Congenital Absence of the Left Pericardium: Nuclear Magnetic Resonance and Other Imaging Techniques

1992 ◽  
Vol 6 (5) ◽  
pp. 304-312
Author(s):  
Severino Davolo Marani ◽  
Maria Cristiana Brunazzi ◽  
Angelo Cotogni ◽  
Giulio Cesaro ◽  
Giuseppe Nasi ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Imaging Techniques ◽  
Congenital Absence ◽  
Nuclear Magnetic

The Wellcome Foundation Lecture, 1984 Nuclear magnetic resonance imaging in medicine: physical principles

1985 ◽  
Vol 225 (1241) ◽  
pp. 399-410 ◽  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Imaging Techniques ◽  
Superconducting Magnets ◽  
Image Resolution ◽  
Three Dimensions ◽  
Human Anatomy ◽  
Proton Density ◽  
Computed Tomography Images ◽  
Nuclear Magnetic

In recent years nuclear magnetic resonance (n. m. r.) has become a means of providing excellent images of the interior of the human body which are proving useful in medical practice. The development of n. m. r. imaging, much of which was pioneered in Britain, is outlined. Proton image resolution of human anatomy is comparable with X-ray computed tomography images, but without the hazard of ionizing radiation. There is improved soft tissue discrimination and pathological contrast through the basic imaging parameters of the proton density and the relaxation times T 1 and T 2 , whose differences from one tissue to another are exploited by use of appropriate radiofrequency pulse sequences. Images may be obtained directly of transverse, coronal and sagittal sections of the head and body. Single slices or multiple slices may be imaged and imaging may be done in three dimensions. The lecture describes the more important imaging techniques and gives illustrative examples of images obtained. The efficient use of time in n. m. r. imaging is discussed, particularly mentioning the multiecho-multislice procedure and the development of real-time n. m. r. imaging. Magnetic field strengths in current use for proton n. m. r. imaging range from 0.02 to 2 T. At the lower end of the range resistive magnets are used, while for higher fields superconducting magnets are needed. A considerable improvement in image quality is obtained by use of special receiver coils.

scholarly journals Hydrocephaly Analysis Supported by Computerized Tomography and Nuclear Magnetic Resonance

2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Tong Zhang ◽  
Yawei Zhou ◽  
Guohua Su ◽  
Dianfeng Shi ◽  
Subash C. B. Gopinath ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Cerebrospinal Fluid ◽  
Magnetic Resonance ◽  
Ct Scan ◽  
Computerized Tomography ◽  
Accurate Result ◽  
Imaging Techniques ◽  
Biomarker Analysis ◽  
The Brain ◽  
Nuclear Magnetic

Hydrocephalus is widely known as “hydrocephaly” or “water in the brain,” a building up of abnormal cerebrospinal fluid in the brain ventricles. Due to this abnormality, the size of the head becomes larger and increases the pressure in the skull. This pressure compresses the brain and causes damage to the brain. Identification by imaging techniques on the hydrocephalus is mandatory to treat the disease. Various methods and equipment have been used to image the hydrocephalus. Among them, computerized tomography (CT) scan and nuclear magnetic resonance (NMR) are the most considered methods and gives accurate result of imaging. Apart from imaging, cerebrospinal fluid-based biomarkers are also used to identify the condition of hydrocephalus. This review is discussed on “hydrocephalus” and its imaging captured by CT scan and NMR to support the biomarker analysis.

An emerging technology: Nuclear magnetic resonance microscopy

1988 ◽  
Vol 46 ◽  
pp. 1000-1001
Author(s):  
M.J. Hennessy ◽  
E. Kwok
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Relaxation Times ◽  
Basic Research ◽  
Local Environment ◽  
Magnetic Resonance Images ◽  
Nmr Microscopy ◽  
Mri Scans ◽  
Temperature Relaxation ◽  
Nuclear Magnetic

Much progress in nuclear magnetic resonance microscope has been made in the last few years as a result of improved instrumentation and techniques being made available through basic research in magnetic resonance imaging (MRI) technologies for medicine. Nuclear magnetic resonance (NMR) was first observed in the hydrogen nucleus in water by Bloch, Purcell and Pound over 40 years ago. Today, in medicine, virtually all commercial MRI scans are made of water bound in tissue. This is also true for NMR microscopy, which has focussed mainly on biological applications. The reason water is the favored molecule for NMR is because water is,the most abundant molecule in biology. It is also the most NMR sensitive having the largest nuclear magnetic moment and having reasonable room temperature relaxation times (from 10 ms to 3 sec). The contrast seen in magnetic resonance images is due mostly to distribution of water relaxation times in sample which are extremely sensitive to the local environment.

Nuclear magnetic resonance microscopy

1989 ◽  
Vol 47 ◽  
pp. 828-829
Author(s):  
Paul C. Lauterbur
Keyword(s):  
Magnetic Field ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Magnetic Fields ◽  
Signal To Noise ◽  
Field Gradients ◽  
Useful Signal ◽  
Magnetic Field Gradients ◽  
Observation Times ◽  
Nuclear Magnetic

Nuclear magnetic resonance imaging can reach microscopic resolution, as was noted many years ago, but the first serious attempt to explore the limits of the possibilities was made by Hedges. Resolution is ultimately limited under most circumstances by the signal-to-noise ratio, which is greater for small radio receiver coils, high magnetic fields and long observation times. The strongest signals in biological applications are obtained from water protons; for the usual magnetic fields used in NMR experiments (2-14 tesla), receiver coils of one to several millimeters in diameter, and observation times of a number of minutes, the volume resolution will be limited to a few hundred or thousand cubic micrometers. The proportions of voxels may be freely chosen within wide limits by varying the details of the imaging procedure. For isotropic resolution, therefore, objects of the order of (10μm) may be distinguished.Because the spatial coordinates are encoded by magnetic field gradients, the NMR resonance frequency differences, which determine the potential spatial resolution, may be made very large. As noted above, however, the corresponding volumes may become too small to give useful signal-to-noise ratios. In the presence of magnetic field gradients there will also be a loss of signal strength and resolution because molecular diffusion causes the coherence of the NMR signal to decay more rapidly than it otherwise would. This phenomenon is especially important in microscopic imaging.

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