What is the use of MRI for in-hospital stroke evaluation?
The use of MRI for in-hospital stroke evaluation grew dramatically from 1999 to 2008, varying widely. The growth was likely related to wide-spread appreciation of the diagnostic yield of follow-up brain imaging with MRI within 1 to 2 days. About one-quarter of acute stroke cases with an initially negative head CT will have an MRI with evidence of acute ischemic stroke. For posterior circulation strokes in particular, a follow-up MRI may be appropriate to confirm a diagnosis even when the initial MRI is negative. MRI with diffusion-weighted imaging is also particularly helpful in evaluating patients with low-risk TIA and mild neurological symptoms. Confirming the diagnosis of acute ischemic stroke with brain imaging may help with patient education and prognostication, which in turn may promote adherence to a prescribed prevention regimen.