OBJECTIVE: To evaluate the short-term and long-term clinical effectiveness and 
safety of subthalamic nucleus deep brain stimulation (STN-DBS) for medically 
intractable pediatric isolated dystonia.
METHODS: Using a longitudinal retrospective design, we assessed the clinical 
outcomes of nine patients who underwent STN-DBS for treatment-refractory 
pediatric isolated dystonia one decade ago (mean age at surgery: 15.9 ± 4.5 
years). The primary clinical outcome used was assessed by retrospective video 
analyses of patients' dystonia symptoms using the Burke-Fahn-Marsden Dystonia 
Rating Scale (BFMDRS). Clinical assessments were performed at baseline, 1-year 
follow-up (1-yr FU), and 10-year follow-up (10-yr FU). Adverse side effects, 
including surgery-related, device-related, and stimulation-related effects, were 
also documented.
RESULTS: After STN-DBS surgery, the mean improvement in the BFMDRS motor score 
was 77.1 ± 26.6% at 1-yr FU and 90.4 ± 10.4% at 10-yr FU. Similarly, the mean 
BFMDRS disability score was improved by 69.5 ± 13.6% at 1-yr FU and by 86.5 ± 
13.9% at 10-yr FU. The clinical improvements gained at 10-yr FU were 
significantly larger than those observed at 1-yr FU. Negative correlations were 
found between the duration of disease to age at surgery ratio (DD/AS) and the 
improvements in the BFMDRS motor score and total score at 1-yr FU and 10-yr FU.
CONCLUSION: To our knowledge, this study provides the first clinical evidence 
for the short- and long-term effectiveness and safety of STN-DBS for pediatric 
isolated dystonia. Additionally, putative evidence is provided that earlier 
STN-DBS intervention in patients with refractory pediatric isolated dystonia may 
improve short- and long-term clinical outcomes.