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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 centimenters centimetres length. Four electrodes in leads are spaced 10 millimenters millimetres apart from each other. Second, the Depth Leads are intended for implant into brain. They are in four combinations - 30 centimeter centimetre length, 10 millimeter millimetre electrode spacing; 30 centimeter centimetre length, 3.5 millimeter millimetre electrode spacing; 44 centimeter centimetre length, 10 millimeter millimetre electrode spacing or 44 centimeter centimetre length, 3.5 millimeter millimetre electrode spacing.<ref name="NeuropaceSystemUserManual"/>
* NeuroPace components and accessories contain several devices, for example cranial prosthesis or magnet, which might be used as suppressor of therapy or starter an electrocorticogram storage (records ECoG patterns), if it is placed over the implanted RNS Neurostimulator.<ref name="NeuropaceSystemUserManual"/>
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 patinetspatients.<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 relativelly relatively rare. More common risks are appearing in connection with the injury during seizures.<ref name="NIH_The_Epilepsies_and_Seizures"/>
'''Treatment'''
''“Given the available information above'' [clinical studies], ''the data support that for the following indications for use the probable benefits outweigh the probable risks.”''<ref name="NeuropaceSystemPatientManual"/>
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 Center 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 delivere deliver several inappropriate stimulation and cause a seizure.<ref name="NeuroPace: Controlling Epilepsy With a Brain Implant">NeuroPace: Controlling Epilepsy With a Brain Implant. Interwiev 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.
== Related Technologies, Projects or Scientific Research ==
There exist several possible treatement treatment for epilepsy on the basis of deep brain stimulation: vagus nerve stimulation (VNS), trigeminal nerve stimulation (TNS), deep brain stimulation (DBS), and closed-loop stimulation system (RNS System).<ref name="Neurostimulation for the Treatment of Epilepsy"/>
[[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 epilespies epilepsies and Lennox-Gestaut syndrome. Efficacy of VNS in the sizures seizures reduction is ranging between 35 - 50%. It always depend on the particulary 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 approven 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 relativelly 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 meantioned 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 targget 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 Neurostimulation System[[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 ==
