Long-Term Results of Motor Cortex Stimulation in the Treatment of Chronic, Intractable Neuropathic Pain

Abstract

Background/Objectives: Although motor cortex stimulation (MCS) has been used for more than 20 years in the treatment of chronic neuropathic pain, there is still a debate about the efficacy of MCS. Methods: To investigate the long-term results and the factors associated with the long-term success of chronic MCS, 21 patients who underwent MCS trial were classified as having central poststroke pain, central pain after spinal cord injury (SCI) and peripheral neuropathic pain, and we investigated the clinical factors associated with long-term success and degree of pain relief. Results: Of the 21 patients, 16 (76.2%) had a successful trial and underwent chronic MCS. In the long-term follow-up (53 ± 39 months), only the diagnosis (central poststroke pain and peripheral neuropathic pain) was associated with long-term success defined as >30% pain relief compared with baseline (p < 0.05, χ² test). The difference in pain relief was not significant in patients having SCI pain (p > 0.05, 1-way ANOVA). The other variables did not show any significant influence in the long-term success and degree of pain relief (p > 0.05, 1-way ANOVA). Conclusions: MCS was more effective in the treatment of chronic neuropathic pain of central poststroke pain and peripheral neuropathic pain types than in the treatment of SCI pain in the long-term follow-up.

Long-term Effect and Predictive Factors of Motor Cortex and Spinal Cord Stimulation for Chronic Neuropathic Pain

“… 5) There have been several reports of the long-term effects of MCS with more than 3.5 years of follow-up. 14 , 26 – 28) Im et al examined 21 patients with neuropathic pain who underwent MCS, and reported that the trial success rate was 76.2%, with long-term effects achieved in 52.4% during 53 ± 39 months of follow-up. 26) These results are compatible with our current findings.…”

“… 14 , 26 – 28) Im et al examined 21 patients with neuropathic pain who underwent MCS, and reported that the trial success rate was 76.2%, with long-term effects achieved in 52.4% during 53 ± 39 months of follow-up. 26) These results are compatible with our current findings. Predictive factors associated with long-term effects of MCS are still unclear.…”

“…Several previous studies have reported that preoperative characteristics of patients such as the age, sex, and duration of pain, among others, were not related to the long-term outcomes. 14 , 26 – 28) However, the level of pain relief at 1 month after MCS system implantation was reported to be a strong predictor of long-term relief. 27) This result indicates that in the no long-term effect group, the initial pain relief might reflect the placebo effects.…”

The Effect of Motor Cortex Stimulation on Central Poststroke Pain in a Series of 16 Patients With a Mean Follow-Up of 28 Months

“…Andre‐Obadia et al reported that half of the patients in one study ( n = 10) showed a significant benefit after two to nine years of continuous MCS therapy. Im et al considered MCS to be more effective in the treatment of CPSP based on long‐term follow‐up (53 ± 39 months) compared to pain due to spinal cord injury. A loss of efficacy was reported based on long‐term follow‐up.…”

Long-Term Results of a Simultaneous Trial of Deep Brain and Motor Cortex Stimulation in Refractory Neuropathic Pain

“…The procedures for the simultaneous implantation of electrodes for DBS and MCS are described in detail in our previous reports regarding the surgical treatment of refractory neuropathic pain [16][17][18][19][20] . After we took stereotactic magnetic resonance images (MRI-Achieva 1.5T, Phillips, Eindhoven, the Netherlands), we transferred the obtained imaging data to the surgical navigation system, which was used to define the target coordinates of the Vc and the precentral hand knob (Figure 1a).…”