Magnetic resonance angiography with hyperpolarized 129Xe dissolved in a lipid emulsion.
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.
Möller
H E
HE
Center for In Vivo Microscopy, Duke University Medical Center, Durham, North Carolina, USA. moeller@uni-muenster.de
Chawla
M S
MS
Chen
X J
XJ
Driehuys
B
B
Hedlund
L W
LW
Wheeler
C T
CT
Johnson
G A
GA
D000005:Abdomen / Q000098:blood supply; D000818:Animals; D016477:Artifacts; D001783:Blood Flow Velocity; D001810:Blood Volume; D003287:Contrast Media / Q000008:administration & dosage; D004578:Electron Spin Resonance Spectroscopy; D005217:Fat Emulsions, Intravenous / Q000008:administration & dosage; D007084:Iliac Vein / Q000033:anatomy & histology; D007275:Injections, Intravenous; D007834:Lasers; D018810:Magnetic Resonance Angiography / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D010388:Pelvis / Q000098:blood supply; D051381:Rats; D012082:Renal Veins / Q000033:anatomy & histology; D012815:Signal Processing, Computer-Assisted; D014680:Veins / Q000033:anatomy & histology; D014682:Vena Cava, Inferior / Q000033:anatomy & histology; D014979:Xenon Isotopes
D003287:Contrast Media; D005217:Fat Emulsions, Intravenous; D014979:Xenon Isotopes