Regulatory Framework for Implantable Neurostimulation Devices: Comparison of Systems in the US and European Union.

Background: Implantable neurostimulation devices must be authorized before they are placed on the market. For this purpose, requirements, and processes for assessing their fulfillment, have been defined in different jurisdictions.

Objective: In this study, we aimed to address differences between the US and European Union (EU) regulatory systems and their relationship to innovation.

Targeting of the Subthalamic Nucleus for Deep Brain Stimulation: A Survey Among Parkinson Disease Specialists.

Background: Deep brain stimulation within or adjacent to the subthalamic nucleus (STN) represents the most common stereotactic procedure performed for Parkinson disease. Better STN imaging is often regarded as a requirement for improving stereotactic targeting. However, it is unclear whether there is consensus about the optimal target.

Multiple-source current steering in subthalamic nucleus deep brain stimulation for Parkinson's disease (the VANTAGE study): a non-randomised, prospective, multicentre, open-label study.

Background: High-frequency deep brain stimulation (DBS) with a single electrical source is effective for motor symptom relief in patients with Parkinson's disease. We postulated that a multiple-source, constant-current device that permits well defined distribution of current would lead to motor improvement in patients with Parkinson's disease.

Methods: We did a prospective, multicentre, non-randomised, open-label intervention study of an implantable DBS device (the VANTAGE study) at six specialist DBS centres at universities in six European countries.

Oscillatory subthalamic nucleus activity is modulated by dopamine during emotional processing in Parkinson's disease.

Dopaminergic denervation in Parkinson's disease (PD) leads to motor deficits but also depression, lack of motivation and apathy. These symptoms can be reversed by dopaminergic treatment, which may even lead to an increased hedonic tone in some patients with PD. Here, we tested the effects of dopamine on emotional processing as indexed by changes in local field potential (LFP) activity of the subthalamic nucleus (STN) in 28 PD patients undergoing deep brain stimulation.

Usability of therapy controllers in elderly patients with deep brain stimulation.

Background: Technical devices are becoming more prevalent in society and also in medical care. Older adults need more support to learn new technologies than younger subjects. So far, no research has been done on the usability of patient controllers in deep brain stimulation in an elderly population.

Aging and technology in medical care: using the example of patient controllers in deep brain stimulation.

Deep brain stimulation is a neurosurgical therapy for patients with advanced movement disorders (e.g., Parkinson's disease).

Predictability of thermo-lesions using electrodes for deep brain stimulation - an in vitro study.

Background: Typically, electrodes for Deep Brain Stimulation (DBS) are used for chronic stimulation. However, there are conditions where this therapy has to be discontinued. In such cases using the DBS electrodes as a tool for thermo-lesioning (coagulation) could be used for an alternative treatment.

Technical analysis of dual channel pulse generators used in deep brain stimulation; a safety evaluation.

Background: A sudden failure of implantable pulse generators (IPG) occurred in 15 out of 143 units during the last 4 years in our patients. This corresponds to a failure rate of 10.5%.

Long-term effects of STN DBS on mood: psychosocial profiles remain stable in a 3-year follow-up.

Background: Deep brain stimulation of the subthalamic nucleus significantly improves motor function in patients with severe Parkinson's disease. However, the effects on nonmotor aspects remain uncertain. The present study investigated the effects of subthalamic nucleus deep brain stimulation on mood and psychosocial functions in 33 patients with advanced Parkinson's disease in a three year follow-up.

Subacute brainstem angioencephalopathy: favorable outcome with anticoagulation therapy.

We present a patient who developed progressive neurological disease caused by lesions histologically compatible with those observed in subacute brainstem angioencephalopathy. The patient was treated with low-molecular weight heparin, and treatment response was monitored clinically and with MRI. Anticoagulation therapy stopped progression of the neurological deficit and led to improvement of MRI findings.

Deep brain pulse-generator and lead-extensions: subjective sensations related to measured parameters.

This study analyzed subjective sensations caused by DBS pulse-generator and lead-extensions in relation with objectively measured parameters. In 50 patients implant-related sensations were evaluated. The pulse-generator mobility was video-analyzed.

Sudden failure of implantable pulse generators: cause of failure and examination.

A sudden failure of implantable pulse generators used for spinal cord stimulation occurred in two patients. To identify the cause of this failure, an intensive destructive analysis of the explanted devices was carried out. A functional diagnosis was carried out by inspecting amplitude, pulse width and frequency on each output channel of the implantable pulse generators.

Frequency-correlated decreases of motor cortex activity associated with subthalamic nucleus stimulation in Parkinson's disease.

According to the classical model of basal ganglia organization, deep brain stimulation (DBS) in the subthalamic nucleus (STN) for the treatment of Parkinson's disease (PD) blocks overactive excitatory projections to inhibitory basal ganglia output structures. This would release the break on thalamofrontal neurons alleviating the poverty of movement, the hallmark of PD. Such parallels to a functional lesion certainly simplify the mechanism of STN DBS.

Efficient internal pallidal stimulation in Gilles de la Tourette syndrome: a case report.

The usefulness of deep brain stimulation (DBS) of thalamic nuclei in Gilles de la Tourette syndrome (GTS) has recently been advocated. We report on a 14-month follow-up study of a patient with intractable GTS in whom bilateral DBS of the internal globus pallidus was carried out. Tic frequency per minute decreased by 73% in the postoperative phase and in particular the vocal tics became less intense.

Sudden failure of dual channel pulse generators.

We report a series of four sudden hardware failures in dual channel pulse generators implanted for chronic stimulation of the subthalamic nucleus in the treatment of Parkinson's disease. In all cases, a sudden and severe deterioration of the patient's neurological condition occurred with symptoms similar to those present before surgery. In all cases, destructive analysis of the generator revealed a fracture of the wire bonds connecting the battery to the hybrid (electronic) part of the pulse generator.

Postoperative monitoring of the electrical properties of tissue and electrodes in deep brain stimulation.

The aim of this study was to investigate the causation of an insufficient clinical response to acute external stimulation after implantation of brain stimulating electrodes in patients with idiopathic Parkinson's disease (IPD). This study represents to our knowledge the first consecutive postoperative monitoring of the electrical properties of electrodes and tissue in this patient cohort. We hypothesized that changes in brain tissue resistance would be etiologic for this clinically observed phenomenon.

Dielectric properties of porcine brain tissue in the transition from life to death at frequencies from 800 to 1900 MHz.

Ten experiments on pigs were performed to investigate possible postmortem changes of the dielectric properties of brain gray matter in the frequency range of 800-1900 MHz. After keeping the animals in stable anaesthesia for at least 45 min, they were euthanatised by an intravenous injection of hypertonic potassium chloride (KCl), causing cardiac arrest within 3 min. Measurements of the dielectric properties were performed repeatedly from at least 45 min prior to death to 18 h after euthanasia.

Electromagnetic interference of GSM mobile phones with the implantable deep brain stimulator, ITREL-III.

Background: The purpose was to investigate mobile phone interference with implantable deep brain stimulators by means of 10 different 900 Mega Hertz (MHz) and 10 different 1800 MHz GSM (Global System for Mobile Communications) mobile phones.

Methods: All tests were performed in vitro using a phantom especially developed for testing with deep brain stimulators. The phantom was filled with liquid phantom materials simulating brain and muscle tissue.

Chronic thalamic stimulation in a patient with spinocerebellar ataxia type 2.

We report on a patient with spinocerebellar ataxia type 2 (SCA 2) with an unusual clinical presentation, including severe, disabling resting and action tremor and the successful treatment of this tremor syndrome with chronic thalamic stimulation. Using [(123)I]beta-CIT single photon emission computed tomography, we document a marked degeneration of the nigrostriatal dopaminergic system in SCA 2.

Temperature measurement on neurological pulse generators during MR scans.

According to manufacturers of both magnetic resonance imaging (MRI) machines, and implantable neurological pulse generators (IPGs), MRI is contraindicated for patients with IPGs. A major argument for this restriction is the risk to induce heat in the leads due to the electromagnetic field, which could be dangerous for the surrounding brain parenchyma. The temperature change on the surface of the case of an ITREL-III (Medtronic Inc.