Successful Bilateral Subthalamic Nucleus Stimulation for Segmental Dystonia after Unilateral Pallidotomy

Background: Several subcortical structures have been targeted for surgical treatment of dystonia, including motor thalamus, internal segment of globus pallidus (GPi), and more recently, the subthalamic nucleus (STN). Deep brain stimulation of GPi is currently the preferred surgical treatment, but it is unclear if targeting other structures would yield better results. Patients who have already had a pallidotomy yet continue to experience dystonic symptoms may be limited in further treatment options. Methods: A patient with medically intractable, segmental, early-onset, primary torsion dystonia presented for surgical consultation after exhausting nearly all treatment options. Medications, botulinum toxin injections, cervical denervation surgery, and left-sided pallidotomy failed to give adequate relief. The patient was implanted with STN stimulating leads bilaterally according to standard procedures. Results: The patient received a 36% improvement in dystonic symptoms as measured by several dystonia rating scales. These benefits persisted for 2 years after surgery despite several hardware-related complications, and the patient reported being very satisfied with the outcome. Conclusion: This result supports the efficacy of STN deep brain stimulation in dystonia patients, even those with prior pallidotomy.