[CT scan in syncope : diagnostic yield and prescription habits]

Syncope is a frequent reason for emergency department admission. Brain imaging is theoretically not recommended. After exclusion of features orienting towards non-syncopal events, we retrospectively included 206 patients who underwent head CT scans in the University Hospital of Liège for transient loss of consciousness between December 2020 and July 2021. We surveyed physicians involved in the emergency department concerning their imaging prescription habits and motivations. CT diagnostic yield is 1 %. The oncologic background is associated with pathological findings (odds ratio 84,1, p = 0,005). Cervical angio-CT scans only lead to incidental findings and increased dose exposure. Only a minority (6.6 %) of physicians systematically prescribe brain imaging. Radioprotection is an important notion for only 10 % of the less experimented physicians. Obligation of means is an occasional justification for resort to imaging. A prospective decisional rule based on the exclusion of features orienting towards non-syncopal loss of cousciousness, old age and oncologic history might reduce the number of useless scans. Radioprotection is too often neglected by less experimented physicians. Obligation of means should not be mingled with reassurance behaviors as part of defensive medicine.