Post-traumatic intention tremor--clinical features and CT findings.

Eight patients with post-traumatic intention tremor were reported. Intention tremor developed in the young as a late complication of severe head injury (Glasgow Coma Scale was below 8 in all cases) and impaired their functional outcome. This state was treatable with medication or by stereotactic thalamotomy. Neurologically, all the patients lapsed into coma immediately after the injury and many patients manifested clinical signs of a midbrain lesion in the chronic stage. The characteristic CT (computed tomography) findings in the acute stage were a high density area in the midbrain, accompanied by diffuse cerebral swelling or intraventricular hemorrhage, and in the chronic stage, brain atrophy or ventricular enlargement were the most prominent CT findings. These characteristics, indicating diffuse brain damage in addition to midbrain injury, may suggest the presence of shearing injury. The midbrain damage is consistent with the classical hypothesis that the damage to the Dentate-Rubro-thalamic system accounts for the occurrence of intention tremor. Furthermore, the presence of diffuse brain damage suggests that a more widespread brain injury may participate in its development.