|
Academic Journal
PAIN MANAGEMENT
| Title: |
Repetitive Transcranial Magnetic Stimulation is Efficacious as an Add-On to Pharmacological Therapy in Complex Regional Pain Syndrome (CRPS) Type I
| | Date: | April 29, 2010 | | Author(s): |
Helder Picarelli, Manoel Jacobsen Teixeira, Daniel Ciampi de Andrade,
Martin Luiz Myczkowski, Tatiana Barreira Luvisotto, Lin Tchia Yeng,
Erich Talamoni Fonoff, Saxby Pridmore, and Marco Antonio Marcolin
| | Source: | The Journal of Pain 2010 | | Keywords: |
rTMS - Capsaicin - Pain - DLPFC - Motor cortical excitability - Intracortical inhibition - Intracortical facilitation
| | Abstract: |
Single-session repetitive transcranial magnetic stimulation (rTMS) of the motor cortex (M1) is effective in the treatment of chronic pain patients, but the analgesic effect of repeated sessions is still unknown. We evaluated the effects of rTMS in patients with refractory pain due to complex regional pain syndrome (CRPS) type I. Twenty-three patients presenting CRPS type I of 1 upper limb were treated with the best medical treatment (analgesics and adjuvant medications, physical therapy) plus 10 daily sessions of either real (r-) or sham (s-) 10Hz rTMS to the motor cortex (M1). Patients were assessed daily and after 1 week and 3 months after the last session using the Visual Analogical Scale (VAS), the McGill Pain Questionnaire (MPQ), the Health Survey-36 (SF-36), and the Hamilton Depression (HDRS). During treatment there was a significant reduction in the VAS scores favoring the r-rTMS group, mean reduction of 4.65 cm (50.9%) against 2.18 cm (24.7%) in the s-rTMS group. The highest reduction occurred at the tenth session and correlated to improvement in the affective and emotional subscores of the MPQ and SF-36. Real rTMS to the M1 produced analgesic effects and positive changes in affective aspects of pain in CRPS patients during the period of stimulation
Perspective: This study shows an efficacy of repetitive sessions of high-frequency rTMS as an add-on therapy to refractory CRPS type I patients. It had a positive effect in different aspects of pain (sensory-discriminative and emotional-affective). It opens the perspective for the clinical use of this technique.
|
 Back to top
| | Title: |
Repetitive transcranial magnetic stimulation (rTMS) of the dorsolateral prefrontal cortex (DLPFC) during capsaicin-induced pain: modulatory effects on motor cortex excitability.
| | Date: | March 16, 2010 | | Author(s): |
Fierro B, De Tommaso M, Giglia F, Giglia G, Palermo A, Brighina F.
| | Source: | Exp Brain Res. | | Keywords: |
rTMS - Capsaicin - Pain - DLPFC - Motor cortical excitability - Intracortical inhibition - Intracortical facilitation
| | Abstract: |
Evidence by functional imaging studies suggests the role of left DLPFC in the inhibitory control of nociceptive transmission system. Pain exerts an inhibitory modulation on motor cortex, reducing MEP amplitude, while the effect of pain on motor intracortical excitability has not been studied so far. In the present study, we explored in healthy subjects the effect of capsaicin-induced pain and the modulatory influences of left DLPFC stimulation on motor corticospinal and intracortical excitability. Capsaicin was applied on the dorsal surface of the right hand, and measures of motor corticospinal excitability (test-MEP) and short intracortical inhibition (SICI) and facilitation (ICF) were obtained by paired-pulse TMS on left motor cortex. Evaluations were made before and at different times after capsaicin application in two separate sessions: without and with high-frequency rTMS of left DLPF cortex, delivered 10 min. after capsaicin application. We performed also two control experiments to explore: 1: the effects of Left DLPFC rTMS on capsaicin-induced pain; 2: the modulatory influence of left DLPFC rTMS on motor cortex without capsaicin application. Capsaicin-induced pain significantly reduced test MEP amplitude and decreased SICI leaving ICF unchanged. Left DLPFC rTMS, together with the analgesic effect, was able to revert the effects of capsaicin-induced pain on motor cortex restoring normal MEP and SICI levels. These data support the notion that that tonic pain exerts modulatory influence on motor intracortical excitability; the activation of left DLPFC by hf rTMS could have analgesic effects, reverting also the motor cortex excitability changes induced by pain stimulation.
|
Back to top
| | Title: |
Motor cortex rTMS reduces acute pain provoked by laser stimulation in patients with chronic neuropathic pain
| | Date: | 2010 | | Author(s): |
Jean-Pascal Lefaucheur a,b,*, Gilbert Jarry a,b, Xavier Drouot a,b, Isabelle Ménard-Lefaucheur a, Yves Keravel c, Jean-Paul Nguyen c
| | Source: | Clinical Neurophysiology | | Keywords: |
Laser-evoked potentials
Motor cortex
Neuropathic pain
Provoked pain
Transcranial magnetic stimulation
| | Abstract: |
Objective: To assess the modulation of acute provoked pain by repetitive transcranial magnetic stimulation
(rTMS) of the motor cortex in patients with chronic neuropathic pain.
Methods: In 32 patients with chronic neuropathic pain affecting one upper limb, laser-evoked potentials
(LEPs) (N2 and P2 components) were recorded in response to laser stimulation of the painful or painless
hand, before and after active or sham rTMS applied at 10 Hz over the motor cortex corresponding to the
painful hand. Laser-induced pain was scored on a visual analogue scale.
Results: Both active and sham rTMS reduced N2–P2 amplitude of the LEPs in response to painful or painless
hand stimulation, likely due to the decline of attention during the sessions. However, active rTMS,
but not sham rTMS, specifically reduced N2 amplitude and N2/P2 amplitude ratio of the painful hand
LEPs. Painful hand LEP attenuation correlated with the magnitude of pain relief produced by active rTMS.
Conclusion: Motor cortex rTMS delivered at high frequency (10 Hz) was able to reduce LEP amplitude in
parallel with laser-induced pain scores in patients with chronic neuropathic pain. The preferential change
in the N2 component suggested a modulation of the sensori-discriminative aspect of laser-induced pain.
Significance: Previous studies have shown that rTMS delivered to various cortical targets by different protocols
could modulate experimental pain, primarily in healthy subjects. The present results demonstrate
the ability of motor cortex rTMS to interfere with the processing of acute provoked pain, even if there is
an underlying chronic neuropathic pain.
|
Back to top
|
|