Neurogenic pain relief by repetitive transcranial magnetic cortical stimulation depends on the origin and the site of pain

Objective: Drug resistant neurogenic pain can be relieved by repetitive transcranial magnetic stimulation (rTMS) of the motor cortex. This study was designed to assess the influence of pain origin, pain site, and sensory loss on rTMS efficacy. Patients and methods: Sixty right handed patients were included, suffering from intractable pain secondary to one of the following types of lesion: thalamic stroke, brainstem stroke, spinal cord lesion, brachial plexus lesion, or trigeminal nerve lesion. The pain predominated unilaterally in the face, the upper limb, or the lower limb. The thermal sensory thresholds were measured within the painful zone and were found to be highly or moderately elevated. Finally, the pain level was scored on a visual analogue scale before and after a 20 minute session of "real" or "sham" 10 Hz rTMS over the side of the motor cortex corresponding to the hand on the painful side, even if the pain was not experienced in the hand itself. Results and discussion: The percentage pain reduction was significantly greater following real than sham rTMS (−22.9% v −7.8%, p = 0.0002), confirming that motor cortex rTMS was able to induce antalgic effects. These effects were significantly influenced by the origin and the site of pain. For pain origin, results were worse in patients with brainstem stroke, whatever the site of pain. This was consistent with a descending modulation within the brainstem, triggered by the motor corticothalamic output. For pain site, better results were obtained for facial pain, although stimulation was targeted on the hand cortical area. Thus, in contrast to implanted stimulation, the target for rTMS procedure in pain control may not be the area corresponding to the painful zone but an adjacent one. Across representation plasticity of cortical areas resulting from deafferentation could explain this discrepancy. Finally, the degree of sensory loss did not interfere with pain origin or pain site regarding rTMS effects. Conclusion: Motor cortex rTMS was found to result in a significant but transient relief of chronic pain, influenced by pain origin and pain site. These parameters should be taken into account in any further study of rTMS application in chronic pain control.

[1]  Á. Pascual-Leone,et al.  Reorganization of human cortical motor output maps following traumatic forearm amputation , 1996, Neuroreport.

[2]  Philippe Decq,et al.  Chronic motor cortex stimulation in the treatment of central and neuropathic pain. Correlations between clinical, electrophysiological and anatomical data , 1999, PAIN.

[3]  P Brugières,et al.  Motor cortex stimulation in the treatment of central and neuropathic pain. , 2000, Archives of medical research.

[4]  T Hirayama,et al.  Chronic motor cortex stimulation in patients with thalamic pain. , 1993, Journal of neurosurgery.

[5]  H. Tsuji,et al.  Direct and indirect activation of human corticospinal neurons by transcranial magnetic and electrical stimulation , 1996, Neuroscience Letters.

[6]  P Mertens,et al.  Electrical stimulation of motor cortex for pain control: a combined PET-scan and electrophysiological study , 1999, PAIN.

[7]  N Birbaumer,et al.  Reorganization of Motor and Somatosensory Cortex in Upper Extremity Amputees with Phantom Limb Pain , 2001, The Journal of Neuroscience.

[8]  K Kaneko,et al.  The effect of current direction induced by transcranial magnetic stimulation on the corticospinal excitability in human brain. , 1996, Electroencephalography and clinical neurophysiology.

[9]  J. Lefaucheur,et al.  Pain relief induced by repetitive transcranial magnetic stimulation of precentral cortex , 2001, Neuroreport.

[10]  M Hallett,et al.  Rapid reversible modulation of human motor outputs after transient deafferentation of the forearm , 1992, Neurology.

[11]  Ziad Nahas,et al.  A controlled trial of daily left prefrontal cortex TMS for treating depression , 2000, Biological Psychiatry.

[12]  V. Tronnier,et al.  Chronic precentral stimulation in trigeminal neuropathic pain , 2005, Acta Neurochirurgica.

[13]  Mark Hallett,et al.  Locating the Motor Cortex on the MRI with Transcranial Magnetic Stimulation and PET , 1996, NeuroImage.

[14]  J. Dejerine Le syndrome thalamique , 1906 .

[15]  H. Sackeim,et al.  Sham TMS: intracerebral measurement of the induced electrical field and the induction of motor-evoked potentials , 2001, Biological Psychiatry.

[16]  M. Fujii,et al.  [Motor cortex stimulation therapy in patients with thalamic pain]. , 1997, No shinkei geka. Neurological surgery.

[17]  U. Lindblom,et al.  Motor cortex stimulation as treatment of trigeminal neuropathic pain. , 1993, Acta neurochirurgica. Supplementum.

[18]  P. Rossini,et al.  Non-invasive electrical and magnetic stimulation of the brain, spinal cord and roots: basic principles and procedures for routine clinical application. Report of an IFCN committee. , 1994, Electroencephalography and clinical neurophysiology.

[19]  Á. Pascual-Leone,et al.  Rapid-rate transcranial magnetic stimulation of left dorsolateral prefrontal cortex in drug-resistant depression , 1996, The Lancet.

[20]  R. Peyron,et al.  Precentral Cortex Stimulation for the Treatment of Central Neuropathic Pain , 2000, Stereotactic and Functional Neurosurgery.

[21]  J. Lefaucheur,et al.  Interventional neurophysiology for pain control: duration of pain relief following repetitive transcranial magnetic stimulation of the motor cortex , 2001, Neurophysiologie Clinique/Clinical Neurophysiology.

[22]  J. Nguyen,et al.  Treatment of deafferentation pain by chronic stimulation of the motor cortex: report of a series of 20 cases. , 1997, Acta neurochirurgica. Supplement.

[23]  J. Lefaucheur,et al.  The antalgic efficacy of chronic motor cortex stimulation is related to sensory changes in the painful zone. , 2002, Brain : a journal of neurology.

[24]  M Hallett,et al.  Mood improvement following daily left prefrontal repetitive transcranial magnetic stimulation in patients with depression: a placebo-controlled crossover trial. , 1997, The American journal of psychiatry.

[25]  J P Malin,et al.  Cortical reorganization in patients with facial palsy , 1997, Annals of neurology.

[26]  B. Pleger,et al.  Assessment of reorganization in the sensorimotor cortex after upper limb amputation , 2001, Clinical Neurophysiology.

[27]  T Hirayama,et al.  Chronic motor cortex stimulation for the treatment of central pain. , 1991, Acta neurochirurgica. Supplementum.

[28]  Simon C Gandevia,et al.  Transcranial magnetic stimulation (TMS) in controlled treatment studies: are some “sham” forms active? , 2000, Biological Psychiatry.

[29]  A I Basbaum,et al.  Endogenous pain control systems: brainstem spinal pathways and endorphin circuitry. , 1984, Annual review of neuroscience.

[30]  P. Comte Monopolar versus bipolar stimulation. , 1982, Applied neurophysiology.

[31]  J. Bomanji,et al.  Comparison of 99mTc Infecton imaging with radiolabelled white-cell imaging in the evaluation of bacterial infection , 1996, The Lancet.

[32]  G. Wittenberg,et al.  Stimulation-Induced Within-Representation and Across-Representation Plasticity in Human Motor Cortex , 2002, The Journal of Neuroscience.