Distance between Active Electrode Contacts and Dentatorubrothalamic Tract in Patients with Habituation of Stimulation Effect of Deep Brain Stimulation in Essential Tremor.
BackgroundSome patients under thalamic deep brain stimulation (DBS) for essential tremor (ET) experience habituation of tremor reduction. The nucleus ventralis intermedius (Vim) is the current main target side for ET in DBS. However, the dentatorubrothalamic tract (DRTT) is considered the relevant structure to stimulate. We investigated the distance between the active contact of the DBS electrode and the DRTT and compared this distance in patients with habituation of tremor reduction and good responders.Material and MethodsIn this retrospective study, we performed deterministic fiber tracking of the DRTT in 6 patients (12 hemispheres) with ET who underwent DBS in the Vim. We subsequently measured the distance between the active contact of the electrode and the ipsilateral DRTT in both hemispheres. The clinical tremor response of those 6 patients was analyzed accordingly.ResultsThe distance between the active contact and the DRTT in patients with better and constant clinical tremor reduction was shorter (mean distance: 2.9 ± 2.2 mm standard deviation [SD]) than in patients who showed habituation of their response (mean distance: 6.1 ± 3.9 mm SD). After re-placement of a thalamic electrode inside the DRTT in one patient who experienced unsatisfying tremor reduction due to habituation of stimulation, the tremor alleviation was significant and persistent at a 13-month follow-up.ConclusionThis retrospective analysis suggests that recurrence of ET tremor under chronic DBS might be associated with a larger distance between the DRTT and the active lead contact, in comparison with the smaller distances in patients with persistently good tremor control.
Department of Neurosurgery, Universitatsklinikum Regensburg Klinik und Poliklinik fur Neurochirurgie Ringgold Standard Institution, Regensburg, Germany.
Judith Maria
JM
Anthofer
Department of Neurosurgery, Universitatsklinikum Regensburg Klinik und Poliklinik fur Neurochirurgie Ringgold Standard Institution, Regensburg, Germany.
Kathrin
K
Steib
Department of Neurosurgery, University Medical Center Regensburg, Regensburg, Germany.
Max
M
Lange
Department of Neurology, Universitatsklinikum Regensburg Klinik und Poliklinik fur Neurologie Ringgold Standard Institution, Regensburg, Bayern, Germany.
Eva
E
Rothenfusser
Department of Radiology, University Hospital Regensburg, Regensburg, Germany.
Claudia
C
Fellner
Department of Neurosurgery, University Medical Center Regensburg, Regensburg, Germany.
Alexander
A
Brawanski
Department of Neurosurgery, Universitatsklinikum Regensburg Klinik und Poliklinik fur Neurochirurgie Ringgold Standard Institution, Regensburg, Germany.
Juergen
J
Schlaier
D000368:Aged; D002529:Cerebellar Nuclei / Q000601:surgery*; D046690:Deep Brain Stimulation; D004567:Electrodes, Implanted; D020329:Essential Tremor / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012012:Red Nucleus / Q000601:surgery*; D012189:Retrospective Studies; D013787:Thalamic Nuclei / Q000601:surgery*