Analgesic Effect of Accelerated Repetitive Transcranial Magnetic Stimulation in Neuropathic Pain

Analgesic Effect of Accelerated Repetitive Transcranial Magnetic Stimulation in Pain Related to Peripheral Neuropathy

Peripheral neuropathy is a frequent condition, commonly associated with pain. Repetitive Transcranial Magnetic Stimulation (rTMS) is a noninvasive method of modulation of brain plasticity and is regarded as one of alternative methods to alleviate pain associated with various kind of neuropathies. rTMS is usually performed once a day and the whole therapy of neuropathic pain lasts one week. In a number of recent clinical trials including patients with depression and some other disorders, rTMS was delivered several times a day, which reduced the time of the whole therapy. This approach was termed an accelerated rTMS. The purpose of this study is to investigate feasibility of accelerated rTMS in treatment of neuropathic pain.

Peripheral neuropathy is a frequent condition, commonly associated with pain, which is often drug resistant. Repetitive Transcranial Magnetic Stimulation (rTMS) is a noninvasive method of modulation of brain plasticity. In this method, series of magnetic stimuli are delivered to the cerebral cortex, where they turn to electric current and depolarize repetitively the targeted neurons. If the stimulation is repeated during subsequent days it is capable to modify the activity of targeted cortical area for weeks or even months and by this way to achieve therapeutic effect. rTMS is most commonly used to treat drug-resistant depression but a number of other psychiatric and neurologic conditions is increasingly being regarded as therapeutic indication for rTMS. In patients suffering from neuropathic pain rTMS is delivered with high frequency, over primary motor areas (PMA). Stimulation of PMA should result in modulation of thalamic activity, achieved by antidromic excitation of thalamocortical connections. rTMS is usually performed once a day and the whole therapy of neuropathic pain lasts one week. In a number of recent clinical trials including patients with depression and some other disorders, rTMS was delivered several times a day, which reduced the time of the whole therapy. This approach was termed an accelerated rTMS. The purpose of this study is to investigate feasibility of accelerated rTMS in treatment of neuropathic pain.

Triple (Participant, Investigator, Outcomes Assessor). Sham stimulation will be provided by holding the stimulating coil perpendicularly to the scalp, which assures similar impression as during active stimulation but prevents significant magnetic field to reach the brain tissue.

10 hertz (Hz) rTMS will be administered over the primary motor area. Therapy will include 6 sessions (three sessions in two consecutive days). In every sessions 1500 magnetic pulses of 90% of the resting motor threshold intensity will be elicited.

Sham stimulation will mimic the active one except that the stimulating coil will be held perpendicularly to the scalp, which assures similar impression as the active stimulation but prevents that significant magnetic field will reach brain tissue.

High frequency rTMS over the primary motor area to induce the long term potentiation of primary motor areas for the muscles of upper extremity.

An analog scale of the length of 100 millimeter. Total score of 100, with higher scores representing more severe pain. Change from baseline score in the Visual Analogue Scale to the measurement taken after finishing rTMS.

An analog scale of the length of 100 millimeter. Total score of 100, with higher scores representing more severe pain. Change from baseline score in the Visual Analogue Scale to the measurement taken after two weeks after finishing rTMS.

An analog scale of the length of 100 millimeter. Total score of 100, with higher scores representing more severe pain. Change from baseline score in the Visual Analogue Scale to the measurement taken after four weeks after finishing rTMS.

Total score 10, with higher scores representing more severe pain. Change from baseline score in the Numeric Pain Severity Scale to the measurement taken after finishing rTMS.

Total score 10, with higher scores representing more severe pain. Change from baseline score in the Numeric Pain Severity Scale to the measurement taken two weeks after finishing rTMS.

Total score 10, with higher scores representing more severe pain. Change from baseline score in the Numeric Pain Severity Scale to the measurement taken after four weeks after finishing rTMS.

Total score 120, with higher scores representing more severe pain and other symptoms of neuropathy. Change from baseline score in the Neuropathic Pain Symptoms Inventory to the measurement taken after finishing rTMS.

Total score 120, with higher scores representing more severe pain and other symptoms of neuropathy. Change from baseline score in the Neuropathic Pain Symptoms Inventory to the measurement taken two weeks after finishing rTMS.

Total score 120, with higher scores representing more severe pain and other symptoms of neuropathy. Change from baseline score in the Neuropathic Pain Symptoms Inventory to the measurement taken four weeks after finishing rTMS.

Total score 24, with higher scores representing more severe insomnia. Change from baseline score in the Athens Insomnia Scale to the measurement taken after finishing rTMS.

Total score 24, with higher scores representing more severe insomnia. Change from baseline score in the Athens Insomnia Scale to the measurement taken two weeks after finishing rTMS.

Total score 24, with higher scores representing more severe insomnia. Change from baseline score in the Athens Insomnia Scale to the measurement taken four weeks after finishing rTMS.

Change from baseline strength of the foot extension to the measurement taken two weeks after finishing rTMS.

Change from baseline strength of the foot extension to the measurement taken four weeks after finishing rTMS.

Inclusion Criteria: Diagnosis of peripheral neuropathy Neuropathic pain of constant severity since not less than a month and requiring use of analgesics more than once a week Score of 30 millimeter or more on the 100 millimeter visual analog scale of pain intensity at inclusion Exclusion Criteria: Severe depression Personality disorders and other psychiatric conditions, which could disturb the participation in the study Cognitive deficits, which could disturb the participation in the study Epilepsy Presence of magnetic material in the reach of magnetic field Pregnancy Likelihood to get pregnant Intracranial electrodes

After completing the study, the age and gender of participants as well as the scores and results of all outcome measurements made at baseline, after rTMS, at the first and at the second follow-up will be made available to other researchers on request.