Comparison of anatomic and neurophysiological methods for subthalamic nucleus targeting

Area of Science:

• Neurosurgery
• Neurology
• Medical Imaging

Background:

• Subthalamic nucleus (STN) deep brain stimulation (DBS) is a key treatment for medically refractory Parkinson's disease.
• Accurate localization of the STN is critical for effective DBS surgery.
• Various anatomical and physiological methods exist for STN targeting.

Purpose of the Study:

• To retrospectively compare different anatomical targeting methods for STN localization.
• To evaluate the accuracy of these methods against the final physiological target determined by microelectrode recording.
• To identify the optimal targeting strategy for STN DBS.

Main Methods:

• Compared four targeting methods: MRI-based, atlas-based, indirect midcommissural point, and a composite method.
• Analyzed x, y, and z coordinates for 30 STN targets in 15 patients undergoing bilateral STN DBS.
• Final physiological targets were determined via single-cell microelectrode recording.

Main Results:

• All anatomical methods showed statistically significant differences from physiological targets (P < 0.001).
• The composite method had the smallest average distance error (1.3 +/- 1.1 mm) compared to MRI (2.6 +/- 1.3 mm), atlas (1.7 +/- 1.1 mm), and midcommissural (1.5 +/- 0.8 mm).
• Direct MRI targeting was the least accurate method.

Conclusions:

• While all tested anatomical methods offer STN localization, a combined approach yields the best correlation with the physiological target.
• The composite targeting method, integrating MRI, atlas, and indirect localization, is recommended for precise STN DBS surgery.
• Refined targeting on one side improved accuracy for the contralateral side.