Applications of transcranial magnetic stimulation in migraine: evidence from a scoping review

Transcranial magnetic stimulation (TMS), a non-invasive brain stimulation method, is trying to emerge as a migraine management strategy for both attack treatment and prevention. This scoping review presents 16 among single-pulse (to manage episodic and chronic migraine) and repetitive TMS randomized clinical trials (to manage chronic migraine). The works we reviewed suggest that TMS may be adopted as add-on therapy in those patients who are refractory to pharmacological therapy only with special arrangements for individualized treatment strategies or research. There are still limited clinical research programs and metaanalysis to promote routinely TMS employment, as TMS has been shown either to have no significant effects for any outcome or to be effective for migraine. These diverging conclusions depend on several biasing factors, including the lack of reliable, large, sham-controlled clinical trials, the dyshomogeneity in study designs (including the area of stimulation, the frequency of stimulation, the number of pulses, pulse intensity, and the number of sessions), patient selection criteria (migraine w/o aura, episodic and chronic migraine; TMS contraindication), and the lack of outcomes homogeneity and long-term real-world efficacy data. Therefore, in the future, it will be important to conduct larger randomized trials to confirm TMS usefulness in migraine management (acute attack and prophylactic treatment), identify those patients who may benefit from TMS, maybe independently of pharmacological treatments (i.e., using TMS as an alternative and not only as an add-on treatment). Otherwise, TMS will play a role in treating migraine only with special arrangements for individualized management strategies or research.