Abstract:
:Hyperpolarized (HP) 129Xe can be dissolved in biologically compatible lipid emulsions while maintaining sufficient polarization for in vivo vascular imaging. For xenon in Intralipid 30%, in vitro spectroscopy at 2 T yielded a chemical shift of 197 +/- 1 ppm with reference to xenon gas, a spin-lattice relaxation time T1 = 25.3 +/- 2.1 sec, and a T2* time constant of 37 +/- 5 msec. Angiograms of the abdominal and pelvic veins in the rat obtained with 129Xe MRI after intravenous injection of HP 129Xe/Intralipid 30% into the tail demonstrated signal-to-noise ratios between 8 and 29. An analysis of the inflow effect on time-of-flight images of two segments of the inferior vena cava yielded additional information. The mean blood flow velocity was 34.7 +/- 1.0 mm/sec between the junction of the caudal veins and the kidneys and 13.3 +/- 0.8 mm/sec at the position of the diaphragm. The mean volume flow rates in these segments were 7.2 +/- 3.4 ml/min and 11.0 +/- 2.8 ml/min, respectively. Intravenous delivery of HP 129Xe dissolved in a carrier may lead to novel biomedical applications of laser-polarized gases.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Möller HE,Chawla MS,Chen XJ,Driehuys B,Hedlund LW,Wheeler CT,Johnson GAdoi
10.1002/(sici)1522-2594(199905)41:5<1058::aid-mrm2subject
Has Abstractpub_date
1999-05-01 00:00:00pages
1058-64issue
5eissn
0740-3194issn
1522-2594pii
10.1002/(SICI)1522-2594(199905)41:5<1058::AID-MRM2journal_volume
41pub_type
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