Is CT Scan in Patients with Suspected TIA Necessary: A quality improvement initiative (P2.307)

OBJECTIVE: To evaluate utility of using magnetic resonance imaging (MRI) only rather than computed tomography (CT) plus MRI in evaluation of transient ischemic attack (TIA) patients. BACKGROUND: TIA is a neurologic emergency. Current guidelines recommend neuroimaging favoring MRI with diffusion sequence to best evaluate for acute ischemia. Often times CT is performed as initial evaluation, before obtaining MRI. DESIGN/METHODS: Adults with suspected TIA were placed in our emergency department (ED) Clinical Decision Unit (CDU) protocol for evaluation. We reviewed consecutive cases from November 2013 to August 2014. Initial review of the patients in March 2014 showed most patients received both CT and MRI imaging. We revised the protocol in April 2014 to favor only MRI in patients who were felt to be at low risk for intracranial hemorrhage. Diagnostic test utilization, presence of headache, seizure, HTN, focal neurologic symptoms, anticoagulant therapy and presence of stroke were analyzed in all patients before and after this change in protocol. RESULTS: We identified 218 patients who were observed under TIA protocol, 150 of whom (68.8[percnt]) received both CT and MRI. Fifty one patients (24[percnt]) had MRI only and 17 (7.8[percnt]) had CT only. Prior to the protocol change, only 8 patients (7.8[percnt]) had MRI alone, whereas after the change, 43 patients (37.1[percnt]) had MRI only (p<0.0001). No patients in either group had underlying intracranial hemorrhage. There were no differences in those with or without headache, HTN, neurologic symptoms, or anticoagulation who received MRI only. There were 36 (16.5[percnt]) patients with stroke identified by imaging. CONCLUSIONS: Patients with suspected TIA and low risk for intracranial hemorrhage could undergo MRI rather than CT plus MRI. This practice would prevent unnecessary radiation dose from CT, decrease cost, and increase availability of the CT scanner for other patients in the ED. Disclosure: Dr. Baghshomali has nothing to disclose. Dr. Bishop has nothing to disclose. Dr. Hiestand has nothing to disclose. Dr. Reynolds has nothing to disclose. Dr. Bushnell has nothing to disclose.