Connectomic Basis for Tremor Control in Stereotactic Radiosurgical Thalamotomy

Area of Science:

• Neuroscience
• Radiosurgery
• Biomarkers

Background:

• Stereotactic radiosurgical thalamotomy is increasingly used for tremor.
• New biomarkers are needed to predict treatment outcomes.
• Current methods lack precision for guiding ablative therapies.

Purpose of the Study:

• To investigate if a
• connectome fingerprint
• derived from resting-state fMRI and MR tractography can predict tremor improvement after stereotactic radiosurgical thalamotomy.
• To assess the potential of these fingerprints as targeting biomarkers for personalized treatment.

Main Methods:

• 27 patients with essential tremor or Parkinson disease underwent unilateral stereotactic radiosurgical thalamotomy.
• Pre-treatment resting-state fMRI and MR tractography were used to generate whole-brain connectivity maps (R-maps).
• Leave-one-out cross-validation was employed to assess the predictive accuracy of the connectivity fingerprints.

Main Results:

• Mean tremor improvement was 55.1% post-treatment.
• Structural connectivity (r=0.52, P=.006) and functional connectivity (r=0.50, P=.008) significantly correlated with tremor reduction.
• Connectivity patterns in the cerebello-thalamo-cortical pathway and visual cortices were associated with better outcomes.

Conclusions:

• Distinct connectivity profiles, or "connectomic fingerprints," can predict tremor improvement following stereotactic radiosurgical thalamotomy.
• These findings suggest that connectomic fingerprints hold promise as patient-specific biomarkers for guiding radiosurgical thalamotomy.
• Personalized biomarker development could enhance the efficacy of ablative therapies for tremor disorders.