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BACKGROUND Serial surveillance endomyocardial biopsies are performed in patients who have recently undergone heart transplantation in order to detect acute cardiac allograft rejection (ACAR) before symptoms occur, however the biopsy process is associated with a number of limitations. This study aimed to prospectively and longitudinally evaluate the(More)
BACKGROUND Extracellular matrix expansion is a key element of ventricular remodeling and a potential therapeutic target. Cardiovascular magnetic resonance (CMR) T1-mapping techniques are increasingly used to evaluate myocardial extracellular volume (ECV); however, the most widely applied methods are without histological validation. Our aim was to perform(More)
Magnetic resonance imaging has shown promise for evaluating tissue oxygenation. In this study differences in the tissue longitudinal relaxation rate (R(1)) and effective transverse relaxation rate (R(*)(2)), induced by inhalation of pure oxygen and carbogen, were evaluated in 10 healthy subjects. Significant reductions in R(1) were demonstrated following(More)
Assessment of perfusion and capillary permeability is important in both malignant and nonmalignant lung disease. Kinetic modeling of T(1)-weighted dynamic contrast-enhanced MRI (DCE-MRI) data may provide such an assessment. This study establishes the feasibility and interrelationship of kinetic modeling approaches designed to estimate microvascular(More)
Dynamic contrast-enhanced MRI (DCE-MRI) is frequently used to provide response biomarkers in clinical trials of novel cancer therapeutics but assessment of their physiological accuracy is difficult. DCE-CT provides an independent probe of similar pharmacokinetic processes and may be modeled in the same way as DCE-MRI to provide purportedly equivalent(More)
This work presents preliminary results on the development, characterisation, and use of a novel physical phantom designed as a simple mimic of tumour cellular structure, for diffusion-weighted magnetic resonance imaging (DW-MRI) applications. The phantom consists of a collection of roughly spherical, micron-sized core-shell polymer 'cells', providing a(More)
PURPOSE There is considerable interest in developing non-invasive methods of mapping tumor hypoxia. Changes in tissue oxygen concentration produce proportional changes in the magnetic resonance imaging (MRI) longitudinal relaxation rate (R(1)). This technique has been used previously to evaluate oxygen delivery to healthy tissues and is distinct from blood(More)
OBJECTIVE To develop a method to determine the distribution of articular cartilage in the hip and to evaluate the potential of the method in a study of normal weight-bearing effects in asymptomatic young volunteers. DESIGN Six volunteers were scanned after periods of standing and lying supine, using 3D gradient-echo magnetic resonance imaging (MRI). The(More)
Molecular oxygen has been previously shown to shorten longitudinal relaxation time (T1) in the spleen and renal cortex, but not in the liver or fat. In this study, the magnitude and temporal evolution of this effect were investigated. Medical air, oxygen, and carbogen (95% oxygen/5% CO2) were administered sequentially in 16 healthy volunteers. T1 maps were(More)
OBJECTIVES This study sought to evaluate the diagnostic performance of multiparametric cardiovascular magnetic resonance (CMR) for detecting cardiac allograft vasculopathy (CAV) using contemporary invasive epicardial artery and microvascular assessment techniques as reference standards, and to compare the performance of CMR with that of angiography. (More)