Introduction: Patients with transient neurologic symptoms are usually assessed based on physicians’ assumptions; these patients are usually diagnosed with transient ischemic attack (TIA). This study investigated the yield of multimodality magnetic resonance (MRI) for differentiating the TIA from TIA mimics. 
Objective: This retrospective study consecutively identified patients who arrived at the emergency department with transient or rapidly improving symptoms within 12 h of symptom onset between July 2015 and December 2016. They conducted the multimodality MRI composed of diffusion weighted imaging (DWI) and non-contrast and contrast fluid-attenuated inversion recovery (FLAIR) images with gradient-recalled echo imaging, time-of-flight MR angiography, and dynamic susceptibility perfusion-weighted imaging (PWI). The DWI lesion and Hyperintense acute reperfusion marker (HARM) on FLAIR images were determined. The association of final diagnosis confirmed at discharge was analyzed by the DWI lesion and HARM signs.
Results: A total of 174 subjects were enrolled (mean age, 64.0 ± 12.9 years old; male, 54.6%). The DWI lesion was observed in 17.8% whose final diagnosis was TIA. HARM sign was observed in 18 (10%) patients, and their final diagnoses were classified as true TIA (n = 11), seizure (n = 2), posterior reversible encephalopathy (n = 2), reversible cerebral vascular constriction (n = 1) and unclassified encephalopathy (n = 2). The co-incidence of DWI lesion and HAMM signs were observed in 6 subjects who showed the symptomatic steno-occlusive lesions in MCA and ICA. 
Conclusion: The investigation of HARM would be helpful in order to make exact diagnoses in patients suspected of having TIA.

The role of multimodality MR Imaging in patients with transient ischemic attack