Daniel Šaňák, David Horák
Although the computed tomography (CT) is still considered to be a gold standard of brain imaging before thrombolysis, new reperfusion strategies in acute ischemic stroke evoked the use of magnetic resonance imaging (MRI). MRI allows accurate diagnostic of infarct lesion, detection of cerebral arterial occlusion or significant stenosis with evaluation of actual collateral flow and may display also certain reversible ischemic changes. MRI can also exclude reliably intracranial haemorrhage. The PWI/DWI mismatch concept as a result of effort to extend strict therapeutic time window was established to identify the presence of ischemic penumbra. Nevertheless non-standard methodology, analysis and different interpretations are still significant limitations for routine clinical practice.