Objectives: In recent years, there has been a growing amount of evidence tying Essential Tremor (ET) to cerebellar dysfunction. This has been clinically observed, demonstrated through specific gait measures of ataxia (often involving tandem gait), and confirmed through Positron emission tomography (PET) imaging. Deep Brain stimulation for ET has become a widely utilized therapeutic intervention for patients, and the bilateral thalamic ventralis intermedius (VIM) is most commonly implanted. However, it has been noted that in some patients gait ataxia significantly worsens post-op. This initially was thought to be a result of disease progression, but recent studies have in fact shown that this is a DBS related phenomenon.
Methods: Participants will have two visits to either the Portland VA or Oregon Health \& Science University (OHSU). At each visit, several assessments of balance, tremor, gait and balance, and DBS settings will be made. The gait and balance assessments will be performed by a unblinded and a blinded rater.
