title: Noninvasive measurement of renal hemodynamic functions using gadolinium enhanced magnetic resonance imaging.
abstract: A technique for the assessment of single kidney hemodynamic functions utilizing a novel MR pulse sequence in conjunction with MR contrast material administration is described. Renal extraction fraction (EF) is derived by measuring the concentration of the incoming contrast agent in the renal artery and the outgoing concentration in the renal vein. The glomerular filtration rate (GFR) can then be determined by the product of EF and renal plasma flow. A modified inversion recovery MR pulse sequence is used to measure the T1 of moving blood. This pulse sequence uses a spatially nonselective inversion pulse. A series of small flip angle detection pulses are then used to monitor the recovery of longitudinal spin magnetization in an image plane intersecting the renal vessels. The recovery rate is measured in each vessel and the T1 of blood determined. These T1 measurements are then used to determine the ratio of contrast concentration in the renal arteries and veins. Blood flow measurements can be obtained simultaneously with T1 measurements by inserting flow-encoding magnetic field gradients into the pulse sequence. Preliminary results in human volunteers suggest the feasibility of noninvasively determining hemodynamic functions with magnetic resonance.
authors.affiliation: General Electric Research and Development Center, Schenectady, New York.
authors.forename: C L
authors.initials: CL
authors.lastname: Dumoulin
authors.forename: M H
authors.initials: MH
authors.lastname: Buonocore
authors.forename: L R
authors.initials: LR
authors.lastname: Opsahl
authors.forename: R W
authors.initials: RW
authors.lastname: Katzberg
authors.forename: R D
authors.initials: RD
authors.lastname: Darrow
authors.forename: T W
authors.initials: TW
authors.lastname: Morris
authors.forename: C
authors.initials: C
authors.lastname: Batey
mesh_terms: D000465:Algorithms; D001783:Blood Flow Velocity / Q000502:physiology; D003287:Contrast Media; D005682:Gadolinium; D019786:Gadolinium DTPA; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007668:Kidney / Q000502:physiology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008961:Models, Structural; D009942:Organometallic Compounds; D004369:Pentetic Acid / Q000031:analogs & derivatives*; D012039:Regional Blood Flow / Q000502:physiology; D012077:Renal Artery / Q000502:physiology; D012079:Renal Circulation / Q000502:physiology*; D017595:Renal Plasma Flow / Q000502:physiology*; D012082:Renal Veins / Q000502:physiology
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; D004369:Pentetic Acid; D005682:Gadolinium; D019786:Gadolinium DTPA