Low Frequency Deep Brain Stimulation for Dystonia: Lower is Not Always Better

• Main Authors: Frances M. Velez-Lago, Genko Oyama, Kelly D. Foote, Nelson Hwynn, Pamela Zeilman, Charles Jacobson, Samuel Wu, Michael S. Okun
• Format: Article
• Language: English
• Published: Ubiquity Press 2012-02-01
• Series: Tremor and Other Hyperkinetic Movements
• Online Access: https://tremorjournal.org/index.php/tremor/article/view/55

<p><strong>Background:</strong>&nbsp; It has been observed that low-frequency stimulation (LFS) may be effective for dystonia, and the use of LFS may alleviate the need for frequent battery changes in a subset of patients. The aim of this study was to analyze LFS as a strategy to treat deep brain stimulation (DBS) patients with various dystonias.</p> <p><strong>Methods:&nbsp;</strong>Subjects had to receive a minimum of 6 months of clinical follow-up at the University of Florida, and were required to have a minimum of 3 months on a LFS trial. Twenty-seven dystonia DBS patients were retrospectively analyzed from the UF-INFORM database.</p><p><strong>Results: </strong>Thirteen subjects met inclusion criteria. Of the 13 subjects, all had bilateral internal pallidum (GPi) DBS, and five (38.5%) remained with at least one side on LFS settings at their last follow up (average follow up 24 months, range 6&ndash;46 months). Within the first 6 months, six (46%) subjects remained on LFS and seven (54%) were changed to high-frequency stimulation (HFS). Those who remained on LFS settings at 6 months were characterized by shorter disease durations than those on HFS settings. There were no significant differences in dystonia severity (Unified Dystonia Rating Scale and Burke&ndash;Fahn&ndash;Marsden Dystonia Rating Scale) at baseline between the two settings. The estimated battery life for LFS (79.9&plusmn;30.5) was significantly longer than for HFS settings (32.2&plusmn;13.1, p&lt;0.001)</p> <p><strong>Discussion: </strong>LFS was ultimately chosen for 38.5% of all subjects. Although this study failed to yield solid predictive features, subjects on LFS tended to have shorter disease durations.</p>