Penumbra Detection using PWI/DWI Mismatch MRI in a Rat Stroke Model with and without Comorbidity: Comparison of Methods
Open Access
- 6 June 2012
- journal article
- research article
- Published by SAGE Publications in Journal of Cerebral Blood Flow & Metabolism
- Vol. 32 (9), 1765-1777
- https://doi.org/10.1038/jcbfm.2012.69
Abstract
Perfusion-diffusion (perfusion-weighted imaging (PWI)/diffusion-weighted imaging (DWI)) mismatch is used to identify penumbra in acute stroke. However, limitations in penumbra detection with mismatch are recognized, with a lack of consensus on thresholds, quantification and validation of mismatch. We determined perfusion and diffusion thresholds from final infarct in the clinically relevant spontaneously hypertensive stroke-prone (SHRSP) rat and its normotensive control strain, Wistar-Kyoto (WKY) and compared three methods for penumbra calculation. After permanent middle cerebral artery occlusion (MCAO) (WKY n=12, SHRSP n=15), diffusion-weighted (DWI) and perfusion-weighted (PWI) images were obtained for 4 hours post stroke and final infarct determined at 24 hours on T2 scans. The PWI/DWI mismatch was calculated from volumetric assessment (perfusion deficit volume minus apparent diffusion coefficient (ADC)-defined lesion volume) or spatial assessment of mismatch area on each coronal slice. The ADC-derived lesion growth provided the third, retrospective measure of penumbra. At 1 hour after MCAO, volumetric mismatch detected smaller volumes of penumbra in both strains (SHRSP: 31±50 mm3, WKY: 22±59 mm3, mean±s.d.) compared with spatial assessment (SHRSP: 36±15 mm3, WKY: 43±43 mm3) and ADC lesion expansion (SHRSP: 41±45 mm3, WKY: 65±41 mm3), although these differences were not statistically significant. Spatial assessment appears most informative, using both diffusion and perfusion data, eliminating the influence of negative mismatch and allowing the anatomical location of penumbra to be assessed at given time points after stroke.Keywords
This publication has 41 references indexed in Scilit:
- Impact of Genetic and Renovascular Chronic Arterial Hypertension on the Acute Spatiotemporal Evolution of the Ischemic Penumbra: A Sequential Study with MRI in the RatJournal of Cerebral Blood Flow & Metabolism, 2010
- Quantitative Temporal Profiles of Penumbra and Infarction During Permanent Middle Cerebral Artery Occlusion in RatsTranslational Stroke Research, 2010
- Differences in the Evolution of the Ischemic Penumbra in Stroke-Prone Spontaneously Hypertensive and Wistar-Kyoto RatsStroke, 2009
- Cerebral Blood Flow Threshold of Ischemic Penumbra and Infarct Core in Acute Ischemic StrokeStroke, 2006
- Impaired Functional Recovery After Stroke in the Stroke-Prone Spontaneously Hypertensive RatStroke, 2005
- Increased Reactive Oxygen Species in Rostral Ventrolateral Medulla Contribute to Neural Mechanisms of Hypertension in Stroke-Prone Spontaneously Hypertensive RatsCirculation, 2004
- Spreading of Vasogenic Edema and Cytotoxic Edema Assessed by Quantitative Diffusion and T2 Magnetic Resonance ImagingStroke, 1997
- Reversible focal ischemic injury demonstrated by diffusion-weighted magnetic resonance imaging in rats.Stroke, 1992
- Differential outcome to middle cerebral artery occlusion in spontaneously hypertensive stroke-prone rats (SHRSP) and Wistar Kyoto (WKY) rats.Stroke, 1983
- Cerebrovascular permeability following MCA occlusion in the ratJournal of Neurosurgery, 1982