Abstract:
PURPOSE:Cardiac T1 mapping has become an increasingly important imaging technique, contributing novel diagnostic options. However, currently utilized methods are often associated with accuracy problems because of heart rate variations and cardiac arrhythmia, limiting their value in clinical routine. This study aimed to introduce an improved arrhythmia-related robust T1 mapping sequence called RT-TRASSI (real-time Triggered RAdial Single-Shot Inversion recovery). METHODS:All measurements were performed on a 3.0T whole-body imaging system. A real-time feedback algorithm for arrhythmia detection was implemented into the previously described pulse sequence. A programmable motion phantom was constructed and measurements with different simulated arrhythmias arranged. T1 mapping accuracy and susceptibility to artifacts were analyzed. In addition, in vivo measurements and comparisons with 3 prevailing T1 mapping sequences (MOLLI, ShMOLLI, and SASHA) were carried out to investigate the occurrence of artifacts. RESULTS:In the motion phantom measurements, RT-TRASSI showed excellent agreement with predetermined reference T1 values. Percentage scattering of the T1 values ranged from -0.6% to +1.9% in sinus rhythm and -1.0% to +3.1% for high-grade arrhythmias. In vivo, RT-TRASSI showed diagnostic image quality with only 6% of the acquired T1 maps including image artifacts. In contrast, more than 40% of the T1 maps acquired with MOLLI, ShMOLLI, or SASHA included motion artifacts. CONCLUSION:Accuracy issues because of heart rate variability and arrhythmia are a prevailing problem in current cardiac T1 mapping techniques. With RT-TRASSI, artifacts can be minimized because of the short acquisition time and effective real-time feedback, avoiding potential data acquisition during systolic heart phase.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Gensler D,Salinger T,Düring M,Lorenz K,Jahns R,Wech T,Frantz S,Ertl G,Jakob PM,Nordbeck Pdoi
10.1002/mrm.27526subject
Has Abstractpub_date
2019-03-01 00:00:00pages
1714-1725issue
3eissn
0740-3194issn
1522-2594journal_volume
81pub_type
杂志文章abstract::The harmonic phase (HARP) method provides automatic and rapid analysis of tagged magnetic resonance (MR) images for quantification and visualization of myocardial strain. In this article, the development and implementation of a pulse sequence that acquires HARP images in real time are described. In this pulse sequence...
journal_title:Magnetic resonance in medicine
pub_type: 临床试验,杂志文章
doi:10.1002/mrm.10509
更新日期:2003-07-01 00:00:00
abstract::The accurate assessment of pulmonary perfusion is especially important in the evaluation of patients with suspected pulmonary embolism, a common and potentially lethal disorder that can be treated by aggressive anticoagulation. In this study, we demonstrate for the first time the use of MR to image pulmonary perfusion...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910360402
更新日期:1996-10-01 00:00:00
abstract:PURPOSE:A MR thermometry (MRT) method with field monitoring is proposed to improve the measurement of small temperature variations induced in brain MRI exams. METHODS:MR thermometry experiments were performed at 7 Tesla with concurrent field monitoring and RF heating. Images were reconstructed with nominal k-space tra...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.28501
更新日期:2021-03-01 00:00:00
abstract::The hypothesis was tested that the intravoxel distribution of water diffusion rates, as measured with a stretched-exponential model of diffusion-weighted imaging (DWI), is a marker of brain tumor invasion. Eight rats underwent intracerebral inoculation of C6 glioma cells. In three rats, cells were labeled with a fluor...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.20286
更新日期:2004-11-01 00:00:00
abstract:PURPOSE:Accurate characterization of contrast reagent (CR) longitudinal relaxivity in whole blood is required to predict arterial signal intensity in contrast-enhanced MR angiography (CE-MRA). This study measured the longitudinal relaxation rate constants (R1 ) over a concentration range for non-protein-binding and pro...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25064
更新日期:2014-12-01 00:00:00
abstract::A multimodal MR study including relaxometry, diffusion tensor imaging (DTI), and MR spectroscopy was performed on patients with classical phenylketonuria (PKU) and matched controls, to improve our understanding of white matter (WM) lesions. Relaxometry yields information on myelin loss or malformation and may substant...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21422
更新日期:2007-12-01 00:00:00
abstract::A simple (2)H NMR method for quantifying absolute (2)H-enrichments in all seven aliphatic positions of glucose following its derivatization to monoacetone glucose is presented. The method is based on the addition of a small quantity of (2)H-enriched formate to the NMR sample. When the method was applied to [2-(2)H]mon...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.10234
更新日期:2002-09-01 00:00:00
abstract::Since contrast in magnetic resonance imaging (MRI) is so sensitive to the magnetic relaxation rates of tissue protons, the use of paramagnetic ions to alter contrast in a tissue-specific fashion is an alluring prospect. The influence of these ions on the proton relaxation rates in homogeneous solutions is known to var...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910020206
更新日期:1985-04-01 00:00:00
abstract:PURPOSE:Within multiple sclerosis (MS) lesions iron is present in chronically activated microglia. Thus, iron detection with MRI might provide a biomarker for chronic inflammation within lesions. Here, we examine contributions of iron and myelin to magnetic susceptibility of lesions on quantitative susceptibility mappi...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25420
更新日期:2015-08-01 00:00:00
abstract:PURPOSE:To present a time-efficient technique for banding reduction in balanced steady-state free precession (bSSFP) imaging using phase-cycled simultaneous multislice (SMS) acquisition with CAIPIRINHA (controlled aliasing in parallel imaging results in higher acceleration). THEORY:The proposed technique exploits the ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26076
更新日期:2016-12-01 00:00:00
abstract:PURPOSE:To examine the detection sensitivity for the rapidly exchanging hydroxyl protons of D-glucose using the recently developed on-resonance variable delay multi-pulse (onVDMP) chemical exchange saturation transfer (CEST) technique. METHODS:The onVDMP method was applied for the detection of water signal changes upo...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.27364
更新日期:2019-01-01 00:00:00
abstract::Direct measurement of neural currents by means of MRI can potentially open a high temporal resolution (10-100 ms) window applicable for monitoring dynamics of neuronal activity without loss of the high spatial resolution afforded by MRI. Previously, we have shown that the alternating balanced steady state imaging affo...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.23105
更新日期:2012-05-01 00:00:00
abstract:PURPOSE:To develop a 256-channel dense-array electroencephalography (dEEG) sensor net (the Ink-Net) using high-resistance polymer thick film (PTF) technology to improve safety and data quality during simultaneous dEEG/MRI. METHODS:Heating safety was assessed with temperature measurements in an anthropomorphic head pha...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26116
更新日期:2017-02-01 00:00:00
abstract::In the pulsed arterial spin labeling (ASL) techniques EPISTAR, PICORE, and FAIR, subtraction of two images in which inflowing blood is first tagged and then not tagged yields a qualitative map of perfusion. An important reason this map is not quantitative is that there is a spatially varying delay in the transit of bl...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910390506
更新日期:1998-05-01 00:00:00
abstract:PURPOSE:To develop and evaluate a novel dynamic contrast-enhanced imaging technique called RACER-GRASP (Respiratory-weighted, Aortic Contrast Enhancement-guided and coil-unstReaking Golden-angle RAdial Sparse Parallel) MRI that extends GRASP to include automatic contrast bolus timing, respiratory motion compensation, a...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.27002
更新日期:2018-07-01 00:00:00
abstract::A technique for noninvasively quantifying the concentration of sodium ((23) Na) ions was applied to the study of ischemic stroke. (23) Na-magnetic resonance imaging techniques have shown considerable potential for measuring subtle changes in ischemic tissue, although studies to date have suffered primarily from poor s...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.23031
更新日期:2012-03-01 00:00:00
abstract::Diffusion-weighted single voxel experiments conducted at b-values up to 1 x 10(4) smm-2 yielded biexponential signal attenuation curves for both normal and ischemic brain. The relative fractions of the rapidly and slowly decaying components (f1, f2) are f1 = 0.80 +/- 0.02, f2 = 0.17 +/- 0.02 in healthy adult rat brain...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910360607
更新日期:1996-12-01 00:00:00
abstract::The diffusional kurtosis is an indicator for diffusion restrictions in biological tissue. It is observed experimentally that the kurtosis is largest for directions perpendicular to the fiber direction in white matter. The directional dependence of the kurtosis can be described by the diffusion kurtosis tensor. Since t...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.23133
更新日期:2012-05-01 00:00:00
abstract:PURPOSE:To develop a novel analytical method for quantification of chemical exchange saturation transfer (CEST) in the transient state. The proposed method aims to reduce the effects of non-chemical-exchange (non-CE) parameters on the CEST signal, emphasizing the effect of chemical exchange. METHODS:The difference in ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26559
更新日期:2017-11-01 00:00:00
abstract:PURPOSE:The diseased myocardium lacks metabolic flexibility and responds to stimuli differently compared with healthy hearts. Here, we report the use of hyperpolarized 13C NMR spectroscopy to detect sudden changes in cardiac metabolism in isolated, perfused rat hearts in response to adrenergic stimulation. METHODS:Met...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25419
更新日期:2015-08-01 00:00:00
abstract::To obtain a better understanding of the mechanisms underlying early changes in the brain water apparent diffusion coefficient (ADC) observed in cerebral ischemia, dynamic changes in the ADC of water and in the energy status were measured at postnatal day 8 or 9 in neonatal rat brains after cardiac arrest using 1H MRS/...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910360110
更新日期:1996-07-01 00:00:00
abstract::The use of phase correlation to detect rigid-body translational motion is reviewed and applied to individual echotrains in turbo-spin-echo data acquisition. It is shown that when the same echotrain is acquired twice, the subsampled correlation provides an array of delta-functions, from which the motion that occurred b...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21883
更新日期:2009-03-01 00:00:00
abstract::A stereotaxic restraining assembly was designed and developed for simultaneous electrophysiological recordings and functional MRI (fMRI) data acquisition from a conscious rat. The design of the nonmagnetic stereotaxic apparatus facilitated the restraining of head and body of the unanesthetized conscious animal during ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.10441
更新日期:2003-05-01 00:00:00
abstract::A demonstration of MR guided thermal surgery involved experiments with imaging of focused ultrasound in an MRI system, measurements of the thermal transients and a thermal analysis of the resulting images. Both the heat distribution and the creation of focused ultrasound lesions in gel phantoms, in vitro bovine muscle...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910300115
更新日期:1993-07-01 00:00:00
abstract::The differential effects of high temperature on 9L rat gliosarcoma cells cultured in two distinctive forms, namely, anchored monolayer cells and multicellular spheroids, were investigated using 31P nuclear magnetic resonance spectroscopy. The critical temperatures resulting in irreversible changes in cellular energeti...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910190233
更新日期:1991-06-01 00:00:00
abstract::The incorporation of RF coils into the tips of intravascular devices has been shown to enable the localization of catheters and guidewires under MR guidance. Furthermore, such coils can be used for endoluminal imaging. The long cable required to connect the coil with the scanner input inadvertently acts as a dipole an...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1522-2594(200004)43:4<615::aid-mrm19
更新日期:2000-04-01 00:00:00
abstract::The pulse wave velocity (PWV) of aortic blood flow is considered a surrogate for aortic compliance. A new method using phase-contrast (PC)-MRI is presented whereby the spatial and temporal profiles of axial velocity along the descending aorta can be analyzed. Seventeen young healthy volunteers (the YH group), six olde...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21034
更新日期:2006-10-01 00:00:00
abstract::Three-dimensional (3D) coronary imaging has the potential to overcome problems resulting from vessel tortuosity and to reduce partial volume effects. With these techniques, however, acquisition times are long and respiratory motion artifacts problematical. This work describes the development of a method that applies p...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1522-2594(199903)41:3<555::aid-mrm19
更新日期:1999-03-01 00:00:00
abstract::Regional values of fractional anisotropy (FA) and mean diffusivity (D(av)) of in vivo and excised rat spinal cords were measured using an iscosahedral encoding scheme that is based on 21 uniformly distributed and alternating gradient directions with an echo planar imaging (EPI) readout. Based on the water phantom stud...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.20304
更新日期:2005-01-01 00:00:00
abstract:PURPOSE:Application of phase rotation to the STRESS (=STEAM+PRESS) localization scheme, to shorten echo time, minimize J-coupling dephasing and estimate B1+ inhomogeneity. STRESS (=STEAM + PRESS) simultaneously refocuses and acquires the double spin echo (SE123 ) and stimulated echo (STE- ) pathways, combining PRESS-li...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26911
更新日期:2018-05-01 00:00:00