practice and may find widespread applications in materials science. ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(92)90409-s
更新日期:1992-01-01 00:00:00
abstract::Resting fluctuations in arterial CO2 (a cerebral vasodilator) are believed to be an important source of low-frequency blood oxygenation level dependent (BOLD) signal fluctuations. In this study we focus on the two commonly used resting-states in functional magnetic resonance imaging experiments, eyes open and eyes clo...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2012.06.013
更新日期:2013-04-01 00:00:00
abstract::Diffusion tensor magnetic resonance imaging (DTI) is useful for studying the microstructural changes in the spinal cord following traumatic injury; however, image quality is generally poor due to the small size of the spinal cord, physiological motion and susceptibility artifacts. Self-navigated, interleaved, variable...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2010.06.006
更新日期:2010-11-01 00:00:00
abstract::Dynamic contrast-enhanced magnetic resonance imaging (MRI) is widely used for measuring perfusion and blood volume, especially cerebral blood volume (CBV). In case of blood-brain barrier (BBB) disruption, the conventional techniques only partially determine the pharmacokinetic parameters of contrast medium (CM) exchan...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(00)00223-x
更新日期:2000-12-01 00:00:00