Subthalamic neuron activity related to tremor and movement in Parkinson's disease (original) (raw)

Neurophysiological identification of the subthalamic nucleus in surgery for Parkinson's disease

Annals of Neurology, 1998

Microelectrode recording methods for stereotactic localization of the subthalamic nucleus (STN) and surrounding structures are described. These methods accurately define targets for chronic deep brain stimulation in the treatment of Parkinson's disease. Mean firing rates and a burst index were determined for all recorded neurons, and responses to active and passive limb and orofacial movements were tested. STN neurons had a mean firing rate of 37 ± 17 Hz (n = 248) and an irregular firing pattern (median burst index, 3.3). Movement-related activity and tremor cells were identified in the STN. Ventral to the STN, substantia nigra pars reticulata neurons had a mean rate of 71 ± 23 Hz (n = 56) and a more regular firing pattern (median burst index, 1.7). Short trains (1–2 seconds) of electrical microstimulation of STN could produce tremor arrest but were and found to be useful for localization. Compared with data from normal monkeys our findings suggest that STN neuronal activity is elevated in Parkinson's disease.

Stimulation of the Subthalamic Nucleus in a Patient With Parkinson Disease and Essential Tremor

Archives of Neurology, 2005

Background: The preferred surgical target for the treatment of Parkinson disease (PD) is either the internal globus pallidus or the subthalamic nucleus (STN); the target for treatment of essential tremor (ET) is the thalamic subnucleus ventralis intermedius (Vim). Some patients with PD have coexistent ET, and the identification of a single surgical target to treat both parkinsonian motor symptoms and ET would be of practical importance. Objective: To describe the use of the STN target in deep brain stimulator (DBS) surgery to treat PD motor symptoms and the action-postural tremor of ET.

The effects of brain stimulation of subthalamic nucleus surgery on gait and balance performance in Parkinson disease

Archives of Medical Science, 2012

A b s t r a c t I In nt tr ro od du uc ct ti io on n: : Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by tremor, rigidity and bradykinesia. Gait and postural difficulties supersede tremor, rigidity and bradykinesia as drivers of disease burden in patients with advanced PD. The aim of this study was to describe the effects of deep brain stimulation of the subthalamic nucleus on gait ability and balance performance in patients with PD. M Ma at te er ri ia al l a an nd d m me et th ho od ds s: : We studied 19 consecutive patients who underwent bilateral stimulation of the subthalamic nucleus. Patients were evaluated preoperatively and at the 5 th day and 6 th month after surgery. Timed Up and Go Test, 12 m Walking Test, Chair Stand Test and Berg Balance Scale (BBS) were used to assess mobility and balance performance. Unified Parkinson's Disease Rating Scale (UPDRS III) and Hoehn and Yahr Scale were also used. R Re es su ul lt ts s: : All the patients' mobility ability and balance performance improved after surgery (p < 0.05). At the 6 th month after surgery, the Timed Up and Go Test scores were decreased from 56.05 ±42.52 to 21.47 ±20.36, the 12 m Walking Test scores were decreased from 100.44 ±66.44 to 28.84 ±19.79, the Chair Stand Test scores were increased from 4.00 ±4.66 to 11.68 ±4.43 and the BBS score was increased from 12.84 ±6.89 to 38.89 ±8.79. UPDRS total scores were significantly improved 6 months after surgery (p < 0.001). UPDRS total scores were decreased from 98.26 ±37.69 to 39.36 ±18.85. The Hoehn and Yahr Scale score was significantly decreased after surgery (p < 0.05). C Co on nc cl lu us si io on ns s: : Surgical therapy is an effective treatment to improve gait ability and balance performance in Parkinson's patients.

Effects of subthalamic nucleus stimulation and medication on resting and postural tremor in Parkinson's disease

Brain, 2004

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) and antiparkinsonian medication have proved to be effective treatments for tremor in Parkinson's disease. To date it is not known how and to what extent STN DBS alone and in combination with antiparkinsonian medication alters the pathophysiology of resting and postural tremor in idiopathic Parkinson's disease. The purpose of this study was to examine the effects of STN DBS and antiparkinsonian medication on the neurophysiological characteristics of resting and postural hand tremor in Parkinson's disease. Resting and postural hand tremor were recorded using accelerometry and surface electromyography (EMG) from 10 Parkinson's disease patients and 10 matched control subjects. The Parkinson's disease subjects were examined under four treatment conditions: (i) off treatment; (ii) STN DBS; (iii) medication; and (iv) medication plus STN DBS. The amplitude, EMG frequency, regularity, and 1-8 Hz tremor-EMG coherence were analysed. Both STN DBS and medication reduced the amplitude, regularity and tremor-EMG coherence, and increased the EMG frequency of resting and postural tremor in Parkinson's disease. STN DBS was more effective than medication in reducing the amplitude and increasing the frequency of resting and postural tremor to healthy physiological levels. These findings provide strong evidence that effective STN DBS normalizes the amplitude and frequency of tremor. The findings suggest that neural activity in the STN is an important modulator of the neural network(s) responsible for both resting and postural tremor genesis in Parkinson's disease.

The subthalamic nucleus in Parkinson's disease: somatotopic organization and physiological characteristics

Brain, 2001

Single-cell recording of the subthalamic nucleus (STN) was undertaken in 14 patients with Parkinson's disease submitted to surgery. Three hundred and fifty neurones were recorded and assessed for their response to passive and active movements. Thirty-two per cent were activated by passive and active movement of the limbs, oromandibular region and abdominal wall. All neurones with sensorimotor responses were in the dorsolateral region of the STN. Arm-related neurones were lateral (≥14 mm plane) to leg-related neurones, which were found more medially (≤12 mm). Representation of the oromandibular musculature was in the middle of the sensorimotor region (~13 mm plane) and ventral to the arm and leg. Two hundred neurones were adequately isolated for 'off-line' analysis. The mean frequency of discharge was 33 ⍨ 17 Hz (13-117 Hz). Three types of neuronal discharges were distinguished: irregular (60.5%), tonic (24%) and oscillatory (15.5 %). They were statistically differentiated on the basis of their mean firing frequency and the coefficient of variation of the interspike interval. Neurones responding to movement were of the irregular or tonic Abbreviations: CV ϭ coefficient of variation; DBS ϭ deep brain stimulation; GPl ϭ globus pallidus lateralis; GPm ϭ globus pallidus pars medialis; ISI ϭ interspike interval; STN ϭ subthalamic nucleus; SNpr ϭ substantia nigra pars reticulata © Oxford University Press 2001 type, and were found in the dorsolateral region of the STN. Neurones with oscillatory and low frequency activity did not respond to movement and were in the ventral onethird of the nucleus. Thirty-eight tremor-related neurones were recorded. The majority (84%) of these were sensitive to movement and were located in the dorsolateral region of the STN. Cross power analysis (n ⍧ 16) between the rhythmic neuronal activity and tremor in the limbs showed a peak frequency of 5 Hz (4-8 Hz). Neuronal activity of the subtantia nigra pars reticulata was recorded 0.5-3 mm below the STN. Eighty neurones were recorded 'on-line' and 27 were isolated for 'off-line' analysis. A tonic pattern of discharge characterized by a mean firing rate of 71 ⍨ 28 Hz (35-122 Hz) with a mean coefficient of variation of the interspike interval of 0.85 ⍨ 0.29 ms was found. In only three neurones (11%) was there a response to sensorimotor stimulation. The findings of this study indicate that the somatotopic arrangement and electrophysiological features of the STN in Parkinson's disease patients are similar to those found in monkeys.

Subthalamic Stimulation in Parkinson Disease

Archives of neurology, 2003

Background: High-frequency stimulation of the subthalamic nucleus (STN) is an effective treatment for advanced forms of Parkinson disease. Postoperative improvement of motor parkinsonian disability is known to depend on patient selection and surgical targeting. Objective: To determine which clinical and electrophysiological variables evaluated during the operation predict the postoperative clinical outcome of patients with Parkinson disease treated by bilateral high-frequency stimulation of the STN. Methods: Intraoperative clinical and electrophysiological data obtained in 41 patients with Parkinson disease who underwent bilateral implantation of electrodes for STN stimulation were correlated with the improvement in parkinsonian disability assessed 6 months after the operation. Results: The extent of STN neuronal activity recorded along the trajectory of the therapeutic electrode had no effect on the postoperative clinical outcome. The intraoperative improvement in segmental akinesia, but not rigidity, was predictive of the postoperative improvement in parkinsonian motor disability and reduction in daily levodopaequivalent dosage. Parkinsonian motor disability scores assessed after surgery were lower in patients with intraoperative stimulation-induced dyskinesias than in those without stimulation-induced dyskinesias. Conclusion: The improvement of segmental akinesia and the observation of dyskinesias provoked by stimulation during the operation predict the best postoperative effects of bilateral STN stimulation on parkinsonian motor disability.

Long-term results of a multicenter study on subthalamic and pallidal stimulation in Parkinson's disease

Movement Disorders, 2010

We report the 5 to 6 year follow-up of a multicenter study of bilateral subthalamic nucleus (STN) and globus pallidus internus (GPi) deep brain stimulation (DBS) in advanced Parkinson's disease (PD) patients. Thirty-five STN patients and 16 GPi patients were assessed at 5 to 6 years after DBS surgery. Primary outcome measure was the stimulation effect on the motor Unified Parkinson's Disease Rating Scale (UPDRS) assessed with a prospective cross-over double-blind assessment without medications (stimulation was randomly switched on or off). Secondary outcomes were motor UPDRS changes with unblinded assessments in off- and on-medication states with and without stimulation, activities of daily living (ADL), anti-PD medications, and dyskinesias. In double-blind assessment, both STN and GPi DBS were significantly effective in improving the motor UPDRS scores (STN, P < 0.0001, 45.4%; GPi, P = 0.008, 20.0%) compared with off-stimulation, regardless of the sequence of stimulation. In open assessment, both STN- and GPi-DBS significantly improved the off-medication motor UPDRS when compared with before surgery (STN, P < 0.001, 50.5%; GPi, P = 0.002, 35.6%). Dyskinesias and ADL were significantly improved in both groups. Anti-PD medications were significantly reduced only in the STN group. Adverse events were more frequent in the STN group. These results confirm the long-term efficacy of STN and GPi DBS in advanced PD. Although the surgical targets were not randomized, there was a trend to a better outcome of motor signs in the STN-DBS patients and fewer adverse events in the GPi-DBS group. © 2010 Movement Disorder Society