Alteration of functional connectivity and network properties after stereo-electroencephalography guided radiofrequency thermocoagulation

Figures

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  Fig. 1. Epileptogenic zone exhibit significant change offunctional connectivityafter radiofrequency thermocoagulation (RF-TC). Across all patients, between connectivity and within connectivity evaluated by imaginary coherrence (iCoh) in epileptogenic zone (A and C) and non-epileptogenic zone (B and D) in different frequency bands. Bars represent the mean ± standard error of the mean between patients, t-test, *p < 0.05. Pre RF-TC, functional connectivity estimated before RF-TC; Post RF-TC, functional connectivity estimated after RF-TC

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  Fig. 2. Graph theory analysis of the modification of the functional connectivity after radiofrequency thermocoagulation (RF-TC). A-D: alteration of clustering coefficient, eigenvector centrality, edge betweenness and node betweenness after RF-TC procedure in different frequency bands independent of region of interest; E–F: modification of clustering coefficient, eigenvector centrality, edge betweenness and node betweenness after RF-TC procedure in different frequency bands in non-epileptogenic zone. Bars represent the mean ± standard error of the mean between patients, t-test, *p < 0.05. Pre RF-TC, functional connectivity estimated before RF-TC; Post RF-TC, functional connectivity estimated after RF-TC

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  Fig. 3. Betweennesscentrality map in an example patient demonstrating alteration of functional connectivity before (A) and after (B) radiofrequency thermocoagulation (RF-TC). 29 years old male patient with bilateral electrode placement. After RF-TC, the overall nodal betweenness centrality (size of sphere) and edge betweenness centrality (thickness of line connecting between 2 spheres) were relatively reducing. Alpha-band imaginary coherence is utilized for all measures. L, left; R, right; Ant, anterior; Post, posterior; STG.L, left superior temporal gyri; ITG.L, left inferior temporal gyri; BSTS.L, left bankssts; RMF.L left rostral middle frontal gyri; Ins.L left insular lobe; MOG.R, right medial orbitofrontal gyri; RAC.R, right rostral anterior cingulate

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  Fig. 4. Functional connectivity modification according to clinical response to radiofrequency thermocoagulation (RF-TC). A-C: changes of within connectivity, edge betweenness and node betweenness in patients with no clinical benefit in different frequency bands after RF-TC. D: alteration of clustering coefficient in patients with clinically improved. Bars represent the mean ± standard error of the mean between patients, t-test, *p < 0.05. Pre RF-TC, functional connectivity estimated before RF-TC; Post RF-TC, functional connectivity estimated after RF-TC

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  Fig. 5. The association between clinical response to radiofrequency thermocoagulation (RF-TC) and within connectivity in the different zones. Comparison between the difference between after and before values in clinically improved versus non-improved patients. Two-way analysis of variance (ANOVA) followed by Holm-Sidak correction, **p < 0.01, bars represent the mean ± standard error of the mean between patients. Impr, clinically improved after RF- TC; Not-impr, not clinically improved after RF- TC