Abstract:
:In this work we introduce the concept of correlation chemical shift imaging (CCSI). Novel CCSI pulse sequences are demonstrated on clinical scanners for two-dimensional Correlation Spectroscopy (COSY) and Total Correlation Spectroscopy (TOCSY) imaging experiments. To date there has been limited progress reported towards a feasible and robust multivoxel 2D COSY. Localized 2D TOCSY imaging is shown for the first time in this work. Excitation with adiabatic GOIA-W(16,4) pulses (Gradient Offset Independent Adiabaticity Wurst modulation) provides minimal chemical shift displacement error, reduced lipid contamination from subcutaneous fat, uniform optimal flip angles, and efficient mixing for coupled spins, while enabling short repetition times due to low power requirements. Constant-density spiral readout trajectories are used to acquire simultaneously two spatial dimensions and f(2) frequency dimension in (k(x),k(y),t(2)) space in order to speed up data collection, while f(1) frequency dimension is encoded by consecutive time increments of t(1) in (k(x),k(y),t(1),t(2)) space. The efficient spiral sampling of the k-space enables the acquisition of a single-slice 2D COSY dataset with an 8 × 8 matrix in 8:32 min on 3 T clinical scanners, which makes it feasible for in vivo studies on human subjects. Here we present the first results obtained on phantoms, human volunteers and patients with brain tumors. The patient data obtained by us represent the first clinical demonstration of a feasible and robust multivoxel 2D COSY. Compared to the 2D J-resolved method, 2D COSY and TOCSY provide increased spectral dispersion which scales up with increasing main magnetic field strength and may have improved ability to unambiguously identify overlapping metabolites. It is expected that the new developments presented in this work will facilitate in vivo application of 2D chemical shift correlation MRS in basic science and clinical studies.
journal_name
NMR Biomedjournal_title
NMR in biomedicineauthors
Andronesi OC,Gagoski BA,Adalsteinsson E,Sorensen AGdoi
10.1002/nbm.1730subject
Has Abstractpub_date
2012-02-01 00:00:00pages
195-209issue
2eissn
0952-3480issn
1099-1492journal_volume
25pub_type
杂志文章abstract::Mouse models are increasingly used to study the pathophysiology of myocardial infarction in vivo. In this area, MRI has become the gold standard imaging modality, because it combines high spatial and temporal resolution functional imaging with a large variety of methods to generate soft tissue contrast. In addition, (...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.2767
更新日期:2012-08-01 00:00:00
abstract::Cerebral ischemia provokes tissue damage by two major patho-physiological mechanisms. Direct cell necrosis is induced by diminished access of neurons and glia to essential nutrients such as glucose and oxygen leading to energy failure. A second factor of cellular loss is related to the activation of immune-competent c...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.770
更新日期:2002-06-01 00:00:00
abstract::Signal of lung parenchymal tissue from the living rat and mouse lung was detected at 4.7 T with a good signal-to-noise ratio and motion-suppressed artifacts using a short TE gradient-echo sequence. Neither cardiac nor respiratory gating were applied, and animals respired freely during data collection. Mean T(2)* relax...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.706
更新日期:2001-08-01 00:00:00
abstract::Transcranial direct current stimulation (tDCS) is used in numerous clinical studies and considered an effective and versatile add-on therapy in neurorehabilitation. To date, however, the underlying neurobiological mechanisms remain elusive. In a rat model of tDCS, we recently observed a polarity-dependent accumulation...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3244
更新日期:2015-02-01 00:00:00
abstract::Lung cancer is a primary cause of cancer deaths worldwide. Timely detection of this pathology is necessary to delay or interrupt lung cancer progression, ultimately resulting in a possible better prognosis for the patient. In this context, magnetic resonance imaging (MRI) is especially promising. Ultra-short echo time...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3790
更新日期:2017-11-01 00:00:00
abstract::In this study the conjugated macromolecular ligand, diethylenetriaminepentaacetic acid (DTPA)-amide-dextran, was synthesized by attaching DTPA to the dextran macromolecule (M(r) approximately 6000) by a covalent amide bond. Subsequently, DTPA-amide-dextran was complexed with either of the two lanthanide metal ions dys...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940080404
更新日期:1995-06-01 00:00:00
abstract::Modified gradient-echo MR techniques were applied to study the effects of inflow on functional brain imaging studies using visual and motor cortex stimulation. The results demonstrate that the large signal changes, seen in previously reported gradient-echo studies at 1.5-2.0 T, are dominated by direct inflow effects, ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940070113
更新日期:1994-03-01 00:00:00
abstract::1H NMR spin-echo spectroscopy has been used to study the metabolism of exogenous compounds in human erythrocytes. The non-invasive nature of the technique and the continuous monitoring makes it ideal to investigate both the conversion of substrates and the occurrence and the nature of the products. Hydrolysis rates ma...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940030603
更新日期:1990-12-01 00:00:00
abstract::Reconstruction of MRI data is based on exact knowledge of all magnetic field dynamics, since the interplay of RF and gradient pulses generates the signal, defines the contrast and forms the basis of resolution in spatial and spectral dimensions. Deviations caused by various sources, such as system imperfections, delay...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3359
更新日期:2016-09-01 00:00:00
abstract::Results of the evaluation of transrectal ultrasound (TRUS) guided needle biopsy of voxels identified as suspicious of malignancy on magnetic resonance spectroscopic imaging (MRSI) in a large cohort of men (n = 83) with abnormal digital rectal examination (DRE) [prostate specific antigen (PSA) 0-4 ng/ml] or PSA less th...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1083
更新日期:2007-02-01 00:00:00
abstract::In this study, the upper-limit volume (gas plus partial tissue volume) as well as absolute volume (gas only) of lungs measured with hyperpolarized (3)He-MR imaging is compared with that determined by micro-computed tomography (CT) under similar ventilation conditions in normal rats. Five Brown Norway rats (210-259 g) ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1470
更新日期:2010-05-01 00:00:00
abstract::Prader-Willi syndrome (PWS) is a genetic imprinting disorder characterized mainly by hyperphagia and early childhood obesity. Previous functional neuroimaging studies used visual stimuli to examine abnormal activities in the eating-related neural circuitry of patients with PWS. It was found that patients with PWS exhi...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2900
更新日期:2013-06-01 00:00:00
abstract::The aim of this study was to investigate physiological variations of the water T2 relaxation time in vertebral bone marrow with respect to age, body mass index (BMI), sex and proton density fat fraction (PDFF) based on single-voxel magnetic resonance spectroscopy (MRS) at 3 T. Multi-TE single-voxel STEAM MRS data of a...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4439
更新日期:2020-11-17 00:00:00
abstract::To assess infarction development in pig hearts, Mn-enhanced and Gd-enhanced MRI were used. In domestic pigs (25-35 kg, n = 37), the first and second diagonal branches of the left anterior descending coronary artery were ligated to induce acute ischemia and infarction (ischemia+reperfusion) or chronic infarction of inc...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1297
更新日期:2009-02-01 00:00:00
abstract::We describe the optimal high-level postprocessing of single-voxel (1)H magnetic resonance spectra and assess the benefits and limitations of automated methods as diagnostic aids in the detection of recurrent brain tumor. In a previous clinical study, 90 long-echo-time single-voxel spectra were obtained from 52 patient...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1041
更新日期:2006-08-01 00:00:00
abstract::The use of cerebral water as an internal intensity standard for the quantitation of spatially localized proton spectra of the human brain is investigated. The method is validated on standard samples of N-acetyl aspartate (NAA) and lactate, and possible sources of error are discussed. Using the STEAM pulse sequence, co...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940060114
更新日期:1993-01-01 00:00:00
abstract::Phosphatidylcholine (PC) metabolism in bovine adrenal chromaffin cells has been studied in vivo with 100 MHz 13C NMR spectroscopy. The incorporation of 13[CH3]choline was examined in cells embedded in 1% agarose strands and perfused at 37 degrees C. The pattern of 13C NMR spectroscopy. The incorporation of [13CH3]chol...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940040304
更新日期:1991-06-01 00:00:00
abstract::A review of the theory, technology, and use of radio frequency (RF) coils for small-animal MRI is presented. It includes a brief overview of MR signal-to-noise (S/N) analysis and discussions of the various coils commonly used in small-animal MR: surface coils, linear volume coils, birdcages, and their derivatives. The...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1149
更新日期:2007-05-01 00:00:00
abstract::Renal urea handling is central to the urine concentrating mechanism, and as such the ability to image urea transport in the kidney is an important potential imaging biomarker for renal functional assessment. Glucagon levels associated with changes in dietary protein intake have been shown to influence renal urea handl...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4028
更新日期:2019-01-01 00:00:00
abstract::Quantification of metabolites is a goal of many biomedical NMR studies. To obtain absolute measurements of metabolite concentrations is often both difficult and time-consuming. In this paper a method for determining metabolite concentrations directly is described and validated. It is applicable to studies of amphibian...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940050306
更新日期:1992-05-01 00:00:00
abstract::The purpose of this work was to harmonize data acquisition and post-processing of single voxel proton MRS ((1) H-MRS) at 7 T, and to determine metabolite concentrations and the accuracy and reproducibility of metabolite levels in the adult human brain. This study was performed in compliance with local institutional hu...
journal_title:NMR in biomedicine
pub_type: 杂志文章,多中心研究
doi:10.1002/nbm.3252
更新日期:2015-03-01 00:00:00
abstract::An evaluation of the reproducibility and accuracy of the NMR human blood test for cancer described by Fossel, E. T., Carr, J. M. and McDonagh, J., (New England Journal of Medicine 315, 1369-1376) in 1986 has been conducted jointly at the National Cancer Institute-Frederick Cancer Research Facility, Frederick, MD (NCI-...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.1940010307
更新日期:1988-06-01 00:00:00
abstract::The steady-state distribution of the general anesthetic halothane in different rat tissues, including a renal adenocarcinoma with and without hyperthermia treatment, has been evaluated by in vivo 19F NMR spectroscopy. The 19F spectra of halothane (which is a hydrophobic probe) from within tissue show differences in th...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940060502
更新日期:1993-09-01 00:00:00
abstract::13C MRS was installed on a clinical scanner at 1.5 T in order to facilitate integrated MR examinations of human brain disorders. Using a simplified protocol, (1-(13)C) glucose and/or (1-(13)C) acetate were administered orally or by intravenous infusion. (13)C spectra of diagnostic quality were acquired in more than 10...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.852
更新日期:2003-10-01 00:00:00
abstract::Elevated brain myo-inositol (m-Ins) concentration (a putative marker of neuroinflammation) has been reported in patients suffering from type 2 diabetes mellitus (T2DM). Obesity alone and T2DM have been found to be associated with a lower concentration of N-acetyloaspartate and N-acetylaspartylglutamate (tNAA, a marker...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3957
更新日期:2018-09-01 00:00:00
abstract:OBJECTIVES:Quantitative MRI (qMRI) of muscles is a promising tool to measure disease progression or to assess therapeutic effects in neuromuscular diseases. Longitudinal imaging studies are needed to show sensitivity of qMRI in detecting disease progression in spinal muscular atrophy (SMA). In this pilot study we there...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4473
更新日期:2021-01-22 00:00:00
abstract::In imaging of human lungs with hyperpolarised noble gases, measurements of apparent diffusion coefficient (ADC) and relaxation time provide valuable information for the assessment of lung microstructure. In this work, a sequence was developed for interleaved acquisition of ventilation images, ADC, T(2)* and flip angle...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1710
更新日期:2012-01-01 00:00:00
abstract::Dynamic contrast-enhanced MRI (DCE MRI) has been used to study tumor response to treatment for many years. In this study, the modified full width at half-maximum (mFWHM), calculated from the wash-in slope histogram, is proposed as a parameter for the evaluation of changes in tumor heterogeneity which respond to radiot...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2882
更新日期:2013-04-01 00:00:00
abstract::The accuracy and precision of the quantification of metabolite concentrations in in vivo (1) H NMR spectroscopy are affected by linewidth and signal-to-noise ratio (SNR). To study the effect of both factors in in vivo (1) H NMR spectra acquired at ultrahigh field, a reference spectrum was generated by summing nine in ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2821
更新日期:2013-01-01 00:00:00
abstract::Vessel size index (VSI), a parameter related to the distribution of vessel diameters, may be estimated using two MRI approaches: (i) dynamic susceptibility contrast (DSC) MRI following the injection of a bolus of Gd-chelate. This technique is routinely applied in the clinic to assess intracranial tissue perfusion in p...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1734
更新日期:2012-02-01 00:00:00