Reliability of Intraoperative Testing During Deep Brain Stimulation Surgery

Area of Science:

• Neurosurgery
• Neurology
• Medical Engineering

Background:

• Deep brain stimulation (DBS) is a key treatment for Parkinson's disease (PD).
• Intraoperative testing during DBS surgery assesses lead placement by measuring stimulation thresholds.
• The predictive accuracy of intraoperative testing for long-term outcomes remains unclear.

Purpose of the Study:

• To evaluate the reliability of intraoperative testing in predicting postoperative stimulation thresholds for symptom improvement and side effects in PD patients undergoing subthalamic nucleus (STN) DBS.
• To determine if intraoperative findings can accurately forecast the effectiveness and potential adverse effects of DBS after surgery.

Main Methods:

• Retrospective analysis of a prospective database of 66 PD patients who underwent STN DBS.
• Recording stimulation locations relative to the mid-commissural point and clustering intraoperative locations.
• Calculating distances between stimulation sites and atlas-based pyramidal tract (PT) and medial lemniscus (ML) masks.
• Utilizing leave-one-out cross-validation to assess predictive reliability while controlling for anatomical proximity.

Main Results:

• Intraoperative testing demonstrated high reliability (AUC >0.8) in predicting postoperative thresholds for tremor and rigidity improvement.
• It also reliably predicted stimulation-induced motor contractions and paresthesias.
• Prediction accuracy for bradykinesia improvement was notably poor.

Conclusions:

• Intraoperative testing is a reliable predictor of postoperative thresholds in STN DBS for Parkinson's disease.
• Findings support its use in patient counseling and informed consent for DBS surgery.
• Results can inform the development of advanced intraoperative feedback methods, particularly for asleep DBS procedures.