A 19 years' old white male presented with a stuporous state, initially suspected to be of a toxic origin. It appeared soon that the patient had a left oedematous cerebellar infarction with obstructive hydrocephalus. The angiographic study has shown an occlusion of the left vertebral artery at the level of C2. After reviewing the literature about the different etiologies of vertebral occlusions in the young people, it appeared likewise that, in this case, it was the result of a traumatic compression due to an alcoholic coma. Despite an external ventricular drainage, the neurological state worsened. After a left suboccipital craniotomy and resection of the external part of the cerebellar hemisphere, the state of the patient improved quickly, and he was discharged from hospital with a light cerebellar syndrome.