Deep brain stimulation (DBS) of single-target nuclei has produced remarkable functional outcomes in a number of movement disorders such as Parkinson's disease, essential tremor, and dystonia. While these benefits are well established, DBS efficacy and strategy for unusual, unclassified movement disorder syndromes is less clear. A strategy of dual pallidal and thalamic electrode placement is a rational approach in such cases where there is profound, medically refractory functional impairment. The authors report a series of such cases: midbrain cavernoma hemorrhage with olivary hypertrophy, spinocerebellar ataxia-like disorder of probable genetic origin, Holmes tremor secondary to brainstem stroke, and hemiballismus due to traumatic thalamic hemorrhage, all treated by dual pallidal and thalamic DBS. All patients demonstrated robust benefit from DBS, maintained in long-term follow-up. This series demonstrates the flexibility and efficacy, but also the limitations, of dual thalamo-pallidal stimulation for managing axial and limb symptoms of tremors, dystonia, chorea, and hemiballismus in patients with complex movement disorders.
Keywords: ADL = activity of daily living; DBS = deep brain stimulation; GPi = globus pallidus interna; HT = Holmes tremor; TRS = Tremor Rating Scale; VIM = ventralis intermedius nucleus of the thalamus; VOP/ZI = ventralis oralis posterior of the thalamus/zona incerta; deep brain stimulation; dystonia; essential tremor; functional neurosurgery; globus pallidus; thalamus.