Inclusion Criteria:  Patient aged ⩾ 75 years who had a brain scan without contrast injection in the emergency department due to isolated confusional syndrome between January 1, 2019 and December 31, 2019. French-speaking patient  Exclusion Criteria:  Patient with concomitant localizing neurological signs of confusional syndrome: abnormalities of the cranial pairs, unusual headaches, meningeal syndrome, cerebellar syndrome, systematized sensory or motor deficit, vestibular syndrome, Glasgow Coma Scale score ≤ 8. Patient who has had a head injury and is taking a long-term antiplatelet and/or anticoagulant therapy. Patient objecting to the use of their data for this research. Patient deprived of liberty Patient under court protection