Thalamotomy as a Treatment Option for Tremor after Ineffective Deep Brain Stimulation

Background: As the number of deep brain stimulation (DBS) surgeries increases, complications from malpositioned electrodes, tolerance to stimulation and loss of efficacy have also increased. Our objective was to assess thalamotomy as a salvage treatment option after ineffective DBS. Methods: A retrospective chart analysis of patients who underwent ipsilateral stereotactic thalamotomy after an ineffective ventrointermediate nucleus DBS procedure was undertaken. Patient outcome was based on follow-up visit chart notes, and a nonvalidated patient telephone questionnaire to assess patients' perception of tremor and functional ability after thalamotomy. Results: Six patients with essential tremor and 1 with tremor-predominant Parkinson's disease met our inclusion criteria. Thalamotomies were undertaken for ineffective DBS due to dysarthria and paresthesias with programming in 2 patients, tremor that failed to respond to increased DBS despite a lack of side effects in 2 patients, malpositioned electrode in 2 patients, and sudden loss of DBS efficacy following eye surgery in 1 patient. Following thalamotomy, 3 patients reported improvement in symptoms and function, 3 patients reported improvement in symptoms that were not reflected in functional improvement, and 1 patient reported no improvement in symptoms or function. Conclusion: Thalamotomy may provide a viable salvage solution in patients who fail to respond to DBS due to complications such as malpositioned electrodes, tolerance to stimulation or loss of efficacy.