MRA/DWI mismatch

Lansberg MG, Thijs VN, Bammer R, OUvot JM, Marks MP, Wechsler LR, Kemp S, Albers GW. The mra-dwi mismatch identifies patients with stroke who are likely to benefit from reperfusion. Stroke. 2008 39 2491-2496... 

The sensitivities and specificities of MRA for detecting acnte proximal large vessel occlnsions range from 70 to 100% [53]. A 2008 study examining a subset of patients from the DEFUSE trial showed that MRA-DWI mismatch (DWI lesion less than 25 ccs, with a proximal vessel occlusion, or DWI lesion less... 

Fig. 3.11. Patient who received t-PA following MRI. PI, = quantitative MTT map. There is a distal Ml occlusion on MRA, but no obvious tissue at risk (no perfusion-diffusion mismatch). The baseline DWI lesion is quite large. Thrombolysis successfully achieves recanalization and reperfusion, but there is also haemorrhagic transformation apparent on day 3 imaging...

CTA or MRA. The volume of the DWI lesion is shown in black and the volume of the perfusion mismatch is shown in gray. The majority of patients with a DWI lesion volume of 70 mL or less (horizontal line) had a perfusion/diffusion mismatch of over 100% without correlation to the time of stroke onset... 

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