## Abstract Comprehensive and quantitative measurements of __T__~1~ and __T__~2~ relaxation times of water, metabolites, and macromolecules in rat brain under similar experimental conditions at three high magnetic field strengths (4.0 T, 9.4 T, and 11.7 T) are presented. Water relaxation showed a h
Multiple field strength in vivo T1 and T2 for cerebrospinal fluid protons
β Scribed by A. L. Hopkins; H. N. Yeung; C. B. Bratton
- Publisher
- John Wiley and Sons
- Year
- 1986
- Tongue
- English
- Weight
- 548 KB
- Volume
- 3
- Category
- Article
- ISSN
- 0740-3194
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β¦ Synopsis
To estimate the feasibility of measuring in vivo CSF protein, oxygen, or other solutes through their effect on proton relaxation times, the TI and T2 of CSF protons has been measured within the human lateral ventricles. T I was measured at 6.25, 25.4, and 60.1 MHz with a two-point method. T, was measured at 6.25 and 25.4 MHz using the CPMG sequence to acquire 8 echo images. The T I was 4.3 s with no evidence of field dependence. The T2 was 2 s. Although these values approach those for water at the same temperature it is possible that the T I is influenced by the normal oxygen concentration. Calculations based on the relaxivity of dissolved protein indicate that the use of these methods for the detection of elevated levels of CSF protein would be less sensitive than existing methods.
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