Predictors of Outcomes After Focused Ultrasound Thalamotomy

Area of Science:

• Neurosurgery
• Neurology
• Medical Technology

Background:

• Magnetic resonance-guided focused ultrasound thalamotomy (FUS-T) is an emerging treatment for essential tremor (ET).
• Essential tremor is a neurological condition characterized by involuntary shaking.
• FUS-T offers a non-invasive therapeutic option for medication-refractory ET.

Purpose of the Study:

• To identify predictors of treatment outcomes following FUS-T for essential tremor.
• To compare outcomes between pivotal and postpivotal trial groups.
• To analyze the relationship between operative parameters and tremor reduction.

Main Methods:

• Analysis of 179 patients with medication-refractory essential tremor undergoing unilateral FUS-T.
• Comparison of outcomes between pivotal (2013-2015) and postpivotal (2015-2016) trial groups.
• Assessment of tremor scores and disability ratings at multiple time points post-procedure, with statistical adjustment for confounding variables.

Main Results:

• Patient age, disease duration, peak temperature, and number of sonications were significant predictors of tremor outcomes.
• The postpivotal group demonstrated greater improvement in hand tremor scores at 12 months (61.9% vs 52.1%, P=.009).
• Higher peak temperatures were achieved in the postpivotal group (56.7°C vs 55.6°C, P=.004), correlating with improved outcomes after adjustment.

Conclusions:

• Outcomes improved in the postpivotal group compared to the pivotal group, suggesting a potential learning curve in FUS-T application.
• Key predictors for successful FUS-T in essential tremor include patient age, disease duration, peak temperature, and the number of sonications.
• FUS-T is a viable treatment for essential tremor, with procedural parameters and patient factors influencing efficacy.