Details

Autor(en) / Beteiligte

• Robertson, Craig A
• McCabe, Christopher
• Gallagher, Lindsay
• del Rosario Lopez-Gonzalez, Maria
• Holmes, William M
• Condon, Barrie
• Muir, Keith W
• Santosh, Celestine
• Macrae, I Mhairi

Titel

Stroke penumbra defined by an MRI-based oxygen challenge technique: 1. Validation using [ C]2-deoxyglucose autoradiography

Ist Teil von

• Journal of cerebral blood flow and metabolism, 2011-08, Vol.31 (8), p.1778-1787

Ort / Verlag

London, England: SAGE Publications

Erscheinungsjahr

2011

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• Accurate identification of ischemic penumbra will improve stroke patient selection for reperfusion therapies and clinical trials. Current magnetic resonance imaging (MRI) techniques have limitations and lack validation. Oxygen challenge T*2 MRI (T*2 OC) uses oxygen as a biotracer to detect tissue metabolism, with penumbra displaying the greatest T*2 signal change during OC. [14C]2-deoxyglucose (2-DG) autoradiography was combined with T*2 OC to determine metabolic status of T*2-defined penumbra. Permanent middle cerebral artery occlusion was induced in anesthetized male Sprague-Dawley rats (n = 6). Ischemic injury and perfusion deficit were determined by diffusion- and perfusion-weighted imaging, respectively. At 147 ± 32 minutes after stroke, T*2 signal change was measured during a 5-minute 100% OC, immediately followed by 125 μCi/kg 2-DG, intravenously. Magnetic resonance images were coregistered with the corresponding autoradiograms. Regions of interest were located within ischemic core, T*2-defined penumbra, equivalent contralateral structures, and a region of hyperglycolysis. A T*2 signal increase of 9.22% ± 3.9% (mean ± s.d.) was recorded in presumed penumbra, which displayed local cerebral glucose utilization values equivalent to contralateral cortex. T*2 signal change was negligible in ischemic core, 3.2% ± 0.78% in contralateral regions, and 1.41% ± 0.62% in hyperglycolytic tissue, located outside OC-defined penumbra and within the diffusion abnormality. The results support the utility of OC-MRI to detect viable penumbral tissue following stroke.