Reduction of diffusion-weighted MRI lesion volume after early moderate hypothermia in ischemic stroke.

BACKGROUND Large areas of restricted diffusion in the middle cerebral artery (MCA) territory are highly predictive of severe and potentially space-occupying MCA stroke. A reduction of diffusion-weighted MRI (DWI) lesions occurs in 20% to 40% of acute stroke patients with early reperfusion. METHODS We report of a patient with a severe stroke syndrome who was treated with early moderate hypothermia but not thrombolysis. RESULTS The initially large DWI deficit of the whole MCA territory contrasted to the relatively small final lesion restricted to the basal ganglia on MRI and computed tomography scan. CONCLUSIONS This case describes an unexpected reduction of a DWI lesion after early moderate hypothermia and spontaneous recanalization 3 days after stroke onset. We discuss potential reasons for the unexpected DWI lesion reduction.