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Paramagnetic agents for contrast-enhanced NMR imaging: A review
156
Magnetic Resonance Imaging 0 Volume 2, Number 2, 1984
this study is preliminary, but it appears that NMR demonstrates more accurately the degree of brain involvement in SLE than CT. Index Terms: Lupus erythematosus-Brain, diseases-Nuclear magnetic resonance-Computed tomography. J. Comput. Assist. Tomogr. 7:461; 1983 Nuclear Magnetic Resonance (NMR) Tomography of the Central Nervous System: Comparison of Two Imaging Sequences W. Huk,’ W. Heindel,’
M. Deimling,’
and E. Stetter’
Neurosurgical Hospital of the University of Erlangen, Nurnberg Medical School,’ Erlangen, West German-v; and Siemens Medical Engineering Group,’ Erlangen. West Germany A brief description of a nuclear magnetic resonance (NMR) imaging system and preliminary results from its clinical evaluation in the study of various central nervous system diseases are presented. Particular attention is paid to NMR capabilities for soft tissue discrimination, topographical demarcation, and specificity of diagnosis. Two imaging sequences were used: (a) Spin echo measurements with four sets of imaging parameters revealed the different appearances of normal and pathological structures. (b) Inversion recovery images showed marked gray-white matter contrast and clear depiction of pathological lesions. Finally, a number of measurements of longitudinal (T,) and transverse (T,) relaxation times of normal and pathological tissues were carried out. Index Terms: Nuclear magnetic resonance-Brain-Spine. J. Comput. Assist. Tomogr. 7:468; 1983 REVIEW AND OVERVIEW The Instrumentation Imaging S. R. Thomas’
of Nuclear Magnetic
Resonance
and J. L. Ackerman’
‘Department of Radiology, E465 Medical Science Building; ‘Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45267 A brief introduction is provided to the basic concepts of nuclear magnetic resonance (NMR) for the purpose of establishing a common level. The topics of review include: the quantum mechanical foundations of NMR; magnetization in a rotating frame; the macroscopic equations of motion (Bloch equations); relaxation times (T,, T,); free induction decay; Fourier transform spectroscopy, and, the principle of magnetic field gradient imaging. The overview of the instrumentation of NMR imaging includes: a functional description of the basic NMR spectrometer, quadrature phase detection; digitization, pulse programming and com-
puter control; magnet systems; gradient coils; and, radiofrequency coils. References are provided for more detailed study. Proceedings-Fifth Annual Conf, IEEE Eng. in Med. and Biol. Sot. Paramagnetic Agents Imaging: A Review
for Contrast-Enhanced
NMR
Val M. Runge,’ Jeffrey A. Clanton,’ Charles M. Lukehart.’ C. Leon Partain,’ A. Everette James, Jr.’ ‘Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232: ‘Department of Chemistry, Vanderbilt tUniversity, Nashville, TN 37232 The use of paramagnetic agents for contrast enhancement may extend the diagnostic potential of nuclear magnetic resonance (NMR) imaging. Proton relaxation is enhanced in targeted organ systems after either oral or intravenous administration of suitable paramagnetic agents. A decrease in T, and T?, the spinlattice and spin-spin relaxation times, can then be observed as an increase in signal intensity on NMR imaging. Initial investigations have focused on development of agents incorporating either paramagnetic ions or stable free radicals. Principles in development and application are illustrated with examples from experiments using the Vanderbilt Technicare 0.5 T NMR imager. Am. J. Roentg. 141:1209; 1983 Clinical Nuclear Magnetic Body
Resonance Imaging of the
Charles B. Higgins, Hedvig Hricak, Gordon Gamsu, Richard W. Webb, Albert A. Moss, Harry K. Genant, Kirk L. Moon, Robert C. Brasch, David Stark, Alexander R. Margulis Department of Radiology, San Francisco. CA
University of California,
NMR promises great advances in diagnosis and has delivered so much already that it is expected that in the future it will replace many applications of the currently used imaging modalities. Although x-ray computed tomography is continuing to advance in speed of scanning and resolving power, NMR will most likely soon eliminate its use in many studies of the central nervous system and also in many other areas of the body. The promise of combining topical spectroscopy with imaging is also exciting and should provide further information about metabolic processes of various organs. Progress in NMR is so rapid and the future is so bright that one of the great problems will be to develop a new breed of radiologists who are versatile in
Magnetic Resonance Imaging 0 Volume 2, Number 2, 1984
this study is preliminary, but it appears that NMR demonstrates more accurately the degree of brain involvement in SLE than CT. Index Terms: Lupus erythematosus-Brain, diseases-Nuclear magnetic resonance-Computed tomography. J. Comput. Assist. Tomogr. 7:461; 1983 Nuclear Magnetic Resonance (NMR) Tomography of the Central Nervous System: Comparison of Two Imaging Sequences W. Huk,’ W. Heindel,’
M. Deimling,’
and E. Stetter’
Neurosurgical Hospital of the University of Erlangen, Nurnberg Medical School,’ Erlangen, West German-v; and Siemens Medical Engineering Group,’ Erlangen. West Germany A brief description of a nuclear magnetic resonance (NMR) imaging system and preliminary results from its clinical evaluation in the study of various central nervous system diseases are presented. Particular attention is paid to NMR capabilities for soft tissue discrimination, topographical demarcation, and specificity of diagnosis. Two imaging sequences were used: (a) Spin echo measurements with four sets of imaging parameters revealed the different appearances of normal and pathological structures. (b) Inversion recovery images showed marked gray-white matter contrast and clear depiction of pathological lesions. Finally, a number of measurements of longitudinal (T,) and transverse (T,) relaxation times of normal and pathological tissues were carried out. Index Terms: Nuclear magnetic resonance-Brain-Spine. J. Comput. Assist. Tomogr. 7:468; 1983 REVIEW AND OVERVIEW The Instrumentation Imaging S. R. Thomas’
of Nuclear Magnetic
Resonance
and J. L. Ackerman’
‘Department of Radiology, E465 Medical Science Building; ‘Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45267 A brief introduction is provided to the basic concepts of nuclear magnetic resonance (NMR) for the purpose of establishing a common level. The topics of review include: the quantum mechanical foundations of NMR; magnetization in a rotating frame; the macroscopic equations of motion (Bloch equations); relaxation times (T,, T,); free induction decay; Fourier transform spectroscopy, and, the principle of magnetic field gradient imaging. The overview of the instrumentation of NMR imaging includes: a functional description of the basic NMR spectrometer, quadrature phase detection; digitization, pulse programming and com-
puter control; magnet systems; gradient coils; and, radiofrequency coils. References are provided for more detailed study. Proceedings-Fifth Annual Conf, IEEE Eng. in Med. and Biol. Sot. Paramagnetic Agents Imaging: A Review
for Contrast-Enhanced
NMR
Val M. Runge,’ Jeffrey A. Clanton,’ Charles M. Lukehart.’ C. Leon Partain,’ A. Everette James, Jr.’ ‘Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232: ‘Department of Chemistry, Vanderbilt tUniversity, Nashville, TN 37232 The use of paramagnetic agents for contrast enhancement may extend the diagnostic potential of nuclear magnetic resonance (NMR) imaging. Proton relaxation is enhanced in targeted organ systems after either oral or intravenous administration of suitable paramagnetic agents. A decrease in T, and T?, the spinlattice and spin-spin relaxation times, can then be observed as an increase in signal intensity on NMR imaging. Initial investigations have focused on development of agents incorporating either paramagnetic ions or stable free radicals. Principles in development and application are illustrated with examples from experiments using the Vanderbilt Technicare 0.5 T NMR imager. Am. J. Roentg. 141:1209; 1983 Clinical Nuclear Magnetic Body
Resonance Imaging of the
Charles B. Higgins, Hedvig Hricak, Gordon Gamsu, Richard W. Webb, Albert A. Moss, Harry K. Genant, Kirk L. Moon, Robert C. Brasch, David Stark, Alexander R. Margulis Department of Radiology, San Francisco. CA
University of California,
NMR promises great advances in diagnosis and has delivered so much already that it is expected that in the future it will replace many applications of the currently used imaging modalities. Although x-ray computed tomography is continuing to advance in speed of scanning and resolving power, NMR will most likely soon eliminate its use in many studies of the central nervous system and also in many other areas of the body. The promise of combining topical spectroscopy with imaging is also exciting and should provide further information about metabolic processes of various organs. Progress in NMR is so rapid and the future is so bright that one of the great problems will be to develop a new breed of radiologists who are versatile in