Penumbral mismatch is underestimated using standard volumetric methods and this is exacerbated with time.
J Neurol Neurosurg Psychiatry
; 80(9): 991-6, 2009 Sep.
Article
em En
| MEDLINE
| ID: mdl-19357125
ABSTRACT
BACKGROUND AND AIMS:
The mismatch between perfusion weighted images (PWI) and diffusion weighted images (DWI) using MR is increasingly being applied in patient selection for therapeutic trials. Two approaches to the calculation of the mismatch volume exist--the commonly used volumetric and the more precise co-registration method, the latter of which considers lesion topography. That there are differences in the mismatch volume analysed by each method and that these are time dependent was hypothesised.METHODS:
Patients within 48 h of ischaemic stroke onset had baseline MR PWI/DWI mismatch and T2 outcome volumes at 3 months. Volumetric mismatch volume was defined as PWI minus DWI lesion. Co-registration mismatch volume was defined as the PWI defect lesion not overlapped by the co-registered DWI lesion.RESULTS:
72 patients of median age 74.0 years were studied. Median baseline MR was at 5.9 h (IQR 3.0, 20.4 h) after stroke onset. Consistent underestimation of the mismatch volume occurred using the volumetric method (volumetric median 9.3 ml, IQR 0, 63 ml; co-registration median 20.1 ml, IQR 3.2, 69.8 ml; p<0.0001). This difference increased with time from stroke onset (p = 0.006).CONCLUSIONS:
Volumetric analysis consistently underestimates the PWI/DWI mismatch volume compared with the more precise co-registration method. This effect increases with time.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Imageamento por Ressonância Magnética
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Acidente Vascular Cerebral
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Imagem de Difusão por Ressonância Magnética
Tipo de estudo:
Diagnostic_studies
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Etiology_studies
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Incidence_studies
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Observational_studies
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Risk_factors_studies
Limite:
Adult
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Aged
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Aged80
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
J Neurol Neurosurg Psychiatry
Ano de publicação:
2009
Tipo de documento:
Article
País de afiliação:
Austrália