Background: Multiple, validated, evidence-based guidelines exist to inform the appropriate use of computed tomography (CT) to differentiate mild traumatic brain injury (MTBI) from clinically important brain injury and to prevent the overuse of CT. Yet, CT use is growing rapidly, potentially exposing patients to unnecessary ionizing radiation risk and costs. A study was conducted to quantify the overuse of CT in MTBI on the basis of current guideline recommendations.
Methods: A retrospective analysis of secondary data from a prospective observational study was undertaken at an urban, Level I emergency department (ED) with more than 90,000 visits per year. For adult patients with minor head injury receiving CT imaging at the discretion of the treating physician, the proportion of cases meeting criteria for CT on the basis of the Canadian CT Head Rule (CCHR), American College of Emergency Physicians (ACEP) Clinical Policy, New Orleans Criteria (NOC), and National Institute for Health and Clinical Excellence (NICE) guidelines was reported.
Results: All 346 patients enrolled in the original study were included in the analysis. The proportion of cases meeting criteria for CT for each of the guidelines was: CCHR 64.7% (95% confidence interval [CI], 0.60-0.70), ACEP 74.3% (95% CI, 0.70-0.79), NICE 86.7% (95% CI, 0.83-0.90), and NOC 90.5% (95% CI, 0.87-0.94). The odds ratio of the guidelines for predicting positive head CT findings were also reported.
Discussion: Some 10%-35% of CTs obtained in the ED for MTBI were not recommended according to the guidelines. Successful implementation of existing guidelines could decrease CT use in MTBI by up to 35%, leading to a significant reduction in radiation-induced cancers and health care costs.