Metabolic Changes Induced by Electrical Stimulation of Prelemniscal Radiations for the Treatment of Parkinson Disease.
OBJECTIVE
The aim of this work was to study mechanisms of action of electrical stimulation of prelemniscal radiations (Raprl) in the treatment of Parkinson disease, using 2-deoxy-2-fluoro-D-glucose (18F-FDG) Positron Emission Tomography (PET/CT). Materialand Methods: Five patients with PD and predominant unilateral tremor, rigidity and bradykinesia underwent deep brain stimulation (DBS) in contralateral Raprl that improved symptoms from 82.4 to 94.5%. 18F-FDG PET studies were performed before electrode implantation and after DBS therapy. Changes in metabolic activity in PET were evaluated by the maximal standardized uptake value (MSUV) and statistical parametric mapping (SPM) for regions of interest (ROIs) ipsilateral and contralateral to the stimulation site. ROIs were derived from a preoperative probabilistic tractography and included primary motor, supplementary motor and orbitofrontal cortices: Raprl, ventrolateral thalamus, putamen and cerebellum.


RESULTS
No significant MSUV changes occurred in ROIs contralateral to Raprl-DBS. In contrast, MSUV decreased ipsilateral to DBS in Raprl, the thalamus, and the primary and supplementary motor cortices. SPM analysis showed metabolic changes which were significantly different after DBS therapy in all ROIs ipsilateral to DBS compared to those in the contralateral side.


CONCLUSIONS
Raprl-DBS decreases the metabolic activity of areas anatomically related to its fiber composition. Improvement of symptoms may result from a decrease in pathological overactivity of circuits related to the ROIs.
Unit for Stereotactic, Functional Neurosurgery and Radiosurgery, Mexico General Hospital, Mexico City, Mexico.
Francisco
F
Velasco
Sara
S
Llanos
Miguel A
MA
Avila-Rodriguez
Arturo
A
Avendaño-Estrada
Julián
J
Soto
Luis
L
Concha
María Guadalupe
MG
García Gomar
José D
JD
Carrillo-Ruiz
D000328:Adult; D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D046690:Deep Brain Stimulation / Q000379:methods; D005260:Female; D006801:Humans; D018476:Hypokinesia / Q000000981:diagnostic imaging / Q000378:metabolism / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000000981:diagnostic imaging / Q000378:metabolism / Q000628:therapy*; D011877:Radionuclide Imaging; D016896:Treatment Outcome; D014202:Tremor / Q000000981:diagnostic imaging / Q000378:metabolism / Q000628:therapy*