gms | German Medical Science

Objective: Chronic neuropathic disorders remain difficult to treat. Analgesic medication often achieves only an insufficient effect, therefore other non-pharmacological treatment has to be considered. One option for management of intractable pain is stimulation of the motor cortex by implantation of an epidural electrode. This effect of invasive stimulation could be replaced by transcranial magnetic stimulation. The objective of the study was to observe the pain reducing effect of non-invasive transcranial magnetic stimulation (rTMS) in patients suffering from different types of chronic neuropathic pain.

Method: The study was prospective. We included patients suffering from chronic pain syndromes, such chronic facial pain, poststroke pain, phantom pain and FBSS. The corresponding primary motor cortex was stimulated with high-frequent, repetitive transcranial magnetic stimulation (rTMS). Stimulation was repeated daily. The individual pain level was assessed by the visual analogue scale (VAS) and documented daily for three weeks. The first follow-up was done after 6 weeks.

Results: We included 45 patients (24 female / 21 male) between 31 and 78 years of age. The follow-up was done after at least six weeks, further intervals were determined individually with a maximum follow-up time of 4 years. A pain reduction in terms of a decrease in the VAS scale was obtained in 58% of patients over all groups, ranging from 2 to 8 points on VAS with a mean value of 3,6. Regarding the etiology of pain we observe a responding rate of 72% in the facial pain group, 40% in the poststroke pain group, 25% in the FBSS group and no response in the phantom pain group. The pain reduction occurred with a delay between 4 days and 3 weeks, and showed a long-term effect up to 10 months.

Conclusions: Non-invasive transcranial magnetic stimulation seems to be applicable for neuropathic pain syndromes. In chronic facial pain we could observe a higher response rate than in any other chronic pain syndrome. Pain reduction has a long-term effect, which outlast the stimulation period.