Pallidal deep brain stimulation in patients with primary generalised or segmental dystonia: 5-year follow-up of a randomised trial

Designing Clinical Trials for Dystonia

“…Botulinum toxin injections must be repeated every few months, are best suited for those with focal or segmental dystonias, and not all patients respond or maintain responsiveness, which may contribute to inadequate patient satisfaction [1,2]. While surgical approaches can be quite effective for generalized and refractory segmental dystonias [3,4], patient selection criteria are not well established, the benefit may be incomplete, the durability is not fully characterized, and there are inherent risks [5].…”

Dystonia - new advances in classification, genetics, pathophysiology and treatment

“…All of these groups have during recent years also published long-term outcomes in their patients. At 3 years follow-up, mean improvement in the motor part of the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) was 58% in the French study (38) and 61% in the German study (39), thus a further significant improvement compared with results at the 6 months follow-up. In the German study, 5 years follow-up data were also available and showed a sustained efficacy, both in the generalized and segmental dystonia group (39).…”

“…At 3 years follow-up, mean improvement in the motor part of the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) was 58% in the French study (38) and 61% in the German study (39), thus a further significant improvement compared with results at the 6 months follow-up. In the German study, 5 years follow-up data were also available and showed a sustained efficacy, both in the generalized and segmental dystonia group (39). The Montpellier group have observed worsening of dystonia after many years of very effective bilateral GPi-stimulation in some of their primary generalized dystonia patients and have shown that implanting a second pair of electrodes (on average 4.5 years after the first pair) can improve outcome in some of these patients (40).…”

“…Five descriptors are utilized to specify the clinical features axis: age at onset, body distribution, temporal pattern, coexistence of other movement disorders, and coexistence of other neurological or systemic manifestations. Age at onset is divided into infancy (0-2 years), childhood (3-12 years), adolescence (13-20 years), early adulthood (21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40), and late adulthood (>40 years). Body distribution is, as in earlier classifications, divided into focal, segmental, multifocal, generalized, and hemidystonia.…”

Treatment of Dystonia

“…Subsequently, all patients completed an open-label extension of 6 months total active treatment. Further follow-up demonstrated significant improvements in dystonia at 3 and 5 years [47]. Since then, other long-term studies have been reported, including 1 retrospective cohort study of 47 DYT1-positive patients treated with GPi, followed for up to 96 months (mean, 46 months) [48].…”