Abstract:
:1H MR spectra were recorded from human gastrocnemius muscle at 63.86 MHz using the body coil of the Signa scanner as transmitter and a 3-in. surface coil as receiver. The fat content of the muscle was quantified relative to that of water in a selected volume or slice. The fat/water ratio was 0.05-0.07 for normal muscle but increased to 0.5-6.0 in primary and secondary muscular disorders such as Duchenne and myotonic dystrophy, Charcot-Marie-Tooth and polio muscular atrophy, cerebral palsy, and spina bifida. In Werdnig-Hoffmann spinal atrophy the ratio was above 10. Water-suppressed and slice-selective 1H spectroscopy was used for qualitative analysis of fat. The 1H profile of gastrocnemius muscles between healthy individuals and patients with neuromuscular diseases showed two major differences. In the normal muscle spectra, the resonance from the -(CH2)n- protons at 1.6 ppm was the most pronounced, whereas in the diseased muscle spectra resonances also appeared between 1.1 and 1.4 ppm. Some diseased muscle spectra showed multiple resonances from -CH = CH- in polyunsaturated fatty acids between 5.5 and 7.0 ppm. The corresponding resonances from = CH-CH2-, 1.9-2.0 ppm, and = CH-CH2-CH =, 2.7-2.9 ppm, were also seen. These peaks are usually not detected in normal muscle.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Bárány M,Venkatasubramanian PN,Mok E,Siegel IM,Abraham E,Wycliffe ND,Mafee MFdoi
10.1002/mrm.1910100206subject
Has Abstractpub_date
1989-05-01 00:00:00pages
210-26issue
2eissn
0740-3194issn
1522-2594journal_volume
10pub_type
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