Abstract | BACKGROUND AND PURPOSE: The timing and mechanisms of protection by hyperbaric oxygen (HBO) in cerebral ischemia have only been partially elucidated. We monitored the early in vivo effects of HBO after 2 h transient focal ischemia using repetitive MRI. METHODS: Wistar rats underwent filament occlusion of the middle cerebral artery (MCAO). 40 min after MCAO, rats were placed in a HBO chamber and breathed either 100% O(2) at 3.0 atmospheres absolute (ata; n = 24) or at 1.0 ata (control; n = 24) for 1 h. Diffusion, perfusion and T2-weighted MR-images were obtained after 15 min and 3, 6 and 24 h of reperfusion. In 6 axial MR slices, volume of abnormal diffusion and T2w signals were measured in the ischemic hemisphere. Furthermore, hemispheric mean apparent diffusion coefficient- (ADC) and T2 values were calculated for statistical analysis. RESULTS: HBO significantly reduced volume of abnormal DWI signal beginning immediately after reperfusion (control: 92 +/- 28 mm(3); HBO: 64 +/- 17) and lesion size on T2w (control: 375 +/- 91 mm(3); HBO: 225 +/- 39) after 24 h. Correspondingly, mean ADC levels were lower and T2 values higher in the ischemic hemisphere in the control group. HBO reduced histological infarct size at 24 h. CONCLUSION: High-dose intraischemic HBO therapy has an immediate protective on the brain which is superior to normobaric oxygen.
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Authors | Roland Veltkamp, Dirk A Siebing, Sabine Heiland, Philip Schoenffeldt-Varas, Claudia Veltkamp, Markus Schwaninger, Stefan Schwab |
Journal | Brain research
(Brain Res)
Vol. 1037
Issue 1-2
Pg. 134-8
(Mar 10 2005)
ISSN: 0006-8993 [Print] Netherlands |
PMID | 15777761
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Topics |
- Animals
- Functional Laterality
(physiology)
- Hyperbaric Oxygenation
- Infarction, Middle Cerebral Artery
(pathology)
- Ischemic Attack, Transient
(pathology, prevention & control)
- Magnetic Resonance Imaging
- Male
- Rats
- Rats, Wistar
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