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category=Deep brain stimulation|
developer=NeuroPace, Inc. Mountain View, California|
developer_commentary=<ref name="neuropacecompany">NeuroPace. Company Overview. NeuroPace, Inc. [online]. © 2016. Available online at: http://www.neuropace.com/about-us-corporate/ (Retrieved 4.11.2016).</ref>|
announced=December, 2009 |
announced_commentary=<ref name="newsmedical">NOVELLI, P. NeuroPace announces clinical trial results demonstrating the RNS System. News medical life sciences [online]. 2009, Dec 9. Available online at: http://www.news-medical.net/news/20091209/NeuroPace-announces-clinical-trial-results-demonstrating-the-RNS-System.aspx (Retrieved 4.11.2016).</ref><ref> Pivotal Trial Data Demonstrate NeuroPace RNS® System Reduced Seizures in People with Epilepsy. NeuroPace, Inc. [online]. © 2016. Available online at: http://www.neuropace.com/pivotal-trial-data-demonstrate-neuropace/ (Retrieved 4.11.2016).</ref>|
developer_release=|
developer_release_commentary=|
consumers_release_commentary=|
price=35,000|
price_commentary=(estimated)<ref name="USCNews">TRINIDAD, T. Keck Medicine physicians first to implant epilepsy-controlling device. USC News [online]. 2013, Dec 19. Available online at: https://news.usc.edu/57947/keck-medicine-physicians-become-first-to-implant-epilepsy-controlling-device/ (Retrieved 4.11.2016).</ref> |
max_output=11.5 mA|
max_output_commentary=± 10%, at 500 Ohms; <ref name="NeuropaceSystemUserManual>NeuroPace. RNS® System User Manual. NeuroPace, Inc. [online]. © 2016. Available online at: http://www.neuropace.com/wp-content/uploads/2016/08/RNS_System_User_Manual.pdf (Retrieved 4.11.2016).</ref>|
max_session_duration=5|
max_session_duration_commentary=(min 10 msec)<ref name="NeuropaceSystemUserManual"/>|
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RNS® System (hereinafter referred to as RNS System) is medical device for epilepsy treatment.<ref name="neuropaceAbout_the_technology">NeuroPace. About the technology. NeuroPace, Inc. [online]. © 2016. Available online at: http://www.neuropace.com/the-rns-system/ (Retrieved 4.11.2016).</ref> It can monitor and stimulate brain activity, for it is [[Deep brain stimulation|deep brain stimulation]] device. It is manufactured by privately held company named NeuroPace, which is located in Montain View, California.<ref name="BusinessWirePhoenixConference">NeuroPace RNS® System Honored With Prestigious Award At The 22nd Annual Phoenix Conference. Business Wire: A Berkshire Hathaway Company [online]. 2015, Nov 4. Available online at: http://www.businesswire.com/news/home/20151104005381/en/NeuroPace-RNS%C2%AESystem-Honored-Prestigious-Award-22nd (Retrieved 4.11.2016).</ref> The therapy with RNS System consists in reducing the frequency of seizures in individuals<ref name="NeuropaceSystemUserManual"/>, who have partial-onset, medically refractory (drug resistant) epilepsy.<ref name="NCBI">THOMAS, G.P., JOBST, B.C. Critical review of the responsive neurostimulator system for epilepsy. The National Center for Biotechnology Information [online]. 2015, Oct 1. Available online at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4598207/ (Retrieved 4.11.2016).</ref> Those patients are treated with the RNS System, when they have no more than two epileptogenic foci (epileptogenic focus is the source or starting point of the seizures) and are resistant to more than two antiepileptic medications. The RNS System is thus only for medical prescription.
== Main characteristics ==
Plain device consist of:
* RNS Neurostimulator, which is a responsive electrical stimulation medical device (battery powered and microprocessor controlled) <ref name="NeuropaceSystemUserManual"/> Responsive electrical stimulation is a new approach to treat epilepsy and RNS System is the first device to provide it. <ref name="epilepsyResponsiveNeurostimulation>SIRVEN, J.I. Responsive Neurostimulation. Epilepsy Foundation [online]. 2014, May. Available online at: http://www.epilepsy.com/learn/treating-seizures-and-epilepsy/devices/responsive-neurostimulation (Retrieved 4.11.2016).</ref> RNS Neurostimulator indicates and records certain patterns in the brain (electrocoticographic, ECoG patterns), which causes seizures. Then delivers short trains of current pulses through the leads to interrupt those patterns. Each stimulation can contain two bursts. Neurstimulator must be implanted in the skull together with leads.<ref name="NeuropaceSystemUserManual"/> The Neurostimulator should work for about 2 to 3.5 years, before battery power is drained. It is size of 28 x 60 mm, so it is relatively small device.<ref name="NeuropaceSystemPatientManual">NeuroPace. NeuroPace® RNS® System Patient Manual. NeuroPace, Inc [online]. © 2016. Available online at: http://www.accessdata.fda.gov/cdrh_docs/pdf10/P100026C.pdf (Retrieved 4.11.2016).</ref>
* NeuroPace Leads are placed in the brain and are connected to Neurostimulator. One lead contains four electrodes. There are two kind of these leads. First, the Cortical Strip Leads are intended to subdural implant and are available in 15, 25 or 35 centimetres length. Four electrodes in leads are spaced 10 millimetres apart from each other. Second, the Depth Leads are intended for implant into brain. They are in four combinations - 30 centimetre length, 10 millimetre electrode spacing; 30 centimetre length, 3.5 millimetre electrode spacing; 44 centimetre length, 10 millimetre electrode spacing or 44 centimetre length, 3.5 millimetre electrode spacing.<ref name="NeuropaceSystemUserManual"/>
'''Enhancement'''
The RNS System is medical device to treat epilepsy. It is not designed for enhancing human capabilities, although it was demonstrated, that the RNS System has no adverse cognitive effect in epileptics. <ref name="BusinessWirePositiveEffects">NeuroPace RNS® System Associated with Positive Effects In Memory and Language for People Living with Partial Onset Epilepsy. Business Wire: A Berkshire Hathaway Company [online]. 2015, Oct 20. Available online at: http://www.businesswire.com/news/home/20151020005454/en/NeuroPace-RNS%C2%AE-System-Positive-Effects-Memory-Language (Retrieved 4.11.2016).</ref> In several cases it even comes to some improvements in the cognitive capabilities. Although these findings are inconclusive for they result from very various data.<ref name="AES_ResponsiveNeurostimulation_and_Cognition">SPENCER, D. Responsive Neurostimulation and Cognition. Epilepsy Currents [online]. 2016, March-April, Vol. 16, No. 2, pp. 98-100. Available online at: http://www.epilepsycurrents.org/doi/full/10.5698/1535-7511-16.2.98 (Retrieved 4.11.2016).</ref> A possible explanation of the alleged cognitive enhancement may rest in reduced seizures. But this is not enhancement of the sort, but rather "side effect" of the successful treatment of epilepsy.
'''Epilepsy'''
Epilepsy or “seizure disorder” is a chronic disorder, which causes unpredictable seizures of all kinds, which might have all sorts of other consequences. Epilepsy usually has not simple or known cause.<ref name="epilepsyWhatIsEpilepsy">SIRVEN, J.I. What Is Epilepsy? Epilepsy Foundation [online]. 2014, Jan. Available online at: http://www.epilepsy.com/learn/epilepsy-101/what-epilepsy (Retrieved 4.11.2016).</ref> It might be caused some illness (for example brain tumors or Alzheimer’s disease<ref name="NIH_The_Epilepsies_and_Seizures">National Institute of Neurological Disorders and Stroke. The Epilepsies and Seizures. National Institute of Neurological Disorders and Stroke [online]. 2015, Aug, NIH Publication No. 15-156. Available online at: http://www.ninds.nih.gov/disorders/epilepsy/curing_the_epilepsies_brochure.pdf (Retrieved 4.11.2016).</ref>, brain damage, abnormal brain development, genetic mutation (de novo mutations) etc..<ref name="NIH_The_Epilepsies_and_Seizures"/> But those causes might be very diverse. Epilepsy always arises from brain and is bound to sudden abnormal brain electrical activity.<ref name="NIH_The_Epilepsies_and_Seizures"/> Clusters of neurons might fire signal faster than normal, which is as many as 500 times a second. That electric activity then causes seizure.<ref name="NIH_The_Epilepsies_and_Seizures"/> This medical condition is considered, when individual has at least two or more unprovoked seizures separated by 24 hours.<ref name="NIH_The_Epilepsies_and_Seizures"/> In the United States suffer from epilepsies up to 2.3 million adults and more than 450,000 children. <ref name="NIH_The_Epilepsies_and_Seizures"/> Without satisfactory seizure control still remain 15-40% of all patients.<ref name="Neurostimulation for the Treatment of Epilepsy">Wu C., Sharan A.D. 2012. Neurostimulation for the Treatment of Epilepsy: A Review of Current Surgical Interventions. Neuromodulation 2012; e-pub ahead of print. DOI: 10.1111/j.1525-1403.2012.00501.x</ref>
There are many possible triggers of seizures in epilepsy.<ref name="NIH_The_Epilepsies_and_Seizures"/> The most common perceived triggers are: missing medication (40.9%), emotional stress (31.3%), sleep deprivation (19.7%), fatigue (15.3%), missing meals (9.1%), fever (6.4%), and smoking (6.4%). Data was obtained form 405 patients.<ref name="Perceived trigger factors of seizures in persons with epilepsy">BALAMURUGAN, et al. Perceived trigger factors of seizures in persons with epilepsy. Elsevier Inc., 2013, Vol. 33, Iss. 9, pp 743 - 747. Available online at: http://www.seizure-journal.com/article/S1059-1311(13)00177-5/pdf (Retrieved 4.11.2016).</ref> Only around 3% of epileptics have a photosensitive epilepsy. That is the kind of epilepsy, which is triggered by certain visual patterns, such as flashing lights.<ref name="Photosensitivity and Seizures">SHAFER, P.O., SIRVEN, J.I. Photosensitivity and Seizures. Epilepsy foundation [online]. 2013, Nov. Available online at: http://www.epilepsy.com/learn/triggers-seizures/photosensitivity-and-seizures (Retrieved 5.12.2016).</ref> There are more than 30 different types of seizures, but generally they are divided into the two major groups – the focal seizures, which originate only in one part of the brain, and the generalized seizures, which come from both sides of the brain.<ref name="NIH_The_Epilepsies_and_Seizures"/> These seizures might look very different, they might or might not cause loss of consciousness, or a muscle´s massive contractions. It might also appear, for example in the intense feeling of déjà vu. Epilepsy has also many various types, for example the absence epilepsy, the frontal lobe epilepsy, the temporal lobe epilepsy (most common form in focal seizures) or the neocortical epilepsy.<ref name="NIH_The_Epilepsies_and_Seizures"/>
Epilepsy has also some risks associated with the life-threatening conditions, such as "status epilepticus" and "sudden unexpected death". However these cases are relatively rare. More common risks are appearing in connection with the injury during seizures.<ref name="NIH_The_Epilepsies_and_Seizures"/>
There are several possible scenarios with regard to the treatment of epilepsy. Epilepsy might be treated with medications (for example, Carbamezepine, Diazepam, Lorazepam, Topiramate etc.), diet (a hight-fat, very low carbonhydrate ketogenic diet), surgery (only if focal seizures persist after at least two medications or if it is identifiable brain lesions) or devices just like the RNS System. There are some different possible devices to treat epilepsy, for instance, the Vagus nerve stimulator (approved by the FDA in 1997) or the experimental devices not approved by the FDA: the trigeminal nerve stimulation or the transcutaneous magnetic stimulation.<ref name="NIH_The_Epilepsies_and_Seizures"/>
The treatment with the RNS System provides responsive cortical stimulation via neurostimulator connected to depth or subdural cortical strip leads. They are placed in the brain based on seizure focus. The neurostimulator continually scans electrocorticographic activity, detects abnormal activity and provides stimulation. The physician regulates and optimizes the parameters for each patient individually.<ref name="MorrellResponsive cortical stimulation">MORRELL, M.J. Responsive cortical stimulation for the treatment of medically intractable partial epilepsy. Neurology. Neurology, 2011, Sep 27, vol. 77, no. 13, pp. 1275-1304. ISSN 0028-3878. </ref> It always depends upon where in the brain is the focus of epilepsy. Seizures might come from different cortical location, that include temporal, frontal, centroparietal, or occipital lobe regions. <ref name="epilepsyFamilial Focal Epilepsy">PANAYIOTOPOULOS, C.P. Familial Focal Epilepsy with Variable Foci. Epilepsy Foundation [online]. 2005, Jan. Available online at: http://www.epilepsy.com/information/professionals/about-epilepsy-seizures/familial-autosomal-dominant-focal-epilepsies-2 (Retrieved 4.11.2016).</ref> But the RNS System is adjusted only for at the most two foci of seizures.<ref name="NeuropaceSystemUserManual"/>
So the treatment with the help of the RNS System is not intended for everyone. The patient must fulfil several conditions: he must have the focal (partial)<ref>According to International League Against Epilepsy (ILAE) is the concept of “partial” replaced by “focal” to unified terminology of epilepsies</ref> seizures, has average three or more disabling seizures per month (over the three most recent month), and he has to be resistant to the medications or diet (drug resistant is in the case of RNS System defined according to ILAE as a failure to control seizures after two seizures medications).
The implanted devices also might negatively interact with another medical procedures, such as Computed Tomography or MR (magnetic resonance).<ref name="NeuropaceSystemPatientManual"/> It might also cause allergic reaction, skin erosion (around the Neurostimulator), lead migration (move from their desired implant location) etc. There always remains a risk of failure the RNS devices.<ref name="NeuropaceSystemPatientManual"/>
Serious risk might also come from unknown effect of long-term brain stimulation.<ref name="NeuropaceSystemPatientManual"/> This conclusion supports as well the study conducted by Loring, Kapur, Meador and Morrell.<ref name="Differential neuropsychological outcomes following targeted responsive neurostimulation for partial-onset epilepsy">LORING, D.W., KAPUR, R., MEADOR, K.J., MORRELL, M.J. Differential neuropsychological outcomes following targeted responsive neurostimulation for partial-onset epilepsy. Epilepsia [online], 2015, Vol. 56, No. 11, pp. 1836–1844. Available online at: http://onlinelibrary.wiley.com/doi/10.1111/epi.13191/epdf (Retrieved 6.11.2016).</ref> It is probably too soon to determine exact effect of the brain stimulation. The study for long time effect of the brain stimulation is still under way and the estimated completion date is May 2023. <ref name="RNS® System Epilepsy PAS">RNS® System Epilepsy PAS. ClinicalTrials.gov [online]. 2016, Sep. Available online at: https://clinicaltrials.gov/ct2/show/results/NCT02403843 (Retrieved 6.11.2016).</ref>
* Benefits
So it is clear that the RNS System is risky, but at the same time it helps people with epilepsy to reduce seizures. It still does not help every patient with epilepsy, because the RNS System is designed only to certain type of the epileptic condition. However according to Thomas and Jobst the RNS System might not be so effective in seizure reduction as epilepsy surgery.<ref name="NCBI"/> On the other hand, epilepsy surgery is not always appropriate for certain type of epileptic illness. The RNS System thus remains suitable alternative to treat epilepsy. Similar conclusion also supports The University of Southern California (USC) Neurorestoration Centre and the Keck Hospital of USC, that are the world's first institutions to implant the RNS System post FDA approval. They confirm that:
''"The RNS System can be readily incorporated into an active epilepsy surgical center."''<ref name="A Single-Center Experience with the NeuroPace RNS System">LEE, B., ZUBAIR, M.N., MARQUEZ, Y.D., LEE, D.M., KALAYJIAN, L.A., HECK, C.N., LIU, C.Y. A Single-Center Experience with the NeuroPace RNS System: A Review of Techniques and Potential Problems. Elsevier Inc., 2015, Vol. 84, Iss. 3, pp. 719 - 726. Available online at: http://www.worldneurosurgery.org/article/S1878-8750(15)00479-9/references (Retrieved 7.11.2016).</ref>
'''Ethical Issues'''
Some danger might arise also from hacker´s attack. The device interacts with the programmer, which is possible to replicate and then operate the Neurostimulator. But according to Frank Fisher, the CEO of the NeuroPace, it is very unlikely due to the fact, that it is significantly difficult and there is neither a reason for someone to do that, because the hacker has in theory only two options. One option is that he might do something with the device, so it was not function any more. Or he might deliver several inappropriate stimulation and cause a seizure.<ref name="NeuroPace: Controlling Epilepsy With a Brain Implant">NeuroPace: Controlling Epilepsy With a Brain Implant. Interview with Frank Fischer, the CEO of NeuroPace, Inc. IEEE Spectrum [online]. 2013, Nov 5. Available online at: http://spectrum.ieee.org/podcast/biomedical/bionics/neuropace-controlling-epilepsy-with-a-brain-implant (Retrieved 6.11.2016).</ref> These risks should not have been taken lightly, even if they are very unlikely.
In case of the RNS System is required to consider, if benefits outweigh considerable risks. According to FDA, they did. But it depends on each patient individually after all. Some people might have a problem with implementation a device in the brain, because every intervention to the brain is very risky. For some people it might be completely unacceptable that they would have the device in their bodies, for example, based on their beliefs.
There are many successful stories of patients with implanted RNS System. One of the first patient, who received the RNS System outside the study group was Tracey Drake in November 2014 at New York-Presbyterian/Weill Cornell Medical Center. She has reported very positive experience with the RNS System.<ref name="Epilepsy Team Implants First NeuroPace RNS Neurostimulator ">Epilepsy Team Implants First NeuroPace RNS Neurostimulator. Weill Cornell Brain and Spine Center [online]. 2014, Nov 7. Available online at: http://weillcornellbrainandspine.org/in-the-news/epilepsy-team-implants-first-neuropace-rns-neurostimulator (Retrieved 6.11.2016)</ref> There are several similar stories that show positive effects of the RNS System.
For example Ian Olsen, who suffers from epilepsy since 11 years old, says about RNS System this: ''After dealing with seizures for 16 years, I feel like I have now defeated my seizures once and for all. The RNS system is helping more and more people with epilepsy – and everyone battling seizures should know about it.''<ref name="NeuroPace_stories">NeuroPace. Ian’s Story. NeuroPace, Inc. [online]. © 2016. Available online at: http://www.neuropace.com/ians-story/ (Retrieved 30.11.2016).</ref>
Now is also especially necessary to establish exactly which role the RNS System will play in treatment of epilepsy. In fact, the RNS System is still at the beginning and it is perceived more like alternative to AED (antiepileptic drug) or surgery. <ref name="AES_ResponsiveNeurostimulation_and_Cognition"/> There remains a question how will look the RNS System in the future. Frank Fischer note that:
== Public Policy ==
The RNS System was approved (Premarket Approval, PMA) by Food and Drug Administration (FDA) in 2013 based on clinical studies. Those contain a Feasibility study, a Pivotal study, and a Long-term Treatment study. There were also several studies in laboratory, where were tested every single device of the RNS System. Before human studies, there were also studies on animals, particularly on sheep. The Feasibility study contained 65 subjects and was aimed at preliminary safety and effectiveness. The results of the Feasibility study was used in the Pivotal study, which was performed ''"to establish a reasonable assurance of safety and effectiveness of the RNS System"''. It was containing 191 subjects in total. The Long-term Treatment study is still ongoing. It contains 230 subjects. <ref name="SSFD">U.S. Food & Drug Administration. Summary of Safety and Effectiveness Data (SSED). U.S. Food & Drug Administration [online]. 2013. Available online at: http://www.accessdata.fda.gov/cdrh_docs/pdf10/P100026B.pdf (Retrieved 4.11.2016).</ref>
The RNS System devices are connected with several patents. On the website of the NeuroPace company, there are list of the patents for every single device of RNS System: NeuroPace® RNS® Neurostimulator, NeuroPace® Depth Lead, NeuroPace® Cortical Strip Lead, NeuroPace® Programmer, NeuroPace® Remote Monitor, Wand and Ferrule.<ref name="NeuroPace_patents">NeuroPace. Legal Terms. NeuroPace, Inc. [online]. © 2016. Available online at: http://www.neuropace.com/legal/ (Retrieved 30.11.2016).</ref>
== Related Technologies, Projects or Scientific Research ==
[[File:Vns cyberonics.jpg|thumb|Vagus Nerve Stimulation (VNS)]]
VNS, manufactured by Cyberonics, Inc.<ref name="Premarket Approval (VNS Therapy System)">U.S. Food & Drug Administration. Premarket Approval (VNS Therapy System). U.S. Food & Drug Administration [online]. 2016. Available online at: http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpma/pma.cfm?id=P970003 (Retrieved 6.12.2016).</ref>, sends regular, mild pules of electrical energy to the brain via the vagus nerve. It is placed under the skin in the chest and in the neck.<ref name="VNS">SCHACHTER, S.C., SIRVEN, J.I. Vagus Nerve Stimulation (VNS). Epilepsy foundation [online]. 2013. Available online at: http://www.epilepsy.com/learn/treating-seizures-and-epilepsy/devices/vagus-nerve-stimulation-vns (Retrieved 2.12.2016).</ref> VNS began clinical investigation in 1988 and was approved by FDA (Premarket Approval) for the treatment of medically refractory epilepsy in 1997. VNS is intended to treat epilespy of partial-onset seizures. But recent studies have suggested to treat with VNS other epilepsy syndromes, such as idiopthic generalized epilepsies and Lennox-Gestaut syndrome. Efficacy of VNS in the seizures reduction is ranging between 35 - 50%. It always depend on the particularly study. VNS has been associated with positive improvement of alertness and mood. The negative side effects are connected with acute phase after implantation (intermittent hoarseness (28%), cough (14%), voice alteration (13%), paresthesias (12%), headache (4.5%), and shortness of breath (3.2%)).<ref name="Neurostimulation for the Treatment of Epilepsy"/>
TNS is not yet been approved by FDA. It has been studied in animal and pilot clinical trials. But it has not yet been sufficiently corroborated, that TNS is effective to treat epilepsy, based on relatively small scale of the trials.<ref name="Trigeminal Nerve Stimulation May Not Be Effective">PACK, A.M. Trigeminal Nerve Stimulation May Not Be Effective for the Treatment of Refractory Partial Seizures. Epilepsy Currents. 2013, Vol. 13, No. 4, pp. 164–165.</ref>
DBS treatment is stimulation of the different areas of central nervous system. Most extensively has been studied the stimulation of the anterior nucleus of the thalamus. The DBS stimulation has been approved first by European Union (Conformité Européenne, CE) for company Medtronic in 2013 <ref name="Medtronic Receives European CE Mark Approval">Medtronic. Medtronic Receives European CE Mark Approval for Deep Brain Stimulation Therapy for Refractory Epilepsy. Medtronic, Inc. [online]. 2010. Available online at: http://newsroom.medtronic.com/phoenix.zhtml?c=251324&p=irol-newsArticle&ID=1773303 (Retrieved 5.12.2016).</ref>, and than by FDA in 2013 for treatment of epilepsy (under the FDAs Humanitarian Device Exception)<ref name="Deep Brain Stimulation: Expanding Applications">TEKRIWAL, A., BALTUCH, G. Deep Brain Stimulation: Expanding Applications. Neurol Med Chir, Tokyo, 2015, Vol. 55, No. 12, pp. 861–877.</ref>. The other areas of the stimulation are, for example the cerebellum or the hippocampus. Effectiveness of the stimulation in the anterior nucleus is estimated on 50% reduction seizures.<ref name="Neurostimulation for the Treatment of Epilepsy"/>
The RNS System is on the other hand based on closed-loop stimulation, which provide stimulation only if triggered by early seizure activity. However the above mentioned systems of stimulation provide stimulation constantly, regardless of neuronal activity. So the RNS System has less adverse effect than the rest.<ref name="Neurostimulation for the Treatment of Epilepsy"/>
There are also some similar devices, that treat the different kind of diseases. One of them is, for example the [[Activa]] Deep Brain Stimulation Therapy System (Medtronic), which is target to treat tremor associated with Parkinson´s disease and essential tremor. It was approved by FDA in 1997.<ref name=" FDA Okays Brio">JEFFREY, S. FDA Okays Brio Neurostimulation System for PD, ET. Medscape [online]. 2015, Jun 12. Available online at: http://www.medscape.com/viewarticle/846456 (Retrieved 3.12.2016).</ref> Similar device for reducing the symptoms of Parkinson's disease is the [[Brio™ Rechargeable IPG]], which was approved by FDA in 2015.<ref name="FDA approves brain implant to help reduce Parkinson’s disease">U.S. Food & Drug Administration. FDA approves brain implant to help reduce Parkinson’s disease and essential tremor symptoms. U.S. Food & Drug Administration: FDA News Release [online]. 2015, Jun 12. Available online at: http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm451152.htm (Retrieved 3.12.2016).</ref>
== References ==
