Diffusion-weighted imaging in acute stroke--a tool of uncertain value?
The concept of a mismatch between the lesion volume in diffusion- and perfusion-weighted magnetic resonance imaging (MRI) indicating 'tissue at risk of infarction' is based on the assumption that tissue with diffusion slowing in diffusion-weighted MRI (DWI) or decreased values of the apparent diffusion coefficient represents irreversibly damaged tissue. Recent experimental as well as clinical studies, however, have shown that tissue with diffusion slowing may well normalize if the hypoperfusion is moderate or transient. We will interpret these findings in the light of experimental data and suggest a way for the interpretation of different time courses of lesion development in DWI within a clinical MRI protocol. MR stroke imaging delivers important information in acute stroke, particularly in defining the 'tissue at risk of infarction'.
Fiehler
Jens
J
Department of Neuroradiology, University Hospitals of Hamburg-Eppendorf, Hamburg, Germany. fiehler@uke.uni-hamburg.de
Fiebach
Jochen B
JB
Gass
Achim
A
Hoehn
Mathias
M
Kucinski
Thomas
T
Neumann-Haefelin
Tobias
T
Schellinger
Peter D
PD
Siebler
Mario
M
Villringer
Arno
A
Röther
Joachim
J
D002545:Brain Ischemia / Q000175:diagnosis / Q000503:physiopathology; D002560:Cerebrovascular Circulation; D038524:Diffusion Magnetic Resonance Imaging / Q000592:standards*; D006801:Humans; D020521:Stroke / Q000175:diagnosis* / Q000503:physiopathology; D013997:Time Factors; D014022:Tissue Survival