Spatial localization in 31P and 13C NMR spectroscopy in Vivo using surface coils

Bottomley, Paul A.; Edelstein, William A.; Hart, H. R.; Schenck, John F.; Smith, L.S.

doi:10.1002/mrm.1910010311

Cited by 37 publications

(9 citation statements)

References 13 publications

(4 reference statements)

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“…A 10-cm, transmit-receive surface coil was positioned over the heart. An image-selective in vivo spectroscopy (ISIS) sequence 10 was used in the Philips system and the oblique depth-resolved spectroscopy (DRESS) 11 with a modified FIDCSI sequence from a 25-mm-thick slice was used in the General Electric system. MRS data were acquired from a region that maximized signal from the heart muscle while minimizing that from skeletal muscle.…”

Section: Phosphorus-31 Mrsmentioning

confidence: 99%

Prognosis in Women With Myocardial Ischemia in the Absence of Obstructive Coronary Disease

et al. 2004

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Background-We previously reported that 20% of women with chest pain but without obstructive coronary artery disease (CAD) had stress-induced reduction in myocardial phosphocreatine-adenosine triphosphate ratio by phosphorus-31 nuclear magnetic resonance spectroscopy (abnormal MRS), consistent with myocardial ischemia. The prognostic implications of these findings are unknown. Methods and Results-Women referred for coronary angiography for suspected myocardial ischemia underwent MRS handgrip stress testing and follow-up evaluation. These included (1) nϭ60 with no CAD/normal MRS, (2) nϭ14 with no CAD/abnormal MRS, and (3) nϭ352 a reference group with CAD. Cardiovascular events were death, myocardial infarction, heart failure, stroke, other vascular events, and hospitalization for unstable angina. Cumulative freedom from events at 3 years was 87%, 57%, and 52% for women with no CAD/normal MRS, no CAD/abnormal MRS, and CAD, respectively (PϽ0.01). After adjusting for CAD and cardiac risk factors, a phosphocreatine-adenosine triphosphate ratio decrease of 1% increased the risk of a cardiovascular event by 4% (Pϭ0.02). The higher event rate in women with no CAD/abnormal MRS was primarily due to hospitalization for unstable angina, which is associated with repeat catheterization and higher healthcare costs. Conclusions-Among women without CAD, abnormal MRS consistent with myocardial ischemia predicted cardiovascular outcome, notably higher rates of anginal hospitalization, repeat catheterization, and greater treatment costs. Further evaluation into the underlying pathophysiology and possible treatment options for women with evidence of myocardial ischemia but without CAD is indicated.

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Section: Phosphorus-31 Mrsmentioning

confidence: 99%

Prognosis in Women With Myocardial Ischemia in the Absence of Obstructive Coronary Disease

et al. 2004

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“…31P NMR spectra have also been recorded from surface coils located on the chests of infants without provision for spatial localization to the heart muscle (17). Contamination of surface coil spectra by surface tissue has been emphasized by many investigators as a major problem with the latter technique (6,(9)(10)(11)(12)(13)(14)(15)(16)(18)(19)(20)(21).…”

mentioning

confidence: 99%

“…All NMR data were acquired synchronously with diastole and at the end of respiratory expiration intervals, except under conditions of cardiac fibrillation or arrest. In order to correctly position the surface coil relative to the heart and to estimate the depth of the coronal slice that contained the jeopardized myocardium, 1H imaging in transaxial, sagittal, and coronal planes was first performed with a whole-body transmitter and a surface-detection coil (diameter, 6.5 cm) prior to occlusion (20,22). Next, 1H spectroscopy was performed on the selected slice by the DRESS technique (21).…”

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confidence: 99%

Noninvasive detection and monitoring of regional myocardial ischemia in situ using depth-resolved 31P NMR spectroscopy.

Bottomley¹,

Herfkens²,

Smith³

et al. 1985

Proc. Natl. Acad. Sci. U.S.A.

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Phosphorus (31P) NMR spectra showing the relative concentrations of phosphocreatine, ATP, and Pi were recorded noninvasively from localized regions in the left ventricles of dog hearts in situ by using depth-resolved surfacecoil spectroscopy at 1.5 T. Proton (1H) NMR surface-coil imaging was used to position 31P NMR coils and to determine the location of depth-resolved volumes immediately prior to 31P examination. Occlusion of the left anterior descending coronary artery produced regional ischemia detected as changes in the ratios of phosphocreatine, ATP, and Pi and by changes in the pH measured from the spectra. Spectral changes were not typically observed in regions adjacent to ischemic myocardium. Reperfusion produced some recovery, and ventricular fibrillation resulted in deterioration in high-energy metabolites. The location and size of ischemic tissue was measured by singlephoton-emission computed tomography (SPECT) and gammaray counting or by staining excised hearts. The technique should permit the long-term noninvasive monitoring of the metabolic response of the heart to pathologic processes and allow assessment of interventions. NMR spectrum is a profile of the relative concentrations of the high-energy phosphate metabolites phosphocreatine (PCr) and ATP as well as inorganic phosphate, Pi (1-6). Such spectra are responsive to changes in myocardial metabolism as early as 90 s after the onset of ischemia (3). To date, applications of 31P NMR spectroscopy to heart metabolism have proved invasive because of (i) the difficulty of achieving adequate spatial localization of the 31p signal to the heart, and (ii) the small magnet apertures of available

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“…Spectra are acquired at 1.5 T in averaging periods of 2 s consistent with the expected sensitivity advantage of the 1H nucleus. Spectroscopy sequences are immediately followed by conventional planar imaging with the same NMR coils (28,29) to precisely determine the location and size of the spectroscopy volume element (voxel). Studies of the human arm and the head of a dog are also presented.…”

mentioning

confidence: 99%

In vivo solvent-suppressed localized hydrogen nuclear magnetic resonance spectroscopy: a window to metabolism?

Bottomley¹,

Edelstein²,

Foster³

et al. 1985

Proc. Natl. Acad. Sci. U.S.A.

104

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Solvent-suppression NMR techniques are combined with a pulsed magnetic field gradient and surface coil detection method of spatial localization. The result is a technique that enables observation of metabolites in the hydrogen (1H) NMR chemical-shift spectra from preselected disk-shaped volumes of biological tissue in vivo. Localized spectra are recorded from the normal human brain and forearm and from a dog in acquisition periods of 2 s using a 1.5-T imaging/spectroscopy system. This is several hundredfold faster than acquiring similar state-of-the-art 31P NMR spectra of brain metabolites in vivo. Spectroscopy experiments are followed by conventional surface coil imaging sequences to precisely defrne the selected volume. Contamination of spectra by lipid resonances is a problem.Localized phosphorus (31P) NMR is proving a valuable tool in the in vivo investigation of animal models of stroke (1-5), myocardial ischemia (6-8), tumors (9, 10), and the efficacy of drug therapy (11, 12) as well as human muscular metabolic diseases (13-15) and cerebral disorders in neonates (16). Its value resides in the ability to detect and monitor intracellular pH and in vivo concentrations of metabolites such as phosphocreatine (PCr), ATP, and Pi, which directly measure the state of health of tissue. A major impediment limiting utility of this technology in clinical medicine is the low sensitivity of the 31P resonance. Thus, data acquisition times are typically of the order 10 min for a single coarsely resolved localized volume of the order 20 cm3 in the currently available large-aperture, 1.5-to 2-T, magnet-based spectroscopy systems (16)(17)(18).Nucleus for nucleus, the hydrogen (1H) resonance offers a 15-fold improvement in signal-to-noise ratio (19, 20) or a reduction by a factor of 227 in signal averaging time over 31p NMR at the same magnetic field strength. 1H NMR spectra can reveal the relative concentrations of the total PCr/creatine (Cr) pool, phosphocholine (PCho), N-acetylaspartate (N-AcAsp), some lipid (-CHY-), and lactate metabolites.Such resonances have been detected in vivo in rat brain (21) and isolated perfused heart spectra at 8.5 T (22) and recently in rabbit brain at 1.9 T (23), all with spectral averaging times of 2-2.5 min and sample volumes of the order 1-10 cm3. The amplitude of the lactate (-CH3) resonance appears as sensitive to hypoxia and ischemia as the Pi resonance in 31p spectra and contains 3-fold as many nuclei. Thus, localized in vivo 1H NMR spectroscopy could provide spectacular sensitivity/scan time advantages over 31p for certain metabolic studies and clinical applications.Key difficulties encountered with the implementation of in vivo 1H metabolic spectroscopy are the suppression of H20 and lipid -CH2-resonances (21-23) and the method of spatial localization. The H20 resonance is of order 10,000-fold more intense than the metabolites and normally swamps the spectrum. Solvent-suppression techniques that rely on avoiding excitation of the H20 resonance (24) are unsuitable for localized...

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Spatial localization in ³¹P and ¹³C NMR spectroscopy in Vivo using surface coils

Cited by 37 publications

References 13 publications

Prognosis in Women With Myocardial Ischemia in the Absence of Obstructive Coronary Disease

Prognosis in Women With Myocardial Ischemia in the Absence of Obstructive Coronary Disease

Noninvasive detection and monitoring of regional myocardial ischemia in situ using depth-resolved 31P NMR spectroscopy.

In vivo solvent-suppressed localized hydrogen nuclear magnetic resonance spectroscopy: a window to metabolism?

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