Table 2.
Description of studies comparing STN and GPi as targets for Deep Brain Stimulation in Parkinson’s disease.
| First Author | Year | Study Design | Number of Participants/ Inclusions | Findings | Narrative Summary |
|---|---|---|---|---|---|
| Anderson et al. | 2005 | Randomized, parallel blinded study | 23 (20 at follow-up) | Both GPi and STN DBS improve medication OFF motor scores | • Randomized to GPi or STN DBS • They were assessed at baseline and follow-up • OFF medication motor improvement 39% in GPi • OFF medication motor improvement 48% in STN |
| Wong et al. | 2020 | Retrospective review of outcome | 88 (57 STN and 31 GPi) | Both GPi and STN DBS decrease action- and rest tremor | • Retrospective assessment of STN or GPi DBS • At 6 months, STN was superior in reducing action tremor • Effect was not present at 12 months. |
| Weaver et al. | 2009 | Randomized, assessor blinded, controlled trial | 235 (60 STN DBS, 61 GPi DBS and 134 BMT) | DBS was superior to BMT in achieving maximal ON time | • Randomized trial • Six months follow up • DBS patients, regardless of targeting better symptom control at six months • More ON time at 6 months • Improvement in quality of life in the DBS group. |
| Odekerken et al. | 2013 & 2016 | Randomized controlled trial | 128 (65 GPi DBS and 63 STN DBS) | STN was slightly superior to GPi | • Randomized trial of GPi or STN DBS • Follow up after one and three years • No significant difference at one year • OFF medication symptom control, superior in the STN DBS group • Findings were persistent at three years |
| Obeso et al. | 2001 | Clinical trial | 134 (96 STN DBS and 38 GPi DBS) | STN slightly preferred at six months compared to GPi | • Comparative study of DBS of the STN or the GPi • At six months, STN DBS had better symptom control • At six months, STN had a larger medication reduction |
| Moro et al. | 2010 | Open, non-randomized and later double-blind and randomized, prospective multicenter clinical trial | 51 (35 with STN DBS and 16 with GPi DBS) | STN DBS showed larger symptom reduction, GPi DBS had fewer adverse events | • Mixed design with both • Follow-up after 5-6 years • STN DBS, larger effects on motor symptom severity • STN DBS larger improvement in activities of daily living and subjective quality of life. • GPi DBS associated with fewer adverse events. |
| Liu et al. | 2019 | Systematic review and meta-analysis | 8 studies (822 patients) | GPi superior to STN to reduce dyskinesia at 12 months | • Review of differentiated effects on dyskinesias. • GPi DB better at controlling dyskinesias • STN DBS had a larger reduction in medication |
| Mao et al. | 2019 | Systematic review and Network meta-analysis | 16 studies (1252 patients) | Both GPi and STN similarly improve UPDRS motor symptoms | • Comparison of several targets • GPi and STN similarly suited for symptom reduction • VIM better for tremor dominant PD |
| Xu et al. | 2017 | Systematic review and meta-analysis | 8 studies (522 patients) | STN favored for OFF medication symptom control | • Review of differences in ON and OFF • STN DBS found more favorable • STN DBS led to larger reductions in medication |
| Mansouri et al. | 2018 | Systematic review and meta-analysis | 13 studies | GPi and STN DBS similarly improve UPDRS motor scores at 36 months | • Review of the relative efficacy of STN and GPi DBS • Longest follow-up was 36 months • GPi and STN DBS comparable in improving motor scores. • Medication use less in STN DBS cohort • Depression scores lower in GPi cohort |
| Xie et al. | 2016 | Systematic review and meta-analysis | 16 studies, 2186 participants | GPi and STN DBS similarly improve UPDRS motor scores | • Review of randomized trials of STN, GPi DBS and BMT |
Abbreviations: STN = Subthalamic nucleus, GPi = Globus pallidus internus, DBS = Deep brain stimulation, UPDRS = Unified Parkinsons Disease Rating Scale, PDQ39 = Parkinsons Disease Questionnaire.