Table 2.
Overview of randomized clinical trials on deep brain stimulation of the globus pallidus internus
| Study | Design | n | Age, years (mean ± SD) | Duration of disease, years (mean ± SD) | Stage of disease (H&Y scale) | Unilateral (U) or bilateral (B) |
|---|---|---|---|---|---|---|
| Burchiel et al. [88] | Randomized, blinded pilot study | 4 | 46.5 ± 11 | 10.6 ± 2 | 4.0 (4.0–4.8) | B |
| Katayama et al. [89] | Double blinded evaluation | 7 | 5U, 2B | |||
| Anderson et al. [23] | Randomized, blinded, parallel- group study | 10 | 54 ± 12 | 10.3 ± 2 | 4–4.5 | B |
| DBS for Parkinson’s Disease Study Group et al. [24] | Prospective, double-blinded, randomized crossover trial | 38 | 55.7 ± 9.8 | 14.5 | B | |
| Rodriguez-Oroz et al. [26] | Multicenter, double blinded, non-randomized trial | 20 | 55.8 ± 9.4 | 15.4 ± 6.2 | 3.0–5.0 | B |
| Follett et al. [25] | Multicenter, randomized, blinded trial | 152 | 61.8 ± 8.7 | 11.5 ± 5.4 | 3.3 ± 0.9 | B |
| Weaver et al.a[27] | RCT | 61 | 62.4 ± 8.8 | 10.8 ± 5.4 | ≥ 2 | B |
| Robertson et al. [90] | Randomized double-blinded controlled trial | 13 | 65.5 ± 8.6 | 15.1 ± 10.2 | 3.5 ± 0.8 | B |
| Weaver et al. [28] | Multicenter RCT | 89 | 60.4 ± 8.3 | 11.4 ± 4.9 | 3.3 ± 0.8 | B |
| Okun et al. [29] | Prospective, blinded RCT | 23 | 60.2 ± 6.2 | 12.5 ± 3.6 | 2.0–5.0 | U |
| Rocchi et al. [91] | Randomized | 14 | 61.1 ± 8.4 | 12.9 ± 10.17 | 3.5 ± 0.9 | B |
| Odekerken et al. [30] | RCT | 65 | 59.1 ± 7.8 | 10.8 ± 4.2 | 2.5 (0–4) | B |
| Moro et al. [92] | Nonrandomized, multicenter study | 16 | 56.0 ± 2.1 | 15.1 ± 1.5 | 3.9 ± 0.2 | B |
| Rothlind et al. [31] | Prospective, randomized, controlled study | 80 | 61.3 ± 8.9 | 11.0 ± 4.7 | 3.2 ± 0.8 | B |
| Zahodne et al. [87] | RCT | 22 | 61.3 ± 5.5 | 12.4 ± 3.6 | U | |
| St George et al. [93] | RCT | 10 | 62.8 ± 8.2 | 15.4 ± 8.4 | B |
| Study | Follow-up/study duration (months) | UPDRS II changes: MED OFF, DBS ON vs. OFF | UPDRS-III changes: MED OFF, DBS ON vs. OFF | Change in medication or LEDD (%) | Change in dyskinesias (%) | Change in quality of life (%) | Main findings |
|---|---|---|---|---|---|---|---|
| Burchiel et al. [88] | 12 | 39% improvement | No significant change | 47% improvement | Schwab and England scale 63% improvement | Pallidal and STN stimulation appears to be safe and efficacious for management of advanced PD | |
| Katayama et al. [89] | 8 | 57% improvement | No significant change | Stimulation ON vs. OFF resulted in 57% improvement in UPDRS for GPi | |||
| Anderson et al. [23] | 12 | 18% improvement | 39% improvement | No significant change | 89% improvement | Stimulation of either GPi or STN improves many features of advanced PD | |
| DBS for Parkinson’s Disease Study Group et al. [24] | 6 | 35.8% improvement | 33.3% improvement | No significant change | 36% improvement | Bilateral stimulation of the STN or GPi is associated with significant improvement in symptoms of PD | |
| Rodriguez-Oroz et al. [26] | 36–48 | 7.6% improvement | 39% improvement | No significant change | 72% duration reduction, 76% severity reduction | Long-term efficacy of either STN or GPi stimulation shows a significant and substantial clinically important therapeutic benefit for at least 3–4 years in a large cohort of severe PD patients | |
| Follett et al. [25] | 24 | 17.3% improvement | 28.2% improvement | 17.9% decrease | 38.6% improvement | 11.2% improvement | Similar improvement in PD symptoms with either pallidal or subthalamic stimulation |
| Weaver et al.a[27] | 6 | 24.1% improvement | 28.9% improvement | 23.1% decrease | 37% improvement | 17.1% improvement | DBS is more effective than best medical therapy |
| Robertson et al. [90] | 6 | 32.1% improvement | DBS in GPi did not significantly worsen jaw velocity 6 months after surgery | ||||
| Weaver et al. [28] | 36 | 8.6% improvement | 34.1% improvement | 17.8% decrease | 51.7% improvement | 6.4% improvement | Improvement of motor symptoms of PD by DBS remains stable over 3 years and does not differ by surgical target |
| Okun et al. [29] | 7 | 26.6% improvement | No significant changes in mood and cognition between STN and GPi in optimal DBS state. GPi and STN have similar motor improvement | ||||
| Rocchi et al. [91] | 6 | 32.2% improvement | 16.0% decrease | DBS at 6 months can impair step initiation | |||
| Odekerken et al. [30] | 12 | 21.8% improvement | 26.0% improvement | 15.6% decrease | 16.7% improvement | Schwab and England scale 20% improvement | No difference in outcomes between STN and GPi, but suggestion that STN may be preferred target |
| Moro et al. [92] | 60–72 | 25.8% improvement | 35.1% improvement | No significant change | 75% improvement | Confirmation of effectiveness of GPi and STN stimulation long term (5–6 years), with preoperative reponse to L-DOPA predicting long-term benefit with both targets | |
| Rothlind et al. [31] | 6 | 80.3 ± 105.3 PDQ-39 total scorea | In patients with PD, likelihood of neuropsychological decline increases with DBS | ||||
| Zahodne et al. [87] | 6 | 28.0% improvement | 8.4% increase | 38.1% improvement | Quality of life overall improved, with improvement reported to be greater in GPi than STN | ||
| St George et al. [93] | 6 | 27.9% improvement | 20.5% decrease | DBS did not improve compensatory step response needed to recover from balance perturbations in the GPi group |
DBS Deep brain stimulation, H&Y Hoehn and Yahr, LEDD levodopa equivalent daily dose, MED OFF, off-medication, PD Parkinson’s disease, PQD-39 39-item Parkinson's Disease Questionnaire, RCT randomized controlled trial, SD standard deviation, STN subthalamic nucleus, UPDRS Unified Parkinson’s Disease Rating Scale
aCombined GPi and STN result