Motor Cortex Stimulation
Motor cortex stimulation is performed to relieve intractable neuropathic pain, especially of the face e.g. trigeminal neuralgia. It is postulated that nerve injury prevents sensory neurons below the level of deafferentation from exerting their normal inhibitory effect on deafferented nociceptive neurons due to the development of aberrant connections.
In MCS, electrodes are placed epidurally rather than directly onto brain parenchyma, in contrast to thalamic or peri-aqueductal gray stimulation. Approximately half of patients experience lasting relief, which is similar to DBS, though possibly with fewer complications. Motor mapping is performed to localize and stimulate the exact region of cortex that represents the body part in pain. Theoretical “fourth order” sensory neurons may be excited to exert inhibition on nociceptive neurons.
- Jean-Paul Nguyen, Jean-Pascal Lefaucheur, Philippe Decq, Takuya Uchiyama, Alexandre Carpentier, Denis Fontaine, Pierre Brugières, Bernard Pollin, Annaick Fève, Sylvie Rostaing, et al. Chronic motor cortex stimulation in the treatment of central and neuropathic pain. Correlations between clinical, electrophysiological and anatomical data. Pain, Volume 82, Issue 3, 1 September 1999, Pages 245-251
- Tsubokawa T, Katayama Y, Yamamoto T, Hirayama T, Koyama S. Chronic motor cortex stimulation for the treatment of central pain. Acta Neurochir Suppl (Wien). 1991;52:137-9.