Interleaving stimulation mode can improve better the health-related quality of life in primary generalized or segmental dystonia than standard bilateral pallidal deep brain stimulation

Abstract

For the treatment of drug-refractory dystonia, bilateral pallidal deep brain stimulation (GPi-DBS) is proven to be an efficient option. However, a considerable portion (10–25%) of patients experience minimal alleviation despite good electrode placement. These patients can be regarded as non-responders to GPi-DBS. In cases series, the interleaving stimulation mode (ILSM) could improve dystonia in patients not responding to standard stimulation techniques. T In this prospective, randomized, double-blind and cross-over study, 34 patients with primary generalized or segmental dystonia were enrolled. Patients underwent four visits: (1) preoperative, (2) prestimulation (4 weeks after electrode implantation BUT before turning on the stimulation), (3) 3 months and (4) 6 months stimulation. Based on electrode location, the best two contacts were activated with submaximal amplitude, 120 μs, and 130 Hz. Patients were randomly assigned to either DMSM-ILSM or ILSM-DMSM sequence. Changes in Burke-Fahn-Marsden DRS, health-related quality of life (SF-36) and side-effects were compared Thirty patients completed the study protocol. A linear mixed model analysis was used to compare the efficacy of the two stimulation modes. The dystonia severity (DRS) significantly improved from the preoperative 33 points (median) to 10 points (median) after 6 months of stimulation (p = .001). There was a trend that ILSM was more efficient (p = .094). The SF-36 improved significantly from the preoperative 49 (median) to 74 (median) after 6 months stimulation (p = .001). The ILSM was superior to the DMSM (p = .010). Although the interleaving stimulation was only tendentiously better at reducing dystonia severity, it was associated with better health-related quality of life.