BackgroundUp to 25% of stroke patients wake up with a neurological deficit, so called wake-up stroke (WUS). Different imaging approaches that may aid in the selection of patients likely to benefit from reperfusion therapy are currently under investigation. The magnetic resonance imaging (MRI) diffusion weighted imaging – fluid attenuated inversion recovery (DWI-FLAIR) mismatch concept is one proposed method for identifying patients presenting within 4.5 hours of the ischemic event.PurposeTo report our experience with the DWI-FLAIR mismatch concept for selection of wake-up stroke patients to be thrombolysed at our centre.Material and methodsPatients treated with off label intravenous thrombolysis (IVT) for WUS at our centre during a 6.5-month period were included. We performed MRI including DWI and FLAIR in all patients at admission. Each MRI examination was rated as either DWI-FLAIR mismatch or match. National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale were used to measure clinical outcome. Cerebral computed tomography (CT) or MRI was performed within 24 hours after thrombolysis to determine the presence of any intracranial haemorrhage (ICH).ResultsTen patients treated with IVT for WUS were included. Four patients had a DWI-FLAIR mismatch and after IVT treatment the mean reduction in NIHSS in the DWI-FLAIR mismatch group was 4.0. In the DWI-FLAIR match group the mean reduction in NIHSS after IVT therapy was 4.8. None of the ten patients had any signs of ICH on follow-up imaging.ConclusionsIn this small series DWI-FLAIR mismatch was not associated with worse outcome or ICH. This suggests that selecting WUS patients using DWI-FLAIR mismatch in clinical trials may exclude a large group of patients who might benefit.

Manual segmentation of HGG is very time-consuming and using the SAM could increase the efficiency of this process. However, the accuracy of the SAM ultimately depends on the expert doing the editing. Our study confirmed a considerable inter-observer variability among experts defining tumor volume from volumetric MRIs.

Patients who suffer acute ischaemic stroke can be treated with thrombolysis if therapy is initiated early. Radiological evaluation of the intracranial tissue before such therapy can be given is mandatory. In this review current radiological diagnostic strategies are discussed for this patient group. Beyond non-enhanced computed tomography (CT), the standard imaging method for many years, more sophisticated CT stroke protocols including CT angiography and CT perfusion have been developed, and additionally an increasing number of patients are examined with magnetic resonance imaging as the first imaging method used. Advantages and challenges of the different methods are discussed.