Head trauma is a frequent reason for consultation in the emergency room. The CT scan is the reference examination allowing rapid management of the patient. However, CT examinations are among the diagnostic examinations with the highest exposure to ionizing radiation. The study investigators have previously implemented "ultra-low dose" (ULD) acquisitions for several pathologies with an effective dose level similar to that of a standard radiographic examination. These ULD acquisitions are now routinely used in our clinical practice for explorations of the thorax, spine, pelvis and proximal femurs, extremities.

This study expands these ULD acquisitions to skull CT for detecting traumatic intracranial lesions.

The study investigators hypothesize that it would be possible to search for intracranial lesions in patients with head trauma using ULD protocols, thereby reducing the doses delivered to the patient while maintaining sufficient image quality for the diagnosis.

Inclusion Criteria:

• Patient presenting to the emergency room of the CHU of Nîmes for a cranial trauma requiring scanning.
• Patient with isolated head injury or polytrauma patient with head injury among others.
• The patient or their legal representative or family member must have given their free and informed consent and signed the consent form, or the patient was included under an emergency situation
• The patient must be a member or beneficiary of a health insurance plan

Exclusion Criteria:

• The subject is participating in a study prohibiting participation in other studies, or is in a period of exclusion determined by a previous study
• Patient is pregnant, parturient or breastfeeding