Subthalamic nucleus or internal pallidal stimulation in young onset Parkinson’s disease
1. Brain. 1998 Mar;121 ( Pt 3):451-7. doi: 10.1093/brain/121.3.451.
Subthalamic nucleus or internal pallidal stimulation in young onset Parkinson’s
disease.
Krack P(1), Pollak P, Limousin P, Hoffmann D, Xie J, Benazzouz A, Benabid AL.
Author information:
(1)Department of Clinical and Biological Neurosciences, Joseph Fourier
University of Grenoble, France.
The aim of this study was to compare, retrospectively, the value of chronic
bilateral stimulation of the internal globus pallidus (GPi) and the subthalamic
nucleus (STN) in patients with young onset Parkinson’s disease. We selected 13
consecutive patients with similar characteristics at the time of surgery: age at
onset < 40 years, disabling motor fluctuations (Hoehn and Yahr stage 4 or 5 in
off-drug phases) and levodopa-induced dyskinesias (LID). Eight patients were
operated on in the STN and five in the GPi. The Unified Parkinson's Disease
Rating Scale (UPDRS), timed motor tests and a LID scale were compared in on- and
off-drug conditions before surgery and 6 months after surgery on stimulation
using the chronic electrical parameters found to improve best the motor state of
the individual patient, without adverse effects. In off-drug phases, the motor
score of the UPDRS was improved by 71% with STN stimulation and by 39% with GPi
stimulation on average. This difference was statistically significant (P <
0.05). Whereas rigidity and tremor showed good improvement in both groups, the
decrease in the akinesia score was more pronounced in the STN group. In the STN
group, the improvement of all motor symptoms was very close, or equal, to the
best levodopa response. Thus the levodopa test was predictive of outcome. The
improvement in off-drug period motor handicap allowed a decrease in the
levodopa-equivalent dose only in the STN group (-56%). The voltage, frequency
and pulse width used for chronic stimulation were lower in the STN group. In the
on-drug phases there was a marked improvement in LID in the GPi group, as
measured by the dyskinesias score during an acute levodopa test, whereas there
was only a small decrease in the STN group (P < 0.05). However, in the long
term, the reduction of levodopa dosage in the STN group led to an indirect
reduction of LID similar to that in the GPi group during activities of everyday
life. In conclusion, the overall results favour the neurosurgical treatment of
Parkinson's disease by stimulating the STN rather than the GPi.
DOI: 10.1093/brain/121.3.451
PMID: 9549521 [Indexed for MEDLINE]