Blood Oxygen Level-Dependent MR Imaging of the Kidneys

Can Blood Oxygen Level-Dependent Imaging Depict the Ischemic Penumbra?

Regional dynamic signal changes during controlled hyperventilation assessed with blood oxygen level-dependent functional MR imaging.

PURPOSE To quantitate the amplitude changes and temporal dynamics of regional functional MR imaging signals during voluntary hyperventilation using blood oxygen level-dependent contrast echo-planar imaging. METHODS Seven male subjects were studied during voluntary hyperventilation (PetCO2 = 20 mm Hg) regulated by capnometry. Measurements were made on multisection echo-planar MR images obtaine...

Oxygen imaging by MRI: can blood oxygen level-dependent imaging depict the ischemic penumbra?

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...

The effect of prior surgery on blood oxygen level-dependent functional MR imaging in the preoperative assessment of brain tumors.

BACKGROUND AND PURPOSE Blood oxygen level-dependent functional MR imaging (BOLD fMRI) is a clinically useful technique for preoperative mapping of eloquent cortices in patients with brain tumors. The purpose of this study was to determine the effect on BOLD fMRI accuracy of susceptibility artifacts caused by prior surgery by comparing volumes of activation in the primary motor cortex (PMC) of p...

Application of sensitivity-encoded echo-planar imaging for blood oxygen level-dependent functional brain imaging.

The benefits of sensitivity-encoded (SENSE) echo-planar imaging (EPI) for functional MRI (fMRI) based on blood oxygen level-dependent (BOLD) contrast were quantitatively investigated at 1.5 T. For experiments with 3.4 x 3.4 x 4.0 mm(3) resolution, SENSE allowed the single-shot EPI image acquisition duration to be shortened from 24.1 to 12.4 ms, resulting in a reduced sensitivity to geometric di...