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© 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved., A group of European experts was commissioned to establish guidelines on the therapeutic use of repetitive transcranial magnetic stimulation (rTMS) from evidence published up until March 2014, regarding pain, movement disorders, stroke, amyotrophic lateral sclerosis, multiple sclerosis, epilepsy, consciousness disorders, tinnitus, depression, anxiety disorders, obsessive-compulsive disorder, schizophrenia, craving/addiction, and conversion. Despite unavoidable inhomogeneities, there is a sufficient body of evidence to accept with level A (definite efficacy) the analgesic effect of high-frequency (HF) rTMS of the primary motor cortex (M1) contralateral to the pain and the antidepressant effect of HF-rTMS of the left dorsolateral prefrontal cortex (DLPFC). A Level B recommendation (probable efficacy) is proposed for the antidepressant effect of low-frequency (LF) rTMS of the right DLPFC, HF-rTMS of the left DLPFC for the negative symptoms of schizophrenia, and LF-rTMS of contralesional M1 in chronic motor stroke. The effects of rTMS in a number of indications reach level C (possible efficacy), including LF-rTMS of the left temporoparietal cortex in tinnitus and auditory hallucinations. It remains to determine how to optimize rTMS protocols and techniques to give them relevance in routine clinical practice. In addition, professionals carrying out rTMS protocols should undergo rigorous training to ensure the quality of the technical realization, guarantee the proper care of patients, and maximize the chances of success. Under these conditions, the therapeutic use of rTMS should be able to develop in the coming years.

Objective To compare the efficacy of two different modalities of rTMS (20 Hz and Theta-Burst) in relieving chronic neuropathic pain. Methods Thirty patients (mean age 55 ± 12) suffering from drug-resistant neuropathic pain received 20 Hz and Theta-Burst rTMS in randomized order. For each modality, every patient received one week of stimulation (daily sessions on 5 consecutive days), the two sessions being separated by a month. Patients rated different aspects of their pain (intensity, unpleasantness, sleep disturbances, etc) on a daily basis, using a numerical rating scale (NRS), one week before (baseline), during and for 2 weeks after the end of each stimulation week. Each week’s ratings were averaged and compared to each other. Results This preliminary analysis takes account exclusively of the ‘intensity’ pain scores. In these first 30 patients, only 20 Hz rTMS lead to a significant decrease of the NRS, compared to baseline, during the two weeks following stimulation onset. Conclusions 20 Hz rTMS appears superior to Theta-Burst for chronic neuropathic pain relief. The study will be running until 40 consecutive patients are studied.

Objective The persistence of both early cortical responses (N20, Pa) and late associative potentials (vertex potentials, N100) has been shown to improve the probability of return to consciousness of comatose patients. However, the prognostic value of late responses without early cortical potentials has not been documented. Methods We report results in 5 comatose patients in whom late N100 responses could be recorded in the absence of reproducible early cortical auditory and/or somatosensory potentials. The etiologies of coma were: anoxic–ischemic after cardiopulmonary arrest (3), brainstem hemorrhage (1) and ischeamic stroke (1). Results All patients showed reproducible N100 waves but absence of early cortical auditory and/or somatosensory responses. The EEG was non-reactive in 3 patients. All 5 patients had a poor clinical outcome, toward either death or vegetative state. Discussion The presence of N100 wave without previous recordable potentials may be explained either by alternative parallel pathways, or by re-synchronization of an altered ascending volley. Whatever the explanation, the presence of N100 wave may be associated with a good neurological outcome only if preceded by early cortical potentials (Pa and N20), but not if early responses are absent. Key message Caution should be exerted in interpreting the prognostic value of the N100 wave alone.