Myoinositol resonances

Valproate-induced hyperammonemic encephalopathy has been reviewed (1177). Proton magnetic resonance spectroscopy was performed in a patient with valproate-induced hyperammonemic encephalopathy there was a significant fall in the choline and myoinositol resonances and an increase in glutamine in the hyperintense basal ganglia lesions (1178). A similar pattern has been observed in other hyperammonemic encephalopathies, such as hepatic encephalopathy. In another study in seven patients with valproate-related hyperammonemia serum or cerebrospinal fluid glutamine concentrations were initially raised in most patients, sometimes in the absence of hyperammonemia (1179). 

Magnetic resonance spectroscopy (MRS) This technique is also referred to as magnetic resonance spectroscopy imaging (MRS ) or volume-selective NMR spectroscopy, which basically combines MRI with NMR spectroscopy. Thus MRS allows conventional MRI study of a body region, while NMR spectroscopy provides information on the biomolecules in that same region. This is a powerful tool, which can be used to provide spectral data on metabolites including lactate, choline, creatinine and myoinositol. 

Frey, R., Metzler, D., Fischer, P., Heiden, A., Scharfetter, J., Moser, E., and Kasper, S. 1998, Myoinositol in depressive and healthy subjects determined by frontal H-magnetic resonance spectroscopy at 1.5 tesla. J. Psychaitr. Res., 32 411—420. 

The Pad6-reconstructed absorption component shape spectra for the normal glandular prostate are shown in Figure 6.18 at Np = 54 and Np = 800. The upper panel reveals that at Np = 54, only 12 of fhe 27 resonances were resolved. These correctly resolved peaks were mainly at the two extremes of the spectrum (lactate and alanine at 1.33 and 1.49 ppm and myoinositol... 

Figure 6 A H MRS spectrum from normal human brain at 7T. An 8 ml VOI was localized in the parietal white matter using STEAM with effective TE 6 ms, repetition time 5 s, TM 32 ms, and the collection of 160 averaged echoes. Outer volume suppression, employing SECH pulses, was used and FASTMAP was used to shim the VOI. Peaks undefined in the main text are myoinositol - myo-lns taurine - Tau glutathione - GSH aspartate -ASP A/-acetylaspartylglutamate - NAAG macromolecule - MM. (Reprinted with permission from Tkac I, Anderson P, Adriany G, et at. (2001) In vivo NMR spectroscopy of the human brain at 7 Tesla. Magnetic Resonance in Medicine 46 451-456 Wiley-Liss, a subsidiary of Wiley.)...

Forester BP, Finn CT, Berlow YA, Wardrop M, Renshaw PF, Moore CM. Brain lithium, N-acetyl aspartate and myoinositol levels in older adults with bipolar disorder treated with lithium a lithium-7 and proton magnetic resonance spectroscopy study. Bipolar Disord 2008 10(6) 691-700. 

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