Hemiparkinsonism after unilateral traumatic midbrain hemorrhage in a young woman.

The relationship between head trauma and parkinsonism has been debated since James Parkinson's first description of the shaking palsy in the late 19th century. We observed in our outpatient clinic a young woman in whom hemiparkinsonism developed within 3 weeks of sustaining closed head trauma with loss of consciousness. The patient had a discrete unilateral midbrain hemorrhage on head MRI which involved the contralateral substantia nigra. The condition responded well to carbidopa/levodopa. This patient is a convincing example of posttraumatic midbrain hemorrhage causing parkinsonism.