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Predictability of uncontrollable multifocal seizures - towards new treatment options.

Lehnertz K, Dickten H, Porz S, Helmstaedter C, Elger CE - Sci Rep (2016)

Bottom Line: Drug-resistant, multifocal, non-resectable epilepsies are among the most difficult epileptic disorders to manage.Our findings clearly indicate that epileptic networks, spanning lobes and hemispheres, underlie generation of seizures.Our proof-of-concept study is an important milestone towards new therapeutic strategies based on seizure-prediction techniques for clinical practice.

View Article: PubMed Central - PubMed

Affiliation: Department of Epileptology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany.

ABSTRACT
Drug-resistant, multifocal, non-resectable epilepsies are among the most difficult epileptic disorders to manage. An approach to control previously uncontrollable seizures in epilepsy patients would consist of identifying seizure precursors in critical brain areas combined with delivering a counteracting influence to prevent seizure generation. Predictability of seizures with acceptable levels of sensitivity and specificity, even in an ambulatory setting, has been repeatedly shown, however, in patients with a single seizure focus only. We did a study to assess feasibility of state-of-the-art, electroencephalogram-based seizure-prediction techniques in patients with uncontrollable multifocal seizures. We obtained significant predictive information about upcoming seizures in more than two thirds of patients. Unexpectedly, the emergence of seizure precursors was confined to non-affected brain areas. Our findings clearly indicate that epileptic networks, spanning lobes and hemispheres, underlie generation of seizures. Our proof-of-concept study is an important milestone towards new therapeutic strategies based on seizure-prediction techniques for clinical practice.

No MeSH data available.


Related in: MedlinePlus

Comparison of the distributions of pre-seizure changes in synchrony in critical brain areas between patient groups.Boxplots of the average relative change in synchrony  between critical brain areas ( and  denote the medians of R-values from the respective pre-ictal and inter-ictal periods) for patients with chronic intractable epilepsy (group 1, filled box) and for patients in the control group (group 2, hatched boxes). Module interactions: f–f (within the seizure onset zone), f–o (between seizure onset zone and remote brain areas), and o–o (between remote brain areas). Only data from the final stage of statistical analyses are shown. Bottom and top of a box are the first and third quartiles, and the (red) band inside a box is the median. The ends of the whiskers represent the minimum and maximum of the data.
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f5: Comparison of the distributions of pre-seizure changes in synchrony in critical brain areas between patient groups.Boxplots of the average relative change in synchrony between critical brain areas ( and denote the medians of R-values from the respective pre-ictal and inter-ictal periods) for patients with chronic intractable epilepsy (group 1, filled box) and for patients in the control group (group 2, hatched boxes). Module interactions: f–f (within the seizure onset zone), f–o (between seizure onset zone and remote brain areas), and o–o (between remote brain areas). Only data from the final stage of statistical analyses are shown. Bottom and top of a box are the first and third quartiles, and the (red) band inside a box is the median. The ends of the whiskers represent the minimum and maximum of the data.

Mentions: We checked whether the aforementioned module combinations were preferentially critical across a patient group. For the critical module combinations in group 1, we found that only the number of patients with interactions between brain regions not related to initial ictal discharges (o–o interactions) exceeded what was expected by chance (hypergeometric test; p < 0.05). In these non-affected brain regions, a loss of synchrony (−6.6% on average) can be regarded as a potential seizure precursor (see Fig. 5). For the critical module combinations in the control group (group 2), the number of patients with alterations in synchrony of within-module interactions of the SOZ (f–f) and of remote brain areas (o–o) as well as their between-module interactions (f–o) exceeded what was expected by chance (hypergeometric test; p < 0.05). Potential seizure precursor were characterized by a slightly decreased pre-ictal synchrony (−6.2% on average) within the SOZ but also by a slightly increased pre-ictal synchrony between SOZ and other brain regions (+2.2% on average) and a more pronounced increase of synchrony (+10.7% on average) between remote brain regions (see Fig. 5).


Predictability of uncontrollable multifocal seizures - towards new treatment options.

Lehnertz K, Dickten H, Porz S, Helmstaedter C, Elger CE - Sci Rep (2016)

Comparison of the distributions of pre-seizure changes in synchrony in critical brain areas between patient groups.Boxplots of the average relative change in synchrony  between critical brain areas ( and  denote the medians of R-values from the respective pre-ictal and inter-ictal periods) for patients with chronic intractable epilepsy (group 1, filled box) and for patients in the control group (group 2, hatched boxes). Module interactions: f–f (within the seizure onset zone), f–o (between seizure onset zone and remote brain areas), and o–o (between remote brain areas). Only data from the final stage of statistical analyses are shown. Bottom and top of a box are the first and third quartiles, and the (red) band inside a box is the median. The ends of the whiskers represent the minimum and maximum of the data.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4835791&req=5

f5: Comparison of the distributions of pre-seizure changes in synchrony in critical brain areas between patient groups.Boxplots of the average relative change in synchrony between critical brain areas ( and denote the medians of R-values from the respective pre-ictal and inter-ictal periods) for patients with chronic intractable epilepsy (group 1, filled box) and for patients in the control group (group 2, hatched boxes). Module interactions: f–f (within the seizure onset zone), f–o (between seizure onset zone and remote brain areas), and o–o (between remote brain areas). Only data from the final stage of statistical analyses are shown. Bottom and top of a box are the first and third quartiles, and the (red) band inside a box is the median. The ends of the whiskers represent the minimum and maximum of the data.
Mentions: We checked whether the aforementioned module combinations were preferentially critical across a patient group. For the critical module combinations in group 1, we found that only the number of patients with interactions between brain regions not related to initial ictal discharges (o–o interactions) exceeded what was expected by chance (hypergeometric test; p < 0.05). In these non-affected brain regions, a loss of synchrony (−6.6% on average) can be regarded as a potential seizure precursor (see Fig. 5). For the critical module combinations in the control group (group 2), the number of patients with alterations in synchrony of within-module interactions of the SOZ (f–f) and of remote brain areas (o–o) as well as their between-module interactions (f–o) exceeded what was expected by chance (hypergeometric test; p < 0.05). Potential seizure precursor were characterized by a slightly decreased pre-ictal synchrony (−6.2% on average) within the SOZ but also by a slightly increased pre-ictal synchrony between SOZ and other brain regions (+2.2% on average) and a more pronounced increase of synchrony (+10.7% on average) between remote brain regions (see Fig. 5).

Bottom Line: Drug-resistant, multifocal, non-resectable epilepsies are among the most difficult epileptic disorders to manage.Our findings clearly indicate that epileptic networks, spanning lobes and hemispheres, underlie generation of seizures.Our proof-of-concept study is an important milestone towards new therapeutic strategies based on seizure-prediction techniques for clinical practice.

View Article: PubMed Central - PubMed

Affiliation: Department of Epileptology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany.

ABSTRACT
Drug-resistant, multifocal, non-resectable epilepsies are among the most difficult epileptic disorders to manage. An approach to control previously uncontrollable seizures in epilepsy patients would consist of identifying seizure precursors in critical brain areas combined with delivering a counteracting influence to prevent seizure generation. Predictability of seizures with acceptable levels of sensitivity and specificity, even in an ambulatory setting, has been repeatedly shown, however, in patients with a single seizure focus only. We did a study to assess feasibility of state-of-the-art, electroencephalogram-based seizure-prediction techniques in patients with uncontrollable multifocal seizures. We obtained significant predictive information about upcoming seizures in more than two thirds of patients. Unexpectedly, the emergence of seizure precursors was confined to non-affected brain areas. Our findings clearly indicate that epileptic networks, spanning lobes and hemispheres, underlie generation of seizures. Our proof-of-concept study is an important milestone towards new therapeutic strategies based on seizure-prediction techniques for clinical practice.

No MeSH data available.


Related in: MedlinePlus