Deep brain stimulation in belly dancer´s dyskinesia
Schrader C1, Capelle H2, Kinfe T2, Dengler R1, Krauss JK2
1 Dept. of Neurology and Clinical Neurophysiology, Hannover Medical School, Hannover, Germany
2 Dept of Neurosurgery, Hannover Medical School, Hannover, Germany

The term belly dancer's dyskinesia was first used in 1990 in an article describing five patients with focal dyskinesias affecting the abdominal wall. The clinical characteristics of the dyskinesias are somewhat variable, usually consisting of writhing movements and contractions of the abdominal muscles. These movements cannot be voluntarily suppressed. The onset is usually gradual. An antecedent of local trauma or surgical procedures of the abdomen may be present in half of the cases. Investigations, such as spinal and abdominal imaging, fail to reveal any abnormality that could explain the movement disorder. The prognosis is quite unfavorable because no effective treatment exists. Thus, the clinical course is long-lasting or permanent. Here we report a case of belly dancer´s dyskinesia treated with bilateral deep brain stimulation (DBS) of the internal globus pallidus (GPi).

This 78-year-old woman noticed progressing semirhythmic dyskinetic contractions of the abdominal wall resulting in writhing of the trunk first at the age of 75. There was no history of antecedant local trauma, tumor, surgical procedure, or anti-dopaminergic treatment. MRI revealed no circumscribed lesion. Since several oral drug approaches were only of transient and limited effect she was selected for pallidal DBS.

Quadripolar electrodes were placed stereotactically in the posteroventral lateral part of the internal part of the globus pallidus. Microelectrode recordings were performed additionally for optimal target localisation. Clinical evaluation employed the Burke-Fahn-Marsden-Dystonia-Rating-Scale (BFMDRS) and the Unified Dystonia Rating Scale (UDRS) ratings which were obtained prior to surgery, one-week post-operatively and at nine-months-follow-up using video-based rating.

Bipolar high frequency stimulation starting at 130 Hz, 210 µs, and four V clearly suppressed belly dancer´s dyskinesia significantly for six weeks. Subsequent waning of the effect of stimulation required continuous adjustment of stimulation parameters. At nine months follow-up the segmental dystonia showed moderate improvement in both UDRS and BFMDRS. DBS was well tolerated.

GPi DBS was an effective option in this patient with belly dancer´s dyskinesia for an observation period of nine months. Further follow-up is needed to judge long-term efficacy.