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Spatial localization techniques are necessary for in vivo NMR spectroscopy involving heterogeneous organisms. Localization by surface coil NMR detection alone is generally inadequate for deep-lying organs due to contaminating signals from intervening surface tissues. However, localization to preselected planar volumes can be accomplished using a single(More)
A nuclear magnetic resonance (NMR) imaging system signal-to-noise calibration technique based on an NMR projection of distilled water in a cylindrical bottle is proposed. This measurement can characterize any arrangement of rf coils in any magnetic field as signal to noise per ml times root Hz. Inductive losses in a typical patient must be included in the(More)
BACKGROUND The progression of pressure-overload left ventricular hypertrophy (LVH) to chronic heart failure (CHF) may involve a relative deficit in energy supply and/or delivery. METHODS AND RESULTS We measured myocardial creatine kinase (CK) metabolite concentrations and adenosine triphosphate (ATP) synthesis through CK, the primary energy reserve of the(More)
The heart consumes more energy per gram than any other organ, and the creatine kinase (CK) reaction serves as its prime energy reserve. Because chemical energy is required to fuel systolic and diastolic function, the question of whether the failing heart is "energy starved" has been debated for decades. Despite the central role of the CK reaction in cardiac(More)
PURPOSE To investigate the diagnostic value of proton magnetic resonance spectroscopic imaging (MRSI) in patients with breast lesions. MATERIALS AND METHODS Eighteen patients underwent breast MRSI and MRI at 1.5 T. Contrast-enhanced MR was used to identify the lesion, after which single-slice MRSI (TR/TE = 2000/272 msec, 10-mm slice thickness) was(More)
BACKGROUND Preserved energy metabolism is essential for myocardial viability and the creatine kinase reaction is central to energy production and reserve. Although the appearance of myocardial creatine kinase enzyme in the blood is widely used to diagnose cardiac necrosis, there are no non-invasive ways to measure local creatine concentrations in the(More)
PURPOSE To develop image-guided spatially localized magnetic resonance (MR) spectroscopy to provide a noninvasive quantitative probe of myocardial creatine kinase (CK) metabolism, and to use it to determine the extent of changes in CK energy metabolism in nonviable infarcted canine myocardium. MATERIALS AND METHODS Water-referenced localized phosphorus(More)
The longitudinal (T1) and transverse (T2) proton (1H) nuclear magnetic resonance (NMR) relaxation times of pathological human and animal tissues in the frequency range 1-100 MHz are archived, reviewed, and analyzed as a function of tissue of origin, NMR frequency, temperature, species, and in vivo versus in vitro status. T1 data from specific disease states(More)
PURPOSE To use sodium 23 magnetic resonance (MR) imaging to quantify noninvasively total sodium in human muscle and to apply the technique in exercise and musculoskeletal disease. MATERIALS AND METHODS Total [Na] sodium was determined from the ratio of the relaxation-corrected (23)Na signal intensities measured from short echo-time (0.4 msec) (23)Na(More)
The homogeneity and stability of the static magnetic field are of paramount importance to the accuracy of MR procedures that are sensitive to phase errors and magnetic field inhomogeneity. It is shown that intense gradient utilization in clinical horizontal-bore superconducting MR scanners of three different vendors results in main magnetic fields that vary(More)