MRT- und CT-Diagnostik bei Epilepsiepatienten mit chronischem Verlauf

Zusammenfassung

Die diagnostische Abklärung von Patienten mit chronischen Epilepsien, die in ca. 30 % der Fälle als kryptogen eingestuft werden, stellt besondere Anforderungen an die bildgebende Diagnostik. Nur durch eine hochauflösende Bildgebung der Magnetresonanztomographie (MRT) kann hier die symptomatische Ursache von Epilepsien dargelegt und hierdurch einer adäquaten Therapie zugeführt werden. Der folgende Artikel gibt einen Überblick über ein für diese Patientengruppe optimiertes MRT-Untersuchungsprotokoll. Zusätzlich wird auf die Indikationen der Bildgebung in der Abklärung von Epilepsien eingegangen. Zahlreiche Abbildungen veranschaulichen die häufigsten Befunde bei chronischen Epilepsien. Hierbei werden neben Heterotopien, Hippokampussklerosen und tumorösen Raumforderungen auch auf seltene Krankheitsbilder wie kortikale Dysgenisien, Lissenzephalien, Schizenzephalien und Polymikrogyrien eingegangen. Abschließend werden die Möglichkeiten der funktionellen MR-Bildgebung in der Epilepsiediagnostik dargestellt.

Abstract

Diagnosis in patients with chronic epilepsy, of which 30 % still remain cryptogenic, is still a challenge. In this patient group imaging modalities play an important role for sufficient diagnosis. In most cases only high resolution imaging of the CNS is able to determine the symptomatic lesions, which is the basis for rational therapy strategies. The following article presents an overview of optimised standard examination protocols in Magnetic Resonance Imaging (MRI) and their indications in the diagnosis of epilepsies. Numerous images illustrate current findings in the mentioned patient group. In addition to heterotopias, hippocampal sclerosis and intracranial neoplasm, infrequent diseases like cortical dysgenesis, lissencephalies, schizencephalies and polymicrogyria are presented. Applications of functional MRI in the diagnosis of epilepsies are illustrated in the end.

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