Abstract:
:The purpose of this study was to evaluate the diagnostic potential of a high-resolution magnetic resonance (MR) venography technique in patients with cerebral arteriovenous malformations (AVMs). A high-resolution 3D gradient echo sequence was used with a long echo time TE to obtain venous information down to sub-pixel sized vessel diameters of several hundred microns. The method is based on the paramagnetic property of deoxyhemoglobin, and the resulting developing phase difference between veins and brain parenchyma at long echo times which leads to signal cancellation. The reconstructed venograms were compared with time-of-flight (TOF)-MR angiography using qualitative and quantitative criteria with the conventional digital subtraction angiography serving as the reference gold standard. In 17 patients with angiographically proven cerebral AVMs, the method indicates its potential in clinical applications. Venography was able to detect all AVMs whereas TOF-MRA failed in three patients. In the delineation of venous drainage patterns MR venography was superior to TOF-MRA, however, the method failed in the detection of about half of the main feeding arteries, as expected. Due to susceptibility artifacts at air/tissue boundaries and interference with paramagnetic hemosiderin, venography was limited with respect to the delineation of the exact nidus sizes and shapes in ten patients with AVMs located close to the skull base or having suffered from previous bleeding. Although the visualization of draining veins represents an important prerequisite in the surgical and radiosurgical treatment planning of cerebral AVMs, application of high resolution MR venography may be limited in the diagnostic work-up in some of these patients. On the other hand, it may be of special importance in the early detection and assessment of small AVMs that are difficult to diagnose with other MR methods.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Essig M,Reichenbach JR,Schad LR,Schoenberg SO,Debus J,Kaiser WAdoi
10.1016/s0730-725x(99)00084-3subject
Has Abstractpub_date
1999-12-01 00:00:00pages
1417-25issue
10eissn
0730-725Xissn
1873-5894pii
S0730-725X(99)00084-3journal_volume
17pub_type
杂志文章abstract::It has previously been observed that during isometric dorsiflexion exercise, the time course of T2-weighted signal intensity (SI) changes is spatially heterogeneous. The purpose of this study was to test the hypothesis that this spatial heterogeneity would increase at higher contraction intensities. Eight subjects per...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2008.01.023
更新日期:2008-10-01 00:00:00
abstract::The functional value of TurboFLASH MR imaging in the assessment of dynamic contrast enhancement and renal perfusion anomalies was evaluated in seven patients, who also underwent renal scintigraphy in baseline conditions. The basal renograms obtained from MAG-3 scintigraphy (mercapto acetyl triglycine, MAG3-S) and from...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(94)92534-8
更新日期:1994-01-01 00:00:00
abstract::A dextran-Gd-DTPA compound has been recently synthesized utilizing 70,800 Da molecular weight dextran. This polymeric contrast agent for magnetic resonance imaging has been found chemically to be very stable and to demonstrate in vitro improved relaxivities of 1.5 to 2.3 times that of monomeric Gd-DTPA at 100 MHz. Thi...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(92)90515-2
更新日期:1992-01-01 00:00:00
abstract::A regularization strategy is described for generalized autocalibrating partially parallel acquisition (GRAPPA) that allows successful calibration using a small number of autocalibration signals (ACS). The approach requires certain nonlinear relationships between the GRAPPA coefficients to be satisfied, which increases...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2008.05.005
更新日期:2009-01-01 00:00:00
abstract::Measurements have been carried out in six subjects at magnetic fields of 1.5, 3 and 7 T, with the aim of characterizing the variation of T2* with field strength in human brain. Accurate measurement of T2* in the presence of macroscopic magnetic field inhomogeneity is problematic due to signal decay resulting from thro...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2007.02.014
更新日期:2007-07-01 00:00:00
abstract::Functional magnetic resonance imaging favors the use of multi-slice gradient-recalled echo-planar imaging due to its short image acquisition times, whole brain coverage and sensitivity to BOLD contrast. However, despite its advantages, gradient-recalled echo-planar imaging also is sensitive to static magnetic field gr...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(00)00199-5
更新日期:2000-11-01 00:00:00
abstract:PURPOSE:Diffusional kurtosis imaging (DKI) is sensitive to the effects of signal noise due to strong diffusion weightings and higher order modeling of the diffusion weighted signal. A simple noise correction scheme is proposed to remove the majority of the noise bias in the estimated diffusional kurtosis. METHODS:Weig...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2014.08.028
更新日期:2015-01-01 00:00:00
abstract:PURPOSE:To provide a single open-source platform for comprehensive MR algorithm development inclusive of simulations, pulse sequence design and deployment, reconstruction, and image analysis. METHODS:We integrated the "Pulseq" platform for vendor-independent pulse programming with Graphical Programming Interface (GPI)...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2018.03.008
更新日期:2018-10-01 00:00:00
abstract:PURPOSE:To develop a protocol to non-invasively measure and map fat fraction, fat/(fat+water), as a function of age in the adult thymus for future studies monitoring the effects of interventions aimed at promoting thymic rejuvenation and preservation of immunity in older adults. MATERIALS AND METHODS:Three-dimensional...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2018.03.016
更新日期:2018-07-01 00:00:00
abstract::We retrospectively compared the diagnostic accuracy of abdominal ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) studies performed on the same individual to determine the relative performance of these modalities in the evaluation of disease processes, arising from different intra-abdomi...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2003.01.001
更新日期:2004-01-01 00:00:00
abstract::We studied the effect of hydralazine on tumor blood volume fraction and microvascular random flow velocity magnitude by IVIM weighted MRI in conjunction with dynamic Gd-DTPA-Albumin enhanced MRI. Blood volume fraction maps were obtained from the dynamic Gd-DTPA-Albumin enhanced MRI measurements. The average blood volu...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(01)00431-3
更新日期:2001-10-01 00:00:00
abstract::An efficient method for obtaining longitudinal relaxation time (T1) maps is based on acquiring two spoiled gradient recalled echo (SPGR) images in steady states with different flip angles, which has also been extended, with additional acquisitions, to obtain a tissue water content (M0) map. Several factors, including ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2013.08.001
更新日期:2013-12-01 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:PURPOSE:To evaluate the reproducibility of quantitative diffusion measurements obtained with reduced Field of View (rFOV) and Multi-shot EPI (msEPI) acquisitions, using single-shot EPI (ssEPI) as a reference. METHODS:Diffusion phantom experiments, and prostate diffusion-weighted imaging in healthy volunteers and patie...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2018.04.006
更新日期:2018-09-01 00:00:00
abstract::In this work, magnetic resonance imaging (MRI) was employed to observe the in-situ formation and dissociation of methane hydrates in porous media. Methane hydrate was formed in a high-pressure cell with controlled temperature, and then the hydrate was dissociated by thermal injection. The process was photographed by t...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2014.12.010
更新日期:2015-05-01 00:00:00
abstract::The present study examined initial changes in non-traumatic osteonecrosis of the femoral head (ONF) on T1- and T2-weighted MR images, and fat suppression images. The subjects were 57 renal transplant recipients (37 males and 20 females), whose median age at the time of transplantation was 31.5 years old (range, 10 to ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(01)00424-6
更新日期:2001-09-01 00:00:00
abstract:OBJECTIVE:The pathological changes in Parkinson disease begin in the brainstem; reach the limbic system and ultimately spread to the cerebral cortex. In Parkinson disease (PD) patients, we evaluated the alteration of cingulate fibers, which comprise part of the limbic system, by using diffusional kurtosis imaging (DKI)...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2013.06.009
更新日期:2013-11-01 00:00:00
abstract::Most modern techniques for functional magnetic resonance imaging (fMRI) rely on blood-oxygen-level-dependent (BOLD) contrast as the basic principle for detecting neuronal activation. However, the measured BOLD effect depends on a transfer function related to neurophysiological changes accompanying electrical neural ac...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2008.02.006
更新日期:2008-11-01 00:00:00
abstract::The amplitudes of gradient-echoes produced using static field gradients are sensitive to diffusion of tissue water during the echo evolution time. Gradient-echoes have been used to produce MR images in which image intensity is proportional to the self-diffusion coefficient of water. However, such measurements are subj...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(95)00051-h
更新日期:1995-01-01 00:00:00
abstract::Functional MR (fMR) imaging techniques based on blood oxygenation level dependent (BOLD) effects were developed and applied to a rat brain tumor model to evaluate the potential utility of the method for characterizing tumor growth and regression following treatment. Rats bearing 9L brain tumors in situ were imaged dur...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(98)00208-2
更新日期:1999-05-01 00:00:00
abstract:OBJECTIVE:The purpose of this study was to analyze flow patterns in the pulmonary circulation of healthy volunteers by using 4D flow magnetic resonance imaging. MATERIALS AND METHODS:The study was approved by the local ethics committee and all subjects gave written informed consent. Eighteen volunteers underwent a 4D ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2012.06.036
更新日期:2013-02-01 00:00:00
abstract::In congenital diaphragmatic hernia (CDH), lung hypoplasia and secondary pulmonary hypertension are the major causes of death and severe disability. Based on new therapeutic strategies survival rates could be improved to up to 80%. However, after surgical repair of CDH, long-term follow-up of these pediatric patients i...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2015.08.003
更新日期:2015-12-01 00:00:00
abstract:PURPOSE:To evaluate the utility of fat fraction (FF) for the differentiation of different breast tissues and in various breast tumor subtypes using in vivo proton (1H) magnetic resonance spectroscopy (MRS). METHODS:1H MRS was performed on 68 malignant, 35 benign, and 30 healthy volunteers at 1.5 T. Malignant breast ti...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2018.02.004
更新日期:2018-06-01 00:00:00
abstract::Positive contrast imaging methods produce enhanced signal at large magnetic field gradient in magnetic resonance imaging. Several postprocessing algorithms, such as susceptibility gradient mapping and phase gradient mapping methods, have been applied for positive contrast generation to detect the cells targeted by sup...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2011.04.011
更新日期:2011-09-01 00:00:00
abstract::Stimulated spin-echo and Carr-Purcell pulse sequences, with pulsed magnetic field gradients, have been used to study the self-diffusion processes of the water in swollen and in supercoiled polyacrylamide gels and in polysaccharides agarose gels, for different polymer concentrations. Restricted diffusion effects are ev...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(96)00202-0
更新日期:1996-01-01 00:00:00
abstract:BACKGROUND:The molecular structure, charge, thermodynamic and kinetic stability are approximately the same for gadodiamide and gadoversetamide, the main substantive difference is that gadodiamide is manufactured with 5% free ligand to form Omniscan® and gadoversetamide with 10% free ligand to form OptiMARK®. PURPOSE:T...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2018.11.015
更新日期:2019-05-01 00:00:00
abstract::1H-nuclear magnetic resonance (NMR) measurements have been carried out on a banded sandstone to investigate the effects of structural inhomogeneities on the fluid dynamics of the sample as a whole. The results obtained from average propagator measurements (the probability of a displacement z in a time delta or P delta...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(98)00043-5
更新日期:1998-06-01 00:00:00
abstract::Deep brain stimulation (DBS) is used increasingly in the field of movement disorders. The implanted electrodes create not only a prior risk to patient safety during MRI, but also a unique opportunity in the collection of functional MRI data conditioned by direct neural stimulation. We evaluated MRI-related heating for...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2005.02.007
更新日期:2005-05-01 00:00:00
abstract::New applications of the NMR-MOUSE (mobile universal surface explorer) to non-destructive quality control of elastomers are reported. One example concern the thermal aging of fast clutches which was probed by measurements of 1H transverse relaxation time. Novel methodological developments show that 1H double-quantum fi...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(01)00277-6
更新日期:2001-04-01 00:00:00
abstract:OBJECTIVES:The objectives of this study were to develop protocols that measure abdominal fat and calf muscle lipids with magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS), respectively, at 3 T and to examine the correlation between these parameters and insulin sensitivity. MATERIALS AND METHOD...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2007.06.006
更新日期:2008-02-01 00:00:00