Abstract：
:Proton NMR spectroscopy was applied to quantitate the measurement of total body water/fat distributions in vivo. A special MR protocol was developed to excite a thick slab of tissue and display the magnitude NMR spectrum of the collected response signal. Very short echo time TE (8 ms) and long repetition time TR (4000 ms) were used to minimize relaxation damping of the signal intensities. The spectrum was then decomposed into individual lines and proton densities of different species were calculated. Proton density information was converted into weight percentage data using stoichiometrical and physiological information. The technique was validated using phantoms that contained different mixtures of water/maize oil. A high-resolution NMR spectrum of maize oil samples was used to determine the stoichiometric information. The test results showed good agreement with the known composition of the phantom within the whole range of water content (0-100%). This method is very fast since no phase encoding of data is required. Preliminary results for monkeys show promising potential in clinical applications.
journal_name
Med Physjournal_title
Medical physicsauthors
Sobol WT,Elster AD,Hinson WH,Chwals WJdoi
10.1118/1.596935subject
Has Abstractpub_date
1992-01-01 00:00:00pages
61-9issue
1eissn
0094-2405issn
2473-4209journal_volume
19pub_type
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