Rechargeable deep brain stimulation implantable pulse generators in movement disorders: Patient satisfaction and conversion parameters

Objectives Rechargeable (RC) implantable pulse generators (IPGs) for deep brain stimulation (DBS) in movement disorders have recently become available. No guidelines exist for parameter adjustment after conversion of non-RC to RC IPGs, or reports of patient satisfaction with RC IPGs when used as initial DBS device or after conversion from non-RC IPGs. Materials and Methods Patients who underwent placement of Activa RC IPG (Medtronic, Inc.) were surveyed by phone about device satisfaction. Their charts were retrospectively reviewed and DBS settings were analyzed. The stimulation settings before and after conversion to RC were compared. Results Thirty-one patients (age 15-90; 18 male) with movement disorders (nine Parkinson's disease, nine dystonia, eight essential tremor, five others) were identified. Twelve subjects had initial RC IPG implantation; 19 were converted from non-RC IPGs (Soletra; Medtronic, Inc.) 2-14 years after initial DBS implant (mean 6.3 ± 3.44 years). Twenty-six patients (17 conversions) were surveyed an average of 12.1 months since RC IPG implantation. Overall satisfaction with RC was high. Patients converted to RC were more likely to choose it again than those with initial RC. Patients denied differences in symptom control after conversion. Mean amplitude, pulse width, and frequency were slightly lower after conversion regardless of diagnosis and remained lower after three postconversion reprogramming with slow drift of amplitude back to preconversion settings, more in the GPi group. Conclusions RC IPGs in DBS for movement disorders are well received by patients as initial therapy and after conversion. Mild reduction in stimulation parameters might be allowed after conversion to RC IPG.