Learn More
Packed erythrocytes are ideally suited as a model system for the study of water diffusion in biological tissue, because cell size, membrane permeability, and extracellular volume fraction can be varied independently. We used a pulsed-field-gradient spin echo NMR technique to measure the time-dependent diffusion coefficient D(t) in packed erythrocytes. The(More)
Traumatic brain injury (TBI) is increasingly appreciated to be highly prevalent and deleterious to neurological function. At present, no effective treatment options are available, and little is known about the complex cellular response to TBI during its acute phase. To gain insights into TBI pathogenesis, we developed a novel murine closed-skull brain(More)
Loss of integrity of the blood-brain barrier (BBB) resulting from ischemia and reperfusion is a hypothesized precursor to hemorrhagic transformation (HT) and worse clinical outcome than would be expected from the beneficial effects of reperfusion. We used a novel magnetic resonance imaging marker to characterize early BBB disruption in acute focal brain(More)
Radiologic brain imaging is the most useful means of visualizing and categorizing the location, nature, and degree of damage to the central nervous system sustained by patients with traumatic brain injury (TBI). In addition to determining acute patient management and prognosis, imaging is crucial for the characterization and classification of injuries for(More)
The measurement of the apparent diffusion coefficient (ADC) of water in brains of stroke patients is used in models developed to help distinguish reversible from irreversible ischemic injury. The ADC by conventional methods may be overestimated by the presence of cerebral spinal fluid (CSF) in sulci and perivascular spaces. In this study the hypothesis that(More)
BACKGROUND AND PURPOSE Analogous to the CT hyperattenuated vessel sign (HMCAS), MR imaging may show hypo- or hyperintense vessels in acute ischemic stroke (AIS) patients. We assessed the diagnostic and prognostic strength of early MR imaging vessel signs in AIS patients treated with intravenous thrombolysis (IVT) within 3 hours of the onset of symptoms. (More)
BACKGROUND Although the use of magnetic resonance imaging (MRI) for the diagnosis of acute stroke is increasing, this method has not proved more effective than computed tomography (CT) in the emergency setting. We aimed to prospectively compare CT and MRI for emergency diagnosis of acute stroke. METHODS We did a single-centre, prospective, blind(More)
BACKGROUND Hyperintense vessels (HV) on fluid-attenuated inversion recovery imaging are frequently observed in acute ischemic stroke patients. However, the exact mechanism and clinical implications of this sign have not yet been clearly defined. The features of HV and its relevance to other imaging factors are presented here. METHODS Prominence and(More)
A method is demonstrated for the noninvasive detection and study of spreading cortical depression. Spreading depression (SD) was elicited in rats by topical application of potassium chloride to the exposed cortex. The apparent diffusion coefficient (Dapp) of water in a region of the cortex, measured using a PFG-NMR spin echo sequence with an observation(More)