BACKGROUND The decision to perform coronary revascularization procedures may hinge on assessment of myocardial perfusion reserve. Blood oxygen level-dependent (BOLD) MRI is a potential method to detect the effects of regional variations in myocardial blood flow during vasodilation. METHODS AND RESULTS We imaged dogs (n=13) on a 1.5-T whole-body MRI… (More)
Our proof of principle results show the feasibility of quantifying myocardial blood volume (MBV) with the intravascular contrast agent MS-325. For severe stenoses in a canine model, stenosis zone MBV was higher than remote MBV at rest, and lower than remote during vasodilation.
The feasibility of detecting regional differences in myocardial blood flow based on the blood oxygen level-dependent (BOLD) effect was evaluated in vivo in dogs (N = 9) using a 3D T2-prepared segmented gradient-echo sequence at 1.5 T. Regional differences in myocardial blood flow were created by administering adenosine through a catheter placed in the left… (More)
This work compares intravenous (IV) versus fluoroscopy-guided transarterial intra-catheter (IC) delivery of iron oxide core-titanium dioxide shell nanoparticles (NPs) in vivo in VX2 model of liver cancer in rabbits. NPs coated with glucose and decorated with a peptide sequence from cortactin were administered to animals with developed VX2 liver cancer. Two… (More)
PURPOSE Myocardial perfusion can be quantified using the "dual bolus" technique, which uses two separate contrast boluses to avoid signal nonlinearity in the blood pool. This technique relies on knowing the precise ratio of contrast concentrations between the two boluses. In this study, we investigated the variability found in these ratios, as well as the… (More)
OBJECTIVES To evaluate the impact of correcting myocardial signal saturation on the accuracy of absolute myocardial blood flow (MBF) measurements. MATERIALS AND METHODS We performed 15 dual bolus first-pass perfusion studies in 7 dogs during global coronary vasodilation and variable degrees of coronary artery stenosis. We compared microsphere MBF to MBF… (More)
Creation of a VX2 tumor model has traditionally required a laparotomy and surgical implantation of tumor fragments. Open surgical procedures are invasive and require long procedure times and recovery that can result in post-operative morbidity and mortality. The purpose of this study is to report the results of a percutaneous ultrasound guided method for… (More)
We evaluated R1 curves, CNR and scar visualization and quantification in a dog model of myocardial infarction by CMR, using three different contrast agents: Gadopen-tate dimeglumine (Gd-DTPA, Magnevist), Gadobenate dimeglumine (Gd-BOPTA, MultiHance), and Gadofos-veset (Ablavar). Gd-DTPA showed better characteristics for myocardial scar visualization and… (More)
A direct, high-resolution measurement from lunar orbit of the location of high concentrations of 3 He in the lunar regolith is needed for the initiation of cost-effective mining operations on the moon. Gamma-ray spectroscopy has been successfully used to map the abundances and distributions of certain elements present in planetary regoliths. Helium-3 is… (More)
Of 275 renal transplants performed over seven years in a single unit, azathioprine was the main immunosuppressive agent in 128 and cyclosporin in 147. With azathioprine graft survival was, as expected, negatively related to the number of HLA mismatches; with cyclosporin the reverse held true.