Limits...
EEG Source Imaging in Partial Epilepsy in Comparison with Presurgical Evaluation and Magnetoencephalography.

Park CJ, Seo JH, Kim D, Abibullaev B, Kwon H, Lee YH, Kim MY, An KM, Kim K, Kim JS, Joo EY, Hong SB - J Clin Neurol (2015)

Bottom Line: ESI and MEG source imaging (MSI) results were well concordant with the results of presurgical evaluations (in 96.3% and 100% cases for ESI and MSI, respectively) at the lobar level.The ESI results were well concordant with MSI results in 90.0% of cases.The ESI analysis was found to be useful for localizing the seizure focus and is recommended for the presurgical evaluation of intractable epilepsy patients.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.

ABSTRACT

Background and purpose: The aim of this study was to determine the usefulness of three-dimensional (3D) scalp EEG source imaging (ESI) in partial epilepsy in comparison with the results of presurgical evaluation, magnetoencephalography (MEG), and electrocorticography (ECoG).

Methods: The epilepsy syndrome of 27 partial epilepsy patients was determined by presurgical evaluations. EEG recordings were made using 70 scalp electrodes, and the 3D coordinates of the electrodes were digitized. ESI images of individual and averaged spikes were analyzed by Curry software with a boundary element method. MEG and ECoG were performed in 23 and 9 patients, respectively.

Results: ESI and MEG source imaging (MSI) results were well concordant with the results of presurgical evaluations (in 96.3% and 100% cases for ESI and MSI, respectively) at the lobar level. However, there were no spikes in the MEG recordings of three patients. The ESI results were well concordant with MSI results in 90.0% of cases. Compared to ECoG, the ESI results tended to be localized deeper than the cortex, whereas the MSI results were generally localized on the cortical surface. ESI was well concordant with ECoG in 8 of 9 (88.9%) cases, and MSI was also well concordant with ECoG in 4 of 5 (80.0%) cases. The EEG single dipoles in one patient with mesial temporal lobe epilepsy were tightly clustered with the averaged dipole when a 3 Hz high-pass filter was used.

Conclusions: The ESI results were well concordant with the results of the presurgical evaluation, MSI, and ECoG. The ESI analysis was found to be useful for localizing the seizure focus and is recommended for the presurgical evaluation of intractable epilepsy patients.

No MeSH data available.


Related in: MedlinePlus

Different high-pass filter (HPF) setting. The 64 individual dipoles of patient #26 who had left mesial temporal lobe epilepsy. EEG dipoles were analyzed in preoperative boundary element method (BEM) head model in different HPF settings and superimposed on the postoperative MRI. HPF settings were as follow: (A) 0.5 Hz, (B) 1Hz, (C) 2 Hz, (D) 3 Hz, (E) 4 Hz, (F) 5 Hz, and (G) 6 Hz. Low pass filter settings were all 100 Hz. The H shows averaged dipoles of A-G with the matched color. Circles surrounding each dipole indicate confidence ellipsoid range. Each color indicates different HPF setting (red: 0.5 Hz, orange: 1 Hz, yellow: 2 Hz, green: 3 Hz, bright blue: 4 Hz, blue: 5 Hz, violet: 6 Hz). L: left, R: right.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4596098&req=5

Figure 3: Different high-pass filter (HPF) setting. The 64 individual dipoles of patient #26 who had left mesial temporal lobe epilepsy. EEG dipoles were analyzed in preoperative boundary element method (BEM) head model in different HPF settings and superimposed on the postoperative MRI. HPF settings were as follow: (A) 0.5 Hz, (B) 1Hz, (C) 2 Hz, (D) 3 Hz, (E) 4 Hz, (F) 5 Hz, and (G) 6 Hz. Low pass filter settings were all 100 Hz. The H shows averaged dipoles of A-G with the matched color. Circles surrounding each dipole indicate confidence ellipsoid range. Each color indicates different HPF setting (red: 0.5 Hz, orange: 1 Hz, yellow: 2 Hz, green: 3 Hz, bright blue: 4 Hz, blue: 5 Hz, violet: 6 Hz). L: left, R: right.

Mentions: The 64 individual EEG dipoles of patient #26, who had left MTLE, are plotted in Fig. 3. Dipoles were analyzed in a preoperative BEM head model for different HPF cutoffs, and are superimposed on postoperative MRI results in the figure. The HPF cutoffs were 0.5, 1, 2, 3, 4, 5, and 6 Hz for A to G in Fig. 3. The LPF cutoff was 100 Hz in all cases. Fig. 3H shows the dipoles of averaged 64 spikes for different HPF cutoffs using the same colors as in A-G. Individual EEG dipoles are dispersed in location and orientation around the averaged dipole.


EEG Source Imaging in Partial Epilepsy in Comparison with Presurgical Evaluation and Magnetoencephalography.

Park CJ, Seo JH, Kim D, Abibullaev B, Kwon H, Lee YH, Kim MY, An KM, Kim K, Kim JS, Joo EY, Hong SB - J Clin Neurol (2015)

Different high-pass filter (HPF) setting. The 64 individual dipoles of patient #26 who had left mesial temporal lobe epilepsy. EEG dipoles were analyzed in preoperative boundary element method (BEM) head model in different HPF settings and superimposed on the postoperative MRI. HPF settings were as follow: (A) 0.5 Hz, (B) 1Hz, (C) 2 Hz, (D) 3 Hz, (E) 4 Hz, (F) 5 Hz, and (G) 6 Hz. Low pass filter settings were all 100 Hz. The H shows averaged dipoles of A-G with the matched color. Circles surrounding each dipole indicate confidence ellipsoid range. Each color indicates different HPF setting (red: 0.5 Hz, orange: 1 Hz, yellow: 2 Hz, green: 3 Hz, bright blue: 4 Hz, blue: 5 Hz, violet: 6 Hz). L: left, R: right.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4596098&req=5

Figure 3: Different high-pass filter (HPF) setting. The 64 individual dipoles of patient #26 who had left mesial temporal lobe epilepsy. EEG dipoles were analyzed in preoperative boundary element method (BEM) head model in different HPF settings and superimposed on the postoperative MRI. HPF settings were as follow: (A) 0.5 Hz, (B) 1Hz, (C) 2 Hz, (D) 3 Hz, (E) 4 Hz, (F) 5 Hz, and (G) 6 Hz. Low pass filter settings were all 100 Hz. The H shows averaged dipoles of A-G with the matched color. Circles surrounding each dipole indicate confidence ellipsoid range. Each color indicates different HPF setting (red: 0.5 Hz, orange: 1 Hz, yellow: 2 Hz, green: 3 Hz, bright blue: 4 Hz, blue: 5 Hz, violet: 6 Hz). L: left, R: right.
Mentions: The 64 individual EEG dipoles of patient #26, who had left MTLE, are plotted in Fig. 3. Dipoles were analyzed in a preoperative BEM head model for different HPF cutoffs, and are superimposed on postoperative MRI results in the figure. The HPF cutoffs were 0.5, 1, 2, 3, 4, 5, and 6 Hz for A to G in Fig. 3. The LPF cutoff was 100 Hz in all cases. Fig. 3H shows the dipoles of averaged 64 spikes for different HPF cutoffs using the same colors as in A-G. Individual EEG dipoles are dispersed in location and orientation around the averaged dipole.

Bottom Line: ESI and MEG source imaging (MSI) results were well concordant with the results of presurgical evaluations (in 96.3% and 100% cases for ESI and MSI, respectively) at the lobar level.The ESI results were well concordant with MSI results in 90.0% of cases.The ESI analysis was found to be useful for localizing the seizure focus and is recommended for the presurgical evaluation of intractable epilepsy patients.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.

ABSTRACT

Background and purpose: The aim of this study was to determine the usefulness of three-dimensional (3D) scalp EEG source imaging (ESI) in partial epilepsy in comparison with the results of presurgical evaluation, magnetoencephalography (MEG), and electrocorticography (ECoG).

Methods: The epilepsy syndrome of 27 partial epilepsy patients was determined by presurgical evaluations. EEG recordings were made using 70 scalp electrodes, and the 3D coordinates of the electrodes were digitized. ESI images of individual and averaged spikes were analyzed by Curry software with a boundary element method. MEG and ECoG were performed in 23 and 9 patients, respectively.

Results: ESI and MEG source imaging (MSI) results were well concordant with the results of presurgical evaluations (in 96.3% and 100% cases for ESI and MSI, respectively) at the lobar level. However, there were no spikes in the MEG recordings of three patients. The ESI results were well concordant with MSI results in 90.0% of cases. Compared to ECoG, the ESI results tended to be localized deeper than the cortex, whereas the MSI results were generally localized on the cortical surface. ESI was well concordant with ECoG in 8 of 9 (88.9%) cases, and MSI was also well concordant with ECoG in 4 of 5 (80.0%) cases. The EEG single dipoles in one patient with mesial temporal lobe epilepsy were tightly clustered with the averaged dipole when a 3 Hz high-pass filter was used.

Conclusions: The ESI results were well concordant with the results of the presurgical evaluation, MSI, and ECoG. The ESI analysis was found to be useful for localizing the seizure focus and is recommended for the presurgical evaluation of intractable epilepsy patients.

No MeSH data available.


Related in: MedlinePlus