Transcranial magnetic stimulation
|Transcranial magnetic stimulation|
Transcranial magnetic stimulation (schematic diagram)
Transcranial magnetic stimulation (TMS) is a noninvasive method to cause depolarization or hyperpolarization in the neurons of the brain. TMS uses electromagnetic induction to induce weak electric currents using a rapidly changing magnetic field; this can cause activity in specific or general parts of the brain with minimal discomfort, allowing for study of the brain's functioning and interconnections. A variant of TMS, repetitive transcranial magnetic stimulation (rTMS) has been tested as a treatment tool for various neurological and psychiatric disorders including migraine, stroke, Parkinson's disease, dystonia, tinnitus and depression.
- 1 Background
- 2 Theory
- 3 Effects on the brain
- 4 Accuracy
- 5 Risks
- 6 Clinical uses
- 7 FDA actions
- 8 Health insurance considerations
- 9 American Medical Association category codes
- 10 Technical information
- 11 See also
- 12 References
- 13 Further reading
- 14 External links
Early attempts at stimulation of the brain using a magnetic field included those, in 1910, of Silvanus P. Thompson in London. The principle of inductive brain stimulation with eddy currents has been noted since the 20th century. The first successful TMS study was performed in 1985 by Anthony Barker and his colleagues at the Royal Hallamshire Hospital in Sheffield, England. Its earliest application demonstrated conduction of nerve impulses from the motor cortex to the spinal cord, stimulating muscle contractions in the hand. As compared to the previous method of transcranial stimulation proposed by Merton and Morton in 1980 in which direct electrical current was applied to the scalp, the use of electromagnets greatly reduced the discomfort of the procedure, and allowed mapping of the cerebral cortex and its connections.
From the Biot-Savart 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 of 1-10 mT. By directing the magnetic field pulse at a targeted area of the brain, one can either depolarize or hyperpolarize neurons in the brain. The magnetic flux density pulse generated by the current pulse through the coil causes an electric field due to the Maxwell-Faraday equation,
This electric field causes a change in the transmembrane current of the neuron, which leads to the depolarization or hyperpolarization of the neuron and the firing of an action potential.
Effects on the brain
The exact details of how TMS functions are still being explored. The effects of TMS can be divided into two types depending on the mode of stimulation:
- Single or paired pulse TMS causes neurons in the neocortex under the site of stimulation to depolarize and discharge an action potential. If used in the primary motor cortex, it produces muscle activity referred to as a motor evoked potential (MEP) which can be recorded on electromyography. If used on the occipital cortex, 'phosphenes' (flashes of light) might be perceived by the subject. In most other areas of the cortex, the participant does not consciously experience any effect, but his or her behaviour may be slightly altered (e.g., slower reaction time on a cognitive task), or changes in brain activity may be detected using sensing equipment.
- Repetitive TMS produces longer-lasting effects which persist past the initial period of stimulation. rTMS can increase or decrease the excitability of the corticospinal tract depending on the intensity of stimulation, coil orientation, and frequency. The mechanism of these effects is not clear, though it is widely believed to reflect changes in synaptic efficacy akin to long-term potentiation (LTP) and long-term depression (LTD).
In 1996, a study was done by Wassermann et al. using TMS to stimulate areas in the motor cortex of the brain to move a finger. The stimulated areas were imaged with an MRI for the reference image. The subjects then were asked to move the same finger in the same way that it was moved by TMS, and PET images were obtained to map the corresponding activity in the brain. The TMS-induced MRI images matched very closely with the PET images, within 5–22 mm of accuracy. TMS has also been seen to correlate closely to MEG and also fMRI.
TMS is generally regarded as safe, although seizures have been reported in some cases. There have been 16 reports of TMS-related seizures (as of 2009), with seven reported before the publication of safety guidelines in 1998, and nine reported afterwards. The seizures have been associated with both single-pulse and rTMS. Reports have stated that in at least some cases, predisposing factors (medication, brain lesions or genetic susceptibility) may have contributed to the seizure. A review of nine seizures associated with rTMS that had been reported after 1998 stated that four seizures were within the safety parameters, four were outside of those parameters, and one had occurred in a healthy volunteer with no predisposing factors. A 2009 international consensus statement on TMS that contained this review concluded that based on the number of studies, subjects, and patients involved with TMS research, the risk of seizure with rTMS is considered very low.
Besides seizures, other risks include syncope (fainting), minor pains such as headache or local discomfort, minor cognitive changes, and psychiatric symptoms (particularly a low risk of mania in depressed patients). Though other side effects are thought to be possibly associated with TMS (alterations to the endocrine system, altered neurotransmitter, and immune system activity) they are considered investigational and lacking substantive proof.
Other adverse effects of TMS are:
- Discomfort or pain from the stimulation of the scalp and associated nerves and muscles on the overlying skin; this is more common with rTMS than single pulse TMS.
- Rapid deformation of the TMS coil produces a loud clicking sound that increases with the stimulation intensity and can affect hearing with sufficient exposure, which is particularly relevant for rTMS (hearing protection may be used to prevent this).
- rTMS in the presence of EEG-incompatible electrodes can result in electrode heating and, in severe cases, skin burns. Non-metallic electrodes are used if concurrent EEG data is required.
The uses of TMS and rTMS can be divided into diagnostic and therapeutic uses.
TMS can be used clinically to measure activity and function of specific brain circuits in humans. The most robust and widely accepted use is in measuring the connection between the primary motor cortex and a muscle to evaluate damage from stroke, multiple sclerosis, amyotrophic lateral sclerosis, movement disorders, motor neuron disease and injuries and other disorders affecting the facial and other cranial nerves and the spinal cord. TMS has been suggested as a means of assessing short-interval intracortical inhibition (SICI) which measures the internal pathways of the motor cortex but this use has not yet been validated.
Studies of the use of TMS and rTMS to treat many neurological and psychiatric conditions have generally shown only modest effects with little confirmation of results. However, publications reporting the results of reviews and statistical meta-analyses of earlier investigations have stated that rTMS appeared to be effective in the treatment of certain types of major depression under certain specific conditions. rTMS devices are marketed for the treatment of such disorders in Canada, Australia, New Zealand, the European Union, Israel and the United States.
A meta-analysis of 34 studies comparing rTMS to sham treatment for the acute treatment of depression showed an effect size of 0.55 (p<.001). This is comparable to commonly reported effect sizes of pharmacotherapeutic strategies for treatment of depression in the range of 0.17-0.46. However, that same meta-analysis found that rTMS was significantly worse than electroconvulsive therapy (ECT) (effect size = -0.47), although side effects were significantly better with rTMS. An analysis of one of the studies included in the meta-analysis showed that one extra remission from depression occurs for every 3 patients given electroconvulsive therapy rather than rTMS (number needed to treat 2.36). There is evidence that rTMS can temporarily reduce chronic pain and change pain-related brain and nerve activity, and TMS has been used to predict the success of surgically implanted electrical brain stimulation for the treatment of pain.
Other areas of research include the rehabilitation of aphasia and motor disability after stroke, tinnitus, Parkinson's disease, tic disorders, possiblly PTSD and the negative symptoms of schizophrenia. TMS has failed to show effectiveness for the treatment of brain death, coma, and other persistent vegetative states.
It is difficult to establish a convincing form of "sham" TMS to test for placebo effects during controlled trials in conscious individuals, due to the neck pain, headache and twitching in the scalp or upper face associated with the intervention. "Sham" TMS manipulations can affect cerebral glucose 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, vary among studies and can influence results. Depending on the research question asked and the experimental design, matching the discomfort of rTMS to distinguish true effects from placebo can be an important and challenging issue.
One multicenter trial of rTMS in depression used an active "sham" placebo treatment that appeared to mimic the sound and scalp stimulation associated with active TMS treatment. The investigators reported that the patients and clinical raters were unable to guess the treatment better than chance, suggesting that the sham placebo adequately blinded these people to treatment. The investigators concluded: "Although the treatment effect was statistically significant on a clinically meaningful variable (remission), the overall number of remitters and responders was less than one would like with a treatment that requires daily intervention for 3 weeks or more, even with a benign adverse effect profile". However, a review of the trial's report has questioned the adequacy of the placebo, noting that treaters were able to guess whether patients were receiving treatment with active or sham TMS, better than chance. In this regard, the trial's report stated that the confidence ratings for the treaters' guesses were low.
In January 2007, an advisory panel of the United States Food and Drug Administration (FDA) did not recommend clearance for marketing of an rTMS device, stating that the device appeared to be reasonably safe but had failed to demonstrate efficacy in a study of people with major depression who had not benefitted from prior adequate treatment with oral antidepressants during their current major depressive episode. The panel agreed that "unblinding was greater in the active group, and considering the magnitude of the effect size, it may have influenced the study results." However, the FDA determined in December 2008 that the rTMS device was sufficiently similar to existing devices that did not require a premarket approval application and allowed the device to be marketed in accordance with Section 510(k) of the Federal Food, Drug, and Cosmetic Act for "the treatment of Major Depressive Disorder in adult patients who have failed to achieve satisfactory improvement from one prior antidepressant medication at or above the minimal effective dose and duration in the current episode". The user manual for the device warns that effectiveness has not been established in patients with major depressive disorder who have failed to achieve satisfactory improvement from zero and from two or more antidepressant medications in the current episode and that the device has not been studied in patients who have had no prior antidepressant medication.
In July 2011, the FDA published a final rule in the Federal Register that classified the rTMS system into Class II (special controls) "in order to provide a reasonable assurance of safety and effectiveness of these devices". The rule identified the rTMS system as "an external device that delivers transcranial pulsed magnetic fields of sufficient magnitude to induce neural action potentials in the prefrontal cortex to treat the symptoms of major depressive disorder without inducing seizure in patients who have failed at least one antidepressant medication and are currently not on any antidepressant therapy". An FDA guidance document issued in conjunction with the final rule describes the special controls that support the classification of the rTMS system into Class II.
Response to FDA decision
Soon after the FDA cleared the device, several members of Public Citizen stated in a letter to the editor of the medical journal Neuropsychopharmacology that the FDA seemed to have based its decision on a post-hoc analysis that did not establish the effectiveness of rTMS for the treatment of depression. The writers of the letter expressed their concern that patients would be diverted from therapies such as antidepressant medications that have an established history of effectiveness.
Health insurance considerations
Commercial health insurance
In July 2011, the Technology Evaluation Center (TEC) of the Blue Cross Blue Shield Association, in cooperation with the Kaiser Foundation Health Plan and the Southern California Permanente Medical Group, determined that TMS for the treatment of depression did not meet the TEC's criteria, which assess whether a technology improves health outcomes such as length of life, quality of life and functional ability. The TEC's report stated that "the meta-analyses and recent clinical trials of TMS generally show statistically significant effects on depression outcomes at the end of the TMS treatment period. However, there is a lack of rigorous evaluation beyond the treatment period", which was, with a few exceptions, one to four weeks. The Blue Cross Blue Shield Association's medical advisory panel concluded that "the available evidence does not permit conclusions regarding the effect of TMS on health outcomes or compared with alternatives.”
In 2012, 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. In contrast, UnitedHealthcare issued a medical policy for TMS in 2012 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 2012 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.
In early 2012, the efforts of TMS treatment advocates, including a Rhode Island physician who used TMS in her practice to treat patients with depression, resulted in the approval for the New England region of the first Medicare coverage policy for TMS in the United States. However, in August 2012, the Medicare administrative contractor for the Centers for Medicare and Medicaid Services jurisdiction covering Arkansas, Louisiana, Mississippi, Colorado, Texas, Oklahoma and New Mexico determined that, based on limitations in the published literature,
... the evidence is insufficient to determine rTMS improves health outcomes in the Medicare or general population. ... The contractor considers repetitive transcranial magnetic stimulation (rTMS) not medically necessary when used for its FDA-approved indication and for all off-label uses.
National Health Service
The United Kingdom's National Institute for Health and Clinical Excellence 2007 guidance to the National Health Service in England, Wales, Scotland and Northern Ireland on transcranial magnetic stimulation for severe depression (IPG242), considered for reassessment in January 2011, states:
Current evidence suggests that there are no major safety concerns associated with transcranial magnetic stimulation (TMS) for severe depression. There is uncertainty about the procedure's clinical efficacy, which may depend on higher intensity, greater frequency, bilateral application and/or longer treatment durations than have appeared in the evidence to date. TMS should therefore be performed only in research studies designed to investigate these factors.
American Medical Association category codes
In 2011, the American Medical Association established three Category I CPT® Codes to be used for the reporting and billing of therapeutic repetitive transcranial magnetic stimulation treatment services. The three codes effective January 1, 2012 are:
- 90867 – Therapeutic repetitive transcranial magnetic stimulation (TMS) treatment; initial, including cortical mapping, motor threshold determination, delivery and management
- 90868 – Therapeutic repetitive transcranial magnetic stimulation (TMS) treatment; subsequent delivery and management, per session
- 90869 – Therapeutic repetitive transcranial magnetic stimulation (TMS) treatment; subsequent motor threshold re-determination with delivery and management
TMS uses electromagnetic induction to generate an electric current across the scalp and skull without physical contact. 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 passes unimpeded through the skin and skull, inducing an oppositely directed current in the brain that activates nearby nerve cells in much the same way as currents applied directly to the cortical surface.
The path of this current is difficult to model because the brain is irregularly shaped and electricity and magnetism are not conducted uniformly throughout its tissues. 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 the deep transcranial magnetic stimulation variant of TMS. Deep TMS can reach up to 6 cm into the brain to stimulate deeper layers of the motor cortex, such as that which controls leg motion.
The design of transcranial magnetic stimulation coils used in either treatment or diagnostic/experimental studies may differ in a variety of ways. These differences should be considered in the interpretation of any study result, and the type of coil used should be specified in the study methods for any published reports.
The most important considerations include:
- the type of material used to construct the core of the coil
- the geometry of the coil configuration
- the biophysical characteristics of the pulse produced by the coil.
With regard to coil composition, the core material may be either a magnetically inert substrate (i.e., the so-called ‘air-core’ coil design), or possess a solid, ferromagnetically active material (i.e., the so-called ‘solid-core’ design). Solid core coil design result in a more efficient transfer of electrical energy into a magnetic field, with a substantially reduced amount of energy dissipated as heat, and so can be operated under more aggressive duty cycles often mandated in therapeutic protocols, without treatment interruption due to heat accumulation, or the use of an accessory method of cooling the coil during operation. Varying the geometric shape of the coil itself may also result in variations in the focality, shape, and depth of cortical penetration of the magnetic field. Differences in the coil substance as well as the electronic operation of the power supply to the coil may also result in variations in the biophysical characteristics of the resulting magnetic pulse (e.g., width or duration of the magnetic field pulse). All of these features should be considered when comparing results obtained from different studies, with respect to both safety and efficacy.
A number of different types of coils exist, each of which produce different magnetic field patterns. Some examples:
- round coil: the original type of TMS coil
- figure-eight coil (i.e., butterfly coil): results in a more focal pattern of activation
- double-cone coil: conforms to shape of head, useful for deeper stimulation
- four-leaf coil: for focal stimulation of peripheral nerves
- H-coil: for deep transcranial magnetic stimulation
Design variations in the shape of the TMS coils allow much deeper penetration of the brain than the standard depth of 1.5-2.5 cm. Circular crown coils, Hesed (or H-core) coils, double cone coils, and other experimental variations can induce excitation or inhibition of neurons deeper in the brain including activation of motor neurons for the cerebellum, legs and pelvic floor. Though able to penetrate deeper in the brain, they are less able to produced a focused, localized response and are relatively non-focal.
- Cranial electrotherapy stimulation
- Transcranial direct current stimulation
- Electroconvulsive therapy
- Cortical stimulation mapping
- Anthony T. Barker and Ian Freeston (2007). "Transcranial magnetic stimulation". scholarpedia.org. Retrieved 28 June 2013.
- Barker, AT; Jalinous, R; Freeston, IL (1985). "Non-Invasive Magnetic Stimulation of Human Motor Cortex". The Lancet 325 (8437): 1106–1107. doi:10.1016/S0140-6736(85)92413-4. PMID 2860322.
- Merton, P. A.; Morton, H. B. (1980). "Stimulation of the cerebral cortex in the intact human subject". Nature 285 (5762): 227. doi:10.1038/285227a0. PMID 7374773.
- V. Walsh and A. Pascual-Leone, "Transcranial Magnetic Stimulation: A Neurochronometrics of Mind." Cambridge, MA: MIT Press, 2003.
- Pascual-Leone A; Davey N; Rothwell J; Wassermann EM; Puri BK (2002). Handbook of Transcranial Magnetic Stimulation. London: Arnold. ISBN 0-340-72009-3.
- Fitzgerald, P; Fountain, S; Daskalakis, Z (2006). "A comprehensive review of the effects of rTMS on motor cortical excitability and inhibition". Clinical Neurophysiology 117 (12): 2584–2596. doi:10.1016/j.clinph.2006.06.712. PMID 16890483.
- Wassermann, E. M.; Wang, B.; Zeffiro, T. A.; Sadato, N.; Pascual-Leone, A.; Toro, C.; Hallett, M. (1996). "Locating the Motor Cortex on the MRI with Transcranial Magnetic Stimulation and PET". NeuroImage 3 (1): 1–9. doi:10.1006/nimg.1996.0001. PMID 9345470.
- T. Morioka, T. Yamamoto, A. Mizushima, S. Tombimatsu, H. Shigeto, K. Hasuo, S. Nishio, K. Fujii and M. Fukui. Comparison of magnetoencephalography, functional MRI, and motor evoked potentials in the localization of the sensory-motor cortex. Neurol. Res., vol. 17, no. 5, pp. 361-367. 1995
- Terao, Y.; Ugawa, Y.; Sakai, K.; Miyauchi, S.; Fukuda, H.; Sasaki, Y.; Takino, R.; Hanajima, R.; Furubayashi, T.; püTz, B.; Kanazawa, I. (1998). "Localizing the site of magnetic brain stimulation by functional MRI". Experimental Brain Research 121 (2): 145. doi:10.1007/s002210050446.
- Rossi, S; Hallett, M; Rossini, PM; Pascual-Leone, A; Safety of TMS Consensus Group (2009). "Safety, ethical considerations, and application guidelines for the use of transcranial magnetic stimulation in clinical practice and research". Clinical Neurophysiology 120 (12): 2008–2039. doi:10.1016/j.clinph.2009.08.016. PMID 19833552.
- Wassermann, EM (1998). "Risk and safety of repetitive transcranial magnetic stimulation: Report and suggested guidelines from the International Workshop on the Safety of Repetitive Transcranial Magnetic Stimulation, June 5–7, 1996". Electroencephalography and Clinical Neurophysiology/Evoked Potentials Section 108: 1–9. doi:10.1016/S0168-5597(97)00096-8. PMID 9474057.
- "Transcranial Magnetic Stimulation (TMS)". National Alliance on Mental Illness. Retrieved 2008-12-15.
- Roth, BJ; Pascual-Leone, A; Cohen, LG; Hallett, M (1992). "The heating of metal electrodes during rapid-rate magnetic stimulation: A possible safety hazard". Electroencephalography and Clinical Neurophysiology/Evoked Potentials Section 85 (2): 116. doi:10.1016/0168-5597(92)90077-O. PMID 1373364.
- Groppa, S.; Oliviero, A.; Eisen, A.; Quartarone, A.; Cohen, L. G.; Mall, V.; Kaelin-Lang, A.; Mima, T.; Rossi, S.; Thickbroom, G. W.; Rossini, P. M.; Ziemann, U.; Valls-Solé, J.; Siebner, H. R. (2012). "A practical guide to diagnostic transcranial magnetic stimulation: Report of an IFCN committee". Clinical Neurophysiology 123 (5): 858–882. doi:10.1016/j.clinph.2012.01.010. PMID 22349304.
- Rossini, P; Rossi, S (2007). "Transcranial magnetic stimulation: diagnostic, therapeutic, and research potential". Neurology 68 (7): 484–488. doi:10.1212/01.wnl.0000250268.13789.b2. PMID 17296913.
- Dimyan, MA; Cohen, LG (2009). "Contribution of Transcranial Magnetic Stimulation to the Understanding of Functional Recovery Mechanisms After Stroke". Neurorehabilitation and Neural Repair 24 (2): 125–135. doi:10.1177/1545968309345270. PMC 2945387. PMID 19767591.
- Nowak, D; Bösl, K; Podubeckà, J; Carey, J (2010). "Noninvasive brain stimulation and motor recovery after stroke". Restorative Neurology and Neuroscience 28 (4): 531–544. doi:10.3233/RNN-2010-0552. PMID 20714076.
- Kujirai, T.; Caramia, M. D.; Rothwell, J. C.; Day, B. L.; Thompson, P. D.; Ferbert, A.; Wroe, S.; Asselman, P.; Marsden, C. D. (1993). "Corticocortical inhibition in human motor cortex". The Journal of physiology 471: 501–519. PMC 1143973. PMID 8120818.
- Slotema, C. W.; Blom, J. D.; Hoek, H. W.; Sommer, I. E. C. (2010). "Should We Expand the Toolbox of Psychiatric Treatment Methods to Include Repetitive Transcranial Magnetic Stimulation (rTMS)?". The Journal of Clinical Psychiatry 71 (7): 873–884. doi:10.4088/JCP.08m04872gre. PMID 20361902.
- Bersani, F. S.; Minichino, F. S.; Capra, E.; Bonanno, R.; Pannese, C.; Salviati, M.; Chiaie, D.; Biondi, M. (2012). "ECT, rTMS, and deepTMS in pharmacoresistant drug-free patients with unipolar depression: A comparative review". Neuropsychiatric Disease and Treatment 8: 55–64. doi:10.2147/NDT.S27025. PMC 3280107. PMID 22347797.
- Marangell, LB; Martinez, M; Jurdi, RA; Zboyan, H (2007). "Neurostimulation therapies in depression: a review of new modalities". Acta Psychiatrica Scandinavica 116 (3): 174. doi:10.1111/j.1600-0447.2007.01033.x. PMID 17655558.
- (1) Medical Advisory Secretariat (2004). "Repetitive transcranial magnetic stimulation for the treatment of major depressive disorder: an evidence-based analysis" (pdf). Ontario Health Technology Assessment Series 4 (7). Archived from the original on 2012-11-28. Retrieved 2012-11-28.
(2) Marangell, LB; Martinez, M; Jurdi, RA; Zboyan, H (2007). "Neurostimulation therapies in depression: a review of new modalities". Acta Psychiatrica Scandinavica 116 (3): 174. doi:10.1111/j.1600-0447.2007.01033.x. PMID 17655558.
(3) Schutter, D (2008). "Antidepressant efficacy of high-frequency transcranial magnetic stimulation over the left dorsolateral prefrontal cortex in double-blind sham-controlled designs: a meta-analysis". Psychological Medicine 39 (1): 65–75. doi:10.1017/S0033291708003462. PMID 18447962.
(4) Lam, RW; Chan, P; Wilkins-Ho, M; Yatham, LN (2008). "Repetitive transcranial magnetic stimulation for treatment-resistant depression: A systematic review and metaanalysis". Canadian journal of psychiatry. Revue canadienne de psychiatrie 53 (9): 621–631. PMID 18801225.
(5) Dell'Osso, B; Camuri, G; Castellano, F; Vecchi, V; Benedetti, M; Bortolussi, S; Altamura, AC (2011). "Meta-Review of Metanalytic Studies with Repetitive Transcranial Magnetic Stimulation (rTMS) for the Treatment of Major Depression". Clinical Practice & Epidemiology in Mental Health 7: 167–177. doi:10.2174/1745017901107010167. PMC 3227860. PMID 22135698.
(6) George, MS; Post, RM (2011). "Daily Left Prefrontal Repetitive Transcranial Magnetic Stimulation for Acute Treatment of Medication-Resistant Depression". American Journal of Psychiatry 168 (4): 356–364. doi:10.1176/appi.ajp.2010.10060864. PMID 21474597.
(7) Gaynes BN, Lux L, Lloyd S, Hansen RA, Gartlehner G, Thieda P, Brode S, Swinson Evans T, Jonas D, Crotty K, Viswanathan M, Lohr KN, Research Triangle Park, North Carolina (September 2011). "Nonpharmacologic Interventions for Treatment-Resistant Depression in Adults. Comparative Effectiveness Review Number 33. (Prepared by RTI International-University of North Carolina (RTI-UNC) Evidence-based Practice Center)". AHRQ Publication No. 11-EHC056-EF. Rockville, Maryland: Agency for Healthcare Research and Quality. p. 36. Archived from the original on 2012-10-11. Retrieved 2011-10-11.
(8) Dirmaier, J.; Steinmann, M.; Krattenmacher, T.; Watzke, B.; Barghaan, D.; Koch, U.; Schulz, H. (2012). "Non-pharmacological treatment of depressive disorders: A review of evidence-based treatment options". Reviews on recent clinical trials 7 (2): 141–149. doi:10.2174/157488712800100233. PMID 22353197.
(9) Bersani, FS; Minichino, A; Enticott, PG; Mazzarini, L; Khan, N; Antonacci, G; Raccah, RN; Salviati, M; Delle Chiaie, R; Bersani, G; Fitzgerald, PB; Biondi, M (2013). "Deep transcranial magnetic stimulation as a treatment for psychiatric disorders: A comprehensive review". European Psychiatry 28 (1): 30–39. doi:10.1016/j.eurpsy.2012.02.006. PMID 22559998.
- Melkerson, MN (2008-12-16). "Special Premarket 510(k) Notification for NeuroStar TMS Therapy System for Major Depressive Disorder" (pdf). Food and Drug Administration. Retrieved 2010-07-16.
- Eranti, S.; Mogg, A.; Pluck, G.; Landau, S.; Purvis, R.; Brown, R. G.; Howard, R.; Knapp, M.; Philpot, M.; Rabe-Hesketh, S.; Romeo, R.; Rothwell, J.; Edwards, D.; McLoughlin, D. M. (2007). "A Randomized, Controlled Trial with 6-Month Follow-Up of Repetitive Transcranial Magnetic Stimulation and Electroconvulsive Therapy for Severe Depression". American Journal of Psychiatry 164 (1): 73–81. doi:10.1176/appi.ajp.164.1.73. PMID 17202547.
- Rosen, AC; Ramkumar, M; Nguyen, T; Hoeft, F (2009). "Noninvasive Transcranial Brain Stimulation and Pain". Current Pain and Headache Reports 13 (1): 12–17. doi:10.1007/s11916-009-0004-2. PMC 2697608. PMID 19126365.
- (1) Martin, PI; Naeser, MA; Ho, M; Treglia, E; Kaplan, E; Baker, EH; Pascual-Leone, A (2009). "Research with Transcranial Magnetic Stimulation in the Treatment of Aphasia". Current Neurology and Neuroscience Reports 9 (6): 451–458. doi:10.1007/s11910-009-0067-9. PMC 2887285. PMID 19818232.
(2) Corti, M; Patten, C; Triggs, W (2012). "Repetitive Transcranial Magnetic Stimulation of Motor Cortex after Stroke". American Journal of Physical Medicine & Rehabilitation 91 (3): 254–270. doi:10.1097/PHM.0b013e318228bf0c. PMID 22042336.
- Kleinjung, T; Vielsmeier, V; Landgrebe, M; Hajak, G; Langguth, B (2008). "Transcranial magnetic stimulation: a new diagnostic and therapeutic tool for tinnitus patients". The international tinnitus journal 14 (2): 112–8. PMID 19205161.
- Lefaucheur, JP (2009). "Treatment of Parkinson’s disease by cortical stimulation". Expert Review of Neurotherapeutics 9 (12): 1755–1771. doi:10.1586/ern.09.132. PMID 19951135.
- Arias-Carrión, O (2008). "Basic mechanisms of rTMS: Implications in Parkinson's disease". International Archives of Medicine 1 (1): 2. doi:10.1186/1755-7682-1-2. PMC 2375865. PMID 18471317.
- Steeves, T.; McKinlay, B. D.; Gorman, D.; Billinghurst, L.; Day, L.; Carroll, A.; Dion, Y.; Doja, A.; Luscombe, S.; Sandor, P.; Pringsheim, T. (2012). "Canadian guidelines for the evidence-based treatment of tic disorders: Behavioural therapy, deep brain stimulation, and transcranial magnetic stimulation". Canadian journal of psychiatry. Revue canadienne de psychiatrie 57 (3): 144–151. PMID 22398000.
- Dlabač-De Lange, JJ; Knegtering, R; Aleman, A (2010). "Repetitive Transcranial Magnetic Stimulation for Negative Symptoms of Schizophrenia". The Journal of Clinical Psychiatry 71 (4): 411. doi:10.4088/JCP.08r04808yel. PMID 20361909.
- Lapitska, N; Gosseries, O; Delvaux, V; Overgaard, M; Nielsen, F; Maertens De Noordhout, A; Moonen, G; Laureys, S (2009). "Transcranial magnetic stimulation in disorders of consciousness". Reviews in the neurosciences 20 (3-4): 235–50. PMID 20157993.
- Brunoni, A. R.; Lopes, M.; Kaptchuk, T. J.; Fregni, F. (2009). "Placebo Response of Non-Pharmacological and Pharmacological Trials in Major Depression: A Systematic Review and Meta-Analysis". In Hashimoto, Kenji. PLoS ONE 4 (3): e4824. doi:10.1371/journal.pone.0004824. PMC 2653635. PMID 19293925.
- George, M. S.; Lisanby, S. H.; Avery, D.; McDonald, W. M.; Durkalski, V.; Pavlicova, M.; Anderson, B.; Nahas, Z.; Bulow, P.; Zarkowski, P.; Holtzheimer Pe, 3.; Schwartz, T.; Sackeim, H. A. (2010). "Daily Left Prefrontal Transcranial Magnetic Stimulation Therapy for Major Depressive Disorder: A Sham-Controlled Randomized Trial". Archives of General Psychiatry 67 (5): 507–516. doi:10.1001/archgenpsychiatry.2010.46. PMID 20439832.
- Mattes, Jeffrey A (2010-06-29). "TMS: Does it Really Work". Archives of General Psychiatry (American Medical Association). Archived from the original on 2011-01-16. Retrieved 2012-08-01.
- Scudiero, JL (2007-01-26). "Brief Summary From the Neurological Devices Panel Meeting - January 26, 2007". FDA. Retrieved 2010-07-14. "The Panel’s consensus was that the efficacy was not established; some stated that the device’s effectiveness was “small,” “borderline,” “marginal” and “of questionable clinical significance.”"
- NeuroStar TMS Therapy System User Manual 1. Neuronetics, Inc. pp. 1–5. Retrieved 2010-09-13.
- Stade, NK, Deputy Director for Policy, Center for Devices and Radiological Health, Food and Drug Administration, United States Department of Health and Human Services (2011-07-26). "Medical Devices; Neurological Devices; Classification of Repetitive Transcranial Magnetic Stimulation System: Final rule". Federal Register (United States Government Printing Office) 76 (143): 44489–44491. Retrieved 2011-08-11.
- U.S. Department of Health and Human Services: Food and Drug Administration: Center for Devices and Radiological Health: Office of Device Evaluation: Division of Ophthalmic, Neurological and Ear, Nose and Throat Devices: Neurodiagnostic and Neurotherapeutic Devices Branch (2011-07-26). "Guidance for Industry and FDA Staff - Class II Special Controls Guidance Document: Repetitive Transcranial Magnetic Stimulation (rTMS) Systems". U.S. Food and Drug Administration. Retrieved 2011-08-10.
- Hines, JZ; Lurie, P; Wolfe SM, Sidney M (2009). "Reply to Lisanby et al.: Post hoc analysis does not establish effectiveness of rTMS for depression" (pdf). Neuropsychopharmacology 34 (8): 2053–2054. doi:10.1038/npp.2009.22. PMID 19528946.
- "Technology Evaluation Center Criteria". Technology Evaluation Center (TEC). Blue Cross Blue Shield Association. Retrieved 2012-10-12.
- "Transcranial Magnetic Stimulation for Depression". TEC Assessment Program (Blue Cross Blue Shield Association) 26 (3). July 2011. Archived from the original on 2012-10-12. Retrieved 2012-10-12.
- (1) Anthem (2012-08-09). "Medical Policy: Transcranial Magnetic Stimulation for Depression and Other Neuropsychiatric Disorders". Policy No. BEH.00002. Anthem. Archived from the original on 2012-10-11. Retrieved 2012-09-05.
(2) Health Net (March 2012). "National Medical Policy: Transcranial Magnetic Stimulation". Policy Number NMP 508. Health Net. Archived from the original on 2012-10-11. Retrieved 2012-09-05.
(3) Blue Cross Blue Shield of Nebraska (2011-05-2011). "Medical Policy Manual". Section IV.67. Blue Cross Blue Shield of Nebraska. Archived from the original on 2012-10-11.
(4) Blue Cross Blue Shield of Rhode Island (2012-05-15). "Medical Coverage Policy: Transcranial Magnetic Stimulation for Treatment of Depression and Other Psychiatric/Neurologic Disorders". Blue Cross Blue Shield of Rhode Island. Archived from the original on 2012-10-11. Retrieved 2012-09-05.
- UnitedHealthcare (2012-01-01). "Transcranial Magnetic Stimulation". Policy Number 2012T0536D. UnitedHealthCare. p. 2. Archived from the original on 2012-10-11. Retrieved 2012-10-11.
- (1) Aetna (2012). "Clinical Policy Bulletin: Transcranial Magnetic Stimulation and Cranial Electrical Stimulation". Number 0469. Aetna. Archived from the original on 2012-10-17. Retrieved 2012-10-17.
(2) Cigna (2012-01-15). "Cigna Medical Coverage Policy: Transcranial Magnetic Stimulation". Coverage Policy Number 0383. Cigna. Archived from the original on 2012-10-17. Retrieved 2012-10-17.
(3) Regence (2012-04-02). "Medical Policy: Transcranial Magnetic Stimulation as a Treatment of Depression and Other Disorders". Policy No. 17. Regence. Archived from the original on 2012-10-17. Retrieved 2012-10-17.
- (1) Centers for Medicare and Medicaid Services (2012). "Repetitive Transcranial Magnetic Stimulation (rTMS)". United States Department of Health and Human Services. Retrieved 2012-09-05.
(2) Centers for Medicare and Medicaid Services (2012-01-27). "Local Coverage Determination (LCD) for Repetitive Transcranial Magnetic Stimulation (rTMS) (L32228)". United States Department of Health and Human Services. Retrieved 2012-10-12.
(3) "Important Treatment Option for Depression Receives Medicare Coverage". Press Release. PBN.com: Providence Business News. 2012-03-30. Archived from the original on 2012-10-11. Retrieved 2012-10-11.
(4) "Transcranial Magnetic Stimulation Cites Influence of New England Comparative Effectiveness Public Advisory Council (CEPAC)". Berlin, Vermont: Central Vermont Medical Center. 2012-02-06. Archived from the original on 2012-10-12. Retrieved 2012-10-12.
- Novitas Solutions, Inc. (2012-08-20). "LCD L32752 - Transcranial Magnetic Stimulation for Depression". Contractor's Determination Number L32752. Novitas Solutions. Retrieved 2012-10-12.
- (1) "Guidance: Transcranial magnetic stimulation for severe depression (IPG242)". NICE interventional procedure guidance, issued November 2007. National Institute for Health and Clinical Excellence. Archived from the original on 2012-11-27. Retrieved 2012-11-27.
(2) "Transcranial magnetic stimulation for severe depression (IPG242)". National Institute for Health and Clinical Excellence. 2011-03-04. Archived from the original on 2012-11-27. Retrieved 2012-11-27.
- American Medical Association (2012). "Current Procedural Terminology". American Medical Association. Retrieved 2012-02-02.
- Cacioppo, JT; Tassinary, LG; Berntson, GG., ed. (2007). Handbook of psychophysiology (3rd ed.). New York, NY: Cambridge Univ. Press. p. 121. ISBN 0-521-84471-1.
- "Brain Stimulation Therapies". National Institute of Mental Health. 2009-11-17. Retrieved 2010-07-14.
- (1) Zangen, A.; Roth, Y.; Voller, B.; Hallett, M. (2005). "Transcranial magnetic stimulation of deep brain regions: Evidence for efficacy of the H-Coil". Clinical Neurophysiology 116 (4): 775–779. doi:10.1016/j.clinph.2004.11.008. PMID 15792886.
(2) Huang, YZ; Sommer, M; Thickbroom, G; Hamada, M; Pascual-Leonne, A; Paulus, W; Classen, J; Peterchev, AV; Zangen, A; Ugawa, Y (2009). "Consensus: New methodologies for brain stimulation". Brain Stimulation 2 (1): 2–13. doi:10.1016/j.brs.2008.09.007. PMID 20633398.
- Riehl M (2008). "TMS Stimulator Design". In Wassermann EM, Epstein CM, Ziemann U, Walsh V, Paus T, Lisanby SH. Oxford Handbook of Transcranial Stimulation. Oxford: Oxford University Press. pp. 13–23, 25–32. ISBN 0-19-856892-4.
- Roth, BJ; MacCabee, PJ; Eberle, LP; Amassian, VE; Hallett, M; Cadwell, J; Anselmi, GD; Tatarian, GT (1994). "In vitro evaluation of a 4-leaf coil design for magnetic stimulation of peripheral nerve". Electroencephalography and Clinical Neurophysiology/Evoked Potentials Section 93: 68. doi:10.1016/0168-5597(94)90093-0. PMID 7511524.
- Wassermann, EM; Epstein, CM; Ziemann, U; Walsh, V; Paus, T; Lisanby, SH (2008). Oxford Handbook of Transcranial Stimulation (Oxford Handbooks). Oxford University Press, USA. ISBN 0-19-856892-4.
- Freeston, I; Barker, A (2007). "Transcranial magnetic stimulation". Scholarpedia 2 (10): 2936. doi:10.4249/scholarpedia.2936.
|Wikimedia Commons has media related to Transcranial magnetic stimulation.|