Also, neuroimaging, usually MRI, should be done if patients have any of the following: Focal neurologic deficit of subacute or uncertain onset New onset Age > 50 years Cancer HIV infection or AIDS Change in an established headache pattern Diplopia In addition, if meningitis, subarachnoid hemorrhage, encephalitis, or any cause of meningismus is being considered, lumbar puncture and cerebrospinal fluid (CSF) analysis should be done, if not contraindicated by imaging results.