Abstract:
:High-energy phosphate metabolism, which allows the synthesis and regeneration of adenosine triphosphate (ATP), is a vital process for neuronal survival and activity. In particular, creatine kinase (CK) serves as an energy reservoir for the rapid buffering of ATP levels. Altered CK enzyme activity, reflecting compromised high-energy phosphate metabolism or mitochondrial dysfunction in the brain, can be assessed using magnetization transfer (MT) MRS. MT (31)P MRS has been used to measure the forward CK reaction rate in animal and human brain, employing a surface radiofrequency coil. However, long acquisition times and excessive radiofrequency irradiation prevent these methods from being used routinely for clinical evaluations. In this article, a new MT (31)P MRS method is presented, which can be practically used to measure the CK forward reaction rate constant in a clinical MRI system employing a volume head (31)P coil for spatial localization, without contamination from the scalp muscle, and an acquisition time of 30 min. Other advantages associated with the method include radiofrequency homogeneity within the regions of interest of the brain using a volume coil with image-selected in vivo spectroscopy localization, and reduction of the specific absorption rate using nonadiabatic radiofrequency pulses for MT saturation. The mean value of k(f) was measured as 0.320 ± 0.075 s(-1) from 10 healthy volunteers with an age range of 18-40 years. These values are consistent with those obtained using earlier methods, and the technique may be used routinely to evaluate energetic processes in the brain on a clinical MRI system.
journal_name
NMR Biomedjournal_title
NMR in biomedicineauthors
Jeong EK,Sung YH,Kim SE,Zuo C,Shi X,Mellon EA,Renshaw PFdoi
10.1002/nbm.1636subject
Has Abstractpub_date
2011-08-01 00:00:00pages
765-70issue
7eissn
0952-3480issn
1099-1492journal_volume
24pub_type
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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,评审
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journal_title:NMR in biomedicine
pub_type: 杂志文章
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journal_title:NMR in biomedicine
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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
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1727
更新日期:2012-01-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章,多中心研究
doi:10.1002/nbm.3252
更新日期:2015-03-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
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更新日期:2012-08-01 00:00:00
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journal_title:NMR in biomedicine
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doi:10.1002/nbm.3690
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3346
更新日期:2015-08-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3048
更新日期:2014-02-01 00:00:00
abstract::The performance of multichannel transmit coil layouts and parallel transmission (pTx) RF pulse design was evaluated with respect to transmit B1 (B1 (+)) homogeneity and specific absorption rate (SAR) at 3 T for a whole body coil. Five specific coils were modeled and compared: a 32-rung birdcage body coil (driven eithe...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3378
更新日期:2015-10-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4195
更新日期:2020-03-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
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pub_type: 临床试验,杂志文章
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