Individual fiber anatomy of the subthalamic region revealed with diffusion tensor imaging: a concept to identify the deep brain stimulation target for tremor suppression.
BACKGROUND
Deep brain stimulation (DBS) has been proven to alleviate tremor of various origins. Distinct regions have been targeted. One explanation for good clinical tremor control might be the involvement of the dentatorubrothalamic tract (DRT) as has been suggested in superficial (thalamic) and inferior (posterior subthalamic) target regions. Beyond a correlation with atlas data and the postmortem evaluation of patients treated with lesion surgery, proof for the involvement of DRT in tremor reduction in the living, the scope of this work, is elusive.


OBJECTIVE
To report a case of unilateral refractory tremor in tremor-dominant Parkinson disease treated with thalamic DBS.


METHODS
Preoperative diffusion tensor imaging (DTI) was performed. Correlation with individual DBS electrode contact locations was obtained through postoperative fusion of helical computed tomography (CT) data with DTI fiber tracking.


RESULTS
Tremor was alleviated effectively. An evaluation of the active electrode contact position revealed clear involvement of the DRT in tremor control. A closer evaluation of clinical effects and side effects revealed a highly detailed individual fiber map of the subthalamic region with DTI fiber tracking.


CONCLUSIONS
This is the first time the involvement of the DRT in tremor reduction through DBS has been shown in the living. The combination of DTI with postoperative CT and the evaluation of the electrophysiological environment of distinct electrode contacts led to an individual detailed fiber map and might be extrapolated to refined DTI-based targeting strategies in the future. Data acquisition for a larger study group is the topic of our ongoing research.
Division of Stereotaxy and MR-Based Operative Techniques/Department of Neurosurgery, Bonn University, Bonn, Germany. volker.coenen@ukb.uni-bonn.de
Volker A
VA
Coenen
Burkhard
B
Mädler
Hagen
H
Schiffbauer
Horst
H
Urbach
Niels
N
Allert
D000368:Aged; D046690:Deep Brain Stimulation / Q000295:instrumentation / Q000379:methods*; D056324:Diffusion Tensor Imaging / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D008297:Male; D010300:Parkinson Disease / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy; D011182:Postoperative Care / Q000295:instrumentation / Q000379:methods; D011712:Pyramidal Tracts / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000502:physiology; D020530:Subthalamus / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods; D014202:Tremor / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*