Characterization of the NMR behavior of white matter in bovine brain

In vitro experiments on 15 white matter samples from five bovine brains were performed on a 1H‐NMR spectrometer at 24°C and 37°C. The average myelin water fractions (MWFs) were 10.9% and 11.8% for samples at 24°C and 37°C, respectively. The T1 relaxation time at 37°C was found to be 830 ms, exhibiti...

Full description

Saved in:
Bibliographic Details
Published in:Magnetic resonance in medicine Vol. 54; no. 5; pp. 1072 - 1081
Main Authors: Bjarnason, T.A., Vavasour, I.M., Chia, C.L.L., MacKay, A.L.
Format: Journal Article
Language:English
Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01-11-2005
Subjects:
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In vitro experiments on 15 white matter samples from five bovine brains were performed on a 1H‐NMR spectrometer at 24°C and 37°C. The average myelin water fractions (MWFs) were 10.9% and 11.8% for samples at 24°C and 37°C, respectively. The T1 relaxation time at 37°C was found to be 830 ms, exhibiting monoexponential behavior. A four‐pool model including intra/extracellular (IE) water, myelin water, nonmyelin tissue, and myelin tissue was proposed to simulate the NMR behavior of bovine white matter. A cross‐relaxation correction was introduced to compensate for shifting of the measured data points and T2 times over the duration of the Carr‐Purcell‐Meiboom‐Gill (CPMG) measurement due to cross relaxation. This correction was found to be slight, providing evidence that MWFs measured using a multiecho technique are near physical values. At 24°C the cross‐relaxation times between myelin tissue and myelin water, myelin water and IE water, and IE water and nonmyelin tissue were found to be approximately 227, 2064, and 402 ms, respectively. At 37°C these same cross‐relaxation times were 158, 1021, and 170 ms, respectively. The exchange rate between myelin water and myelin was found to be 11.8 s−1 at 37°C, while the exchange rate between IE water and nonmyelin tissue was found to be 6.8 s−1. These exchange rates are of similar magnitude, which indicates that the interaction between IE water and nonmyelin tissue cannot be ignored. Magn Reson Med, 2005. © 2005 Wiley‐Liss, Inc.
Bibliography:Natural Sciences and Engineering Research Council of Canada
ArticleID:MRM20680
ark:/67375/WNG-952SH4ZC-Z
Multiple Sclerosis Society of Canada
istex:E6235D238DBEF44D637DAE51E69F58459653D912
ObjectType-Article-2
SourceType-Scholarly Journals-1
ObjectType-Feature-1
content type line 23
ObjectType-Article-1
ObjectType-Feature-2
ISSN:0740-3194
1522-2594
DOI:10.1002/mrm.20680