[CT-scan in the emergency department : the right indications, the right timing].

A general increase in the use of CT-scans was observed during the last decade, in part due to its ease of access but also due to the increasing precision of this exam in establishing a diagnosis. This is particularly true in emergency departments where the increase in the number of CT-scan prescribed may impact patient's flow. A reminder of the recommendations for prescribing CT-scans and the time required to obtain them for the most frequently encountered pathologies could help to better target patients who are most likely to benefit from this examination and reduce the consequences of its over-use (radiation, increased costs, timing).