We present the case of a patient with neuropathic pain in whom neuromodulation via magnetic field exposure using the AT-04 achieved a decrease in his NRS score. This is the first clinical report of this effect in a patient with neuropathic pain. Recommended pharmacotherapies for neuropathic pain include gabapentinoids, serotonin noradrenaline reuptake inhibitors (SNRIs), and opioids, which can have the side effects of sedation, dizziness, nausea, vomiting, and constipation [6, 7]. Neuromodulation by electrical therapies such as TENS and SCS can alleviate neuropathic pain [1, 2] but is accompanied by uncomfortable pulsations and painful sensations. In addition to its analgesic effect, the AT-04 device has the advantage of producing no meaningful sensory discomfort in patients, which suggests its potential as a treatment option for patients with refractory neuropathic pain.

The detailed mechanisms underlying the analgesic effect of neuromodulation via magnetic field exposure using the AT-04 remain unclear. Kohno et al. reported an analgesic effect of the AT-04 by magnetic field exposure when it was applied in the vicinity of the spinal cord and abdomen as well as to the affected part of the body [4]. In the present case, magnetic fields generated by emitters placed around the patient’s umbilicus effectively decreased the NRS score of neuropathic pain in the patient’s left upper limb. A previous study has suggested that magnetic fields have the effect of activating cellular functions that promote regeneration and repair of peripheral sensory nerves [8] by activation of both the descending pain modulation system and the endogenous opioid analgesic system [4]. The range of the magnetic fields generated by the emitters placed around the patient’s umbilicus reached the whole body including the spinal cord and the left upper limb. Accordingly, we consider that neuromodulation through magnetic field exposure using the AT-04 might have relieved neuropathic pain in the present patient via the activation of both the descending pain modulation system and the endogenous opioid analgesic system.

There are some limitations in the present case report. First, we did not investigate whether the analgesic effect of neuromodulation through magnetic field exposure using the AT-04 would provide an additive effect on background pharmacotherapy in patients taking SNRIs and opioids. Second, we did not clarify the optimal time per session or frequency per day of magnetic field exposure using the AT-04. Third, in the present case, neuromodulation through magnetic field exposure using the AT-04 decreased the NRS score of neuropathic pain but did not lead to a reduction in dose of the pharmacological treatments.

We presented a case of neuropathic pain in which neuromodulation through magnetic field exposure using the AT-04 successfully decreased the patient’s NRS score. The AT-04 portable magnetic field-generating device has potential as a therapeutic option for refractory neuropathic pain.