NMR spin-lattice relaxation in tissues with high concentration of paramagnetic contrast media: evaluation of water exchange rates in intact rat muscle.
High concentrations of GdDTPA in extracellular water of tissue cause the intrinsic relaxation rate of water to become greater than the coupling rate between intracellular and extracellular water compartments. The fast exchange limit is no longer valid and distinctly nonexponential spin-lattice recovery is observed. T1 relaxation recovery was characterized by a double exponential curve when striated rat muscle was immersed in a highly concentrated (110 Mm) isotonic solution of GdDTPA. When the water exchange rate through cell membranes in intact muscle tissue was calculated (using a two-compartment exchange model) and compared to similar data determined from T2 Carr-Purcell-Meiboom-Gill experiments, a significant discrepancy was found.
Sobol
W T
WT
Department of Radiology, Bowman Gray School of Medicine, Winston-Salem, North Carolina 27103.
Jackels
S C
SC
Cothran
R L
RL
Hinson
W H
WH
D000818:Animals; D001834:Body Water / Q000378:metabolism*; D003287:Contrast Media; D019786:Gadolinium DTPA; D009682:Magnetic Resonance Spectroscopy; D009132:Muscles / Q000378:metabolism*; D009942:Organometallic Compounds; D004369:Pentetic Acid; D051381:Rats; D011916:Rats, Inbred F344
D003287:Contrast Media; D009942:Organometallic Compounds; D004369:Pentetic Acid; D019786:Gadolinium DTPA