Quantitative EEG and neuromodulation for the treatment of central neuropathic pain in paraplegic patients

R Medicine (General);RZ Other systems of medicine

Hasan, Muhammad Abul ; Hasan, Hasan

University:University of Glasgow

Department:School of Engineering

关键词: Neurofeedback, Central Neuropathic Pain, EEG;   

Others  :  http://theses.gla.ac.uk/5567/1/2014HasanPhd.pdf

来源: University of Glasgow

【 摘 要 】

Approximately, 2/3 of patients with a spinal cord injury (SCI) suffer from chronic pain, leading to a reduction in quality of life. The prevalence of chronic central neuropathic pain (CNP) in the SCI population is 40%. Recent neuroimaging studies provided evidence that CNP is accompanied by modified brain activity at surface and deep cortical levels and that CNP is resistant to different pharmacological and non-pharmacological treatments. Our current knowledge on how CNP affects the brain activity of SCI patients is mainly based on fMRI studies. Although these studies provide precise spatial localisation of brain regions most affected by CNP, they indirectly measure brain activity through measuring blood oxygenation. Therefore they lack information specific to neuronal activity such as dynamic, time and frequency dependant oscillatory activity of cortical structures. Therefore, in Phase 1 of this study, electroencephalogram (EEG) activity of paraplegic patients with CNP (PWP) is compared with the EEG activity of able-bodied (AB) participants and paraplegic patients without CNP (PNP). It was found that CNP leads to frequency dependant EEG signatures both in the relaxed state and during motor tasks that are not restricted to the cortical representation of the body part perceived as being painful.The pharmacological treatment of CNP has a number of side effects and does not provide significant pain relief. The effect of non-pharmacological treatments is inconsistent. Neurofedback (NF) is a non-pharmacological treatment, based on the voluntarily modulation of brain activity to control pain intensity. Using NF training the patient can learn and apply a mental strategy to control pain, without the need for an external device. However, NF requires a large number of training sessions to learn the necessary mental strategy. Therefore, in Phase 2 of this study, the effect on pain intensity of a large number of NF sessions, using different NF training protocols, was assessed. The clinically and statistically significant reduction of pain observed in this study demonstrates that NF training has the potential to manage chronic CNP in paraplegic patients. This study also provides evidence that the reduction of pain achieved using NF training may not be due to a placebo effect. Furthermore, the study demonstrates the immediate global effect of NF training on power and coherence. To date, no neuroimaging studies that have applied NF training with patients with CNP have shown changes in brain activity before the first and after the last training session. Therefore, in phase 3 of this study, the long-term neurological effect of NF training was assessed using EEG. This study provides evidence that NF training does not only induce an effect on spontaneous EEG activity, but also induces changes on evoked EEG activity. In conclusion, this study compared the EEG activity of three groups (AB, PWP, and PNP) and found that CNP (PWP group) leads to frequency dependant dynamic oscillatory signatures. The study also reported that NF training has a potential to reduce pain and this reduction of pain might not be an effect of placebo. Furthermore, it was found that NF training induce long-term changes in the EEG activity recorded in relaxed state and during motor tasks. This long-term change in EEG activity was noticed at the surface and deep cortical structures.