Cortical Mapping in Conventional and High Dose Spinal Cord Stimulation: An Exploratory Power Spectrum and Functional Connectivity Analysis With Electroencephalography

• Published in: Neuromodulation (Malden, Mass.) Vol. 23; no. 1; pp. 74 - 81
• Main Authors: Goudman, Lisa, Linderoth, Bengt, Nagels, Guy, Huysmans, Eva, Moens, Maarten
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01.01.2020; Elsevier Limited
• Subjects: Aged; Brain Mapping - methods; Cerebral cortex; Cerebral Cortex - physiopathology; EEG; Electroencephalography; Electroencephalography - methods; Failed Back Surgery Syndrome; Failed Back Surgery Syndrome - physiopathology; Failed Back Surgery Syndrome - therapy; Female; High Dose SCS; Humans; Male; Medicin och hälsovetenskap; Middle Aged; Nerve Net - physiopathology; Neural networks; Pain Measurement - methods; Patients; Spinal cord; Spinal Cord Stimulation; Spinal Cord Stimulation - methods; supraspinal mechanisms; Surgery; Theta rhythms; High Dose SCS; Spinal Cord Stimulation; Electroencephalography; Failed Back Surgery Syndrome; supraspinal mechanisms
• ISSN: 1094-7159; 1525-1403; 1525-1403
• DOI: 10.1111/ner.12969

Objectives Spinal cord stimulation (SCS) is considered an effective pain‐relieving treatment for patients with Failed Back Surgery Syndrome (FBSS). Despite the clinical effectiveness, it is unknown whether the altered functional connectivity in such patients, as compared to healthy persons, can be influenced by SCS. Therefore, the goal of this study is to evaluate whether brain connectivity assessed by EEG differs between baseline and SCS in patients with FBSS. Materials and Methods Eight patients with FBSS underwent a resting‐state EEG protocol before SCS, 1.5 months and 2.5 months after receiving SCS. At each frequency band, power spectrums were compared for no SCS, conventional (CON) SCS and High Dose (HD) SCS. Functional connectivity, with the aid of eConnectome was also calculated. Results Significant differences in the average power density spectrum over the whole scalp were observed between no SCS, CON SCS and HD SCS in delta, theta and beta frequency bands (p < 0.01). The average power spectrum for CON SCS was significantly lower than the average power spectrum for HD SCS. Marked increases in strength of the information flow between electrode pair FC3‐TP9 in the beta frequency band (p = 0.006) were found in favor of HD SCS. Conclusions The differences in power spectrum and connectivity between the three conditions lead to the hypothesis that HD SCS differs from CON SCS on average power spectrum, suggesting that HD SCS may have a higher contribution on the excitatory bottom‐up pathway.