Abstract:
:Both post-contrast myocardial T1 and extracellular volume (ECV) have been reported to be associated with diffuse interstitial fibrosis. Recently, the cardiovascular magnetic resonance (CMR) field is recognizing that post-contrast myocardial T1 is sensitive to several confounders and migrating towards ECV as a measure of collagen volume fraction. Several recent studies using widely available Modified Look-Locker Inversion-recovery (MOLLI) have reported ECV cutoff values to distinguish between normal and diseased myocardium. It is unclear if these cutoff values are translatable to different T1 mapping pulse sequences such as arrhythmia-insensitive-rapid (AIR) cardiac T1 mapping, which was recently developed to rapidly image patients with cardiac rhythm disorders. We sought to evaluate, in well-controlled canine and pig experiments, the relative accuracy and precision, as well as intra- and inter-observer variability in data analysis, of ECV measured with AIR as compared with MOLLI. In 16 dogs, as expected, the mean T1 was significantly different (p < 0.001) between MOLLI (891 ± 373 ms) and AIR (1071 ± 503 ms), but, surprisingly, the mean ECV between MOLLI (21.8 ± 2.1%) and AIR (19.6 ± 2.4%) was also significantly different (p < 0.001). Both intra- and inter-observer agreements in T1 calculations were higher for MOLLI than AIR, but intra- and inter-observer agreements in ECV calculations were similar between MOLLI and AIR. In six pigs, the coefficient of repeatability (CR), as defined by the Bland-Altman analysis, in T1 calculation was considerably lower for MOLLI (32.5 ms) than AIR (82.3 ms), and the CR in ECV calculation was also lower for MOLLI (1.8%) than AIR (4.5%). In conclusion, this study shows that MOLLI and AIR yield significantly different T1 and ECV values in large animals and that MOLLI yields higher precision than AIR. Findings from this study suggest that CMR researchers must consider the specific pulse sequence when translating published ECV cutoff values into their own studies.
journal_name
NMR Biomedjournal_title
NMR in biomedicineauthors
Hong K,Kim Ddoi
10.1002/nbm.3221subject
Has Abstractpub_date
2014-11-01 00:00:00pages
1419-26issue
11eissn
0952-3480issn
1099-1492journal_volume
27pub_type
杂志文章abstract::Patients with different types of mucopolysaccharidoses (MPS) lack specific lysosomal enzymes, which leads to tissue accumulation and urinary excretion of glycosaminoglycans (GAGs). Since little is known about the molecular composition of the excreted GAG fragments, we used two-dimensional [1H,13C]-correlation nuclear ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.833
更新日期:2003-06-01 00:00:00
abstract::Glucosamine (GlcN) modulates fluoropyrimidine metabolism and enhances cytotoxicity of 5-fluorouridine (FUrd), but not of 5-fluorouracil (FUra), in human tumor models. To elucidate the underlying metabolic differences between FUra and FUrd, by the use of 19F and 31P NMR spectroscopy we studied these drugs in multicell ...
journal_title:NMR in biomedicine
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doi:10.1002/(sici)1099-1492(199905)12:3<157::aid-nbm55
更新日期:1999-05-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.675
更新日期:2000-12-01 00:00:00
abstract::Hyperpolarised (HP) (13)C NMR allows enzymatic activity to be probed in real time in live biological systems. The use of in vitro models gives excellent control of the cellular environment, crucial in the understanding of enzyme kinetics. The increased conversion of pyruvate to lactate in cancer cells has been well st...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3341
更新日期:2015-08-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
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更新日期:2017-04-01 00:00:00
abstract::Magnetic resonance imaging (MRI) in pregnancy is commonly undertaken in the left lateral tilt (LLT) position to prevent inferior vena cava (IVC) compression and supine hypotensive events, although this may be suboptimal for image quality. The supine position may also have an adverse effect on fetal well-being. The spi...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4475
更新日期:2021-01-21 00:00:00
abstract::We have developed a reliable, reproducible model of hypoxia in the gerbil. 1H and 31P NMR spectroscopy demonstrates that cerebral energy metabolism is very resistant to hypoxia. Cerebral blood flow (measured by hydrogen clearance) began to increase when the arterial oxygen tension (paO2) was reduced to 40-50 mm Hg, an...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940050109
更新日期:1992-01-01 00:00:00
abstract::The physiological status of anesthetized rats greatly influences blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI). Monitoring of physiological parameters, particularly partial pressure of carbon dioxide (pCO(2)) levels in the blood, is therefore an important part in the design and ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.978
更新日期:2005-11-01 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
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3962
更新日期:2019-10-01 00:00:00
abstract::It is generally accepted that tumour microcirculation, blood flow, oxygen and nutrient supply, tissue pH distribution, and the bioenergetic status--factors which are usually closely linked and which define the so-called metabolic microenvironment--can markedly influence the therapeutic response of malignant tumours to...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.1940050505
更新日期:1992-09-01 00:00:00
abstract:PURPOSE:To investigate the feasibility of using multiple flip angles in dynamic contrast enhanced (DCE) MRI to reduce the uncertainty in estimation of intracellular water lifetime (τi ). METHODS:Numerical simulation studies were conducted to assess the uncertainty in estimation of τi using dynamic contrast enhanced MR...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4135
更新日期:2019-11-01 00:00:00
abstract::The sodium-calcium exchanger (NCX) is one of the transporters contributing to the control of intracellular calcium (Ca(2+)) concentration by normally mediating net Ca(2+) efflux. However, the reverse mode of the NCX can cause intracellular Ca(2+) concentration overload, which exacerbates the myocardial tissue injury r...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1414
更新日期:2009-10-01 00:00:00
abstract::Acute kidney injury (AKI) in mice caused by sustained ischemia followed by reperfusion is associated with acute tubular necrosis and renal dysfunctional blood flow. Although the principal role of the kidney is the maintenance of acid-base balance, current imaging approaches are unable to assess this important paramete...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3720
更新日期:2017-07-01 00:00:00
abstract::We describe and discuss the application of three-dimensional (3D) time-of-flight (TOF) magnetic resonance angiography (MRA) to visualize non-invasively the cerebral vasculature of the rat. MR angiograms of healthy spontaneously hypertensive rats were obtained without the use of contrast agents. Total imaging time rang...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/(sici)1099-1492(199906)12:4<189::aid-nbm55
更新日期:1999-06-01 00:00:00
abstract::Development and evaluation of new anticancer drugs are expedited when minimally invasive biomarkers of pharmacokinetic and pharmacodynamic behaviour are available. Gene-directed enzyme prodrug therapy (GDEPT) is a suicide gene therapy in which the anticancer drug is activated in the tumor by an exogenous enzyme previo...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1375
更新日期:2009-06-01 00:00:00
abstract::Chronic pain is a major problem for the individual and for society. Despite a range of drugs being available to treat chronic pain, only inadequate pain relief can be achieved for many patients. There is therefore a need for the development of new analgesic compounds. The assessment of pain depends to date entirely on...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1076
更新日期:2006-10-01 00:00:00
abstract::There has been growing interest in understanding energy metabolism in human embryos generated using assisted reproductive techniques (ART) for improving the overall success rate of the method. Using NMR spectroscopy as a noninvasive tool, we studied human embryo metabolism to identify specific biomarkers to assess the...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2814
更新日期:2013-01-01 00:00:00
abstract::In this methodological paper I report the stereotactic correlation of different magnetic resonance imaging (MRI) techniques [MR angiography (MRA), MRI, blood bolus tagging (STAR), functional MRI, and high-resolution BOLD venography (HRBV)] in patients with cerebral arterio-venous malformations (AVM) and brain tumors. ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.714
更新日期:2001-11-01 00:00:00
abstract::Aminoacylase 1 deficiency is a novel inborn error of metabolism. The clinical significance of the deficiency is under discussion, as well as the possible consequences of the defect for brain metabolism and function. This study includes the five originally published cases as well as three novel ones. NMR spectroscopy o...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1170
更新日期:2008-02-01 00:00:00
abstract::This study investigated the association between the total choline (tCho) concentration and the clinical characteristics and biomarker status of breast cancer. Sixty-two patients with breast cancer, 1.5 cm or larger in size on MR images, were studied. The tCho concentration was correlated with the MRI features, contra...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1595
更新日期:2011-04-01 00:00:00
abstract::Quantitative mapping of MR tissue parameters such as the spin-lattice relaxation time (T1 ), the spin-spin relaxation time (T2 ), and the spin-lattice relaxation in the rotating frame (T1ρ ), referred to as MR relaxometry in general, has demonstrated improved assessment in a wide range of clinical applications. Compar...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4416
更新日期:2020-10-15 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1529
更新日期:2010-11-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3307
更新日期:2015-06-01 00:00:00
abstract::The goal of this study was to validate metabolite quantification at short TE, with particular focus on how to best account for the macromolecular signal contribution. A robust, short-TE PRESS protocol is presented, which allows reliable quantification, in vivo, of metabolite signals at 3 T in human brain. Water suppre...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1219
更新日期:2008-06-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4284
更新日期:2020-05-01 00:00:00
abstract::The transverse relaxation rates R2 and R2* were measured at 3 T in the substantia nigra of the midbrain of adult normal human controls. The relaxation rate arising from magnetic inhomogeneities, R2', was calculated from the relationship R2* = R2 + R2'. No significant differences were found for any parameters between l...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940080106
更新日期:1995-02-01 00:00:00
abstract::Glucose metabolism in control and estrogen stimulated rat uteri was investigated using 13C NMR spectroscopy. By employing an NMR adapted perifusion system, and developing protocols and methods based on the application of [1-13C]glucose labeling, it was possible to measure, with a temporal resolution of 10 min, the kin...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940070503
更新日期:1994-08-01 00:00:00
abstract::Previous studies have demonstrated that using hyperpolarized [2-13 C]pyruvate as a contrast agent can reveal 13 C signals from metabolites associated with the tricarboxylic acid (TCA) cycle. However, the metabolites detectable from TCA cycle-mediated oxidation of [2-13 C]pyruvate are the result of several metabolic st...
journal_title:NMR in biomedicine
pub_type: 杂志文章
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更新日期:2018-01-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1376
更新日期:2009-07-01 00:00:00