In vivo diffusion–perfusion magnetic resonance imaging of acute cerebral ischemia

1991 ◽  
Vol 69 (11) ◽  
pp. 1719-1725 ◽  
Author(s):  
John Kucharczyk ◽  
Jan Mintorovitch ◽  
Haleh Asgari ◽  
Mitsuharu Tsuura ◽  
Michael Moseley
Keyword(s):  
Cerebral Ischemia ◽  
Magnetic Resonance ◽  
Resonance Imaging ◽  
Mr Images ◽  
Ischemic Brain ◽  
Diffusion Weighted ◽  
Acute Cerebral Ischemia ◽  
Planar Images ◽  
Echo Planar

We compared the anatomic extent and severity of ischemic brain injury shown on diffusion-weighted magnetic resonance (MR) images, with cerebral tissue perfusion deficits demonstrated by a nonionic intravascular T2*-shortening magnetic susceptibility contrast agent used in conjunction with standard T2-weighted spin-echo and gradient-echo echo-planar images. Diffusion-weighted images displayed increased signal intensity in the vascular territory of the middle cerebral artery 25–40 min after permanent occlusion, whereas T2-weighted images without contrast were negative or equivocal for at least 2–3 h after stroke was induced. Contrast-enhanced T2-weighted and echo-planar images revealed perfusion deficits that were spatially closely related to the anatomic regions of ischemic tissue injury. These data indicate that diffusion-weighted MR images are very sensitive to early onset pathophysiologic changes induced by acute cerebral ischemia. Combined sequential diffusion–perfusion imaging enables noninvasive in vivo examination of the relationship between hypoperfusion and evolving ischemic brain injury.Key words: in vivo, diffusion, perfusion, acute cerebral ischemia, magnetic resonance imaging.

scholarly journals Diffusion-Weighted Magnetic Resonance Imaging of Acute Focal Cerebral Ischemia: Comparison of Signal Intensity with Changes in Brain Water and Na+,K+ -ATPase Activity

1994 ◽  
Vol 14 (2) ◽  
pp. 332-336 ◽  
Author(s):  
Jan Mintorovitch ◽  
G. Y. Yang ◽  
Hiroaki Shimizu ◽  
John Kucharczyk ◽  
Pak H. Chan ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Magnetic Resonance ◽  
Atpase Activity ◽  
Water Content ◽  
Signal Intensity ◽  
Focal Cerebral Ischemia ◽  
Mr Images ◽  
Diffusion Weighted ◽  
Acute Cerebral Ischemia ◽  
Brain Water

Diffusion-weighted magnetic resonance (MR) images from rats during acute cerebral ischemia induced by middle cerebral artery occlusion were analyzed for correspondence with changes in brain water, cation concentrations, and Na+,K+-ATPase activity measured in vitro after 30 or 60 min of ischemia. In the ischemic hemisphere, signal intensity was increased at 30 min (p < 0.05 vs contralateral hemisphere) and further increased at 60 min. Na+,K+-ATPase activity was 34% lower in ischemic cortex and 40% lower in ischemic basal ganglia after 30 min (p < 0.05), but water content and Na+ and K+ concentrations were not significantly different between hemispheres. After 60 min, water content and Na+ concentration were increased, and both Na+,K+-ATPase activity and K+ concentration were decreased in the ischemic hemisphere (p < 0.05). These findings are consistent with the hypothesis that the early onset of signal hyperintensity in diffusion-weighted MR images may reflect cellular edema associated with impaired membrane pump function. Early in vivo detection and localization of potentially reversible ischemic cerebral edema may have important research and clinical applications.

scholarly journals In Vivo Monitoring of Inflammation After Cardiac and Cerebral Ischemia by Fluorine Magnetic Resonance Imaging

Circulation ◽  
2008 ◽  
Vol 118 (2) ◽  
pp. 140-148 ◽  
Author(s):  
Ulrich Flögel ◽  
Zhaoping Ding ◽  
Hendrik Hardung ◽  
Sebastian Jander ◽  
Gaby Reichmann ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Cerebral Ischemia ◽  
Magnetic Resonance ◽  
Resonance Imaging ◽  
In Vivo Monitoring ◽  
Fluorine Magnetic Resonance Imaging

Does non-echo-planar diffusion-weighted magnetic resonance imaging have a role in assisting the clinical diagnosis of cholesteatoma in selected cases?

2018 ◽  
Vol 132 (3) ◽  
pp. 207-213 ◽  
Author(s):  
R Nash ◽  
R K Lingam ◽  
D Chandrasekharan ◽  
A Singh
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Imaging Technique ◽  
Single Shot ◽  
Resonance Imaging ◽  
Diffusion Weighted ◽  
Weighted Magnetic Resonance Imaging ◽  
Operative Findings ◽  
Clinical Records ◽  
Echo Planar

AbstractObjective:To determine the diagnostic performance of diffusion-weighted magnetic resonance imaging in the assessment of patients with suspected, but not clinically evident, cholesteatoma.Methods:A retrospective analysis of a prospectively collected database of non-echo-planar diffusion-weighted magnetic resonance imaging studies (using a half-Fourier single-shot turbo-spin echo sequence) was conducted. Clinical records were retrospectively reviewed to determine indications for imaging and operative findings. Seventy-eight investigations in 74 patients with suspected cholesteatoma aged 5.7–79.2 years (mean, 41.7 years) were identified. Operative confirmation was available in 44 ears. Diagnostic accuracy of the imaging technique was calculated using operative findings as a ‘gold standard’. Sensitivity of the investigation was examined via comparison with clinically evident cholesteatoma.Results:The accuracy of diffusion-weighted magnetic resonance imaging in assessment of suspected cholesteatoma was 63.6 per cent. The imaging technique was significantly less accurate in assessment of suspected cholesteatoma than clinically evident disease (p< 0.001).Conclusion:Computed tomography and diffusion-weighted magnetic resonance imaging may be complementary in assessment of suspected cholesteatoma, but should be used with caution, and clinical judgement is paramount.

Echo-planar magnetic resonance imaging of Gaviscon alginate rafts in-vivo

2002 ◽  
Vol 54 (10) ◽  
pp. 1351-1356 ◽  
Author(s):  
Luca Marciani ◽  
Sarah L. Little ◽  
Janice Snee ◽  
Nicholas S. Coleman ◽  
Damian J. Tyler ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Resonance Imaging ◽  
Echo Planar
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