RESUMO
An 18-year-old man suffered a severe head trauma from a car accident. Eight months later the patient had a good general state of health. But at this time he was referred to our psychiatric hospital and he reported increased checking compulsions and aggressive obsessions. In addition there was increased impulsivity. The patient was treated with an selective-serotonin-reuptake-inhibitor (SSRI) and showed a clinical response. Obsessive-compulsive disorder (OCD) has rarely been described after traumatic brain injury. Clinical symptoms, neuropsychological dysfunctions, brain imaging and therapy are illustrated. The represented connections of the frontal brain lesions and OCD-symptoms with interventions in the serotonin system support the neurobiological hypotheses of the obsessive-compulsive disorder.