The Relationship of Electrophysiologic Subthalamic Nucleus Length as a Predictor of Outcomes in Deep Brain Stimulation for Parkinson Disease

Abstract

Background: Intraoperative measurement of subthalamic nucleus (STN) width through microelectrode recording (MER) is a common proxy for optimal electrode location during deep brain stimulation (DBS) surgery for Parkinson disease. We assessed whether the MER-determined STN width is a predictor of postoperative Unified Parkinson Disease Rating Scale (UPDRS) improvement. Methods: Records were reviewed for patients who underwent single-sided STN DBS placement for Parkinson disease between 2005 and 2010 at the UAB Medical Center. Reviews of preoperative and 3-month postoperative UPDRS part III, intraoperative MER records, and postoperative MRI scans were conducted. Results: The final cohort consisted of 73 patients (mean age 59 ± 9.7 years, length of disease 13 ± 9.7 years). STN widths were defined as depths associated with increased background activity and motor-driven, spiking action potentials on MER. The mean contralateral UPDRS improvement was 58% (± 24). The mean STN width was 5.1 mm (± 1.6, min = 0.0, max = 8.7). No significant relationship between STN width and UPDRS improvement was found, with and without AC-PC normalization (R² < 0.05). Conclusion: This analysis raises questions about seeking the maximal electrophysiological width of STN as a proxy for optimal outcome in DBS for PD. We suggest this strategy for DBS placement in Parkinson disease be subject to more robust prospective investigation.

Multiple Microelectrode Recordings in STN‐DBS Surgery for Parkinson's Disease: A Randomized Study

“…Some centers use one MER and adding more if needed, the single sequential approach, usually using the length of STN signals as a criterion. However, there is no certain significant relationship between STN length and UPDRS improvement . Also, with this approach, it may be difficult to recognize too medially placed electrodes .…”

Role of plasminogen activator inhibitor‑1 in the diagnosis and prognosis of patients with Parkinson's disease

“…At present, intraoperative measurement of subthalamic nucleus width via microelectrode recording is a common proxy for optimal electrode location during deep brain stimulation (DBS) surgery for patients with Parkinson's disease (12). However, to the best of our knowledge, the role of PAI-1 in evaluating the therapeutic effects of DBS has not been investigated in patients with Parkinson's disease.…”

Parkinson’s Disease: Deep Brain Stimulation

“…A recent study reported an average error of 2.2 mm in the X-coordinate and of 2.0 mm in the Y-coordinate that would have corresponded to misplaced DBS electrode placement in ~20% of all DBS implants, had MER not been performed [51], but this study was poorly controlled. Although Shenai et al [52] found a 58% improvement in post-op UPDRS scores with MER mapping, no statistical difference was found for STN spans of <4.8 mm as compared to >5.6 mm. However, in all 73 cases, MER did confirm that the target was within the dorsolateral STN.…”