Send to

Choose Destination
Magn Reson Med. 2003 Apr;49(4):620-5.

Relaxation times of 31P-metabolites in human calf muscle at 3 T.

Author information

NMR Group, Department of Medical Physics, Vienna University, Währingerstrasse 13, A-1090 Vienna, Austria.


Localized (31)P-STEAM experiments were performed at 3 T to estimate relaxation times of phosphorus-containing metabolites in the human calf muscle in vivo. T(1) and T(2) times of PCr, P(i), and NTPs were measured in the resting calf muscle of healthy subjects by varying TR and TE. The localization performance of the (31)P-STEAM sequence was evaluated on a test object, resulting in a relative selection efficiency of 78 +/- 1% and contamination from outside the voxel of 0 +/- 2% under fully relaxed conditions. T(1) relaxation times (+/-SD, n = 5) of P(i), PCr, gamma-NTP, alpha-NTP, and beta-NTP obtained at 3 T are 5.2 +/- 1.0 s, 6.4 +/- 0.2 s, 4.5 +/- 0.3 s, 2.6 +/- 0.9 s, and 3.5 +/- 1.1 s, respectively. T(2) relaxation times (+/-SD, n = 6) of these metabolites are 148 +/- 17 ms, 334 +/- 30 ms, 78 +/- 13 ms, 55 +/- 7 ms, and 55 +/- 10 ms, respectively. Spin-lattice relaxation times established at 3 T are consistent with literature data at lower field strengths, whereas spin-spin relaxation times are lower. Several methodological considerations are discussed which may help improve quantification of metabolite concentrations in the human (calf) muscle in vivo by using localized noninvasive (31)P-MRS at 3 T, which is currently being tested for routine clinical applications.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center