Steven K. White

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BACKGROUND Aortic stenosis (AS) leads to diffuse fibrosis in the myocardium, which is linked to adverse outcome. Myocardial T1 values change with tissue composition. OBJECTIVE To test the hypothesis that our recently developed non-contrast cardiac magnetic resonance (CMR) T1 mapping sequence could identify myocardial fibrosis without contrast agent. (More)
BACKGROUND Myocardial extracellular volume (ECV) is elevated in fibrosis or infiltration and can be quantified by measuring the haematocrit with pre and post contrast T1 at sufficient contrast equilibrium. Equilibrium CMR (EQ-CMR), using a bolus-infusion protocol, has been shown to provide robust measurements of ECV using a multibreath-hold T1 pulse(More)
We have constructed a high-efficiency expression vector to direct the synthesis of heterologous polypeptides in yeast. The vector is termed a sandwich expression vector as the heterologous gene is inserted between the 5' and 3' control regions of the efficiently expressed yeast PGK gene. We have used this vector to direct the expression of three derivatives(More)
BACKGROUND Anderson-Fabry disease (AFD) is a rare but underdiagnosed intracellular lipid disorder that can cause left ventricular hypertrophy (LVH). Lipid is known to shorten the magnetic resonance imaging parameter T1. We hypothesized that noncontrast T1 mapping by cardiovascular magnetic resonance would provide a novel and useful measure in this disease(More)
OBJECTIVES The aim of this study was to determine the accuracy of the contrast "bolus only" T1 mapping cardiac magnetic resonance (CMR) technique for measuring myocardial extracellular volume fraction (ECV). BACKGROUND Myocardial ECV can be measured with T1 mapping before and after contrast agent if the contrast agent distribution between blood/myocardium(More)
BACKGROUND There is little data on the burden or causes of epilepsy in developing countries, particularly in children living in sub-Saharan Africa. METHODS We conducted two surveys to estimate the prevalence, incidence and risk factors of epilepsy in children in a rural district of Kenya. All children born between 1991 and 1995 were screened with a(More)
OBJECTIVES The authors sought to generate a synthetic extracellular volume fraction (ECV) from the relationship between hematocrit and longitudinal relaxation rate of blood. BACKGROUND ECV quantification by cardiac magnetic resonance (CMR) measures diagnostically and prognostically relevant changes in the extracellular space. Current methodologies require(More)
OBJECTIVE To measure and assess the significance of myocardial extracellular volume (ECV), determined non-invasively by equilibrium contrast cardiovascular magnetic resonance, as a clinical biomarker in health and a number of cardiac diseases of varying pathophysiology. DESIGN Prospective study. SETTING Tertiary referral cardiology centre in London, UK.(More)
PURPOSE Multiple, prolonged, generalized, or focal seizures are common in children with severe malaria, with or without coma. In other contexts, such seizures have been associated with the development of epilepsy. The relation between falciparum malaria and epilepsy is undetermined; thus we measured the prevalence and characteristics of epilepsy in children(More)
PURPOSE To explore the use and reproducibility of magnetic resonance-derived myocardial T1 mapping in patients with iron overload. MATERIALS AND METHODS The research received ethics committee approval and all patients provided written informed consent. This was a prospective study of 88 patients and 67 healthy volunteers. Thirty-five patients underwent(More)