Abstract P298: Redundant Imaging in TIA: Evidence From the Nationwide Emergency Department Sample (NEDS)

Introduction: Multiple societal guidelines recommend patients with TIA be emergently imaged with brain-MRI and neurovascular screening-CTA, MRA or carotid ultrasound-to identify and treat risk factors for future stroke. Increased ED compliance with TIA imaging guidelines has previously been demonstrated, along with a substantial increase in imaging utilization over the past decade. The purpose of this study was to quantify prevalence of redundant imaging during ED work-up of TIA, and to identify imaging practices that could be targeted to reduce unnecessary expenditures. Methods: Utilizing the 2006-2017 Nationwide Emergency Department Sample, patients discharged with TIA from EDs in the US were identified using ICD-9/10 codes. Brain and neurovascular imaging obtained during the encounter was identified using CPT codes. Demographics, payor, patient income, and hospital characteristics were incorporated into a hierarchical multivariable logistic regression analysis to identify significant associations with redundant neuroimaging. Results: In 2017 there were 184,870 patients discharged from EDs with TIA. Redundant brain, brain vascular, and cervical vascular imaging was identified in 55,513(30%), 5,149(2.8%) and 1,325(0.7%) of encounters respectively. Decreased odds of obtaining redundant neuroimaging in a TIA encounter was observed in Medicaid patients(OR:0.72, 95%CI:0.64-0.81), non-trauma centers(OR:0.49, 95%CI:0.26-0.93), rural hospital locations(OR:0.18, 95%CI:0.11-0.29) and weekend encounters(OR:0.9, 95%CI:0.85-0.96). Trend analysis from 2006 to 2017 demonstrated a rise in redundant brain and neurovascular imaging from 2.3% and 0.2% of encounters respectively in 2006 to 30% and 3.5% of encounters in 2017. Using Medicare fee estimates, in 2017 redundant brain and neurovascular imaging for patients discharged from EDs with TIA resulted in additional charges of approximately 8,670,832 USD. Conclusion: Increasing utilization of imaging for workup of TIA across EDs in the US is also associated with substantial and increasing use of redundant imaging. We identify redundant brain and neurovascular imaging as areas that could be targeted to mitigate rising imaging expenditures.