According to the American Journal of Roentgenology, neuroimaging utilization in the emergency department (ED) increased substantially between 2007 and 2017, with the growth of head and neck CT angiography (CTA) outperforming other modalities. By far, unenhanced head CT remains the leading ED neuroimaging examination.

“The rapid growth of head and neck CTA observed in the fee-for-service Medicare population is also observed in the commercially insured and Medicare Advantage populations,” writes corresponding author Selin Merdan, PhD, from the department of industrial and systems engineering at the Georgia Institute of Technology in Atlanta.

Merdan and colleagues assessed annual ED utilization of head CT, head MR, head CTA, neck CTA, head MR angiography (MRA), neck MRA, and carotid duplex ultrasound using anonymized patient-level claims from the Clinformatics Data Mart (Optum) for 2007–2017. Annually, this database includes 12 million to 14 million commercial and Medicare Advantage health plan enrollees. Utilization rates were adjusted using annual relative proportions of age groups and stratified according to patient demographics, payer type, and provider state.

For the decade under examination, age-adjusted ED neuroimaging utilization rates per 1,000 ED visits increased 72% overall (compound annual growth rate [CAGR] 5%). Specifically, the utilization of head CT and CTA of the head and neck continuously increased in those aged 65 or older by 48% (CAGR 4%) and 1,011% (CAGR 24%), far outpacing that of other neuroimaging modalities.

“The appropriateness of this growth should be monitored as the indications for CTA expand and more incidental findings are uncovered,” the authors of the AJR article caution.