A systematic review in 2012 found no evidence that multimodal MRI when used purely for diagnostic purposes improves outcomes, although there was limited evidence that it can change management.61 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 An emergency depart- ment series of 252 patients presenting with atypical stroke symptoms and a negative CT found that 29 patients (11.5%) had acute ischemic stroke on MRI For posterior circulation strokes in particular, a follow-up MRI may be appro- priate to confirm a diagnosis even when the initial MRI is negative.64 MRI with diffusion-weighted imag- ing is also particularly helpful in evaluating patients with low-risk TIA and mild neurological symptoms.85 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.65 9. 