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Zhou Jinyuan - - 2003
In the past decade, it has become possible to use the nuclear (proton, 1H) signal of the hydrogen atoms in water for noninvasive assessment of functional and physiological parameters with magnetic resonance imaging (MRI). Here we show that it is possible to produce pH-sensitive MRI contrast by exploiting the exchange ...
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Terpstra Melissa - - 2003
The concentration of reduced glutathione (GSH), an antioxidant, may be altered in various brain diseases. MEGA-PRESS was used to edit for the (1)H NMR signal from GSH in the occipital lobe of 12 normal humans. In all studies, GSH was clearly detected with a spectral pattern consistent with spectra acquired ...
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Takeuchi Mayumi - - 2003
Magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (proton MRS) findings before and after carnitine therapy in a patient with methylmalonic acidemia (MMA) are evaluated. The hyperintensity on T2-weighted image and diffusion-weighted image and the decreased apparent diffusion coefficient of bilateral basal ganglia were normalized in parallel with normalization ...
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Tugnoli Vitaliano - - 2003
In vivo and in vitro Magnetic Resonance Spectroscopy is useful for monitoring changes in intracellular metabolites of human cerebral and renal tissues. Healthy and tumoral tissues of different histologic types have been characterized from a biochemical point of view. In vitro molecular characterization is performed on both the aqueous and ...
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Martin David D - - 2003
To our knowledge, this is the first report of hypogonadotropic hypogonadism, or growth hormone deficiency, in a patient without non-Pallister-Hall syndrome who had hypothalamic hamartoma diagnosed on the basis of MR imaging and MR spectroscopy findings. On short-TE proton MR spectra, the N-acetylaspartate concentration in the hamartoma was lower than ...
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Takeuchi Mayumi - - 2003
This is a report on a case of carbohydrate-deficient glycoprotein syndrome (CDGS) with neurological deficits. Magnetic resonance (MR) images showed remarkable atrophy of the cerebellum and brainstem, and hypointensity was seen in the pallidum on diffusion-weighted images (DWI), suggesting deposits of metal substances. In the cerebellum, proton MR spectroscopy (MRS) ...
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Srinivas M - - 2003
Magnetic resonance (MR) imaging is a useful tool to study the anatomy of the testis while 31P magnetic resonance spectroscopy (MRS) provides a non-invasive alternative method to demonstrate the metabolic status of testes. This study was designed to test whether the protective role of cyclosporine in experimental unilateral blunt testicular ...
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Wenserski Frank - - 2003
PURPOSE: To investigate whether advanced magnetic resonance (MR) imaging techniques such as diffusion-weighted (DW) and perfusion-weighted (PW) MR imaging and hydrogen 1 (1H) MR spectroscopy can depict functional and pathophysiologic mechanisms in patients who have minor motor deficits (MMDs) associated with human immunodeficiency virus 1 (HIV-1). MATERIALS AND METHODS: Thirty-two ...
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Jan Wajanat - - 2003
Maple syrup urine disease (MSUD) is an inborn error of amino acid metabolism, which affects the brain tissue resulting in impairment or death if untreated. Imaging studies have shown reversible brain edema during acute metabolic decompensation. The purpose of this paper is to describe the diffusion-weighted imaging (DWI) and spectroscopy ...
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Kubo Hitoshi - - 2003
OBJECTIVE: The purpose of this study was to evaluate the reproducibility of in vivo quantitative proton MR spectroscopy (MRS) by repeated-measure analysis of variance and intraclass correlation coefficient (ICC) including assessment of both inter- and intrasubject variation. METHODS: The concentration of metabolites was quantified using long-TR and short-TE stimulated-echo acquisition ...
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Kawamitsu Hideaki - - 2003
The quantification of intrahepatic lipids (IHLs) has attracted a great deal of interest pertaining to diagnostic treatment of type 2 diabetes mellitus. We report on an innovative approach to visualizing IHLs quantitatively by creating the best mix of the advantages of proton magnetic resonance spectroscopy (MRS) and the gradient echo ...
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Brauer Manfred - - 2003
The biochemical and physiological processes involved in apoptosis were described from the perspective of detection by standard, clinical, noninvasive imaging modalities. The difficulties of monitoring apoptosis in vivo were discussed. Magnetic resonance imaging (MRI) approaches used to study apoptosis were surveyed. The cell shrinkage associated with apoptosis can be detected ...
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Gulati Sheffali - - 2003
In the last three decades a range of non-invasive biophysical techniques have been developed, of which Magnetic Resonance (MR) has proved to be the most versatile. Its non-invasive and safe nature has made it the most important diagnostic and research tool in clinical medicine. MR Spectroscopy (MRS) is the only ...
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Möller H E - - 2003
In vivo phosphorus magnetic resonance spectroscopy (MRS) was used to investigate markers of the cerebral energy status in two patients with glutaric aciduria type I (GA-I). Besides an increased concentration of phosphomonoesters in one patient, no other significant alterations from controls were found. This might indicate increased resynthesis of dendritic ...
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Cho Yong Pil - - 2003
Localized in vivo proton magnetic resonance spectroscopy ((1)H-MRS) has been used to measure the metabolic status of the human brain in a non-invasive manner; thus, it is often called "a non-invasive biochemical assay". MRS is more sensitive than magnetic resonance imaging (MRI) in detecting ischemic damage by measuring the metabolic ...
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Braun Kees P J - - 2003
PURPOSE: To evaluate cerebral metabolism in clinical hydrocephalus with (1)H magnetic resonance spectroscopy (MRS). MATERIALS AND METHODS: In 24 children and adults with progressive, arrested, or normal pressure hydrocephalus, long-echo time (1)H MR spectra were acquired from periventricular white matter and intraventricular cerebrospinal fluid (CSF). Metabolite ratios, and the presence ...
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deGrauw Ton J - - 2003
To describe the clinical, spectroscopic and neuropsychological features of the first family diagnosed with a defect in the creatine transporter. Proton Magnetic Resonance Spectroscopy (MRS) indicated an absence of creatine and phosphocreatine in the brain of a male patient characterized by developmental delay, mild epilepsy and severe expressive language impairment. ...
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Lei Hao - - 2003
In vivo (31)P spectra were acquired from the human primary visual cortex at 7 T. The relaxation times of the cerebral metabolites, intracellular pH, rate constant (k(f)) of the creatine kinase (CK) reaction, and nuclear Overhauser enhancement (NOE) on the detected phosphorus moieties from irradiation of the water spins were ...
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Gambini Anna - - 2003
A case of Marchiafava-Bignami disease was serially evaluated with MR imaging and MR spectroscopy at 1, 2, 4, and 11 months after the onset of symptoms. The first MR imaging study showed extensive abnormal signal intensity of the corpus callosum without macroscopic changes; a diagnosis of Marchiafava-Bignami disease was made, ...
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Mateescu Gheorghe D - - 2003
Functional oxygen-17 magnetic resonance (MR) imaging and localized spectroscopy is defined as the ensemble of MR measurements aiming at in vivo, noninvasive characterization of oxygen transport and utilization. After a brief description of the present status of in vivo 17O-MR, preliminary results are reported on oxygen delivery and consumption in ...
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Peterson P L - - 2003
Neuropsychiatric symptoms are common in systemic lupus erythematosus (SLE) but are poorly understood. Although there is a wide spectrum of clinical manifestations, brain histology often simply shows a bland vasculopathy. Magnetic resonance techniques such as magnetic resonance spectroscopy, magnetization transfer imaging and diffusion weighted imaging have been used to try ...
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Sheppard Norman - - 2003
Raymond Andrew's career in nuclear magnetic resonance (NMR) began two years after the independent discoveries of the phenomenon by Edward Purcell of Harvard University (Purcell et al. 1946) and by Felix Bloch of Stanford University (Bloch et al. 1946) for which they shared the Nobel Prize for Physics in 1952. ...
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Pietz J - - 2003
Transport of phenylalanine (Phe) and the other large neutral amino acids across the blood-brain barrier plays a crucial role in the pathogenesis of phenylketonuria (PKU). Thus, investigation of Phe transport kinetics by means of proton magnetic resonance spectroscopy (1H MRS) became an important research area in the mid 1990s. As ...
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Golman K - - 2003
MRI provides unsurpassed soft tissue contrast, but the inherent low sensitivity of this modality has limited the clinical use to imaging of water protons. With hyperpolarization techniques, the signal from a given number of nuclear spins can be raised more than 100 000 times. The strong signal enhancement enables imaging ...
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Seeger Uwe - - 2003
Short echo time (TE) proton MR spectra of the brain include signals of several metabolites as well as macromolecules. In various pathologies, such as brain tumors and multiple sclerosis (MS), the presence of mobile lipids or pathologically altered macromolecules may provide useful additional diagnostic information. A reliable quantitation of these ...
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Mason Graeme F - - 2003
Magnetic resonance spectroscopy (MRS) of hydrogen and carbon allow the study of neurochemical alterations in neuropsychiatric disorders. This paper discusses the basic theory of MRS in order to provide an understanding of this complicated technical area. A variety of applications of hydrogen MRS in the study of neuropsychiatric disorders are ...
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Lin Doris D M - - 2003
PURPOSE AND BACKGROUND: Mitochondrial diseases are a group of inherited disorders caused by a derangement of mitochondrial respiration. The clinical manifestations are heterogeneous, and the diagnosis is often based on information acquired from multiple levels of inquiry. MR spectroscopy has previously been shown to help detect an abnormal accumulation of ...
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Goo Hyun Woo - - 2003
In this report, we describe the findings of diffusion MR imaging and proton MR spectroscopy in two infants with acute necrotizing encephalopathy in which there was characteristic symmetrical involvement of the thalami. Diffusion MR images of the lesions showed that the observed apparent diffusion coefficient (ADC) decrease was more prominent ...
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Silverstone Peter H - - 2002
AIMS: To help determine the effects of dextro-amphetamine on the phosphoinositol cycle (PI-cycle) in humans, (1)H and (31)P magnetic resonance spectroscopy (MRS) was utilized in 17 healthy volunteers. This was an open-label study carried out before and after administration of 20 mg oral dextro-amphetamine. Subjects also rated the subjective effects ...
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Binesh Nader - - 2002
The test-retest reliability of two-dimensional (2D) correlated spectroscopy (COSY) was studied on a whole-body 1.5T MRI scanner. Single-voxel localized 2D proton spectra were recorded in vitro as well as in vivo using a recently implemented localized chemical shift correlated spectroscopic (L-COSY) sequence. A total of 40 in vitro and 40 ...
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Cecil Kim M - - 2002
We present a report of MRI and proton MR spectroscopy (MRS) findings in an adolescent patient with Down syndrome and Crohn disease treated with metronidazole. MRI revealed signal abnormalities within the corpus callosum, basal ganglia, and brainstem. Proton MRS examination demonstrated a persistent lactate elevation during metronidazole treatment. Clinical, spectroscopic, ...
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Griffiths J R - - 2002
This review describes problems and solutions encountered in large scale multicentre trials of Magnetic Resonance Methods for monitoring cancer. It is illustrated with reference to the Multi-Institutional Group on Magnetic Resonance Spectroscopy (MRS) Applications to Cancer which was set up to perform a trial of 31P MRS for monitoring non-invasively ...
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Ith Michael - - 2002
Postmortem decomposition of brain tissue was investigated by (1)H-magnetic resonance spectroscopy (MRS) in a sheep head model and selected human cases. Aiming at the eventual estimation of postmortem intervals in forensic medicine, this study focuses on the characterization and identification of newly observed metabolites. In situ single-voxel (1)H-MRS at 1.5 ...
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Kato Zenichiro - - 2002
Subacute sclerosing panencephalitis is an encephalopathy caused by a persistent measles virus infection. We examined a 13-year-old girl with subacute sclerosing panencephalitis and performed a magnetic resonance spectroscopic study to evaluate the in vivo pathophysiologic abnormality. The results suggested the occurrence of inflammatory processes and glial proliferation prior to neuronal ...
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Shen Jun - - 2002
In vivo magnetic resonance spectroscopy (MRS) is a noninvasive technique for the measurement of the concentration and synthesis of metabolites in the brain. Application of the state-of-the-art in vivo (13)C and (15)N MRS techniques to studying the synthesis of glutamate and glutamine has revealed that the glutamate-glutamine cycle between neurons ...
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Chan Y L - - 2002
We herein describe the case of a patient with chronic renal failure complicated by star fruit poisoning. T2-weighted and diffusion-weighted MR imaging showed hyperintense lesions at the thalami and right temporo-occipital cortex. Single voxel proton MR spectroscopy revealed elevation of lactate and (31)phosphorous MR spectroscopy revealed elevation of inorganic phosphate ...
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Flemming Katharina - - 2002
Alpers-Huttenlocher syndrome, considered a mitochondrial disease, combines encephalopathy and liver failure. An 11-year-old boy with Alpers-Huttenlocher syndrome underwent conventional MR imaging, diffusion-weighted imaging, and proton MR spectroscopy. Diffusion-weighted imaging showed cytotoxic edema interpreted as acute-phase encephalopathy. MR spectroscopy revealed a lactate peak in the cortex that appeared abnormal on diffusion-weighted ...
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Mascalchi Mario - - 2002
A patient with suprasellar and brain stem involvement in Erdheim Chester disease (ECD) underwent magnetic resonance (MR) imaging and proton MR spectroscopy (1H MRS) of the ventral pons before and 1, 4 and 18 months after external whole-brain (24 Gy) radiotherapy. By revealing a decrease of the N-acetyl-aspartate/choline ratio in ...
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Drost Dick J - - 2002
AAPM Magnetic Resonance Task Group #9 on proton magnetic resonance spectroscopy (MRS) in the brain was formed to provide a reference document for acquiring and processing proton (1H) MRS acquired from brain tissue. MRS is becoming a common adjunct to magnetic resonance imaging (MRI), especially for the differential diagnosis of ...
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Methylsulfonylmethane observed by in vivo proton magnetic resonance spectroscopy in a 5-year-old ...
Cecil Kim M - - 2002
Proton magnetic resonance spectroscopy (MRS) revealed a distinct resonance at 3.15 ppm in the brain of a 5-year-old male diagnosed with autism. The resonance assignment is attributable to ingestion of methylsulfonylmethane (MSM) as a dietary supplement. Glucosamine with MSM is marketed as a source of dietary sulfur and treatment of ...
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Kaminogo Makio - - 2002
With the current prevalence of tuberculosis, the incidence of intracranial tuberculoma may be on the rise in industrialized nations. However, clinical findings suggestive of systemic tuberculosis are frequently subtle or absent in patients with intracranial tuberculoma, and no specific neuroradiologic characteristics of tuberculoma have been defined as yet. We report ...
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Van Huffel Sabine - - 2002
Several algorithms for automatic frequency alignment and quantitation of single resonances in multiple magnetic resonance (MR) spectra are investigated. First, a careful comparison between the complex principal component analysis (PCA) and the Hankel total least squares-based methods for quantifying the resonances in the spectral sets of magnetic resonance spectroscopy imaging ...
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Rumpel Helmut - - 2002
This article reports on the use of both magnetization-transfer (MT) imaging and 1H-MR spectroscopy in two cases of bilateral temporal-lobe changes after radiation therapy for nasopharyngeal carcinoma. In the first case, the following patterns were noted: (i) although the temporal lobes appeared relatively normal on T2-weighted MR imaging, corresponding MT ...
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Greco J B - - 2002
The purpose of our study was to demonstrate the feasibility of using in vivo proton Magnetic Resonance Spectroscopy (MRS) to monitor the brain manifestations of SIV infection in the macaque model of AIDS. Previous spectroscopy work on macaque brain tissue and in vivo work in humans is reviewed to provide ...
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Schwarcz A - - 2002
BACKGROUND: In vivo water content determination based on magnetic resonance (MR) method is of importance in clinical practice as well as in animal studies to follow up the treatment given in order to reduce brain oedema. The methods proposed in the literature so far are largely time consuming. The aim ...
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Viola Angèle - - 2002
Nonketotic hyperglycinemia is a life-threatening disorder in neonates characterized by a deficiency of the glycine cleavage system. We report on four cases of the neonatal form of the disease, which were investigated by in vitro(1)H magnetic resonance spectroscopy of blood and cerebrospinal fluid, and in vivo(1)H magnetic resonance spectroscopy of ...
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Malik G K - - 2002
INTRODUCTION: A number of studies have suggested the potential utility of in vivo proton MR spectroscopy for the evaluation of brain injury in the asphyxiated neonates. We present our initial experience with in vivo proton MR spectroscopy in neonates who were diagnosed as having hypoxic injury on clinical examination and ...
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Gupta Rakesh K - - 2002
We have compared and analyzed the value of in vivo proton MR spectroscopy (PMRS) and T1 weighted magnetization transfer (MT) MR imaging in tissue characterization of brain tuberculomas. We studied 33 cases of proven intracranial tuberculomas with in vivo PMRS and T1 weighted MT MR imaging. MT ratios from the ...
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Shukla-Dave Amita - - 2002
RATIONALE AND OBJECTIVES: Combinations of chemotherapy and fractionated radiation therapy are the currently preferred nonsurgical treatment methods for squamous cell carcinoma of the head and neck, but to the authors' knowledge there is no reliable marker for predicting therapeutic response. Early identification of nonresponders would allow prompt replacement of ineffective, ...
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Wolinsky Jerry S - - 2002
Magnetic resonance spectroscopy provides noninvasive insight into the regional and global biochemical alterations that are concomitants of the dynamic processes that underlie the evolution of fundamental pathologic changes in multiple sclerosis. These include now well-recognized alterations of neuronal biochemical markers that accompany tissue destruction readily visualized by magnetic resonance imaging, ...
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