Neuroimaging in acute ischaemic stroke: insights into unanswered questions of pathophysiology
Article first published online: 25 NOV 2009
© 2010 Blackwell Publishing Ltd
Journal of Internal Medicine
Volume 267, Issue 2, pages 172–190, February 2010
How to Cite
Wardlaw, J. M. (2010), Neuroimaging in acute ischaemic stroke: insights into unanswered questions of pathophysiology. Journal of Internal Medicine, 267: 172–190. doi: 10.1111/j.1365-2796.2009.02200.x
- Issue published online: 19 JAN 2010
- Article first published online: 25 NOV 2009
- ischaemic penumbra;
Wardlaw JM (Western General Hospital, Edinburgh, UK). Neuroimaging in acute ischaemic stroke: insights into unanswered questions of pathophysiology (Review). J Intern Med 2010; 267: 172–190.
Abstract. The treatment of acute ischaemic stroke is based on the principle that there is ischaemic but still potentially salvageable tissue that could be rescued if blood flow could be restored quickly. It is assumed that salvage might only be possible in the first few hours, and that infarct expansion is a direct result of failed recanalization of the main artery. This concept arose from experimental work in the 1970s, supported more recently by studies using imaging to identify penumbral tissue. However, although magnetic resonance diffusion and perfusion imaging is a way of imaging penumbral tissue and has been around for over a decade, it is not an easy technique to apply in practice and its use has produced conflicting results. Computed tomography perfusion, and any other tissue perfusion imaging technique, is likely to encounter the same difficulties. Indeed many factors, other than the presence of a diffusion-perfusion mismatch acutely, may determine or influence ultimate tissue fate even days after the stroke, and in turn, clinical outcome. Many of these potential influences are beginning to emerge from studies using different forms of imaging at later times after stroke. This review will explore the information now emerging from imaging studies in large artery ischaemic stroke to summarize knowledge to date and indicate unresolved issues for the future.