Post-Traumatic Tremor and Thalamic Deep Brain Stimulation: Evidence for Use of Diffusion Tensor Imaging.
BACKGROUND
Deep brain stimulation (DBS) is a well-established treatment to reduce tremor, notably in Parkinson disease. DBS may also be effective in post-traumatic tremor, one of the most common movement disorders caused by head injury. However, the cohorts of patients often have multiple lesions that may impact the outcome depending on which fiber tracts are affected.


METHODS
A 20-year-old man presented after road traffic accident with severe closed head injury and polytrauma. Computed tomography scan showed left frontal and basal ganglia hemorrhagic contusions and intraventricular hemorrhage. A disabling tremor evolved in step with motor recovery. Despite high-intensity signals in the intended thalamic target, a visual analysis of the preoperative diffusion tensor imaging revealed preservation of connectivity of the intended target, ventralis oralis posterior thalamic nucleus (VOP). This was confirmed by the postoperative tractography study presented here. DBS of the VOP/zona incerta was performed. Six months postimplant, marked improvement of action (postural, kinetic, and intention) tremor was achieved.


CONCLUSIONS
We demonstrated a strong connectivity between the VOP and the superior frontal gyrus containing the premotor cortex and other central brain areas responsible for movement control. In spite of an existing lesion in the target, the preservation of these tracts may be relevant to the improvement of the patient's symptoms by DBS.
Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, Oxford, United Kingdom. Electronic address: sandra.boccard@ndcn.ox.ac.uk.
Sandra G J
SG
Boccard
Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, Oxford, United Kingdom.
Pedro
P
Rebelo
Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, Oxford, United Kingdom.
Binith
B
Cheeran
Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, Oxford, United Kingdom.
Alexander
A
Green
Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, Oxford, United Kingdom.
James J
JJ
FitzGerald
Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, Oxford, United Kingdom.
Tipu Z
TZ
Aziz
D046690:Deep Brain Stimulation / Q000379:methods*; D038524:Diffusion Magnetic Resonance Imaging; D005500:Follow-Up Studies; D016489:Head Injuries, Closed / Q000150:complications* / Q000175:diagnosis / Q000628:therapy*; D006801:Humans; D020198:Intracranial Hemorrhage, Traumatic / Q000150:complications* / Q000175:diagnosis / Q000628:therapy; D008297:Male; D009415:Nerve Net / Q000503:physiopathology; D014057:Tomography, X-Ray Computed; D014202:Tremor / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy*; D020651:Ventral Thalamic Nuclei / Q000503:physiopathology*; D055815:Young Adult
Deep brain stimulation; Post-traumatic tremor; Thalamus; Tractography; VOP