Recovery of Pain Control by Intensive Reprogramming after Loss of Benefit from Motor Cortex Stimulation for Neuropathic Pain
- 1 January 2004
- journal article
- research article
- Published by S. Karger AG in Stereotactic and Functional Neurosurgery
- Vol. 82 (5-6), 207-213
- https://doi.org/10.1159/000082447
Abstract
Motor cortex stimulation (MCS) may serve as an adjunct in managing neuropathic pain after other conservative and interventional methods have failed. However, the magnitude and duration of the benefit are highly variable, with a significant percentage of patients losing pain relief over time. We investigated whether intensive reprogramming could recapture the beneficial effects of MCS. Six patients who had previously undergone MCS implantation for neuropathic pain but had lost benefit were brought back for 1-5 days of intensive reprogramming. Four patients were evaluated as inpatients while the others were seen as outpatients during multiple visits over several days. Several hours a day were spent with each patient. Patients completed visual analog scale (VAS) ratings at intervals throughout the reprogramming period to judge effectiveness of stimulation. Pre- and postadjustment VAS were compared using a paired t test. The patients' average age was 50 years (range 26-71). The diagnoses were trigeminal neuropathic pain (2 patients), complex regional pain syndrome I (2), phantom limb pain (1) and poststroke pain (1). The mean duration of pain was 6 years. The MCS benefit had initially lasted for a mean of 7.16 months (range 2-18 months). After reprogramming, 5 of 6 patients experienced improvement in pain. Average VAS scores decreased from 7.44 to 2.28 (p < 0.001) in those patients who responded to reprogramming. The average stimulation parameters in these patients were 5 V amplitude (range 1.7-10), 313 micros pulse width (range 240-390) and frequency of 84 Hz (range 55-130). Three patients experienced seizures during reprogramming. The mean seizure threshold was 8.9 V. No patient experienced seizures at their therapeutic settings. Pain control has been maintained after discharge. Intensive reprogramming can recapture the benefit of MCS in patients who have lost pain control. The use of broad dipoles using two contacts rather than one contact of the 1 x 4 electrode array improved the ability to recapture beneficial stimulation. There is a significant risk of seizures during aggressive reprogramming.Keywords
This publication has 12 references indexed in Scilit:
- Improvement and Decline in Tactile Discrimination Behavior after Cortical Plasticity Induced by Passive Tactile CoactivationJournal of Neuroscience, 2004
- Precentral stimulation for chronic painNeurosurgery Clinics of North America, 2003
- Motor cortex stimulation in patients with post-stroke pain: Conscious somatosensory response and pain controlNeurological Research, 2003
- The antalgic efficacy of chronic motor cortex stimulation is related to sensory changes in the painful zoneBrain, 2002
- Motor Cortex Stimulation for Phantom Limb Pain: Comprehensive Therapy with Spinal Cord and Thalamic StimulationStereotactic and Functional Neurosurgery, 2001
- Chronic Motor Cortex Stimulation for Phantom Limb Pain: Correlations between Pain Relief and Functional Imaging StudiesStereotactic and Functional Neurosurgery, 2001
- Electrical stimulation of motor cortex for pain control: a combined PET-scan and electrophysiological studyPain, 1999
- Chronic precentral stimulation in trigeminal neuropathic painActa Neurochirurgica, 1996
- Phantom-limb pain as a perceptual correlate of cortical reorganization following arm amputationNature, 1995
- Chronic Motor Cortex Stimulation for the Treatment of Central PainPublished by Springer Science and Business Media LLC ,1991