Abstract:
:The possibility of quantifying the superimposed signal of glutamate and glutamine (Glx) and its components by ¹H magnetic resonance spectroscopy (MRS) in the spinal cord is an exciting challenge with important clinical applications in neurological conditions. The spinal cord is a particularly difficult region of interest due to its small volume, magnetic field inhomogeneities and physiological motion. In this study, we investigated for the first time the feasibility of obtaining quantitative measurements of Glx in healthy cervical spinal cord by ¹H MRS at 3 T. The aim of this study was to compare two commercially available MRS sequences by spectral simulations and in vivo. A short echo time (TE) point resolved spectroscopy (PRESS) with TE = 30 ms and a stimulated echo acquisition mode (STEAM) with TE = 11 ms and mixing time (TM) = 17 ms were compared for reliability of Glx fit. Data allowed us to determine sample size estimates for future clinical studies for the first time. Results showed that PRESS provided a reliable fit for Glx in all cases (Cramér Rao lower bounds < 20%) whereas no reliable Glx fits were achieved using STEAM. Neither protocol provided reliable Glu quantification. The power calculations showed that a minimum sample size of 17 subjects per group was needed to detect Glx changes of > 20% using the PRESS sequence. This study proposed a clinically feasible MRS method for Glx detection in the human cervical cord in vivo including sample sizes needed for conclusive clinical studies.
journal_name
NMR Biomedjournal_title
NMR in biomedicineauthors
Solanky BS,Abdel-Aziz K,Yiannakas MC,Berry AM,Ciccarelli O,Wheeler-Kingshott CAdoi
10.1002/nbm.2867subject
Has Abstractpub_date
2013-03-01 00:00:00pages
357-66issue
3eissn
0952-3480issn
1099-1492journal_volume
26pub_type
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journal_title:NMR in biomedicine
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pub_type: 杂志文章
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更新日期:2008-03-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
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journal_title:NMR in biomedicine
pub_type: 杂志文章
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pub_type: 杂志文章
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更新日期:1995-05-01 00:00:00
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doi:10.1002/nbm.4439
更新日期:2020-11-17 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/(sici)1099-1492(199806/08)11:4/5<157::aid-
更新日期:1998-06-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3309
更新日期:2015-06-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.2767
更新日期:2012-08-01 00:00:00
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更新日期:2005-12-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
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更新日期:2020-10-01 00:00:00
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pub_type: 杂志文章
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/(sici)1099-1492(199902)12:1<51::aid-nbm546
更新日期:1999-02-01 00:00:00
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pub_type: 杂志文章
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journal_title:NMR in biomedicine
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更新日期:2016-09-01 00:00:00