The effects of frequency in treating neuropathic pain using transcranial magnetic stimulation / 中华物理医学与康复杂志

ABSTRACT

Objective:To compare the effects of repetitive transcranial magnetic stimulation (TMS) at three different relatively high frequencies on neuropathic pain so as to find the best frequency.Methods:One hundred Sprague-Dawley rats were randomly divided into a sham operation group, a model group, a TMS group and a control stimulation group. The TMS group was further divided into a 5Hz group, a 10Hz group, and a 20Hz group. The rats in the model, control stimulation and TMS groups received constriction injury of the sciatic nerve, while the rats in the sham group were given a sham version of the operation. On the third day after the operation the rats in the TMS group and the control stimulation group began to receive TMS treatment. Neuropatic pain was evaluated on the day before the operation, and on the 3rd, 5th, 7th, 10th and 12th days after the operation. The evaluations included the paw withdrawal thermal latency (PWTL) and the paw withdrawal mechanical threshold (PWMT).Results:The average PWTLs and PWMTs in all of the TMS groups increased with the TMS treatment. Those of the 10Hz and 20Hz groups were significantly higher than the 5Hz group′s average, while there were no significant differences between the 10Hz group and 20Hz group.Conclusions:High-frequency TMS at different frequencies has different effects on neuropathic pain, at least in rats. The treatment efficacy at 10 and 20Hz is superior to that at 5Hz.