Canadian CT Head Rule may be best, but fails to curb imaging

The Canadian CT Head Rule provides a sensitive, specific and cost-effective clinical prediction rule, according to a systemic review published in the September issue of Annals of Emergency Medicine.

As the number of emergency department patients evaluated for head trauma has climbed to 1.4 million annually, the need to safely reduce advanced neuroimaging has become clear. Appropriate use of CT can reduce radiation exposure risk, target healthcare resources and rein in costs.

Dylan D. Cooper, MD, and Rawle A. Seupaul, MD, from the department of emergency medicine at Indiana University School of Medicine in Indianapolis, undertook a systemic analysis of studies that examined externally validated rules: the Canadian Head CT Rule and New Orleans Criteria. A total of 222 studies were reviewed, and 19 trials were selected for analysis.

“Although the New Orleans Criteria rule was highly sensitive, it lacked specificity, precluding it from excluding a meaningful number of patients from radiographic imaging,” write Cooper and Seupaul. The Canadian Head CT Rule provided high sensitivity for injuries requiring neurointervention, and greater specificity.

However, although research has suggested the Canadian clinical prediction rule was the most cost-effective decision tool to safely reduce advanced neuroimaging among patients with minor head trauma, another study showed it did not reduce use of neuroimaging. In some organizations, the use of advanced neuroimaging increased after the rule was applied.

“Despite these findings, this systematic review supports the use of the Canadian CT Head Rule to tailor neuroimaging strategies for ED patients with minor head trauma,” concluded the authors.