Long-term Outcome of Globus Pallidus Internus Stimulation for Pisa Syndrome.

Pisa syndrome, defined as dystonia leading to lateral flexion of the spine, is an increasingly recognized complicating factor in the treatment of Parkinson's disease (PD). Symptoms may persist despite medical therapy, or medical therapy may not be tolerated due to adverse effects. Here, we demonstrate the long-term efficacy of deep brain stimulation (DBS) at the globus pallidus internus (GPi) for the treatment of Pisa syndrome. One patient with Pisa syndrome and Parkinson disease underwent bilateral GPi DBS with computed tomography (CT)-and microelectrode-based guidance. Follow-up with neurosurgery and neurology was done over a four-year period. The patient's axial deformity decreased from approximately 45 to 25 degrees, and he reported significant relief from back pain. Bilateral GPi DBS is a safe and effective option for Pisa syndrome in patients with PD.