Abnormal involuntary movements and hydrocephalus

Background: Abnormal involuntary movements have been described in patients with hydrocephalus. However, the etiopathogenesis of this association has not been clarified. We study the presence of dyskinesia, as well as its clinical and demographic characteristics in patients with hydrocephalus. Design and patients: Series of cases studied during a 10-year period in a neurologic service of a third-level reference hospital. Nine subjects, 6 men and 3 women (mean age: 67 years) in whom hydrocephalus proceded dyskinesia. Results: Hydrocephalus preceded in 2.33 years the appearance of dyskinesia. Dyskinetic symptoms included tremor in 6 patients, parkinsonism in 1, and dystonia in 2. Five of these patients had family history of dyskinesia in parents or siblings. In 4 of them, the placement of a ventriculoperitoneal shunt improved the abnormal movements. Conclusion: Hydrocephalus may trigger dyskinesia (tremor, parkinsonism, and cranial- cervical dystonia) in a group of susceptible patients who are in their sixties and have a family history of movement disorders. It is possible that hydrocephalus due to mechanic distortion or to alteration of blood flow to the basal ganglia or both, causes an unbalance between the central and the peripheral impulses for tremor and parkinsonism to appear; on the other hand, it might unlock the control that basal ganglia exert on the motor-neurones of the trigeminal and facial motor nuclei thus triggering the cranial-cervical dystonia.