Probabilistic Lesion Mapping to Optimize Thalamotomy Targets for Focal Hand Dystonia

Area of Science:

• Neurosurgery
• Neurology
• Movement Disorders

Background:

• Focal hand dystonia (FHD) significantly impairs motor control.
• Optimal surgical targets for FHD stereotactic intervention remain unclear.

Purpose of the Study:

• Identify the precise thalamic lesion site for symptomatic FHD improvement.
• Clarify the network connectivity of the optimal surgical target.

Main Methods:

• Retrospective analysis of 164 FHD patients undergoing stereotactic thalamotomy.
• Voxel-wise probabilistic lesion mapping to correlate lesion location with outcomes.
• Structural connectivity analyses of fiber tracts linked to the lesion site.

Main Results:

• Lesioning the Vop-Vim border zone significantly improved FHD symptoms.
• The predictive model demonstrated high accuracy (AUC=0.836) in validation.
• Vop-Vim border connectivity involves cerebellothalamic and pallidothalamic pathways.

Conclusions:

• Targeting the Vop-Vim border optimizes clinical benefit and minimizes adverse effects in FHD thalamotomy.
• Establishes the first evidence-based thalamic target for FHD.
• Provides practical guidance for stereotactic interventions and advances dystonia pathophysiology understanding.