Acute Stroke Diagnosis.

Stroke accounts for significant morbidity and mortality and is the fifth leading cause of death in the United States, with direct and indirect costs of more than $100 billion annually. Expedient recognition of acute neurologic deficits with appropriate history, physical examination, and glucose testing will help diagnose stroke and rule out mimicking presentations. The National Institutes of Health Stroke Scale should be used to determine stroke severity and to monitor for evolving changes in clinical presentation. Initial neuroimaging is used to differentiate between ischemic and hemorrhagic stroke or other pathologic processes. If a stroke is determined to be ischemic within four and a half hours of last known well or baseline state, determining the patient's eligibility for the administration of intravenous recombinant tissue plasminogen activator is necessary to proceed with informed decision-making for diagnostic workup and appropriate treatment options. Additional evaluation with specialized magnetic resonance imaging studies can help determine if patients can receive recombinant tissue plasminogen activator within nine hours of last known well. Subarachnoid hemorrhage should be considered in the differential diagnosis if the patient presents with rapid onset of severe headache. If radiographic imaging is negative for hemorrhage when there is high suspicion for delayed presentation of stroke, a lumbar puncture should be considered for further evaluation. Patients with cerebellar symptoms should be evaluated with a HINTS (head-impulse, nystagmus, test of skew) examination because it is more sensitive for cerebellar stroke than early magnetic resonance imaging. Additional cerebrovascular imaging should be considered in patients with large vessel occlusions presenting within 24 hours of last known well to assess benefits of endovascular interventions. Once initial interventions have been implemented, poststroke evaluations such as telemetry, echocardiography, and carotid imaging should be performed as clinically indicated to determine the etiology of the stroke.