We aimed to conduct a prospective longitudinal interventionnal monocentric study to assess the ability of seven tesla MRI to detect diffuses axonal lesions in patients presenting a post concussional syndrom (PCS) at seven days about a mild traumatic brain injury (MTBI). Our first objective was to evaluate the diagnostic performance of seven tesla MRI runned at seven days after MTBI among patients presenting a PCS.

Among patients admitted in emergency care units in France for mild traumatic brain injury, 10 % will develop post concussionnal symptoms. The variability of the clinical presentation lead to a syndrome at the border of neurology, psychiatry and neuro-traumatology. Ninety per cent of these patients will have a favorable evolution in three to six months while ten per cent will have persistant symptoms : dizziness, headache, nausea, drowsiness, anxio-depressive symptoms, irritability, memory impairments, attentionnal disorders. This conduct to an additionnal medical and social cost (medical re-consultation in emergency services, pharmaceutical expenditure due to over medication, social recognition, deterioration of social and professionnal relationships …). The litterature data show the presence of diffuse axonal lesions (DAL) frequently observed in patients victims of MTBI. These lesions seemed to be correlate with the occurrence of post concussional symptoms. New brain imagery have lead to these discoveries but are not relevant in clinical routine (functionnal MRI, Diffusion Tensor Imaging, tractography). Computed Tomography is often normal and not able to detect these lesions. Standard MRI is not enough sensible for the detection of the DAL. Some autor shows alose that his sensibility decrease in time.

These observations and encouraging results lead us to initiate a prospective interventionnal, longitudinal, pilot study monocentric using seven tesla MRI to evaluate its input in the detection of diffuse axonal lesions among patients presenting post concussionnal symptoms after a mild traumatic brain injury at day seven after they are admitted to our emergency service.

Inclusion Criteria:

• Mild traumatic brain injury with glascow included between 13 and 15, with indication of scan
• possibilty of performing an MRI at 7 days
• Patient able to get to MRI at Day 7
• Free consentement to the study
• Any measure of guardianship or curatorship , any link of subordination

Exclusion Criteria:

• Patient does not hospitalized about head trauma
• Inhability to move out for run the seven day MRI
• Contraindication for MRI
• Patient having already consulted the emergency for head trauma requiring imaging
• Patients with psychiatric troubles : bipolarity, panic trouble, depressive trouble, schizophrenia
• Patient already enrolled in the study
• History of brain, tumor or neurosurgery
• Untreated or poorly treated chronic vertigo
• Untreated or poorly treated chronic migraines
• Claustrophobia
• BMI > 40
• Refusal of consent to take part of the study
• No social welfare or inhability to benefit of it by a third party
• Patients with enhanced protection : minor aged under 18 ; person with freedom restriction by justice decision or administrative ; homeliving in health or social establishment ; adult in legal protection
• Pregnant and nursing women