BACKGROUND AND PURPOSE Blood oxygen level-dependent MRI (BOLD MRI) of hypercapnia-induced changes in cerebral blood flow is an emerging technique for mapping cerebrovascular reactivity (CVR). BOLD MRI signal reflects cerebral blood flow, but also depends on cerebral blood volume, cerebral metabolic rate, arterial oxygenation, and hematocrit. The purpose of this study was to determine whether, i...

Introduction: Tumor oxygenation plays an important role in malignant progression, metastasis and response to various therapies. F MR oximetry based on the reporter molecule hexafluorobenzene (HFB) using the FREDOM (Fluorocarbon Relaxometry using Echo planar imaging for Dynamic Oxygen Mapping) approach offers quantitative measurements of pO2 with spatial and temporal resolution allowing the dyna...

The spatial distributions of functional activation of rat somatosensory cortex by forepaw stimulation were quantitatively compared using blood oxygen level dependent (BOLD) signal and signal weighted by cerebral blood volume (CBV). The BOLD contrast to noise (CNR) distribution showed a significant dorsal shift with respect to the CBV method at fields strengths of 2 T (0.69 +/- 0.09 mm) and 4.7 ...

Introduction The BOLD-contrast mechanism arises from the change of blood oxygenation during cortical activation as a consequence of the increased arterial blood supply, which is most likely due to the increased oxygen demand. It has been originally suggested for the observation of neuronal activation (1). Recently it could be demonstrated, that changes in blood oxygen level can also be used for...

Well-regulated blood flow within the brain is vital to normal function. The brain's requirement for sufficient blood flow is ensured by a tight link between neural activity and blood flow. The link between regional synaptic activity and regional cerebral blood flow, termed functional hyperemia, is the basis for several modern imaging techniques that have revolutionized the study of human brain ...

Background Coronary artery disease (CAD) and left ventricular hypertrophy are prevalent in the chronic kidney disease (CKD) and renal transplant population. Advances in cardiovascular magnetic resonance (CMR) with the blood oxygen level-dependent (BOLD) technique provides unprecedented capability to assess myocardial oxygenation as a measure of ischaemia. We hypothesised that myocardial oxygena...

A large-scale brain network can be defined as a set of segregated and integrated regions, that is, distant regions that share strong anatomical connections and functional interactions. Data-driven investigation of such networks has recently received a great deal of attention in blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI). We here review the rationale for suc...

M apping the ischemic penumbra (ie, the neurophysio-logically silent but still viable ischemic tissue) is increasingly part of routine assessment in suspected acute stroke, although whether this approach is cost-effective is still unclear. 1,2 The penumbra is characterized by both low cerebral blood flow (CBF; Ͻ20 mL ⅐ 100 g Ϫ1 ⅐ min Ϫ1) and elevated oxygen extraction fraction (OEF). 3 The latt...

Myocardial perfusion and wall motion assessment by CMR for detection of CAD. Contrast media (CM) first-pass techniques are the most commonly used approaches for perfusion-CMR. Alternatively, blood oxygen level dependent (BOLD) techniques and spin-labeling techniques have also been applied to measure myocardial perfusion, but are still in an early experimental stage. As an alternative for perfus...

Background By exploiting the paramagnetic properties of deoxyhemoglobin, blood oxygen level-dependent (BOLD) MRI can detect myocardial ischemia in patients with coronary artery disease. However, little is known about myocardial tissue oxygenation in pathological left ventricular hypertrophy (e.g. HCM) or physiological hypertrophy (e. g. elite athletes). Perfusion studies have shown that patient...