Efficacy of unilateral deep brain stimulation of the thalamic ventralis intermedius nucleus in a patient with bipolar disorder associated with Klinefelter syndrome and essential tremor

Deep brain stimulation (DBS) of the ventralis intermedius nucleus (Vim) is a safe and effective treatment for essential tremor. Bipolar disorder and essential tremor had each been reported to occur in association with Klinefelter syndrome but the three diseases have been reported to occur together in only one patient. The genetic basis and natural history of these disorders are not completely understood and may be related rather than coincidental. The authors report on a 23-year-old man with Klinefelter syndrome (47,XXY) and bipolar disorder who was treated successfully with unilateral DBS of the thalamic Vim for essential tremor.