Transcranial magnetic stimulation (TMS), also known as repetitive transcranial magnetic stimulation (rTMS), is a noninvasive form of brain stimulation in which a changing magnetic field is used to cause electric current at a specific area of the brain through electromagnetic induction. An electric pulse generator, or stimulator, is connected to a magnetic coil, which in turn is connected to the scalp. The stimulator generates a changing electric current within the coil which induces a magnetic field; this field then causes a second inductance of inverted electric charge within the brain itself.:3
TMS has shown diagnostic and therapeutic potential in the central nervous system with a wide variety of disease states in neurology and mental health, with research still evolving.
Adverse effects of TMS are rare, and include fainting and seizure. Other potential issues include discomfort, pain, hypomania, cognitive change, hearing loss, and inadvertent current induction in implanted devices such as pacemakers or defibrillators.
TMS is non-invasive, and does not require surgery or electrode implantation. Its use can be divided into diagnostic and therapeutic applications. Effects vary based on frequency and intensity of the magnetic pulse as well as the length of the train, which affects the total number of pulses given. rTMS treatments are now approved by the FDA in the USA and by NICE in the UK for the treatment of depression and are predominantly provided by private clinics.
TMS can be used clinically to measure activity and function of specific brain circuits in humans, most commonly with single or paired magnetic pulses. The most widely accepted use is in measuring the connection between the primary motor cortex of the central nervous system and the peripheral nervous system to evaluate damage related to past or progressive neurologic insult.
Repetitive high frequency TMS (rTMS) has shown diagnostic and therapeutic potential with the central nervous system in a variety of disease states, particularly in the fields of neurology and mental health.
Although TMS is generally regarded as safe, risks are increased for therapeutic rTMS compared to single or paired diagnostic TMS. Adverse effects generally increase with higher frequency stimulation.
The greatest immediate risk from TMS is fainting, though this is uncommon. Seizures have been reported, but are rare. Other adverse effects include short term discomfort, pain, brief episodes of hypomania, cognitive change, hearing loss, impaired working memory, and the induction of electrical currents in implanted devices such as cardiac pacemakers.
During the procedure, a magnetic coil is positioned at the head of the person receiving the treatment using anatomical landmarks on the skull, in particular the inion and nasion. The coil is then connected to a pulse generator, or stimulator, that delivers electric current to the coil.
TMS uses electromagnetic induction to generate an electric current across the scalp and skull. A plastic-enclosed coil of wire is held next to the skull and when activated, produces a magnetic field oriented orthogonal to the plane of the coil. The magnetic field can then be directed to induce an inverted electric current in the brain that activates nearby nerve cells in a manner similar to a current applied superficially at the cortical surface.
The magnetic field is about the same strength as an MRI, and the pulse generally reaches no more than 5 centimeters into the brain, unless using a modified coil and technique for deeper stimulation.
From the BiotSavart law,
it has been shown that a current through a wire generates a magnetic field around that wire. Transcranial magnetic stimulation is achieved by quickly discharging current from a large capacitor into a coil to produce pulsed magnetic fields between 2 and 3 Tesla in strength. Directing the magnetic field pulse at a targeted area in the brain causes a localized electrical current which can then either depolarize or hyperpolarize neurons at that site. The magnetic flux generated by the current causes its own electric field, as explained by the Maxwell-Faraday equation,
This electric field causes a change in transmembrane currents resulting in depolarization or hyperpolarization of neurons, causing them to be more or less excitable, respectively.
Deep TMS can reach up to 6cm into the brain to stimulate deeper layers of the motor cortex, such as that which controls leg motion. The path of this current can be difficult to model because the brain is irregularly shaped with variable internal density and water content, leading to a nonuniform magnetic field strength and conduction throughout its tissues.
The effects of TMS can be divided based on frequency, duration and intensity (amplitude) of stimulation:
Most devices use a coil shaped like a figure-eight to deliver a shallow magnetic field that affects more superficial neurons in the brain. Differences in magnetic coil design should be considered when comparing results, with important elements including the type of material, geometry and specific characteristics of the associated magnetic pulse.
The core material may be either a magnetically inert substrate ('air core'), or a solid, ferromagnetically active material ('solid core'). Solid cores result in more efficient transfer of electrical energy to a magnetic field and reduce energy loss to heat, and so can be operated with the higher volume of therapy protocols without interruption due to overheating. Varying the geometric shape of the coil itself can cause variations in focality, shape, and depth of penetration. Differences in coil material and its power supply also affect magnetic pulse width and duration.
A number of different types of coils exist, each of which produce different magnetic fields. The round coil is the original used in TMS. Later, the figure-eight (butterfly) coil was developed to provide a more focal pattern of activation in the brain, and the four-leaf coil for focal stimulation of peripheral nerves. The double-cone coil conforms more to the shape of the head. The Hesed (H-core), circular crown and double cone coils allow more widespread activation and a deeper magnetic penetration. They are supposed to impact deeper areas in the motor cortex and cerebellum controlling the legs and pelvic floor, for example, though the increased depth comes at the cost of a less focused magnetic pulse.
Luigi Galvani (1737-1798) undertook research on the effects of electricity on the body in the late-eighteenth century and laid the foundations for the field of electrophysiology. In the 1830s Michael Faraday (1791-1867) discovered that an electrical current had a corresponding magnetic field, and that changing one could induce its counterpart.
Work to directly stimulate the human brain with electricity started in the late 1800s, and by the 1930s the Italian physicians Cerletti and Bini had developed electroconvulsive therapy (ECT). ECT became widely used to treat mental illness, and ultimately overused, as it began to be seen as a panacea. This led to a backlash in the 1970s.
In 1980 Merton and Morton successfully used transcranial electrical stimulation (TES) to stimulate the motor cortex. However, this process was very uncomfortable, and subsequently Anthony T. Barker began to search for an alternative to TES. He began exploring the use of magnetic fields to alter electrical signaling within the brain, and the first stable TMS devices were developed in 1985. They were originally intended[by whom?] as diagnostic and research devices, with evaluation of their therapeutic potential being a later development. The United States' FDA first approved TMS devices in October 2008.
TMS has shown potential with neurologic conditions such as Alzheimer's disease, amyotrophic lateral sclerosis, persistent vegetative states, epilepsy, stroke related disability, tinnitus, multiple sclerosis, schizophrenia, and traumatic brain injury.
With Parkinson's disease, early results suggest that low frequency stimulation may have an effect on medication associated dyskinesia, and that high frequency stimulation improves motor function. The most effective treatment protocols appear to involve high frequency stimulation of the motor cortex, particularly on the dominant side, but with more variable results for treatment of the dorsolateral prefrontal cortex. It is less effective than electroconvulsive therapy for motor symptoms, though both appear to have utility. Cerebellar stimulation has also shown potential for the treatment of levodopa associated dyskinesia.
In psychiatry, it has shown potential with anxiety disorders, including panic disorder and obsessive-compulsive disorder (OCD). The most promising areas to target for OCD appear to be the orbitofrontal cortex and the supplementary motor area. Older protocols that targeted the prefrontal dorsal cortex were less successful. It has also been studied with autism, substance abuse, addiction, and posttraumatic stress disorder (PTSD). For treatment-resistant major depressive disorder, HF-rTMS of the left dorsolateral prefrontal cortex (DLPFC) appears effective and low-frequency (LF) rTMS of the right DLPFC has probable efficacy.
TMS can also be used to map functional connectivity between the cerebellum and other areas of the brain.
Mimicking the physical discomfort of rTMS with placebo to discern its true effect is a challenging issue in research. It is difficult to establish a convincing placebo for TMS during controlled trials in conscious individuals due to the neck pain, headache and twitching in the scalp or upper face associated with the intervention. In addition, placebo manipulations can affect brain sugar metabolism and MEPs, which may confound results. This problem is exacerbated when using subjective measures of improvement. Placebo responses in trials of rTMS in major depression are negatively associated with refractoriness to treatment.
A 2011 review found that most studies did not report blinding. In the minority that did, participants in real and sham rTMS groups were not significantly different in their ability to correctly guess their therapy, though there was a trend for participants in the real group to more often guess correctly.
TMS research in animal studies is limited due to its early FDA approval for treatment-resistant depression, limiting development of animal specific magnetic coils.
Nexstim obtained 510(k) FDA clearance for the assessment of the primary motor cortex for pre-procedural planning in December 2009 and for neurosurgical planning in June 2011.
In 2008, the US Food and Drug Administration authorized the use of rTMS as a treatment for depression that has not improved with other measures. A number of deep TMS have received FDA 510k clearance to market for use in adults with treatment resistant major depressive disorders. The Royal Australian and New Zealand College of Psychiatrists has endorsed rTMS for treatment resistant major depressive disorder (MDD).
The use of single-pulse TMS was approved by the FDA for treatment of migraines in December 2013. It is approved as a Class II medical device under the "de novo pathway".
In the European Economic Area, various versions of Deep TMS H-coils have CE marking for Alzheimer's disease, autism, bipolar disorder, epilepsy  chronic pain major depressive disorder Parkinson's disease, posttraumatic stress disorder (PTSD), schizophrenia (negative symptoms) and to aid smoking cessation. One review found tentative benefit for cognitive enhancement in healthy people.
In August 2018, the US Food and Drug Administration authorized the use of TMS in the treatment of obsessive-compulsive disorder (OCD).
In 2013, several commercial health insurance plans in the United States, including Anthem, Health Net, and Blue Cross Blue Shield of Nebraska and of Rhode Island, covered TMS for the treatment of depression for the first time. In contrast, UnitedHealthcare issued a medical policy for TMS in 2013 that stated there is insufficient evidence that the procedure is beneficial for health outcomes in patients with depression. UnitedHealthcare noted that methodological concerns raised about the scientific evidence studying TMS for depression include small sample size, lack of a validated sham comparison in randomized controlled studies, and variable uses of outcome measures. Other commercial insurance plans whose 2013 medical coverage policies stated that the role of TMS in the treatment of depression and other disorders had not been clearly established or remained investigational included Aetna, Cigna and Regence.
Policies for Medicare coverage vary among local jurisdictions within the Medicare system, and Medicare coverage for TMS has varied among jurisdictions and with time. For example:
The United Kingdom's National Institute for Health and Care Excellence (NICE) issues guidance to the National Health Service (NHS) in England, Wales, Scotland and Northern Ireland. NICE guidance does not cover whether or not the NHS should fund a procedure. Local NHS bodies (primary care trusts and hospital trusts) make decisions about funding after considering the clinical effectiveness of the procedure and whether the procedure represents value for money for the NHS.
NICE evaluated TMS for severe depression (IPG 242) in 2007, and subsequently considered TMS for reassessment in January 2011 but did not change its evaluation. The Institute found that TMS is safe, but there is insufficient evidence for its efficacy.
In January 2014, NICE reported the results of an evaluation of TMS for treating and preventing migraine (IPG 477). NICE found that short-term TMS is safe but there is insufficient evidence to evaluate safety for long-term and frequent uses. It found that evidence on the efficacy of TMS for the treatment of migraine is limited in quantity, that evidence for the prevention of migraine is limited in both quality and quantity.
Subsequently, in 2015, NICE approved the use of TMS for the treatment of depression in the UK and IPG542 replaced IPG242. NICE said "The evidence on repetitive transcranial magnetic stimulation for depression shows no major safety concerns. The evidence on its efficacy in the short-term is adequate, although the clinical response is variable. Repetitive transcranial magnetic stimulation for depression may be used with normal arrangements for clinical governance and audit."
A single TMS session for depressive disorders averages US$350. A full course of treatment could cost between US$6,000 and US$12,000, depending on the number of treatments.
Manufacturers of the devices include Brainsway, Deymed, MagVenture, Mag&More, Magstim, Nexstim, Neuronetics, Neurosoft. Current UK providers include a few NHS Trusts and a private operator, Smart TMS.
Here is the original post:
- TMS (Transcranial Magnetic Stimulation) Coil Market Share Analysis and Research - News by aeresearch - September 8th, 2020
- The TMS Round-Up: Our Favorite Cinematic Vacation Spots - The Mary Sue - September 8th, 2020
- New Comprehensive Report on Transportation and Logistics Software Market to Witness an Outstanding Growth during 2020 2028 with Top Players Like TMW,... - September 8th, 2020
- The Breaking, Known News TMS Therapy for Depression Works - PsychCentral.com - September 4th, 2020
- Column: CNV-X Capstone Project the effects of Alzheimer's and how TMS can help - Los Angeles Times - September 4th, 2020
- Logistics Matters podcast: Philip Evers of the University of Maryland on what's ahead for the US Postal Service | S1 E21 | 2020-08-28 - DC Velocity - September 4th, 2020
- Fast Three: Would You WFH Permanently?, Treating Depression in Pottstown, and Racing Ducks for Cash - The Sanatoga Post - September 4th, 2020
- INTERVIEW: Judy Reyes Talked With Us About the Importance of All Together Now - The Mary Sue - September 4th, 2020
- Technology promotes transparency in transportation, shipping | 2020-08-27 - DC Velocity - September 2nd, 2020
- TAIJI Medical Supplies Inc., a US PPE Manufacturer, Announces Expansion of Manufacturing Capacity Amid Expected Surge of COVID-19 and Influenza Cases... - September 2nd, 2020
- Global High-intensity Focused Ultrasound Therapy Market 2020-2026 | EDAP TMS, SonaCare Medical, Theraclion, ILJIN Holdings, FUS Instruments - NJ MMA... - September 2nd, 2020
- C.H. Robinson heralds integration of 19 TMS and ERP providers into its Navisphere offering - Logistics Management - September 1st, 2020
- Global Impact of Covid-19 on Prostate Cancer Devices Market to Record Significant Revenue Growth During the Forecast Period 20202025 | Galil Medical,... - September 1st, 2020
- Innovative Report on High Intensity Focused Ultrasound Market 2020 Major Players: Chongqing Haifu Medical Technology, Philips Healthcare, Insightec,... - September 1st, 2020
- Which Pokmon To Use Elite Charged TMs On In Pokmon GO - Bleeding Cool News - August 11th, 2020
- Greenbrook TMS Reports Second Quarter Financial Results With Resilient Performance Through the COVID-19 Pandemic - Business Wire - August 11th, 2020
- FLORIDA TMS CLINIC Offers The Best TMS Therapy In The Tampa Bay Area - Press Release - Digital Journal - August 11th, 2020
- RedwoodConnect 2.0 sets sights on simplifying TMS integration - FreightWaves - August 11th, 2020
- Notice of Nexstim Plc's Half-Yearly Report H1 2020 - Yahoo Finance - August 11th, 2020
- Scientists Have Found A Way To Erase Your Worst Fears: What If It Could Amp Up Career Success? - Forbes - August 11th, 2020
- Road construction work underway in Weyburn region - Weyburn Review - August 11th, 2020
- TruckingOffice Integrates TMS with ELD for Seamless Dispatcher Trucker Workflow - PR Web - August 10th, 2020
- Inter-Language Vector Space - Unlocking the Secrets of Language - Slator - August 10th, 2020
- Transportation Management System (TMS) Market Size and Status 2020 Outlook and Forecast to 2026 - eRealty Express - August 10th, 2020
- England v Pakistan: talking points from a thrilling first Test - The Guardian - August 10th, 2020
- High time to fully appreciate the all-round value of Chris Woakes - The Guardian - August 10th, 2020
- Talent Management Software (TMS) Market is Projected to Expand at a Steady CAGR over the Forecast by 2025 - Owned - August 10th, 2020
- If You Had Bought EDAP TMS' (NASDAQ:EDAP) Shares Five Years Ago You Would Be Down 12% - Yahoo Finance - August 10th, 2020
- Transcranial magnetic stimulation - Mayo Clinic - August 8th, 2020
- Tension myositis syndrome - Wikipedia - August 8th, 2020
- I Tried Transcranial Magnetic Stimulation - TMS Therapy as ... - August 8th, 2020
- RedwoodConnect 2.0 Sets Sights On Simplifying TMS Integration - Benzinga - August 8th, 2020
- Transportation Management System (TMS) Market is Projected to Expand at a Steady CAGR over the Forecast by 2025 - Owned - August 8th, 2020
- World TMS (Transcranial Magnetic Stimulation) Coil Market Industry: A Latest Research Report to Share Market Insights and Dynamics - Bulletin Line - August 8th, 2020
- TMS Webinar puts the spotlight on Offshore Oil and Gas - Latest Maritime & Shipping News Online - The Maritime Standard - August 8th, 2020
- Edited Transcript of GTMS.TO earnings conference call or presentation 5-Aug-20 2:00pm GMT - Yahoo Finance - August 8th, 2020
- RedwoodConnect 2.0 Sets Sights On Simplifying TMS Integration - Yahoo Finance - August 7th, 2020
- Alternative Treatment for Depression: Transcranial Magnetic Stimulation (TMS) - LVHN News - August 5th, 2020
- Alpega Partners with project44 to Deliver Advanced Visibility in North America and Europe - Business Wire - August 5th, 2020
- Science Is Inching Closer To Modifying Our Memories Are We Ready For The Mind Eraser? - Forbes - August 5th, 2020
- September 1, deadline to present the transfer markets of the summer of 2021 - Explica - August 5th, 2020
- Rising Demand in TMS(Transcranial Magnetic Stimulation) Coil Market Growth Analysis and Key Business Strategies 2026 - Owned - August 4th, 2020
- EKA and FreightWaves Announce Channel Partner Collaboration to Deliver Most Current Freight Data and Insights to Supply Chain Customers - The Herald... - August 4th, 2020
- Shockwave Therapy Device Market with Competitive Analysis, New Business Developments and Top Companies: Boston Scientific Corporation, CR Bard Inc. -... - August 4th, 2020
- Impact of COVID-19 on Transcranial Magnetic Stimulators (TMS) Market Overview with Detailed Analysis, Competitive Landscape & Forecast To 2024 -... - August 4th, 2020
- Mental Wellness with MindPath: Transcranial Magnetic Stimulation for Depression and OCD - WTVD-TV - August 3rd, 2020
- Nashville NeuroCare Therapy Marks 10-Year Milestone in TMS Therapy for the Treatment of Depression - PRNewswire - August 3rd, 2020
- Pokmon: 5 TMs You Can Buy That Are Absolutely Not Worth The Money (& 5 That Are) - TheGamer - August 3rd, 2020
- Racin' Today Jeff Burton Talks Loudon, TMS, Family And TV - RacinToday.com - August 3rd, 2020
- Reflecting film Market Analysis By Distribution Channel, Region And Forecast From 2020 To 2025|NIPPA, TOYOBO, TMS, Mitsubishi, Esopp Group, etc -... - August 3rd, 2020
- Talent Management Systems (TMS) Market Executive Summary, Introduction, Sizing, Analysis and Forecast To 2025 - Bulletin Line - August 3rd, 2020
- TMS(Transcranial Magnetic Stimulation) Coil Market Forecast to 2025 - Driven by Industry Major Players, Dynamics, Future Opportunities, Revenue,... - August 1st, 2020
- Research Assistant, Grant job with UNITED ARAB EMIRATES UNIVERSITY | 215068 - Times Higher Education (THE) - August 1st, 2020
- Transcranial magnetic stimulation (TMS): Hope for stubborn ... - July 31st, 2020
- Transcranial Magnetic Stimulation (TMS) Therapy ... - July 31st, 2020
- Sebi allows acceptance of client securities as collateral by way of title transfer till August 31 - The Financial Express - July 31st, 2020
- Transportation Management Systems (TMS) Market 2020-2026 scrutinized in the new analysis - WhaTech Technology and Markets News - July 29th, 2020
- Your Healthy Family: Getting help with the stress of uncertainty during a pandemic - KOAA.com Colorado Springs and Pueblo News - July 29th, 2020
- Treasury Management System (TMS) Market by Technology Innovations and Growth 2020 to 2027 - Bulletin Line - July 29th, 2020
- Sebi allows acceptance of client securities as collateral by way of title transfer till Aug 31 - Devdiscourse - July 29th, 2020
- Global TMS(Transcranial Magnetic Stimulation) Coil Market 2020 Industry Analysis, Size, Share, Growth, Trend and Forecast to 2025 - Red & Black... - July 25th, 2020
- Neurostimulation may herald a new treatment for depression - The Conversation CA - July 25th, 2020
- Racin' Today Dillon Answers 'Haters' With Victory In Texas - RacinToday.com - July 25th, 2020
- Coronavirus: Fifa gives Safa the power to extend the 2019-20 PSL season - Goal.com - July 25th, 2020
- For those in Salem with depression, new clinic provides another resource for treatment - Salem Reporter - July 25th, 2020
- Penn Medicine: Launching the Region's First Center for Translational Neuromodulation - UPENN Almanac - July 25th, 2020
- Coronavirus: Fifa gives Safa the power to extend the 2019-20 PSL season - Yahoo Sports - July 24th, 2020
- Your Healthy Family: The reason so many people are stressed out right now - KOAA.com Colorado Springs and Pueblo News - July 24th, 2020
- Global TMS(TRANSCRANIAL MAGNETIC STIMULATION) COIL Market 2020 to 2025: Industry Scope of the Research - Jewish Life News - July 21st, 2020
- ORANGEBURG PROPERTY TRANSFERS - The Times and Democrat - July 21st, 2020
- 'Dr. Stone' season 2 spoilers: TMS drops new teaser and here's what it revealed about Senku and the 'Stone Wars' arc - EconoTimes - July 21st, 2020
- Mauritius club fined for not doing the TMS paperwork - Inside World Football - July 21st, 2020
- Seamount announces addition of Chassis Assets to their Drayage Fleet - DC Velocity - July 21st, 2020
- GEMoaB and Intellia Therapeutics Enter into Research Collaboration and Licensing Agreement on Next-Generation Cellular Immunotherapy Based on... - July 21st, 2020
- Shockwave Therapy Device Market Overview, Industry Top Manufactures, Market Size, Industry Growth Analysis And Forecasts 2026 |CR Bard Inc., Dornier... - July 20th, 2020
- Fans to return to TMS on Sunday for NASCAR race - Jacksonville Daily Progress - July 18th, 2020
- Press Release: Active Recovery TMS Opens Salem Clinic New Salem-Area Clinic Will Help With Treatment For Depression - The Lund Report - July 15th, 2020
- How to Solve the Digital Transportation Puzzle - FreightWaves - July 15th, 2020
- Global Transportation Management System (TMS) Market 2020: Size, Share, Revenue, Growth, Supply, Top Companies and Forecast Research 2025 - Sports... - July 15th, 2020
- ARL Logistics Taps Trucker Tools for Smart Capacity Predictive Freight-Matching, Automated One-Click Load Booking with Book It Now - PR Web - July 15th, 2020