[Central invasive neuromodulation for the treatment of chronic pain : Epidural motor cortex stimulation and deep brain stimulation].

BACKGROUND

Treatment of central neuropathic pain, such as pain after plexus avulsion, stroke or cerebral hemorrhage (central post-stroke pain; CPSP) or trigeminal neuropathies, is generally not possible with neuromodulation methods that are carried out further peripherally. Non-invasive neuromodulation methods only have a temporary effect. Permanently implanted electrodes subcortically (deep brain stimulation; DBS) or epi- or subdurally over the motor cortex ("motor cortex stimulation", MCS) can lead to pain relief in about 50-70% of patients with central neuropathic pain.

OBJECTIVES

To present the main indications for DBS and MCS according to the literature.

MATERIAL AND

METHODS

Both procedures, DBS and MCS, are not approved for the treatment of chronic pain, but decades of clinical experiences exist. The results of meaningful studies and clinical series are presented on the basis of a literature search and recommendations for specific indications are developed.

RESULTS

Patients with CPSP benefit significantly more from MCS than from DBS, and better results are also achieved with MCS in patients with neuropathic pain after spinal cord injury. Patients with pain after plexus avulsion or phantom pain can be treated better with DBS. The best results are achieved with both procedures in patients with trigeminal neuropathy. We prefer MCS as it is less invasive. The results from both stimulation therapies for postherpetic neuralgia are disappointing.

CONCLUSIONS

DBS and MCS can be used to treat chronic neuropathic pain when conservative or less invasive measures have failed. Depending on the cause and localization of the pain, DBS or MCS may have better long-term results. However, neither procedure is a "stand-alone" therapy; they are additive and must be accompanied by medication and behavioral therapy.