什麼是頭顱磁刺激療法(Transcranial magnetic stimulation,簡稱TMS)?這是一種非侵入性治療,主要想造成腦細胞的超極化(hyperpolarization)或者是去極化的作用試圖達到效果,TMS是利用電磁的引導,造成磁場快速的轉變,引發微弱的電流,結果可能導致腦部某些特定區域的活動也可能有些微不適。目前使用比較多的的方式是重複性頭顱磁刺激療法(repetitive transcranial magnetic stimulation ,簡稱rTMS)。至於rTMS的確實作用機轉,目前還不清楚:


Fitzgerald PB; Fountain S; Daskalakis J (December 2006). "A comprehensive review of the effects of rTMS on motor cortical excitability and inhibition". Clinical Neurophysiology 117 (12): 2584–96. doi:10.1016/j.clinph.2006.06.712. PMID 16890483.


有危險性嗎?儘管這個療法經常被視為低危險性,但是仍有臨床上必須留心的副作用,包含癲癇發作及昏倒、頭痛、輕微認知改變以及精神症狀(特別是憂鬱症患者應該提防躁症發作風險,儘管被視為風險不高):


Rossi, S; et al. (2009). "The Safety of TMS Consensus Group, Safety, ethical considerations, and application guidelines for the use of transcranial magnetic stimulation in clinical practice and research" (pdf). Clinical Neurophysiology 120 (12): 2008–2039. doi:10.1016/j.clinph.2009.08.016. PMID 19833552. http://www.aipass.org/files/TMS_Safety,%20ethical%20considerations,%20and%20application%20guidelines.pdf.


已經發表的個案報告,有超過16個因為接受TMS導致癲癇發作的案例,在1998年安全指引出版之前有七個癲癇案例被提出來:


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" (pdf). Electroencephalography and clinical Neurophysiology 108 (1): 1–16. doi:10.1016/S0168-5597(97)00096-8. PMID 9474057. http://www.icts.uci.edu/neuroimaging/Wassermann_rTMS_Safety1998.pdf.

其他副作用包含頭皮因為刺激影響神經到神經及肌肉產生的不舒服或者疼痛:


"Transcranial Magnetic Stimulation (TMS)". National Alliance on Mental Illness. http://www.nami.org/Content/ContentGroups/Helpline1/Transcranial_Magnetic_Stimulation_(rTMS).htm. Retrieved 2008-12-15.


治療過程產生的機器生也會對聽覺造成影響,因為腦波電級不相容而導致電熱,嚴重的話甚至會皮膚灼傷:


 Roth BJ; Pascual-Leone A; Cohen LG; Hallett M (1992). "The heating of metal electrodes during rapid-rate magnetic stimulation: A possible safety hazard". Electroenceph. Clin. Neurophysiol. 85 (2): 116–123. doi:10.1016/0168-5597(92)90077-O. PMID 1373364.



 TMS作為憂鬱症治療的申請並不順利,在2007年一月美國食品藥物管理局(FDA)的諮詢委員會不同意把TMS作為憂鬱症治療的方式,在短期的治療中儘管看不到明顯的副作用(跟抗憂鬱劑比較),但跟藥物治療相比,TMS無法證明對憂鬱症患者有療效:


 Scudiero, JL (2007-01-26). "Brief Summary From the Neurological Devices Panel Meeting - January 26, 2007". FDA. http://www.fda.gov/AdvisoryCommittees/CommitteesMeetingMaterials/MedicalDevices/MedicalDevicesAdvisoryCommittee/NeurologicalDevicesPanel/ucm124779.htm. 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.”"


儘管如此,FDA在2008年還是有條件通過作為憂鬱症的治療,對象是那些用過抗憂鬱劑治療,無法達到滿意療效的人,可以考慮這種方式:


Melkerson, MN (2008-12-16). "Special Premarket 510(k) Notification for NeuroStar TMS Therapy System for Major Depressive Disorder" (pdf). FDA. http://www.accessdata.fda.gov/cdrh_docs/pdf8/K083538.pdf. Retrieved 2010-07-16.


然而在廠商使用說明上也強調說明,用TMS治療那些對抗憂鬱劑治療不滿意的憂鬱症患者,在臨床上的還無法提供證據證實可達滿意的治療效果,包含那些從未接受藥物治療的憂鬱症患者也一樣:


 NeuroStar TMS Therapy System User Manual. 1. Neuronetics, Inc.. pp. 1–5. http://www.neuronetics.com/pdf/Prescribing%20Information.pdf. Retrieved 2010-09-13.


在2011年七月,FDA最新公告,把這套系統列為特別管控的的第二級醫療器材,醫療使用建議如下:


TMS是一種外用器材,在腦部區域傳遞電磁脈衝讓腦前額皮質細胞引發神經活動的電流來治療那些不會引發癲癇的憂鬱症患者,他們至少是試過一種抗憂鬱劑治療失敗且現在沒有用藥治療的狀況:



  1. 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. http://www.gpo.gov/fdsys/pkg/FR-2011-07-26/pdf/2011-18806.pdf. Retrieved 2011-08-11. 
  2. 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. http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/GuidanceDocuments/ucm265269.htm. Retrieved 2011-08-10.

目前仍有學者對於TMS是否能改善憂鬱症的效果感到懷疑,因為他們認定臨床的證據不足:


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. http://www.nature.com/npp/journal/v34/n8/pdf/npp200922a.pdf.


以上資料提供對TMS治療有興趣的人作參考。


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