Utilization of CT angiography of the head and neck in the era of endovascular therapy for acute ischemic stroke: a retrospective study

PurposeTo describe the impact of a new institutional Code Stroke protocol on ordering volume of head and neck CT angiographies (CTA), and to determine the number and proportion of these studies that resulted in an endovascular or surgical intervention.MethodsClinical and administrative data was collected on all head and neck CTAs ordered within the ED at two high-volume community hospitals and an affiliated urgent care centre during the 6-year period between January 1, 2014, and December 31, 2019. Of those patients who underwent CTA, we identified those who were then transferred to a regional stroke centre for consideration of EVT and those who underwent carotid endarterectomy or stenting within 14 days.ResultsA total of 4719 CTAs were ordered during the 6-year period. There was nearly a tenfold rise in the yearly number of CTAs ordered per 10,000 ED visits, from 5.3 (in 2014) to 53.1 (in 2019). A total of 164 patients who underwent CTAs (3.5%) were ultimately transferred to a regional tertiary care centre, of whom 43 (0.9%) were transferred to a regional stroke centre for consideration of EVT. A total of 61 (1.3%) patients underwent a carotid intervention within 14 days.ConclusionLittle is known of the impacts on healthcare resources that have resulted from the system-wide changes made necessary by the widespread adoption of EVT. Our study shows that at our site, these system changes have resulted in large increases in CTA utilization with very small numbers of patients ultimately undergoing EVT or carotid intervention.