Die Rolle des MEG in der Epilepsiediagnostik

Zusammenfassung

Die zerebrale Magnetenzephalographie (MEG) ermöglicht eine nichtinvasive, kontakt- und referenzfreie Aufzeichnung von kortikaler Hirnaktivität. Mit der Entwicklung moderner Ganzkopfgeräte mit über 100 Aufzeichnungssensoren und der Verbesserung von mathematischen Modellen der Datenanalyse, hat sich das MEG zu einer ausgereiften Methodik entwickelt. Sie wird heute nicht nur in der neurowissenschaftlichen Hirnforschung angewandt, sondern findet als komplementäre Ergänzung zur Elektroenzephalographie auch zunehmend Eingang in die klinische Epilepsiediagnostik. In der prächirurgischen Diagnostik von Patienten mit einer pharmakoresistenten Epilepsie lässt sich mit dem MEG die irritative Zone in manchen Fällen nichtinvasiv lokalisieren. Erste Daten deuten darauf hin, dass sich mit dem MEG in der prächirurgischen Diagnostik auch eine Lokalisation kognitiver Funktionen, wie z. B. Sprache und Gedächtnis, erreichen lässt. Es sind noch weitere Studien erforderlich, um die Bedeutung dieser Methode in der Epilepsiediagnostik zu untermauern. Dennoch lassen die bisherigen Daten hoffen, dass in Zukunft das MEG im Zusammenspiel mit anderen bildgebenden Verfahren eine umfassende nichtinvasive Diagnostik ermöglichen könnte.

Abstract

Magnetoencephalography is a non-invasive tool that allows to obtain contact- and reference-free records of cortical activity. With the development of new whole-head imaging systems that have more than 100 recording sensors and with improved mathematical approaches to data analysis, MEG has evolved into a mature technique. Today, MEG is not only used for neuroscientific research, but also enters into the field of clinical epileptology. In presurgical evaluation of patients with pharmaco-resistant epilepsy, MEG can complement EEG to localize the irritative zone in a non-invasive manner. Initial data suggest that MEG also assists in the preoperative localisation of cognitive functions, such as language and memory. More studies are necessary to further establish MEG in the presurgical evaluation. Nevertheless, data available so far are promising and suggest that together with other imaging modalities MEG will allow a comprehensive non-invasive preoperative evaluation in the near future.

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