RESUMO
Bilateral pallidotomy was performed in a schizophrenic patient with severe jaw-opening dystonia developed after chronic neuroleptic treatment. The dystonia led to sustained mandibular joint dislocation, and tracheotomy was performed after suffocation. The jaw-opening dystonia disappeared immediately following pallidotomy; the tracheotomy was closed, and he regained eating and speech ability. Analysis of the neuronal firing of the globus pallidus revealed low neuronal firing rates in the internal pallidum (GPi) and an irregular burst pattern of the GPi cells compared to those in Parkinson's disease. These results suggest that pallidotomy is a treatment option for tardive jaw-opening dystonia and that dystonia of this type is driven by abnormal neural activities in the GPi.