Chronic deep brain stimulation for the treatment of tremor in multiple sclerosis: review and case reports.
BACKGROUND
Deep brain stimulation (DBS) offers a non-ablative alternative to thalamotomy for the surgical treatment of medically refractory tremor in multiple sclerosis. However, relatively few outcomes have been reported.


OBJECTIVE
To provide a systematic review of the published cases of DBS use in multiple sclerosis and to present four additional patients.


METHODS
Quantitative and qualitative review of the published reports and description of a case series from one centre.


RESULTS
In the majority of reported cases (n=75), the surgical target for DBS implantation was the ventrointeromedial nucleus of the thalamus. Tremor reduction and improvement in daily functioning were achieved in most patients, with 87.7% experiencing at least some sustained improvement in tremor control postsurgery. Effects on daily functioning were less consistently assessed across studies; in papers reporting relevant data, 76.0% of patients experienced improvement in daily functioning. Adverse effects were similar to those reported for DBS in other patient populations.


CONCLUSIONS
Few of the studies reviewed used highly standardised quantitative outcome measures, and follow up periods were generally one year or less. Nonetheless, the data suggest that chronic DBS often produces improved tremor control in multiple sclerosis. Complete cessation of tremor is not necessarily achieved, there are cases in which tremor control decreases over time, and frequent reprogramming appears to be necessary.
Wishart
H A
HA
Department of Psychiatry, Dartmouth Medical School, Lebanon, New Hampshire 03756-0001, USA. heather.wishart@dartmouth.edu
Roberts
D W
DW
Roth
R M
RM
McDonald
B C
BC
Coffey
D J
DJ
Mamourian
A C
AC
Hartley
C
C
Flashman
L A
LA
Fadul
C E
CE
Saykin
A J
AJ
D000328:Adult; D004599:Electric Stimulation Therapy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000628:therapy*; D012189:Retrospective Studies; D013788:Thalamus / Q000502:physiology*; D016896:Treatment Outcome