BACKGROUND: Severe forms of dystonia respond poorly to medical treatment. Deep-brain stimulation is a reversible neurosurgical procedure that has been used for the treatment of dystonia, but assessment of its efficacy has been limited to open studies. METHODS: We performed a prospective, controlled, multicenter study assessing the efficacy and safety of bilateral pallidal stimulation in 22 patients with primary generalized dystonia. The severity of dystonia was evaluated before surgery and 3, 6, and 12 months postoperatively during neurostimulation, with the use of the movement and disability subscores of the Burke-Fahn-Marsden Dystonia Scale (range, 0 to 120 and 0 to 30, respectively, with higher scores indicating greater impairment). Movement scores were assessed by a review of videotaped sessions performed by an observer who was unaware of treatment status. At three months, patients underwent a double-blind evaluation in the presence and absence of neurostimulation. We also assessed the patients' quality of life, cognition, and mood at baseline and 12 months. RESULTS: The dystonia movement score improved from a mean (+/-SD) of 46.3+/-21.3 before surgery to 21.0+/-14.1 at 12 months (P<0.001). The disability score improved from 11.6+/-5.5 before surgery to 6.5+/-4.9 at 12 months (P<0.001). General health and physical functioning were significantly improved at month 12; there were no significant changes in measures of mood and cognition. At the three-month evaluation, dystonia movement scores were significantly better with neurostimulation than without neurostimulation (24.6+/-17.7 vs. 34.6+/-12.3, P<0.001). There were five adverse events (in three patients); all resolved without permanent sequelae. CONCLUSIONS: These findings support the efficacy and safety of the use of bilateral stimulation of the internal globus pallidus in selected patients with primary generalized dystonia.

https://www.nejm.org/doi/pdf/10.1056/NEJMoa042187

Bilateral Deep-Brain Stimulation of the Globus Pallidus in Primary Generalized Dystonia

Deep brain stimulation (DBS) has provided remarkable benefits for people with a variety of neurologic conditions. Stimulation of the ventral intermediate nucleus of the thalamus can dramatically relieve tremor associated with essential tremor or Parkinson disease (PD). Similarly, stimulation of the subthalamic nucleus or the internal segment of the globus pallidus can substantially reduce bradykinesia, rigidity, tremor, and gait difficulties in people with PD. Multiple groups are attempting to extend this mode of treatment to other conditions. Yet, the precise mechanism of action of DBS remains uncertain. Such studies have importance that extends beyond clinical therapeutics. Investigations of the mechanisms of action of DBS have the potential to clarify fundamental issues such as the functional anatomy of selected brain circuits and the relationship between activity in those circuits and behavior. Although we review relevant clinical issues, we emphasize the importance of current and future investigations on these topics.

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Deep Brain Stimulation

Deep brain stimulation (DBS) has provided remarkable therapeutic benefits for people with a variety of neurological disorders. Despite the uncertainty of the precise mechanisms underlying its efficacy, DBS is clinically effective in improving motor function of essential tremor, Parkinson's disease and primary dystonia and in relieving obsessive-compulsive disorder. Recently, this surgical technique has continued to expand to other numerous neurological diseases with encouraging results. This review highlighted the current and potential future clinical applications of DBS.

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Deep brain stimulation.

Pharmacological relief of neuropathic pain is often insufficient. Electrical neurostimulation is efficacious in chronic neuropathic pain and other neurological diseases. European Federation of Neurological Societies (EFNS) launched a Task Force to evaluate the evidence for these techniques and to produce relevant recommendations. We searched the literature from 1968 to 2006, looking for neurostimulation in neuropathic pain conditions, and classified the trials according to the EFNS scheme of evidence for therapeutic interventions. Spinal cord stimulation (SCS) is efficacious in failed back surgery syndrome (FBSS) and complex regional pain syndrome (CRPS) type I (level B recommendation). High-frequency transcutaneous electrical nerve stimulation (TENS) may be better than placebo (level C) although worse than electro-acupuncture (level B). One kind of repetitive transcranial magnetic stimulation (rTMS) has transient efficacy in central and peripheral neuropathic pains (level B). Motor cortex stimulation (MCS) is efficacious in central post-stroke and facial pain (level C). Deep brain stimulation (DBS) should only be performed in experienced centres. Evidence for implanted peripheral stimulations is inadequate. TENS and r-TMS are non-invasive and suitable as preliminary or add-on therapies. Further controlled trials are warranted for SCS in conditions other than failed back surgery syndrome and CRPS and for MCS and DBS in general. These chronically implanted techniques provide satisfactory pain relief in many patients, including those resistant to medication or other means.

/pdf/efns-guidelines-on-neurostimulation-therapy-for-neuropathic-25ss0yu4oj.pdf

EFNS guidelines on neurostimulation therapy for neuropathic pain

Parkinson’s disease is a chronic progressive neurodegenerative disorder characterized by resting tremor, slowness of movements, rigidity, gait disturbance and postural instability. Most investigations on Parkinson’s disease focused on the basal ganglia, whereas the cerebellum has often been overlooked. However, increasing evidence suggests that the cerebellum may have certain roles in the pathophysiology of Parkinson’s disease. Anatomical studies identified reciprocal connections between the basal ganglia and cerebellum. There are Parkinson’s disease–related pathological changes in the cerebellum. Functional or morphological modulations in the cerebellum were detected related to akinesia/rigidity, tremor, gait disturbance, dyskinesia and some non-motor symptoms. It is likely that the major roles of the cerebellum in Parkinson’s disease include pathological and compensatory effects. Pathological changes in the cerebellum might be induced by dopaminergic degeneration, abnormal drives from the basal ganglia and dopaminergic treatment, and may account for some clinical symptoms in Parkinson’s disease. The compensatory effect may help maintain better motor and non-motor functions. The cerebellum is also a potential target for some parkinsonian symptoms. Our knowledge about the roles of the cerebellum in Parkinson’s disease remains limited, and further attention to the cerebellum is warranted.

The cerebellum in Parkinson’s disease

Object Writer's cramp is a type of idiopathic focal hand dystonia characterized by muscle cramps that accompany execution of the writing task specifically. In this report, the authors describe the clinical outcome after thalamic deep brain stimulation (DBS) therapy in patients with writer's cramp and present an illustrative case with which they compare the effects of pallidal and thalamic stimulation. In addition to these results for the clinical effectiveness, they also examine the best point and pattern for therapeutic stimulation of the motor thalamus, including the nucleus ventrooralis (VO) and the ventralis intermedius nucleus (VIM), for writer's cramp. Methods The authors applied thalamic DBS in five patients with writer's cramp. The inclusion criteria for the DBS trial in this disorder were a diagnosis of idiopathic writer's cramp and the absence of a positive response to medication. The exclusion criteria included significant cognitive dysfunction, active psychiatric symptoms, and evidence of othe...

Thalamic deep brain stimulation for writer's cramp.

The effects of spinal cord stimulation (SCS), deep brain stimulation (DBS) of the thalamic nucleus ventralis caudalis (VC) and motor cortex stimulation (MCS) were analyzed in 19 patients with phantom limb pain All of the patients underwent SCS and, if the SCS failed to reduce the pain, the patients were considered for DBS and/or MCS Satisfactory pain control for the long-term was achieved in 6 of 19 (32%) by SCS, 6 of 10 (60%) by DBS and 1 (20%) of 5 by MCS SCS and DBS of the VC sometimes produced a dramatic effect on the pain, leading to a long pain-free interval and infrequent use of stimulation The effects of both DBS of the VC and MCS were tested in four One patient of them reported better pain control by MCS than by DBS, whereas two reported the opposite results There is no evidence at present for an advantage of MCS over SCS and DBS of the VC in controlling phantom limb pain

Motor cortex stimulation for phantom limb pain: comprehensive therapy with spinal cord and thalamic stimulation.

We analyzed the effects of spinal cord stimulation (SCS), deep brain stimulation (DBS) of the thalamic nucleus ventralis caudalis (VC) and motor cortex stimulation (MCS) in 45 patients with post-stroke pain. Satisfactory pain control was obtained more frequently as the stimulation site was moved to higher levels (7% by SCS, 25% by DBS and 48% by MCS). A painful sensation was sometimes produced by stimulation of the VC as well as the post-central, pre-central and pre-frontal cortices. Such a sensation occurred less frequently as the stimulation site was moved to higher levels (50% at the VC, 39% at the post-central cortex, 6% at the pre-central cortex and 3% at the pre-frontal cortex). These findings imply that abnormal processing of nociceptive information develops at the level of deafferentation and spreads to higher levels to a varying extent. This may be one of the reasons why satisfactory pain control was obtained more frequently as the stimulation site was moved to higher levels.

Motor cortex stimulation for post-stroke pain: comparison of spinal cord and thalamic stimulation.

One hundred and seven patients in vegetative state (VS) were evaluated neurologically and electrophysiologically over 3 months (90 days) after the onset of brain injury. Among these patients, 21 were treated with deep brain stimulation (DBS). The stimulation sites were the mesencephalic reticular formation (two patients) and centromedian-parafascicularis nucleus complex (19 cases). Eight of the patients recovered from VS and were able to obey verbal commands at 13 and 10 months in the case of head trauma and at 19, 14, 13, 12, 12 and 8 months in the case of vascular disease after comatose brain injury, and no patients without DBS recovered from VS spontaneously within 24 months after brain injury. The eight patients who recovered from VS showed desynchronization on continuous EEG frequency analysis. The Vth wave of the auditory brainstem response and N20 of the somatosensory evoked potential could be recorded, although with a prolonged latency, and the pain-related P250 was recorded with an amplitude of > 7 μV. Sixteen (14.9%) of the 107 VS patients satisfied these criteria in our electrophysiological evaluation, 10 of whom were treated with DBS and six of whom were not treated with DBS. In these 16 patients, the recovery rate from VS was different between the DBS therapy group and the no DBS therapy group (P < 0.01, Fisher's exact probability test) These findings indicate that DBS may be useful for the recovery of patients from VS if the candidates are selected on the basis of electrophysiological criteria.

Deep brain stimulation for the treatment of vegetative state

Object. The tremor-suppression effect resulting from long-term stimulation of the thalamic nucleus ventralis intermedius (Vim) and the nucleus ventralis oralis posterior (Vop) was examined in the treatment of parkinsonian, essential, and poststroke tremor. Methods. After identifying the accurate anterior border of the nucleus ventrocaudalis (Vc), deep brain stimulation (DBS) electrodes with four contacts were inserted into the Vim—Vop region at an angle of between 40 and 50° from the horizontal plane of the anterior commissure—posterior commissure line. Two distal contacts were placed on the Vim side and two proximal contacts on the Vop side. The best sites of stimulation and parameters of bipolar stimulation were selected in each case and follow-up examinations were conducted for at least 2 years. In all 15 cases of parkinsonian tremor (18 sides) and in 14 of 15 cases of essential tremor (24 of 25 sides), cathodal stimulation of the Vim side with anodal stimulation of the Vop side was determined to be th...

Deep brain stimulation for the treatment of parkinsonian, essential, and poststroke tremor: a suitable stimulation method and changes in effective stimulation intensity

Kazutaka Kobayashi

Papers

Thalamic deep brain stimulation for writer's cramp.

Motor cortex stimulation for phantom limb pain: comprehensive therapy with spinal cord and thalamic stimulation.

Motor cortex stimulation for post-stroke pain: comparison of spinal cord and thalamic stimulation.

Deep brain stimulation for the treatment of vegetative state

Deep brain stimulation for the treatment of parkinsonian, essential, and poststroke tremor: a suitable stimulation method and changes in effective stimulation intensity