Focused Ultrasound Thalamotomy for Essential Tremor in the Setting of a Ventricular Shunt: Technical Report.

Journal: Operative Neurosurgery (Hagerstown, Md.)
Published:
Abstract

Background: A recent randomized controlled trial of magnetic resonance imaging (MRI)-guided focused ultrasound (FUS) for essential tremor (ET) demonstrated safety and efficacy. Patients with ventricular shunts may be good candidates for FUS to minimize hardware-associated infections.

Objective: To demonstrate feasibility of FUS in this subset of patients.

Methods: A 74-yr-old male with medically refractory ET, and a right-sided ventricular shunt for normal pressure hydrocephalus, underwent FUS to the right ventro-intermedius (VIM) nucleus. The VIM nucleus was directly targeted using deterministic tractography. Clinical outcomes were measured using the Clinical Rating Scale for Tremor.

Results: Shunt components required 6% of the total ultrasound transducer elements to be shut off. Eight therapeutic sonications were delivered (maximum temperature, 64°), leading to a 90% improvement in hand tremor and a 100% improvement in functional disability at the 3-mo follow-up. No complications were noted.

Conclusion: This is the first case of FUS thalamotomy in a patient with a shunt. Direct VIM targeting and achievement of therapeutic temperatures with acoustic energy is feasible in this subset of patients.

Authors
Andrew Yang, Hanane Chaibainou, Sumei Wang, Frederick Hitti, Brendan Mcshane, David Tilden, Matthew Korn, Aaron Blanke, Mor Dayan, Ronald Wolf, Gordon Baltuch