Long-term follow-up of motor cortex stimulation on central poststroke pain in thalamic and extrathalamic stroke

Objective To investigate the long-term effects of motor cortex stimulation (MCS) on central poststroke pain (CPSP) in patients with thalamic and extrathalamic stroke. Materials and Methods We retrospectively analyzed 21 cases of CPSP patients who were treated with MCS. Pain intensity was evaluated using the visual analog scale (VAS) and Neuropathic Pain Symptom Inventory (NPSI) before the operation and at follow-up assessments. Sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI). Results The average follow-up time was 65.43 +/- 26.12 months. In the thalamus stroke group (n = 11), the mean preoperative VAS score was 8.18 +/- 0.75 and the final mean follow-up VAS score was 4.0 +/- 2.14. The mean total NPSI score at the last follow-up (20.45 +/- 12.7) was significantly reduced relative to the pre-MCS score (30.27 +/- 8.97, p < 0.001). Similarly, the mean PSQI value at the last follow-up (12.63 +/- 1.91) was significantly reduced compared with the pre-MCS value (16.55 +/- 1.97, p < 0.001). In the extrathalamic stroke group (n = 11), the mean preoperative VAS score was 8.2 +/- 0.79 and the final mean follow-up VAS score was 6.6 +/- 2.12. The mean total NPSI score before MCS was not statistically different from that at the last follow-up. There were no statistical differences in sleep quality before versus after surgery. Conclusion Motor cortex stimulation has higher long-term efficacy in CPSP patients with stroke confined to the thalamus than in CPSP patients with stroke involving extrathalamic structures.