Evaluation of a programming algorithm for deep brain stimulation in dystonia used in a double-blind, sham-controlled...

Area of Science:

• Neurology
• Neurosurgery
• Biomedical Engineering

Background:

• Programming deep brain stimulation (DBS) for dystonia is challenging due to delayed effects and lack of guidelines.
• Pallidal DBS is a treatment for dystonia, but optimal programming strategies are needed.

Purpose of the Study:

• To evaluate the efficacy of a novel programming algorithm for pallidal deep brain stimulation in dystonia patients.
• To determine if acute programming responses predict long-term outcomes.

Main Methods:

• A double-blind, sham-controlled, multicenter study involving 40 dystonia patients.
• Standardized monopolar review to identify optimal stimulation contacts, followed by programming below the adverse effect threshold.
• Long-term follow-up (3 and 5 years) assessing motor scores and adverse events.

Main Results:

• Significant motor score improvement observed at 3 and 5 years, with mean decreases of 73% and 63% respectively in patients showing acute improvement.
• Contacts without acute benefit also showed improvement (58% at 3 years, 53% at 5 years).
• Acute worsening or induction of dystonia/dyskinesia correlated with 3-year improvement, but not 5-year outcomes.

Conclusions:

• The programming algorithm, utilizing monopolar review, identified effective therapeutic contacts in about 30% of patients.
• Both acute improvement and worsening of dystonic symptoms during programming predicted favorable long-term outcomes.
• Induction of phosphenes did not correlate with treatment efficacy.