Time course of the response to navigated repetitive transcranial magnetic stimulation at 10 Hz in chronic neuropathic pain.

Objective This prospective study evaluated the time to response and outcomes of navigated repetitive transcranial magnetic stimulation (TMS) at a frequency of 10 Hz in patients with chronic neuropathic pain. Methods This prospective study included patients with unilateral chronic neuropathic pain. All patients received motor cortex stimulation at 10 Hz over nine consecutive days using repetitive TMS. Outcome was evaluated over a six-week follow-up period using the visual analogue scale, the German Pain Questionnaire and time to pain reduction. Results Fifty patients (23 female, 27 male) were recruited. Two patients were excluded from analysis owing to premature discontinuation of treatment and follow-up. 31/48 patients in the cohort suffered from atypical facial pain. The pain duration ranged approximately from six months to 27 years. After six weeks, 28/46 patients reported a significant level of pain relief (P < 0.001). Conclusion Navigated repetitive TMS for chronic pain is a non-invasive modality with demonstrable clinical benefit. In particular, patients with atypical facial pain with a clear clinicoanatomical correlate responded well to high-frequency stimulation. Patients with a mean pain history of less than five years benefited significantly from this treatment, so early treatment with repetitive TMS should be encouraged.