Abstract:
:Golgi impregnation is unique in its ability to display the dendritic trees and axons of large numbers of individual neurons by histology. Here we apply magnetic resonance microscopy to visualize the neuroanatomy of animal models by combining histologic fixation chemistry with paramagnetic contrast agents. Although there is some differential uptake of the standard small-molecular-weight contrast agents by different tissue types, detailed discrimination of tissue architecture in MR images does not approach that of standard histology. Our modified Golgi impregnation method significantly increases anatomic detail in magnetic resonance microscopy images. Fixed mouse brains were treated with a solution containing a paramagnetic contrast agent (gadoteridol) and potassium dichromate. Results demonstrate a specific contrast enhancement likely due to diamagnetic hexavalent chromium undergoing tissue specific reduction to paramagnetic trivalent chromium. This new method dramatically improves neuroanatomical contrast compared to conventional fixation, displaying detail approximating that of histologic specimens at low (4x) magnification.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Zhang X,Bearer EL,Perles-Barbacaru AT,Jacobs REdoi
10.1002/mrm.22322subject
Has Abstractpub_date
2010-05-01 00:00:00pages
1391-7issue
5eissn
0740-3194issn
1522-2594journal_volume
63pub_type
杂志文章abstract::Cerebral blood volume changes with arterial carbon dioxide were monitored by proton T1-weighted MR images following administration of the intravascular contrast agent Gd-DTPA labeled with human serum albumin. Without MR contrast, no significant image intensity changes were observed with PaCO2. Following contrast, regi...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910230104
更新日期:1992-01-01 00:00:00
abstract::Echo-planar spectroscopic imaging (EPSI) can be used for fast spectroscopic imaging of water and fat resonances at high resolution to improve structural and functional imaging. Because of the use of oscillating gradients during the free induction decay (FID), spectra obtained with EPSI are often degraded by Nyquist gh...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.10485
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abstract::A new volume selection/spectral editing pulse sequence (VOSING) is presented. The features specific to the technique are that the volume selection and the editing intervals coincide and that no decoupling is necessary. The pulse sequence can be applied under both homo- and heteronuclear conditions. Phantom experiments...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910080108
更新日期:1988-09-01 00:00:00
abstract::The fast spin-echo (FSE) sequence is frequently used as a fast data-readout technique in conjunction with other pulse sequence elements, such as in fluid-attenuated inversion-recovery (FLAIR) and double inversion-recovery (DIR) sequences. In order to implement those pulse sequences, an understanding is required of how...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.20541
更新日期:2005-07-01 00:00:00
abstract::In in vivo phosphorus magnetic resonance spectroscopy (MRS), spectroscopic imaging (SI) can be used as a flexible localization technique, producing spectra from multiple volumes in a single examination. Presented here are phosphorus SI studies of human organs in which a selective-volume SI reconstruction was used rath...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910120302
更新日期:1989-12-01 00:00:00
abstract::Atherosclerosis initially develops predominantly at the aortic root and carotid origin, where effective visualization in mice requires efficient cardiac and respiratory gating. The present study sought to first compare the high-resolution MRI gating performance of two digital gating strategies using: 1) separate cardi...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21308
更新日期:2007-12-01 00:00:00
abstract::Functional MR imaging (fMRI) of activation in the brain is one of the more demanding applications required of an NMR imaging instrument. Since the signal changes in activation imaging are quite small, any instrumental variations can easily compromise the fMRI contrast. The authors describe a simple method for measurin...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910360422
更新日期:1996-10-01 00:00:00
abstract:PURPOSE:To assess the blood-tissue distribution of hyperpolarized (13) C-labeled molecules in vivo. METHODS:Spin-echo experiments with simultaneous acquisition of the free induction decay (FID) signal following the excitation pulse and the spin-echo signal, were used to monitor hyperpolarized [1-(13) C]lactate, [1-(13...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.24591
更新日期:2013-11-01 00:00:00
abstract::A simple theoretical model was developed to compare the sensitivities (i.e., signal-to-noise ratios per unit imaging time) of two-dimensional (2D) multislice and 3D imaging sequences. The model shows that the sensitivities of 3D and 2D multislice MRI sequences are usually similar. Sensitivities are identical in T2-wei...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1522-2594(199904)41:4<824::aid-mrm23
更新日期:1999-04-01 00:00:00
abstract:PURPOSE:Proof-of-concept study of mapping renal blood flow vector field according to the inverse solution to a mass transport model of time resolved tracer-labeled MRI data. THEORY AND METHODS:To determine tissue perfusion according to the underlying physics of spatiotemporal tracer concentration variation, the mass t...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.28584
更新日期:2021-04-01 00:00:00
abstract::An implementation is reported of an imaging method to obtain MUltiple Resolutions along Phase-encode and Slice-select dimensions (MURPS), which enables dynamic imaging of focal changes using a graded, multiresolution approach. MURPS allows one to trade spatial resolution in part of the volume for improved temporal res...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1126
更新日期:2001-06-01 00:00:00
abstract::In this study, a spin- and gradient-echo echo-planar imaging (SAGE EPI) MRI pulse sequence is presented that allows simultaneous measurements of gradient-echo and spin-echo dynamic susceptibility-contrast perfusion-weighted imaging data. Following signal excitation, five readout trains were acquired using spin- and gr...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.23195
更新日期:2012-07-01 00:00:00
abstract::For patients with impaired breath-hold capacity and/or arrhythmias, real-time cine MRI may be more clinically useful than breath-hold cine MRI. However, commercially available real-time cine MRI methods using parallel imaging typically yield relatively poor spatio-temporal resolution due to their low image acquisition...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.24440
更新日期:2013-07-01 00:00:00
abstract:PURPOSE:Lung pO2 mapping with (3)He MRI assumes that the sources of signal decay with time during a breath-hold are radiofrequency depolarization and oxygen-dependent T1 relaxation, but the method is sensitive to other sources of spatio-temporal signal change such as diffusion. The purpose of this work was to assess th...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.24779
更新日期:2014-03-01 00:00:00
abstract::Slowly cycling cells are believed to play a critical role in tumor progression and metastatic dissemination. The goal of this study was to develop a method for in vivo detection of slowly cycling cells. To distinguish these cells from more rapidly proliferating cells that constitute the vast majority of cells in tumor...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.22917
更新日期:2011-11-01 00:00:00
abstract:PURPOSE:To develop and test real-time MR elastography for viscoelastic parameter quantification in skeletal muscle during dynamic exercises. METHODS:In 15 healthy participants, 6 groups of lower-leg muscles (tibialis anterior, tibialis posterior, peroneus, extensor digitorum longus, soleus, gastrocnemius) were investi...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.28095
更新日期:2020-07-01 00:00:00
abstract:PURPOSE:Direct mapping of neuronal currents using MRI would have fundamental impacts on brain functional imaging. Previous reports indicated that the stimulus-induced rotary saturation (SIRS) mechanism had the best potential of direct detection of neural oscillations; however, it lacked the high-sensitivity level neede...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25553
更新日期:2016-02-01 00:00:00
abstract:PURPOSE:To develop a rapid imaging framework for balanced steady-state free precession (bSSFP) that jointly reconstructs undersampled data (by a factor of R) across multiple coils (D) and multiple acquisitions (N). To devise a multi-acquisition coil compression technique for improved computational efficiency. METHODS:...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26902
更新日期:2018-05-01 00:00:00
abstract:PURPOSE:To optimize radiofrequency (RF) pulses for the selective excitation of dissolved phase (129)Xe that take into account the very short T2*, while simultaneously, minimally exciting the much larger gas signal. METHODS:Numerical simulations of Shinnar le-Roux pulses and binomial coefficient composite-element pulse...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25089
更新日期:2015-01-01 00:00:00
abstract:PURPOSE:Vulnerable atherosclerotic plaques are structurally weak and prone to rupture, presumably due to local oxidative stress. Redox active iron is linked to oxidative stress and the aim of this study was to investigate the distribution of Fe(III) in carotid plaques and its relation to vulnerability for rupture. MET...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.24687
更新日期:2014-02-01 00:00:00
abstract::A single breath-hold 3D cardiac phase resolved steady-state free precession (SSFP) sequence was developed, allowing 3D visualization of the moving coronary arteries. A 3D stack of spirals was acquired continuously throughout the cardiac cycle, and a sliding window reconstruction was used to achieve high temporal resol...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21365
更新日期:2007-09-01 00:00:00
abstract:PURPOSE:To develop a flexible fast spin echo (FSE) triple-echo Dixon (FTED) technique. METHODS:An FSE pulse sequence was modified by replacing each readout gradient with three fast-switching bipolar readout gradients with minimal interecho dead time. The corresponding three echoes were used to generate three raw image...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26186
更新日期:2017-03-01 00:00:00
abstract::Proton-observed carbon-edited (POCE) NMR spectroscopy is commonly used to measure 13C labeling with higher sensitivity compared to direct 13C NMR spectroscopy, at the expense of spectral resolution. For weakly coupled first-order spin systems, the multiplet signal at a specific proton chemical shift in POCE spectra di...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.20764
更新日期:2006-02-01 00:00:00
abstract::A previously developed eigenvector formalism is adapted to off-resonance in the transient response of quasiperiodic steady-state free precession (SSFP) sequences, including TrueFISP as a special case. The effective relaxation rates for essentially parallel and perpendicular deviations from the steady state are determi...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.20173
更新日期:2004-08-01 00:00:00
abstract:PURPOSE:Parameter mapping in sodium MRI data is challenging due to inherently low SNR and spatial resolution, prompting the need to employ robust models and estimation techniques. This work aims to develop a continuum model of sodium T 2 ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.27659
更新日期:2019-06-01 00:00:00
abstract::Specialized receiver coils having a small sensitive region can provide an improvement in SNR for MR imaging and spectroscopy, at the expense of limiting the usable field of view. This work presents a technique for designing coil arrays that allows the size and location of the sensitive region to be selected remotely. ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910170128
更新日期:1991-01-01 00:00:00
abstract:PURPOSE:To investigate for the first time the feasibility of aortic four-dimensional (4D) flow at 7T, both contrast enhanced (CE) and non-CE. To quantify the signal-to-noise ratio (SNR) in aortic 4D flow as a function of field strength and CE with gadobenate dimeglumine (MultiHance). METHODS:Six healthy male volunteer...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25317
更新日期:2015-05-01 00:00:00
abstract:PURPOSE:To systematically evaluate the dependence of intravoxel-incoherent-motion (IVIM) parameters on the b-value threshold separating the perfusion and diffusion compartment, and to implement and test an algorithm for the standardized computation of this threshold. METHODS:Diffusion weighted images of the upper abdo...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25506
更新日期:2015-11-01 00:00:00
abstract::Keyhole acquisition techniques have been used to reduce image acquisition times primarily in contrast agent studies and via simulation in interventional MRI procedures. More recent simulations have suggested that improved definition of an interventional device [e.g., biopsy needles, radio frequency (RF) electrodes] co...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1522-2594(199909)42:3<554::aid-mrm18
更新日期:1999-09-01 00:00:00
abstract::How stem cells promote myocardial repair in myocardial infarction (MI) is not well understood. The purpose of this study was to noninvasively monitor and quantify mesenchymal stem cells (MSC) from bone marrow to MI sites using magnetic resonance imaging (MRI). MSC were dual-labeled with an enhanced green fluorescent p...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.22735
更新日期:2011-05-01 00:00:00