Neue Entwicklungen in der neuropathologischen Diagnostik fokaler Epilepsien

Zusammenfassung

Mit zunehmender Verfügbarkeit Epilepsie-chirurgischer Therapieverfahren stellen sich besondere Anforderungen an die neuropathologische Diagnostik. Die Durchsicht von 4 840 am Neuropathologischen Referenzzentrum für Epilepsie-Chirurgie gesammelten Fällen ergibt ein ungewöhnlich breites Spektrum histopathologischer Läsionen. Die häufige mesiale Temporallappensklerose ist durch segmentale Nervenzelluntergänge im Hippocampus gekennzeichnet. Eine neue histopathologische Klassifikation ist für die Prädiktion der postoperativen Anfallsfreiheit hilfreich. Bei Epilepsie-assoziierten Tumoren steht die Charakterisierung neuer Varianten und die Einstufung ihrer biologischen Wertigkeit im Mittelpunkt. Fehlbildungen der kortikalen Entwicklung finden sich in 14% der untersuchten Fälle. Bisherige Klassifikationsschemen berücksichtigen nur unzureichend die unterschiedlichen Läsionsmuster, vor allem in der Abgrenzung fokaler kortikalen Dysplasien. Weiterführende interdisziplinäre Studien sollen eine klinisch-genetische und pathologische Klassifikation zum besseren Verständnis der Ätiologie erarbeiten und die zielgerichtete Entwicklung neuer medikamentöser Therapiestrategien fördern.

Summary

The spectrum of brain lesions in patients with focal, therapy-refractory epilepsies is broad. In our experience with 4 840 surgical tissue samples collected at the German Neuropathological Reference Center for Epilepsy Surgery in Erlangen, major clinico-pathological entities comprise mesial temporal sclerosis, long-term epilepsy associated tumors, and malformations of cortical development. A histopathological and molecular-genetical analysis is mandatory to unravel the underlying pathogenic mechanisms of epilepsy-associated lesions and may contribute to our current understanding of pharmacoresistance and epileptogenesis. However, an interdisciplinary approach will be necessary to establish international classification systems for specific lesion entities and to further explore predictive parameters with respect to postsurgical seizure relief and memory impairment.

Schlüsselwörter

Anfälle - Hippocampus - Neurogenese - Gangliogliom - Dysplasie

Keywords

Seizure - hippocampus - neurogenesis - tumors - malformations

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